CN115677879A

CN115677879A - Catalyst for preparing cycloolefin copolymer, preparation method of cycloolefin copolymer, cycloolefin copolymer and application of cycloolefin copolymer

Info

Publication number: CN115677879A
Application number: CN202110879346.3A
Authority: CN
Inventors: 简忠保; 张燚鑫; 崔磊; 邹海良; 陈辰; 季鹤源
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-07-31
Filing date: 2021-07-31
Publication date: 2023-02-03
Also published as: WO2023011383A1

Abstract

The embodiment of the application provides a catalyst for preparing a cycloolefin copolymer, which comprises a main catalyst shown as a formula (1-a):

d is a bridging group and Q is a metal center; r ₅ 、R ₆ 、R ₇ 、R ₈ Independently comprises a hydrogen atom, a hydrocarbyl group or a silicon-containing substituent which is bonded to the carbon atom at the corresponding substitution position through a silicon atom; r _a 、R _b Is a carbon-containing group, a silicon-containing group, a germanium-containing group or a tin-containing group; r ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is a silicon-containing substituent, and/or said R _a 、R _b At least one of which is a silicon-containing group; r is ₉ 、R ₁₃ 、R ₁₄ 、R ₁₈ Independently a hydrogen atom, a hydrocarbyl group or a hydrocarbyloxy group. The catalyst can be used for preparing the low molecular weight cycloolefin copolymer without additionally introducing molecular weight regulators such as hydrogen or propylene, and simultaneously, the cycloolefin copolymer has moderate glass transition temperature.

Description

Catalyst for preparing cycloolefin copolymer, preparation method of cycloolefin copolymer, cycloolefin copolymer and application of cycloolefin copolymer

Technical Field

The embodiment of the application relates to the technical field of engineering plastic preparation, in particular to a catalyst for preparing a cyclic olefin copolymer, a preparation method of the cyclic olefin copolymer, the cyclic olefin copolymer and application thereof.

Background

Cycloolefin polymers are thermoplastic engineering plastics with high added value, and have been widely used in the fields of various electronic products, automobile headlights, glasses, medical and food packaging materials and the like due to their excellent properties such as optical transparency, heat resistance, chemical stability, melt fluidity, moisture insulation, dimensional stability, low dielectric constant and the like.

There are two main routes for the synthesis of cyclic olefin polymers: one method is a chain addition copolymerization of ethylene or α -Olefin (which means a monoolefin having a double bond at the end of the molecular chain) with a norbornene-type cycloolefin monomer (as shown in chemical formula (1), m and n represent the degree of polymerization), and the polymer prepared by this method is also called a Cyclic Olefin Copolymer (COC); another method is ring-opening metathesis polymerization (ROMP) of a cycloolefin monomer such as norbornene and the like and subsequent hydrogenation (n represents a polymerization degree as shown in chemical reaction formula (2)), and the Polymer thus obtained is also referred to as a cycloolefin homopolymer (COP).

Molecular weight and Glass transition temperature (T) of cyclic olefin polymers during synthesis, processing and practical application _g ) Are two key performance indicators. The molecular weight significantly affects the mechanical properties and processability of the cycloolefin polymer. When the molecular weight of the cycloolefin polymer is high (for example, the weight average molecular weight is more than 10 ten thousand), the Melt Flow index (MFR) is low and the processing is difficult. When the cycloolefin polymer T is _g When the content is too high, the cycloolefin polymer is difficult to process or injection-molded; t is _g When too low, the use environment and conditions of the cycloolefin polymer are limited. Thus, for the practical application of COC, there is a need to find an efficient process for the preparation of a composition having both a low molecular weight (weight average molecular weight less than or equal to 15 ten thousand) and a moderate T _g (110 ℃ to 180 ℃) of a cycloolefin copolymer.

Disclosure of Invention

In view of this, embodiments of the present application provide a catalyst for preparing a cycloolefin copolymer, by which a cycloolefin copolymer having a low molecular weight (a weight average molecular weight of 15 ten thousand or less) can be prepared without additionally introducing a molecular weight modifier such as hydrogen or propylene, while ensuring that the cycloolefin copolymer has a moderate glass transition temperature (110 ℃ to 180 ℃).

In a first aspect, embodiments of the present application provide a catalyst for preparing a cycloolefin copolymer, the catalyst including a main catalyst having a structural formula shown in formula (1-a):

in the formula (1-a), D is a bridging group, and Q is a metal center;

R ₅ 、R ₆ 、R ₇ 、R ₈ independently comprises a hydrogen atom, a hydrocarbyl group or a silicon-containing substituent which is bonded to the carbon atom at the corresponding substitution position through a silicon atom;

R _a 、R _b is a carbon-containing group, a silicon-containing group, a germanium-containing group or a tin-containing group;

said R is ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is a silicon-containing substituent, and/or said R _a 、R _b At least one of which is a silicon-containing group;

R ₉ 、R ₁₃ 、R ₁₄ 、R ₁₈ independently a hydrogen atom, a hydrocarbyl group or a hydrocarbyloxy group.

The catalyst for preparing the cyclic olefin copolymer provided by the embodiment of the application comprises a main catalyst shown as a formula (1-a), wherein the main catalyst is a cyclopentadienyl-fluorene bridged transition metal catalyst, a silicon-containing heteroatom group is introduced on cyclopentadienyl or fluorenyl of the main catalyst, and in the copolymerization process of ethylene, alpha-olefin and cyclic olefin monomers, the metal center of the main catalyst and the silicon atom introduced on the cyclopentadienyl or fluorenyl generate a synergistic effect, so that the chain transfer in the polymerization process can be promoted, the insertion rate of the cyclic olefin monomers is improved, and the cyclic olefin copolymer with low molecular weight (the weight average molecular weight is less than or equal to 15 ten thousand) and moderate glass transition temperature can be obtained through a chain addition copolymerization mode without additionally introducing molecular weight regulators such as hydrogen or propylene. The obtained cycloolefin copolymer has lower melt flow index due to lower molecular weight, good processing performance, moderate glass transition temperature, and better heat resistance, and can avoid the problem that the cycloolefin copolymer is difficult to process and injection-molded due to too high glass transition temperature, so that the cycloolefin copolymer is suitable for various application scenes.

In the embodiments of the present application, the metal center Q is represented by-M ¹ (R ₁ R ₂ ) -, said M ¹ Represents scandium, titanium, vanadium, zirconium, hafnium, niobium or tantalum, said R ₁ And R ₂ Independently include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, an aryl group, an aryloxy group, an aralkyl group, an alkaryl group or an aralkenyl group.

In an embodiment of the application, the bridging group D is represented by-X (R) ₃ R ₄ ) -, said X represents carbon or silicon, said R ₃ And R ₄ Independently comprise a hydrogen atom or a hydrocarbyl group.

In the embodiments of the present application, R is _a Is represented by-M ² (R ₁₀ R ₁₁ R ₁₂ ) Said R is _b Is represented by-M ³ (R ₁₅ R ₁₆ R ₁₇ )，M ² 、M ³ Independently represent carbon, silicon, germanium or tin, R ₁₀ 、R ₁₁ 、R ₁₂ 、R ₁₅ 、R ₁₆ 、R ₁₇ Independently include alkyl, alkoxy, alkenyl, aryl, aryloxy, aralkyl, alkaryl, or aralkenyl.

In one embodiment of the present application, the main catalyst represented by formula (1-a) has a specific structural formula represented by formula (1-b):

in some embodiments of the present application, R ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is a silicon-containing substituent, R _a 、R _b Not being a silicon-containing group, R _a 、R _b Is a carbon-containing group, a germanium-containing group or a tin-containing group, i.e. M ² 、M ³ Independently comprise carbon, germanium or tin. In other embodiments of the present application, R _a 、R _b At least one being a silicon-containing group, i.e. M ² 、M ³ One or both of which are silicon, R ₅ 、R ₆ 、R ₇ 、R ₈ Not being a silicon-containing substituent, R ₅ 、R ₆ 、R ₇ 、R ₈ Is a hydrogen atom or a hydrocarbon group. In other embodiments of the present application, R _a 、R _b At least one being a silicon-containing group, i.e. M ² 、M ³ One or both of which are silicon, while R is ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is a silicon-containing substituent.

In some embodiments of the present application, R is ₆ 、R ₇ At least one of which is a silicon-containing substituent, and/or said R _a 、R _b At least one of which is a silicon-containing group. The silicon-containing substituents being located at the 3-and 4-positions of the cyclopentadiene compared to the 2-and 5-positions from the metal centre M ¹ Furthermore, silicon-containing substituent groups are introduced into the 3-position and the 4-position of the cyclopentadiene, so that the silicon-containing substituent groups can be reacted with a metal center M ¹ Weak coordination is formed to promote chain transfer, the molecular weight of the polymer is reduced, and the influence on the polymerization reaction activity of the catalyst due to strong coordination action can be avoided.

In an embodiment of the present application, R ₅ 、R ₆ 、R ₇ 、R ₈ The number of carbon atoms of the medium hydrocarbon group and the silicon-containing substituent is less than or equal to 6.

In an embodiment of the present application, R ₁₀ 、R ₁₁ 、R ₁₂ 、R ₁₅ 、R ₁₆ 、R ₁₇ Has a carbon number of 10 or less.

In the embodiment of the present application, the catalyst for preparing cyclic olefin copolymer further comprises a cocatalyst, which includes, but is not limited to, one or more of methylaluminoxane, modified methylaluminoxane, and organoboron compound. In embodiments herein, the organoboron compound includes one or more of tris (pentafluorophenyl) boron, triphenylcarbenium tetrakis (pentafluorophenyl) borate, and N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate. Methyl aluminoxane, modified methyl aluminoxane and organic boron compound are used as cocatalyst, which is beneficial to ensuring the copolymerization reaction activity of the preparation of the cycloolefin copolymer.

In an embodiment of the present application, the molar ratio of the main catalyst represented by the formula (1-a) to the cocatalyst is 1: (10-10000).

In the embodiment of the application, the catalytic reaction activity of the catalyst is higher than 10 ⁶ g·mol ^-1 ·h ^-1 . The main catalyst shown in the formula (1-a) has high catalytic reaction activity when being used for preparing cycloolefin copolymer.

In the embodiment of the present application, the main catalyst and the cocatalyst may be supported on a carrier. The support may be, for example, silica, alumina, titania, or the like.

In a second aspect, embodiments of the present application provide a method for preparing a cycloolefin copolymer, including:

in the presence of the catalyst for preparing a cycloolefin copolymer according to the first aspect, a cycloolefin monomer is copolymerized with ethylene or an α -olefin to obtain a cycloolefin copolymer.

In the embodiment of the application, the reaction system of the copolymerization comprises an inert solvent, and the inert solvent comprises one or more of straight-chain alkane compounds, cyclic hydrocarbon compounds and aromatic hydrocarbon compounds.

In the embodiment of the application, the dosage of the main catalyst shown in formula (1-a) in the reaction system of the copolymerization is 0.001mmol/L-10mmol/L.

In the embodiment of the present application, the cycloolefin monomer is used in an amount of 0.01mol/L to 10mol/L in the reaction system of the copolymerization.

In the embodiment of the present application, the molar ratio of the cycloolefin monomer to the procatalyst in the copolymerization reaction system is 500 to 500000. The main catalyst can adapt to the usage amount of cycloolefin monomers in a larger range, and has high catalytic activity.

In the embodiment of the application, the temperature of the copolymerization reaction is 50-120 ℃; the time of the copolymerization reaction is 2min-10min. The preparation method of the cycloolefin copolymer has the advantages of low requirement on the copolymerization reaction temperature, short time and high efficiency.

In an embodiment of the present application, the structural formula of the cycloolefin monomer is represented by formula (2):

in the formula (2), R ₁₉ Is hydrocarbyl or hydrocarbyl silyl; r ₂₀ And R ₂₁ Each independently comprises a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, an atom or an atomic group which may substitute for the above group;

R ₂₂ and R ₂₃ Each independently of the other, a hydrogen atom, a halogen atom, an alkyl group,Alkoxy, aryl, aryloxy, hydroxyl, ester, carbonate, cyano, amino, thiol, an atom or group of atoms which may be substituted for the above groups, or R ₂₂ And R ₂₃ Linked to form a group having a cyclic structure;

z is a positive integer.

In an embodiment herein, the α -olefin may be propylene, 1-butene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, or 2-ethyl-1-butene.

In the embodiment of the present application, the copolymerization reaction system does not contain a molecular weight regulator. Examples of the molecular weight regulator include hydrogen, propylene and the like. The addition of molecular weight regulators not only makes the preparation process more complicated, but also affects the polymerization itself. For example, the introduction of hydrogen can reduce the activity of the catalyst system, while the introduction of propylene can introduce propylene molecules into the polymer, affecting the structure of the cyclic olefin copolymer.

According to the preparation method of the cycloolefin copolymer provided by the embodiment of the application, by adopting the catalyst provided by the first aspect of the embodiment of the application, the cycloolefin copolymer with low molecular weight and moderate glass transition temperature can be prepared without additionally introducing molecular weight regulators such as hydrogen or propylene, so that the requirements of processing performance, heat resistance and the like of various optical products such as optical lenses and the like, display materials, packaging materials and the like are met. The preparation method not only greatly simplifies the preparation approach of the cycloolefin copolymer material, but also obviously improves the polymerization activity and the energy and economic benefits, and opens up a new path for producing the cycloolefin copolymer material on a large scale.

In a third aspect, embodiments of the present application provide a cyclic olefin copolymer prepared according to the preparation method of the second aspect, wherein the structural formula of the cyclic olefin copolymer is represented by formula (3):

in the formula (3), R ₁₉ Is a hydrocarbon radicalOr hydrocarbyl silicon groups; r ₂₀ And R ₂₁ Each independently includes a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, an atom or an atomic group which may substitute the above groups;

R ₂₂ 、R ₂₃ 、R ₂₄ 、R ₂₅ each independently comprises a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, an atom or atom group which may be substituted for the above groups, or R ₂₂ And R ₂₃ Are linked to form a group having a cyclic structure, R ₂₄ And R ₂₅ Linked to form a group having a cyclic structure;

x and y represent polymerization degree, both x and y are positive numbers, 1 < x: y < 3, and z is a positive integer.

In an embodiment of the present application, the cycloolefin copolymer has a weight average molecular weight in a range of 5000 to 150000 (g/mol); the molecular weight distribution index is in the range of 1.5 to 3.0.

In an embodiment of the present application, the insertion rate of the cycloolefin monomer of the cycloolefin copolymer is in a range of 20% to 60%; the glass transition temperature of the cycloolefin copolymer is in the range from 110 ℃ to 180 ℃.

In the embodiment of the present application, the molded article of the cycloolefin copolymer has a visible light transmittance of more than 90%.

In a fourth aspect, the present application provides a composition comprising a cyclic olefin copolymer as described in the third aspect of the present application, or comprising a cyclic olefin copolymer prepared by the preparation method described in the second aspect.

In embodiments of the present application, the composition further comprises an additive comprising one or more of a filler, a dye, an antioxidant, a light stabilizer, an ultraviolet absorber, a plasticizer, a flame retardant, an antistatic agent, a mold release agent.

In a fifth aspect, embodiments provide an optical article comprising the cyclic olefin copolymer described in the third aspect of the embodiments, or comprising the cyclic olefin copolymer prepared by the preparation method described in the second aspect.

In embodiments of the present application, the optical article comprises an optical lens, an optical film, an optical disc, a light guide plate, or a display panel. The optical lens comprises a glasses lens, a camera lens, a sensor lens, an illuminating lens and an imaging lens.

Embodiments of the present application also provide an apparatus comprising an optical article as described in the fifth aspect of embodiments of the present application.

The embodiment of the application also provides an electronic device, which comprises an electronic device body and a camera module assembled on the electronic device body, wherein the camera module comprises a lens, and the lens is prepared from the cycloolefin copolymer according to the third aspect or the composition according to the fourth aspect.

Drawings

Fig. 1 is a schematic structural diagram of an apparatus 100 provided in an embodiment of the present application;

FIG. 2 shows the structure of example 1 of the present application nuclear magnetic resonance hydrogen spectrum of catalyst A: ( ¹ H Nuclear Magnetic Resonance Spectroscopy， ¹ H NMR)；

FIG. 3 shows the results of example 1 of the present application nuclear magnetic resonance carbon spectrum of catalyst A: ( ¹³ C Nuclear Magnetic Resonance Spectroscopy， ¹³ C NMR)；

FIG. 4 is a NMR spectrum of a cycloolefin monomer in example 1 of the present application;

FIG. 5 shows a nuclear magnetic resonance carbon spectrum of a cycloolefin monomer according to example 1 of the present application;

FIG. 6 is a NMR spectrum of a cycloolefin copolymer in example 1 of the present application;

FIG. 7 is a nuclear magnetic resonance carbon spectrum of a cycloolefin copolymer according to example 1 of the present application;

FIG. 8 is a DSC (Differential Scanning Calorimetry) curve of the cycloolefin copolymer according to example 1 of the present application;

FIG. 9 is a visible light transmittance test curve of a cycloolefin copolymer according to example 1 of the present application;

FIG. 10 is a DSC curve of the cycloolefin copolymer according to example 2 of the present application;

FIG. 11 is a DSC curve of the cycloolefin copolymer according to example 3 of the present application;

FIG. 12 is a DSC curve of the cycloolefin copolymer according to example 4 of the present application;

FIG. 13 is a DSC curve of the cycloolefin copolymer according to example 5 of the present application.

Detailed Description

The following description will be made with reference to the drawings in the embodiments of the present application.

The molecular weight and the glass transition temperature of the cycloolefin copolymer COC are two key performance indexes, the molecular weight influences the processability, and the glass transition temperature influences the processability, the use environment and conditions. At present, metallocene catalysts are generally used for preparing cycloolefin copolymers, but the molecular weight of the cycloolefin copolymers directly prepared by using the existing metallocene catalysts is generally 20 ten thousand or more, the melt flow index is low, the processing is difficult, and the commercial value is low. In order to obtain a cycloolefin copolymer having a low molecular weight, a conventional method additionally introduces a molecular weight regulator such as hydrogen and propylene during the preparation process, and the additional introduction of the molecular weight regulator may reduce the catalytic activity of the catalyst, may also introduce the molecular weight regulator into the cycloolefin copolymer, and affects the structure of the cycloolefin copolymer, and the additional introduction of the molecular weight regulator may also complicate the preparation process. In addition, in the copolymerization process using ethylene or α -olefin and cycloolefin monomer, the glass transition temperature of COC of the cycloolefin copolymer can be adjusted by adjusting the insertion rate of the cycloolefin monomer in the copolymer.

In order to obtain a cyclic olefin copolymer COC having a relatively low molecular weight and a suitable glass transition temperature, embodiments of the present application provide a catalyst for preparing a cyclic olefin copolymer, which can be used to directly prepare a cyclic olefin copolymer having a low molecular weight and a suitable glass transition temperature without additionally introducing a molecular weight modifier such as hydrogen or propylene, and the catalyst includes a procatalyst having a structural formula shown in formula (1-a):

in the formula (1-a), D is a bridging group, and Q is a metal center;

In the catalyst for preparing cycloolefin copolymer provided in the embodiment of the present application, the main catalyst shown in formula (1-a) is a cyclopentadienylfluorene-bridged transition metal catalyst, a silicon-containing heteroatom group is introduced to 2-position or 7-position of cyclopentadienyl or fluorenyl in the cyclopentadienylfluorene-bridged transition metal catalyst, and in the process of copolymerizing ethylene or alpha-olefin and cycloolefin monomer, a metal center M of the main catalyst is ¹ The modified cyclic olefin copolymer has synergistic effect with silicon atom introduced into cyclopentadienyl or fluorenyl, and can promote chain transfer in the polymerization process and raise the insertion rate of cyclic olefin monomer, so that cyclic olefin copolymer with low molecular weight and moderate glass transition temperature may be obtained without introducing hydrogen, propylene and other molecular weight regulator. In particular, the silicon atom and the metal center M are introduced on the cyclopentadienyl or fluorenyl ¹ The empty orbitals producing a weak coordination with the olefin-metal center M ¹ The coordination between the two generates competition, thereby promoting chain transfer, reducing the molecular weight of the polymer and enabling the cyclic olefin copolymer to have low molecular weight; at the same time, the competition effect increases the ethylene or alpha-olefin and the metal center M ¹ The difficulty of coordination improves the insertion rate of cycloolefin monomers, thereby playing a role in adjusting the glass transition temperatureTherefore, the cycloolefin copolymer has moderate glass transition temperature and is suitable for various application scenes. The catalyst for preparing the cycloolefin copolymer in the embodiment of the application can enable the preparation of the cycloolefin copolymer with low molecular weight to be simpler, more convenient and more efficient, greatly simplifies the polymerization process and polymerization equipment, and is beneficial to large-scale production of the cycloolefin copolymer with low molecular weight. Meanwhile, other properties of the cycloolefin polymer, such as optical property, thermal property, mechanical property and the like, can reach the level of the COC material with low molecular weight prepared by the traditional method, so that the application scene of the COC material prepared by the traditional method can be adapted.

In an embodiment of the application, the bridging group D is represented by-X (R) ₃ R ₄ ) -, X represents carbon or silicon, R ₃ And R ₄ Independently comprise a hydrogen atom or a hydrocarbyl group.

In the embodiments of the present application, R is _a Is represented by-M ² (R ₁₀ R ₁₁ R ₁₂ ) Said R is _b Is represented by-M ³ (R ₁₅ R ₁₆ R ₁₇ )，M ² 、M ³ Independently represent carbon, silicon, germanium or tin, R ₁₀ 、R ₁₁ 、R ₁₂ 、R ₁₅ 、R ₁₆ 、R ₁₇ Independently include alkyl, alkoxy, alkenyl, aryl, aryloxy, aralkyl, alkaryl, or aralkenyl. R is _a By M ² To the carbon atom in the corresponding position on the fluorene ring, R _b By M ³ Is connected with the carbon atom at the corresponding position on the fluorene ring.

in the embodiment of the present application, the procatalyst represented by the formula (1-b) is a bridged bis-metallocene transition metal compound, M ¹ As the metal center, an early transition metal such as scandium, titanium, vanadium, zirconium, hafnium, niobium or tantalum, R ₁ And R ₂ With a metal centre M ¹ Is connected to R ₁ And R ₂ Independently include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, an aryl group, an aryloxy group, an aralkyl group, an alkaryl group or an aralkenyl group. Cyclopentadiene and fluorene via a bridging group-X (R) ₃ R ₄ ) -linked, cyclopentadiene and fluorene and metal centre M ¹ And (4) coordination bonding. X represents carbon or silicon, R ₃ And R ₄ Independently comprises a hydrogen atom or a hydrocarbyl group which may be an alkyl, alkenyl, aryl, aralkyl, alkaryl or aralkenyl group. Specifically, the hydrocarbon group may be an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkaryl group or an aralkenyl group having 10 or less carbon atoms (i.e., 1 to 10 carbon atoms). In some embodiments of the present application, R ₃ And R ₄ Or may be connected into a ring structure.

In the embodiment of the present application, in the formula (1-b), R ₁ And R ₂ When it is a halogen atom, the halogen atom may be fluorine, chlorine, bromine or iodine. In the present embodiment, the alkyl group may be a linear, branched or cyclic alkyl group. The alkyl group may be an unsubstituted alkyl group or a substituted alkyl group. The alkenyl group may be a straight-chain or branched alkenyl group. The alkenyl group may be an unsubstituted alkenyl group or a substituted alkenyl group. The alkoxy group may be a linear, branched or cyclic alkoxy group. In the embodiments of the present application, the number of carbon atoms in the alkyl group, the alkoxy group, or the alkenyl group may be 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. Specifically, the alkyl group may be, for example, a methyl group, an ethyl group, a propyl group, a butyl group, or the like. In the embodiments, the aryl group may be an unsubstituted aryl group or a substituted aryl group. The number of carbon atoms of the aryl, aryloxy, aralkyl, alkaryl, aralkenyl group may be 6, 7, 8, 9, 10. In some embodiments of the present application, the bridging group-X (R) ₃ R ₄ ) Examples of such may be, but are not limited to, methylene,Ethylene, isopropylidene (-C (CH) ₃ ) ₂ -), benzhydryl (-C (C) ₆ H ₅ ) ₂ -) bis (trimethylsilylmethylene (-C) (Si (CH) ₃ ) ₃ ) ₂ -) and the like.

In the embodiment of the present application, in the formula (1-b), R ₅ 、R ₆ 、R ₇ 、R ₈ May independently comprise a hydrogen atom, a hydrocarbyl group or a silicon-containing substituent. Specifically, the hydrocarbon group may be an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkaryl group or an aralkenyl group having 10 or less carbon atoms (i.e., 1 to 10 carbon atoms). The alkyl group may be a linear, branched or cyclic alkyl group. The alkyl group may be an unsubstituted alkyl group or a substituted alkyl group. The alkenyl group may be a straight-chain or branched alkenyl group. The alkenyl group may be an unsubstituted alkenyl group or a substituted alkenyl group. The number of carbon atoms of the alkyl group or alkenyl group may be 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. Specifically, the alkyl group may be, for example, a methyl group, an ethyl group, a propyl group, a butyl group, or the like. In the embodiments, the aryl group may be an unsubstituted aryl group or a substituted aryl group. The number of carbon atoms of the aryl, aralkyl, alkaryl, aralkenyl group may be 6, 7, 8, 9, 10.R ₅ 、R ₆ 、R ₇ 、R ₈ Respectively corresponding to the 2-position, 3-position, 4-position and 5-position carbon atoms of cyclopentadiene. In the embodiments of the present application, R ₅ 、R ₆ 、R ₇ Or R ₈ In the case of a silicon-containing substituent, the silicon-containing substituent forms a carbon-silicon bond with a carbon atom at the 2-, 3-, 4-or 5-position of the cyclopentadiene. In the embodiments of the present application, R may be ₅ 、R ₆ 、R ₇ And R ₈ One of these is a silicon-containing substituent, which may also be R ₅ 、R ₆ 、R ₇ And R ₈ Two or three or four of them are silicon-containing substituents. When R is ₅ 、R ₆ 、R ₇ And R ₈ When the central moiety is a silicon-containing substituent, the group other than the silicon-containing substituent may be a hydrogen atom or a hydrocarbon group. When R is ₅ 、R ₆ 、R ₇ And R ₈ When a plurality of these are silicon-containing substituents, the same silicon-containing substituents may be used, or different silicon-containing substituents may be used. When R is ₅ 、R ₆ 、R ₇ And R ₈ When a plurality of them are hydrocarbon groups, they may be the same hydrocarbon group or different hydrocarbon groups. The silicon-containing substituent is bonded to the carbon atom at the corresponding substitution position through a silicon atom, i.e., the silicon-containing substituent is bonded to the carbon atom on the cyclopentadienyl ring at the corresponding position through a silicon atom, and the silicon-containing substituent may be represented by-Si (R 'R "R'"), R ', R ", R'" may be an alkyl group or an aryl group, i.e., the silicon-containing substituent may be an alkylsilyl group or an arylsilyl group. The alkylsilyl group may specifically be, for example, a trimethylsilanyl group (i.e., R ', R ", R'" is a methyl group), a triethylsilyl group (i.e., R ', R ", R'" is an ethyl group), etc., and the arylsilyl group may specifically be, for example, a triphenylsilyl group (i.e., R ', R ", R'" is a phenyl group). In some embodiments of the present application, the silicon-containing substituent may be an alkylsilyl group having a total number of carbon atoms of 1 to 10. In some embodiments, R ₅ 、R ₆ 、R ₇ 、R ₈ Independently comprises a number of carbon atoms less than or equal to 6 (i.e. C) ₁ -C ₆ ) Or a silicon-containing substituent. The smaller number of carbon atoms of the hydrocarbon group or the silicon-containing substituent enables the reduction of the metal center M ¹ The surrounding steric hindrance is beneficial to keeping the catalytic activity of the catalyst at a higher level.

The silicon-containing substituent introduced at the carbon position of the cyclopentadiene can react with the metal center M ¹ The synergistic effect is generated, the chain transfer in the polymerization process is promoted, the insertion rate of the cycloolefin monomer is improved, and the cycloolefin copolymer has low molecular weight and moderate glass transition temperature. In some embodiments of the present application, R ₆ Or R ₇ At least one of which is a silicon-containing substituent. The substituents in the 3-and 4-positions of the cyclopentadiene being located further from the metal center M than the substituents in the 2-and 5-positions ¹ Furthermore, silicon-containing substituent groups are introduced into the 3-position and the 4-position of the cyclopentadiene, so that the metal center M can be realized ¹ Weak coordination is formed to promote chain transfer, the molecular weight of the polymer is reduced, and the influence on the polymerization reaction activity of the catalyst due to strong coordination action can be avoided. For example, in one embodiment, R ₆ Is a silicon-containing substituent, R ₅ 、R ₇ And R ₈ Is hydrogen or a hydrocarbyl group. In another embodiment, R ₇ Is a silicon-containing substituent, R ₅ 、R ₆ And R ₈ Is hydrogen or a hydrocarbyl group. In some embodiments, R ₆ And R ₇ Is a silicon-containing substituent, R ₅ And R ₈ Is hydrogen or a hydrocarbyl group.

In the embodiment of the present application, in the formula (1-b), M ² Denotes carbon, silicon, germanium or tin, M ³ Represents carbon, silicon, germanium or tin. M is a group of ² 、M ³ May be the same atom or may be different atoms. M is a group of ² Or M ³ Can be connected with a metal center M ¹ The synergistic effect is generated, the chain transfer in the polymerization process is promoted, the insertion rate of the cycloolefin monomer is improved, and the effects of regulating the molecular weight and the glass transition temperature are achieved, so that the cycloolefin copolymer has low molecular weight and moderate glass transition temperature.

In order to allow the main catalyst shown in the formula (1-b) to realize the effects of adjusting the molecular weight and the glass transition temperature in the preparation process of the cycloolefin copolymer, and finally obtain the cycloolefin copolymer with low molecular weight and moderate glass transition temperature, in the embodiment of the application, the substituent R on the cyclopentadiene ring ₅ 、R ₆ 、R ₇ 、R ₈ Wherein at least one group is a silicon-containing substituent, or at least one of the substituents at the 2-or 7-position of the fluorene ring is a silicon-containing group, i.e. M ² 、M ³ At least one of which is silicon. 2-and 7-positions of the fluorene ring from the metal center M ¹ At moderate distances, the silicon-containing groups in the 2-and 7-positions being spaced from the metal center M ¹ The coordination effect of the catalyst is not too strong or too weak, so that the chain transfer is promoted by the weak coordination effect, the molecular weight of the polymer is reduced, and the influence on the polymerization reaction activity of the catalyst due to the strong coordination effect can be avoided. When M is ² 、M ³ When one or both are silicon, R ₅ 、R ₆ 、R ₇ 、R ₈ All hydrogen atoms or alkyl groups are favorable for ensuring that the polymerization activity is kept at a higher level, better balancing the low molecular weight and the polymerization activity of the polymer, and reducing the preparation difficulty of the catalyst. When M is ² 、M ³ When one or both are silicon, R ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is a silicon-containing group, aSilicon and metal center M ¹ The coordination of (2) can facilitate the preparation of polymers having lower molecular weights.

In some embodiments of the present application, R ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is a silicon-containing substituent, M ² 、M ³ Independently comprises carbon, germanium or tin. In other embodiments of the present application, R ₅ 、R ₆ 、R ₇ 、R ₈ Independently of one another, a hydrogen atom or a hydrocarbon radical, M ² 、M ³ At least one of which is silicon. In other embodiments of the present application, R ₅ 、R ₆ 、R ₇ 、R ₈ At least one of which is a silicon-containing substituent, and M ² 、M ³ At least one of which is silicon. In one embodiment, R ₅ 、R ₆ 、R ₇ 、R ₈ Independently of one another, hydrogen atoms or hydrocarbon radicals, M ² 、M ³ Is silicon, R ₉ 、R ₁₃ 、R ₁₄ 、R ₁₈ The main catalyst of the embodiment can adjust the molecular weight and the glass transition temperature of the copolymer through synergistic action, and has simple structure and easy preparation.

In the embodiments of the present application, R ₁₀ 、R ₁₁ 、R ₁₂ 、R ₁₅ 、R ₁₆ 、R ₁₇ May independently comprise an alkyl, alkoxy, alkenyl, aryl, aryloxy, aralkyl, alkaryl, or aralkenyl group. Specifically, R ₁₀ 、R ₁₁ 、R ₁₂ 、R ₁₅ 、R ₁₆ 、R ₁₇ May independently comprise an alkyl, alkoxy, alkenyl, aryl, aryloxy, aralkyl, alkaryl or aralkenyl group having less than or equal to 10 carbon atoms. In the present embodiment, the alkyl group may be a linear, branched or cyclic alkyl group. The alkyl group may be an unsubstituted alkyl group or a substituted alkyl group. The alkenyl group may be a straight-chain or branched alkenyl group. The alkenyl group may be an unsubstituted alkenyl group or a substituted alkenyl group. The alkoxy group may be a linear, branched or cyclic alkoxy group. In the embodiments of the present application, an alkyl group,The number of carbon atoms of the alkoxy group or alkenyl group may be 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. Specifically, the alkyl group may be, for example, methyl, ethyl, propyl, butyl, or the like. In the embodiments, the aryl group may be an unsubstituted aryl group or a substituted aryl group. The number of carbon atoms of the aryl, aryloxy, aralkyl, alkaryl, aralkenyl group may be 6, 7, 8, 9, 10.

In the embodiment of the present application, in the formula (1-b), R ₉ 、R ₁₃ 、R ₁₄ 、R ₁₈ Independently comprise a hydrogen atom, a hydrocarbyl group or a hydrocarbyloxy group. Specifically, the hydrocarbon group may be an alkyl group, an alkenyl group, an aryl group, an aralkyl group, an alkaryl group or an aralkenyl group having 10 or less carbon atoms (i.e., 1 to 10 carbon atoms). The hydrocarbyloxy group may be an alkoxy group or an aryloxy group having 10 or less carbon atoms (i.e., having 1 to 10 carbon atoms). The alkyl group may be a linear, branched or cyclic alkyl group. The alkyl group may be an unsubstituted alkyl group or a substituted alkyl group. The alkenyl group may be a straight-chain or branched alkenyl group. The alkenyl group may be an unsubstituted alkenyl group or a substituted alkenyl group. The alkoxy group may be a linear, branched or cyclic alkoxy group. In the embodiments of the present application, the number of carbon atoms in the alkyl group, the alkoxy group, or the alkenyl group may be 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. Specifically, the alkyl group may be, for example, a methyl group, an ethyl group, a propyl group, a butyl group, or the like. In the embodiments, the aryl group may be an unsubstituted aryl group or a substituted aryl group. The number of carbon atoms of the aryl, aryloxy, aralkyl, alkaryl, aralkenyl group may be 6, 7, 8, 9, 10. In some embodiments of the present application, R ₉ 、R ₁₃ 、R ₁₄ 、R ₁₈ All hydrogen atoms, namely, substituents are arranged on the carbons at the 2-position and the 7-position on the fluorenyl group, so that the substitution structure on the fluorenyl group can be simpler, and the preparation process of the catalyst is simplified.

In some embodiments of the present application, the catalyst for preparing a cyclic olefin copolymer comprises a main catalyst represented by formula (1-a), and further comprises a cocatalyst, which may be one or more selected from Methylaluminoxane (MAO), modified Methylaluminoxane (MMAO), and an organoboron compound. The organoboron compound may be one or more selected from the group consisting of tris (pentafluorophenyl) boron, triphenylcarbenium tetrakis (pentafluorophenyl) borate, and N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate. The cocatalyst is beneficial to improving the activity of the main catalyst. The use of Modified Methylaluminoxane (MMAO) as cocatalyst may be beneficial in reducing the amount of cycloolefin monomer compared to Methylaluminoxane (MAO). The methyl aluminoxane, the modified methyl aluminoxane and the organic boron compound are used as the cocatalyst, which is beneficial to ensuring the copolymerization reaction activity of the preparation of the cycloolefin copolymer.

In the embodiment of the present application, the catalyst for preparing a cyclic olefin copolymer comprises a main catalyst and a cocatalyst represented by formula (1-a), and the more the amount of the cocatalyst is used, the lower the molecular weight of the cyclic olefin polymer is, and the higher the glass transition temperature is, considering the molecular weight and the glass transition temperature of the cyclic olefin polymer, in the present application, the molar ratio of the main catalyst to the cocatalyst may be 1: (10-10000). In some embodiments, the molar ratio of procatalyst to cocatalyst may be 1: (100-5000). In some embodiments, the molar ratio of procatalyst to cocatalyst can be 1: (500-4000).

In the embodiments of the present application, the catalyst for preparing a cyclic olefin copolymer, which is used for preparing a cyclic olefin copolymer, has high catalytic activity, specifically, catalytic activity higher than 1 × 10 ⁶ g·mol ^-1 ·h ^-1 . In some embodiments, the catalytic activity is greater than 1 × 10 ⁷ g·mol ^-1 ·h ^-1 . The main catalyst shown in the formula (1-a) has high catalytic reaction activity when being used for preparing the cycloolefin copolymer, and is favorable for improving the reaction speed and the conversion rate of the copolymerization reaction.

The compound represented by the above formula (1-b) in the examples of the present application can be prepared in the following manner:

preparation of-X (R) ₃ R ₄ ) -bridged cyclopentadienyl fluorene ligand, lithiated with lithiating reagent, and reacted with M ¹ Metal saltA coordination reaction occurs to obtain a compound represented by the formula (1-b). The reaction process is shown as the reaction formula (A).

The lithiating reagent can be, but is not limited to, n-butyl lithium. M is a group of ¹ The metal salt can be a scandium salt, a titanium salt, a vanadium salt, a zirconium salt, a hafnium salt, a niobium salt or a tantalum salt. The lithiation process may be carried out under anhydrous and oxygen-free, ice bath conditions. The cyclopentadienyl fluorene ligand is leached after lithiation, the obtained product is transferred into a glove box and added with organic solvent and M ¹ The metal salt is stirred overnight to perform the coordination reaction, and the organic solvent may be toluene, hexane, or other solvent capable of dissolving the above product. The product obtained after the coordination reaction can be washed, extracted and recrystallized to obtain the final product.

Taking catalyst a as an example, the specific preparation process of catalyst a may include the following steps:

(1) Preparation of cyclopentadienylfluorene ligand:

under the anhydrous and oxygen-free condition and at the reaction temperature of-78 ℃,2, 7-dibromofluorene and anhydrous tetrahydrofuran are added into a reaction vessel, then a hexane solution containing n-butyllithium is dropwise added, and then trimethylchlorosilane (Me) is dropwise added ₃ SiCl) in tetrahydrofuran, and reacted overnight. Then, a hexane solution containing n-butyllithium and a solution containing triphenylchlorosilane (Ph) were again added dropwise ₃ SiCl) in tetrahydrofuran, and reacted overnight. Then, adding a sodium hydroxide aqueous solution at room temperature for hydrolysis, extracting and separating liquid by using diethyl ether, and drying an organic phase by using anhydrous magnesium sulfate to obtain 2, 7-bis (triphenylsilicon-based) fluorene;

under the anhydrous and oxygen-free conditions, adding the prepared 2, 7-bis (triphenylsilicon-based) fluorene and anhydrous tetrahydrofuran into a reaction vessel, dropwise adding an equimolar amount of methyl lithium ethyl ether solution at room temperature, reacting overnight at room temperature, then dropwise adding an anhydrous tetrahydrofuran solution dissolved with 6, 6-dimethyl fulvene, reacting overnight, adding a tetrabutyl ammonium chloride aqueous solution, stirring, extracting and separating, washing an aqueous phase with ethyl ether for three times, drying an organic phase with anhydrous magnesium sulfate, and drying and recrystallizing to obtain a cyclopentadienyl fluorene ligand precursor.

Adding the above-prepared cyclopentadienylfluorene ligand precursor and anhydrous tetrahydrofuran in a reaction vessel under anhydrous and oxygen-free conditions, adding an equimolar amount of n-butyllithium hexane solution at-78 deg.C, and then dropwise adding trimethylchlorosilane (Me) dropwise ₃ SiCl) was stirred overnight, the solvent was drained and washed with hexane to give the cyclopentadienylfluorene ligand (i.e., catalyst a precursor).

The reaction process of the above step can be seen in the reaction formula (1-1).

(2) Preparation of catalyst a:

adding a cyclopentadienylfluorene ligand (catalyst A precursor) into a reaction vessel under anhydrous and oxygen-free conditions, adding n-butyllithium in an ice bath, removing the ice bath, reacting for 2-12 hours, draining the solvent, transferring into a glove box, adding hexane, adding zirconium tetrachloride under full stirring, and stirring overnight. After the overnight reaction, the reaction mixture was filtered, the filter cake was washed with hexane and dissolved in excess toluene, and the yellowish-brown insoluble matter was filtered off, and then the toluene solution was concentrated and recrystallized to obtain a pink solid catalyst A. The reaction process of this step can be seen in the reaction formula (1-2).

In the embodiment of the present application, the preparation of the catalyst having another structure represented by the formula (1-b) can be referred to the preparation of the catalyst a, and will not be described one by one here.

The embodiment of the present application also provides a method for preparing a cyclic olefin copolymer, which uses the catalyst for preparing a cyclic olefin copolymer described in the embodiment of the present application, and the method comprises:

in the presence of the catalyst for preparing the cycloolefin copolymer, a cycloolefin monomer and ethylene or alpha-olefin are subjected to copolymerization reaction to obtain the cycloolefin copolymer.

In the embodiment of the application, the reaction system of the copolymerization comprises an inert solvent, and the inert solvent comprises one or more of straight-chain alkane compounds, cyclic hydrocarbon compounds and aromatic hydrocarbon compounds. The linear alkane compound may specifically be a linear alkane having 5 to 16 carbon atoms, for example, pentane, hexane, heptane, octane, or the like. The cyclic hydrocarbon compound may specifically be a cyclic hydrocarbon having 5 to 11 carbon atoms, for example, cyclopentane, cyclohexane, etc. The aromatic hydrocarbon compound may specifically be a liquid aromatic hydrocarbon having 6 to 20 carbon atoms, such as toluene.

In the embodiment of the present application, the amount of the procatalyst represented by formula (1-a) in the copolymerization reaction system is 0.001mmol/L to 10mmol/L. In some embodiments, the amount of the main catalyst represented by formula (1-a) in the reaction system for copolymerization is 0.01mmol/L to 1mmol/L. In some embodiments, the amount of the main catalyst represented by formula (1-a) in the copolymerization reaction system is 0.01mmol/L to 0.1mmol/L.

In the embodiment of the present application, the molar ratio of the main catalyst represented by formula (1-a) to the cocatalyst in the copolymerization reaction system may be 1: (10-10000). In some embodiments, the molar ratio of procatalyst to cocatalyst may be 1: (100-5000). In some embodiments, the molar ratio of procatalyst to cocatalyst may be 1: (500-4000).

In the embodiment of the present application, the amount of the cycloolefin monomer used in the reaction system for copolymerization may be 0.01mol/L to 10mol/L. In some embodiments, the amount of the cycloolefin monomer used in the copolymerization reaction system may be in the range of 0.01mol/L to 5mol/L. In some embodiments, the amount of the cycloolefin monomer used in the copolymerization reaction system may be 0.01mol/L to 1mol/L.

In the embodiment of the present application, the molar ratio of the cyclic olefin monomer to the main catalyst in the copolymerization reaction system is 500 to 500000. In some embodiments, the molar ratio of the cyclic olefin monomer to the procatalyst in the copolymerization reaction system is from 1000 to 100000. In some embodiments, the molar ratio of the cycloolefin monomer to the procatalyst in the copolymerization reaction system is from 5000 to 100000. The main catalyst can adapt to the usage amount of cycloolefin monomers in a larger range, and has high catalytic activity.

In the embodiment of the present application, the temperature of the copolymerization reaction may be 50 ℃ to 120 ℃; the time of the copolymerization reaction can be 2min to 10min. By adopting the catalyst for copolymerization, the reaction temperature is mild, the time is short, and the polymerization process can be optimized. In some embodiments, the temperature of the copolymerization reaction may be from 60 ℃ to 110 ℃. In some embodiments, the temperature of the copolymerization reaction may be from 80 ℃ to 100 ℃. In some embodiments, the time for the copolymerization reaction may be 3min to 6min.

In the embodiment of the present application, the structural formula of the cycloolefin monomer may be as shown in formula (2):

in the formula (2), R ₁₉ Is a hydrocarbyl or a hydrocarbyl silyl group; r ₂₀ And R ₂₁ Each independently comprises a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, an atom or an atomic group which may substitute for the above group;

R ₂₂ and R ₂₃ Each independently comprises a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, an atom or atom group which may be substituted for the above groups, or R ₂₂ And R ₂₃ Linked to form a group having a cyclic structure;

z is a positive integer.

In the embodiments of the present application, R ₁₉ Is a hydrocarbyl or hydrocarbylsilyl group, and the hydrocarbyl group may be an alkylene group, an alkenylene group, an arylene group, an aralkylene group, an alkarylene group, or an aralkylene group. The number of carbon atoms of the hydrocarbon group may be 10 or less (i.e., the number of carbon atoms is 1 to 10). Specifically, the number of carbon atoms of the alkylene group or alkenylene group may be 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10. The number of carbon atoms of the arylene group, aralkylene group, alkarylene group, and aralkylene group may be 6, 7, 8, 9, or 10. The hydrocarbyl silyl group may be an alkylsilylene group or an arylsilyl group.The number of carbon atoms of the hydrocarbyl silicon group may be less than or equal to 10 (i.e., from 1 to 10 carbon atoms). In some embodiments, the hydrocarbyl silyl group may specifically be a dimethylsilylene group (-Si (CH) ₃ ) ₂ -, diethylsilylene (-Si (C) ₂ H ₅ ) ₂ -, diphenylsilylene (-Si (C) ₆ H ₅ ) ₂ -) and the like.

In the embodiments of the present application, the atom or atom group that may be substituted for the above group means an atom or atom group that may be substituted for a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an alkoxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, and specifically, for example, an isotope atom (deuterium or the like) of a hydrogen atom, borane, a metal ligand, or the like.

In the embodiments of the present application, R ₂₀ 、R ₂₁ 、R ₂₂ And R ₂₃ In (1), the halogen atom may be fluorine, chlorine, bromine or iodine. The alkyl group may be an alkyl group having 1 to 20 carbon atoms. In some embodiments, the number of carbon atoms in the alkyl group is from 2 to 10; in other embodiments, the number of carbon atoms in the alkyl group is from 8 to 20; in other embodiments, the number of carbon atoms in the alkyl group is from 8 to 15. The alkyl group may be a linear, branched or cyclic alkyl group. Specifically, the alkyl group may be, for example, a methyl group, an ethyl group, a propyl group, a butyl group, or the like. The alkyl group may be an unsubstituted alkyl group or a substituted alkyl group. In the embodiment of the present invention, the aromatic group may be an aromatic group having 6 to 20 carbon atoms, and further, the number of carbon atoms of the aromatic group may be 6 to 10; further, the number of carbon atoms of the aromatic group may be 7 to 8. The aromatic group may be an unsubstituted aromatic group or a substituted aromatic group. In the embodiment of the present application, the number of carbon atoms of the alkoxy group may be 1 to 20. In some embodiments, the alkoxy group has from 2 to 10 carbon atoms; in other embodiments, the alkoxy group has from 8 to 20 carbon atoms; in other embodiments, the alkoxy group has from 8 to 15 carbon atoms. The alkoxy group may be a linear, branched or cyclic alkoxy group.

In the embodiments of the present application, R ₂₂ 、R ₂₃ The cyclic structure formed by connection can be a saturated or unsaturated carbocycle, a saturated or unsaturated heterocycle, a heterocycleThe hetero atom in (b) may be nitrogen, sulfur, oxygen, boron, silicon, etc. For example, R ₂₂ 、R ₂₃ The group attached to the ring structure formed by the attachment may be an atom or a group of atoms including a hydrogen atom, a halogen atom, an alkyl group, an aromatic group, an alkoxy group, a hydroxyl group, an ester group, a cyano group, an amino group, a thiol group, and a substituent for the above group.

In the embodiment of the present application, z is a positive integer, and specifically may be 1, 2, 3, 4, or the like.

In the present embodiment, the α -olefin is a monoolefin having a double bond at the terminal of the molecular chain, and the number of carbon atoms of the α -olefin may be 2 to 20. Specifically, the α -olefin may be propylene, 1-butene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene or 2-ethyl-1-butene.

In the embodiment of the present application, the copolymerization reaction system does not contain a molecular weight modifier. The method for preparing a cycloolefin copolymer according to the embodiment of the present application can achieve the effect of adjusting the molecular weight only by the catalyst for cycloolefin preparation provided in the embodiment of the present application, and a cycloolefin copolymer having a low molecular weight can be obtained.

In the present embodiment, taking the copolymerization of the cycloolefin monomer and ethylene as an example, the reaction process for preparing the cycloolefin copolymer can be as shown in the reaction formula (1-3):

according to the preparation method of the cycloolefin copolymer provided by the embodiment of the application, by adopting the catalyst provided by the embodiment of the application, the cycloolefin copolymer with low molecular weight and moderate glass transition temperature can be prepared without additionally introducing molecular weight regulators such as hydrogen or propylene, so that the requirements of processing performance, heat resistance and the like of various optical products such as optical lenses and the like, display materials, packaging materials and other products are met, meanwhile, other properties such as optical performance, thermal performance, mechanical performance and the like of the cycloolefin copolymer are kept at the same level as those of the traditional low molecular weight cycloolefin copolymer material,therefore, the low molecular weight cycloolefin copolymer material produced by the method can be suitable for the application scene of the traditional cycloolefin copolymer material. The preparation method not only greatly simplifies the preparation approach of the cycloolefin copolymer material, but also obviously improves the polymerization activity and the energy and economic benefits, and opens up a new path for producing the cycloolefin copolymer material on a large scale. The polymerization reaction of the cycloolefin monomer and the alpha-olefin in the embodiment of the application has higher activity. Experimental results show that the cycloolefin copolymer prepared by the method in the embodiment of the application has moderate T _g (110-180 ℃) and lower molecular weight (less than or equal to 15 ten thousand), the insertion rate of the cycloolefin monomer is between 20 percent and 60 percent, and the molecular weight distribution index is between 1.5 and 3.0.

The embodiment of the application also provides a cycloolefin copolymer prepared by the method, and the structural formula of the cycloolefin copolymer is shown as a formula (3):

in the formula (3), R ₁₉ Is hydrocarbyl or hydrocarbyl silyl; r is ₂₀ And R ₂₁ Each independently includes a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, an atom or an atomic group which may substitute the above groups;

R ₂₂ 、R ₂₃ 、R ₂₄ 、R ₂₅ each independently comprises a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, an atom or atom group which may be substituted for the above groups, or R ₂₂ And R ₂₃ Linked to form a group having a cyclic structure, R ₂₄ And R ₂₅ Linked to form a group having a cyclic structure;

x and y represent polymerization degrees, both x and y are positive numbers, 1 < x: y < 3, and z is a positive integer.

Understandably, the cycloolefin polymer shown in the formula (3) in the examples of the present application, wherein R is ₁₉ 、R ₂₀ 、R ₂₁ 、R ₂₂ 、R ₂₃ And R in the cycloolefin monomer represented by the formula (2) ₁₉ 、R ₂₀ 、R ₂₁ 、R ₂₂ 、R ₂₃ The specific selection is consistent, and the details are not repeated here.

In the embodiments of the present application, R ₂₄ 、R ₂₅ The halogen atom may be fluorine, chlorine, bromine or iodine. The alkyl group may be an alkyl group having 1 to 20 carbon atoms. In some embodiments, the number of carbon atoms in the alkyl group is from 2 to 10; in other embodiments, the number of carbon atoms in the alkyl group is from 8 to 20; in other embodiments, the alkyl group has from 8 to 15 carbon atoms. The alkyl group may be a linear, branched or cyclic alkyl group. Specifically, the alkyl group may be, for example, a methyl group, an ethyl group, a propyl group, a butyl group, or the like. The alkyl group may be an unsubstituted alkyl group or a substituted alkyl group. In the embodiment, the aryl group may be an aromatic group having 6 to 20 carbon atoms, and further, the carbon number of the aryl group may be 6 to 10; further, the number of carbon atoms of the aryl group may be 7 to 8. The aryl group may be an unsubstituted aromatic group or a substituted aromatic group. In the embodiment of the present application, the number of carbon atoms of the alkoxy group may be 1 to 20. In some embodiments, the alkoxy group has from 2 to 10 carbon atoms; in other embodiments, the alkoxy group has from 8 to 20 carbon atoms; in other embodiments, the alkoxy group has from 8 to 15 carbon atoms. The alkoxy group may be a linear, branched or cyclic alkoxy group.

In the embodiments of the present application, R ₂₄ 、R ₂₅ The cyclic structure formed by the connection can be a saturated or unsaturated carbon ring, a saturated or unsaturated heterocyclic ring, and the heteroatoms in the heterocyclic ring can be nitrogen, sulfur, oxygen, boron, silicon and the like. For example, R ₂₄ 、R ₂₅ The group bonded to the ring structure formed by bonding may be an atom or an atom group including a hydrogen atom, a halogen atom, an alkyl group, an aromatic group, an alkoxy group, a hydroxyl group, an ester group, a cyano group, an amino group, a thiol group, and a substituent for the above groups.

In the embodiments of the present application, z is a positive integer, and specifically may be 1, 2, 3, 4, or the like. The ratio of x to y may be 1.5 < x: y < 2.5.

In the embodiments of the present application, the weight average molecular weight of the cycloolefin copolymer is less than or equal to 150000; the molecular weight distribution index is in the range of 1.5 to 3.0. In some embodiments, the cycloolefin copolymer has a weight average molecular weight in a range of 5000 to 150000; in some embodiments, the cycloolefin copolymer has a weight average molecular weight in a range of 10000 to 120000. In some embodiments, the weight average molecular weight of the cyclic olefin copolymer is in the range of 20000 to 100000. The cycloolefin copolymer has relatively low weight average molecular weight and better processing performance, and is favorable for improving commercial value. In some embodiments, the molecular weight distribution index is in the range of 1.7 to 2.4.

In some embodiments of the present application, the insertion rate of the cycloolefin monomers is between 20% and 60%; in some embodiments, the insertion rate of the cyclic olefin monomer is between 20% and 50%; in some embodiments, the insertion rate of the cyclic olefin monomer is between 30% and 40%. The suitable insertion rate of the cycloolefin monomer enables the cycloolefin polymer to have a suitable glass transition temperature. In some embodiments of the present application, the glass transition temperature of the cyclic olefin copolymer is in the range of 110 ℃ to 180 ℃. In some embodiments, the glass transition temperature of the cyclic olefin copolymer is in the range of 120 ℃ to 160 ℃. In some embodiments, the glass transition temperature of the cyclic olefin copolymer is in the range of 130 ℃ to 150 ℃. The glass transition temperature is within the range of 120 ℃ to 160 ℃, so that excellent processing and forming performance can be obtained, and the copolymer product can be used under the condition of higher environmental temperature, thereby better considering both the processing performance and the use condition.

In the embodiment of the present application, the molded article of the cycloolefin copolymer has a visible light transmittance of more than 90%. The molded body may be a sheet-like molded body formed by hot pressing; or a film-like molded body formed by coating; the thickness of the shaped body may be in the range of 0.1mm to 1 mm.

In this application, "-" denotes a range, including two endpoints. For example, the amount of the procatalyst used in the copolymerization reaction system is from 0.001mmol/L to 10mmol/L, which means that the amount of the procatalyst used is any value in the range of from 0.001mmol/L to 10mmol/L, inclusive.

Also provided in the examples herein is a composition comprising the cyclic olefin copolymer described above in the examples herein. The composition can be used as an optical material.

In an embodiment of the present application, the composition further comprises an additive, which may be one or more of a filler, a dye, an antioxidant, a light stabilizer, an ultraviolet absorber, a plasticizer, a flame retardant, an antistatic agent, and a mold release agent. The composition may further include other polymers, which may be other cyclic olefin polymers or acyclic olefin polymers different from the examples of the present application, and may be added in a proper amount as required. In the composition, the mass content of the cycloolefin polymer described above in the examples of the present application may be 60% or more. In some embodiments, the mass content of the cycloolefin polymer according to the embodiment may be 60%, 70%, 80%, 90%, 95%, 98%.

Embodiments also provide an optical article that includes the cyclic olefin copolymer described above in embodiments. The above cycloolefin copolymer or the composition can be processed into an optical article by various known molding methods. The optical product can be made by locally processing the cycloolefin copolymer or the composition, or can be made by processing the cycloolefin copolymer or the optical material in a whole.

In embodiments of the present application, the optical article may specifically include an optical lens, an optical film, an optical disc, a light guide plate, or a display panel.

In the embodiments of the present application, the optical lens may specifically include a spectacle lens, a camera lens, a sensor lens, an illumination lens, an imaging lens, and the like. The camera lens can be a mobile phone camera lens, a notebook computer camera lens, a desktop camera lens, an automobile camera lens, and the like. The spectacle lenses may include, among others, myopic lenses, presbyopic lenses, sunglass lenses, contact lens corrective lenses, goggle lenses, and the like. The sensor lens may be a motion detector lens, a proximity sensor lens, an attitude control lens, an infrared sensor lens, or the like. Among them, the illumination lens may be an indoor illumination lens, an outdoor illumination lens, a vehicle headlamp lens, a vehicle fog lens, a vehicle backlight lens, a vehicle running light lens, a vehicle fog lens, a vehicle interior lens, a Light Emitting Diode (LED) lens, an Organic Light Emitting Diode (OLED) lens, or the like. Among them, the imaging lens may be a scanner lens, a projector lens, a telescope lens, a microscope lens, a magnifier lens, or the like.

In the embodiments of the present disclosure, the optical film may include a light guide film, a reflective film, an antireflection film, a diffusion film, a light filter film, a polarizing film, a light splitting film, a phase film, and the like. The optical film can be used in the display field, the illumination field, and the like, and can be used, for example, as a film for a liquid crystal substrate.

Referring to fig. 1, the present application also provides an apparatus 100 including the optical article of the present application. The device 100 may be an electronic device, and specifically may include a mobile terminal, glasses, a camera, a vehicle (e.g., an automobile, a motorcycle, a train, etc.), an illumination device (e.g., a table lamp, a ceiling lamp, a street lamp, etc.), an imaging device (e.g., an endoscope, a microscope, a telescope, a projector, a scanner, etc.), a security device, and the like. The mobile terminal may specifically include various handheld devices (such as various mobile phones, tablet computers, mobile notebooks, netbooks) with wireless communication functions, wearable devices (such as a smart watch), or other processing devices connected to the wireless modem, and various forms of User Equipment (UE), a Mobile Station (MS), a terminal device (terminal device), and the like. Equipment 100 includes camera module 2, and camera module 2 includes the camera lens, and the camera lens adopts the above-mentioned cyclic olefin copolymer preparation of this application embodiment. The device 100 further comprises a camera protection cover plate 103 covering the camera lens.

In a specific embodiment of the present application, the device 100 is a mobile terminal, and the mobile terminal includes a camera module, and the camera module includes a camera lens, and the camera lens is prepared by using the above cyclic olefin copolymer of the embodiment of the present application.

In a specific embodiment of the present application, the apparatus 100 is an endoscope, and the endoscope includes a camera module, and the camera module includes a camera lens, and the camera lens is prepared by using the cyclic olefin copolymer described in the embodiment of the present application.

In a specific embodiment of the present application, the apparatus 100 is a vehicle, the vehicle includes a camera module, the camera module includes a camera lens, and the camera lens is prepared by using the above cyclic olefin copolymer of the embodiment of the present application.

In a specific embodiment of this application, equipment 100 is security protection equipment, and security protection equipment includes the camera module, and the camera module includes the camera lens, and the camera lens adopts the above-mentioned cyclic olefin copolymer preparation of this application embodiment.

The examples of the present application are further illustrated below in various examples.

Example 1

Preparing a catalyst:

(1a) 5mmol of 2, 7-dibromofluorene and 50mL of anhydrous tetrahydrofuran are added dropwise at a reaction temperature of-78 ℃ in a 100mL reaction vessel under anhydrous and oxygen-free conditions, a hexane solution containing 10mmol of n-butyllithium is subsequently added dropwise, and 10mmol of trimethylchlorosilane (Me) is subsequently added dropwise ₃ SiCl) in tetrahydrofuran, and reacted overnight. Then, a hexane solution containing 10mmol of n-butyllithium and a hexane solution containing 10mmol of triphenylchlorosilane (Ph) were again added dropwise ₃ SiCl) in tetrahydrofuran, and reacted overnight. Subsequently, 50mL of a 0.5mol/L aqueous solution of sodium hydroxide was added thereto at room temperature for hydrolysis, followed by extraction with diethyl ether and drying of the organic phase over anhydrous magnesium sulfate to give 2, 7-bis (triphenylsilyl) fluorene.

(1b) Under the anhydrous and oxygen-free conditions, 5mmol of prepared 2, 7-bis (triphenylsilicon-based) fluorene and 50mL of anhydrous tetrahydrofuran are added into a 100mL reaction vessel, an equimolar amount of methyl lithium ethyl ether solution (1.4 mol/L) is dropwise added at room temperature for overnight reaction at room temperature, then 20mL of anhydrous tetrahydrofuran solution dissolved with 5mmol of 6, 6-dimethyl fulvene is dropwise added for reaction overnight, 100mL of tetrabutylammonium chloride aqueous solution is added for stirring for 10min, extraction and liquid separation are carried out, 50mL of ethyl ether is used for washing an aqueous phase for three times, and after an organic phase is dried by anhydrous magnesium sulfate, the drying and recrystallization are carried out to obtain the cyclopentadienyl fluorene ligand precursor.

(1c) Adding 5mmol of the mixture into a 100mL reaction vessel under anhydrous and oxygen-free conditionsThe cyclopentadienyl fluorene ligand precursor prepared above and 50mL of anhydrous tetrahydrofuran were added with an equimolar amount of n-butyllithium hexane solution at-78 deg.C, followed by dropwise addition of trimethylchlorosilane (Me) ₃ SiCl) 5mL, stirred overnight, the solvent was drained and washed 1-3 times with hexane to give catalyst a precursor.

(1d) Under anhydrous and anaerobic conditions, 1g of catalyst A precursor was added to a 100mL reaction vessel, 3.4mL n-butyllithium was added at 0 ℃ reaction temperature, the temperature was slowly raised to room temperature, the reaction was carried out for 2 to 12 hours, the solvent was drained, the reaction vessel was transferred to a glove box, hexane was added thereto, and 0.6g of zirconium tetrachloride was added thereto under thorough stirring, and the mixture was stirred overnight. After the overnight reaction, the reaction mixture was filtered, the filter cake was washed with hexane and dissolved in excess toluene, and the yellowish-brown insoluble matter was filtered off, and then the toluene solution was concentrated and recrystallized to obtain a pink solid catalyst A. The pink solid catalyst A obtained in this example was 0.3g, the yield was 19.7%, the purity was 93.5%, and FIG. 2 shows the NMR spectrum of catalyst A. FIG. 3 is a NMR carbon spectrum of catalyst A. The nmr hydrogen spectrum of fig. 2 and the nmr carbon spectrum of fig. 3 indicate that catalyst a was successfully prepared.

Preparation of cycloolefin monomer: 78g of dicyclopentadiene, 110g of norbornene and a small amount of 2, 6-dimethoxyphenol (BHT) are sequentially added into a 220mL autoclave, the mixture is heated and reacted at 220 ℃ for 24 hours under the atmosphere of nitrogen, the temperature of a reaction system is reduced to room temperature after the reaction is finished, the mixture is directly distilled under reduced pressure, the previous fraction is unreacted dicyclopentadiene, the subsequent fraction is a target product of a cycloolefin monomer, and the reaction process is shown as a reaction formula (1-4). The cycloolefin monomer obtained in this example was 128g of colorless liquid, and the yield was 67%, FIG. 4 is the NMR spectrum of the cycloolefin monomer of this example; FIG. 5 shows the NMR carbon spectrum of the cycloolefin monomer according to example 1 of the present application. The hydrogen nuclear magnetic resonance spectrum of fig. 4 and the carbon nuclear magnetic resonance spectrum of fig. 5 indicate that the cycloolefin monomer was successfully prepared.

Preparation of cycloolefin copolymer: a glass reactor containing 2.5g of the above cycloolefin monomer, 2.5mL of MAO solution (1.5 mol/L in toluene) and 45mL of toluene was placed in an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and the glass reactor was stirred to saturate the toluene solution in the glass reactor with ethylene, the polymerization temperature was adjusted to 90 ℃ C, 2.0mg of 2mL of a toluene solution of the catalyst A prepared in this example was added, the ethylene pressure was adjusted and maintained at one atmospheric pressure, and polymerization was carried out for 5 minutes. After the polymerization is finished, pouring the obtained reaction solution into a 10% hydrochloric acid aqueous solution, fully stirring, separating the solution, and washing an organic layer twice with water; and (3) fully stirring the obtained organic layer with acetone, settling, filtering, adding a proper amount of acetone, refluxing for 2 hours, finally filtering the polymer, washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white cyclic olefin copolymer material. The polymerization process is shown in the reaction formula (1-5). FIG. 6 shows NMR spectra of cycloolefin copolymer according to example 1 of the present application; FIG. 7 shows the NMR carbon spectrum of the cycloolefin copolymer according to example 1 of the present application. In fig. 7 a) is an enlarged view of the dashed area. The NMR hydrogen spectrum of FIG. 6 and the NMR carbon spectrum of FIG. 7 indicate that the cycloolefin polymer was successfully prepared.

The mass of the cycloolefin copolymer material obtained in this example was 2.4g, and the polymerization activity of the catalyst was 1.4X 10 ⁷ g mol ^-1 h ^-1 . The cycloolefin copolymer material was determined by high temperature gel chromatography to have a relative number average molecular weight of 26kg/mol (weight average molecular weight of 62.4 kg/mol) and a molecular weight distribution index of 2.4 (molecular weight distribution index equals weight average molecular weight divided by number average molecular weight). The cyclic olefin copolymer obtained was detected by high-temperature nuclear magnetic carbon spectrometry, and the result indicates that the insertion rate of the cyclic olefin monomer of the COC material prepared in this example is 33%, and the insertion rate = (y/(x + y)) = 100%. Copolymerization of the resulting cycloolefins by Differential Scanning Calorimetry (DSC)The glass transition temperature of the material is detected, and fig. 8 is a DSC curve of the cycloolefin copolymer of example 1, and the result shows that the glass transition temperature of the cycloolefin copolymer prepared in this example is 141.02 ℃, and fig. 8 also shows that no crystallization peak appears in the DSC curve, because the insertion rate of the cycloolefin monomer of the COC material is increased by using the main catalyst of the example, which is in favor of avoiding the generation of a crystalline polyethylene segment. The cycloolefin copolymer prepared in the embodiment of the present application is molded into a film or sheet sample with a thickness of 0.1mm to 1mm, and through detection, the visible light transmittance of the cycloolefin copolymer film or sheet sample prepared in the embodiment is greater than 90%, and fig. 9 is a visible light transmittance test curve of the cycloolefin copolymer prepared in the embodiment 1 of the present application.

Compared with the prior art, the preparation method has the advantages that an external molecular weight regulator is not needed, the catalyst A is adopted, the preparation of the low-molecular-weight cycloolefin copolymer material can be directly realized, and other excellent properties of the cycloolefin copolymer material are ensured.

Example 2

The synthesis procedure of the catalyst and the cycloolefin monomer was the same as in example 1.

Preparation of cycloolefin copolymer: a glass reactor containing 3.5g of cycloolefin monomer, 2.5mL of MAO (1.5 mol/L in toluene) and 45mL of toluene was placed in an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and the glass reactor was stirred to saturate the toluene solution in the glass reactor with ethylene, the polymerization temperature was adjusted to 90 ℃ and 2mL of a toluene solution of 2.0mg of catalyst A was added, the ethylene pressure was adjusted and maintained at one atmosphere, and polymerization was carried out for 5 minutes. After the polymerization is completed, pouring the obtained reaction solution into a 10% hydrochloric acid aqueous solution, fully stirring, separating the solution, and washing the organic layer twice with water; and (3) fully stirring the obtained organic layer with acetone for settling, filtering, adding an appropriate amount of acetone for refluxing for 2 hours, finally filtering the polymer, washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white cyclic olefin copolymer material.

The cycloolefin copolymer obtained in this example had a mass of 3.28g and the polymerization activity of the catalyst was 1.9X 10 ⁷ g mol ^-1 h ^-1 . The cycloolefin copolymer was determined by high-temperature gel chromatography to have a relative number-average molecular weight of 58kg/mol (weight-average molecular weight of 98.6 kg/mol) and a molecular weight distribution index of 1.7. The obtained cycloolefin copolymer was detected by high-temperature nuclear magnetic carbon spectrum, and the result showed that the insertion rate of the cycloolefin monomer in the cycloolefin copolymer material prepared in this example was 38%. The glass transition temperature of the resulting cycloolefin copolymer was measured by Differential Scanning Calorimetry (DSC), and FIG. 10 is a DSC curve of the cycloolefin copolymer of example 2 herein, and it was found that the glass transition temperature of the cycloolefin copolymer was 141.43 ℃. Through detection, the visible light transmittance of the cycloolefin copolymer prepared by the embodiment is more than 90%.

Compared with example 1, example 2 increases the amount of cycloolefin monomer, and it can be seen from examples 1 and 2 that the preparation of low molecular weight and suitable glass transition temperature COC can be realized by using the procatalyst of the examples of the present application in a wide range of monomer concentration.

Example 3

The procedure for synthesizing the catalyst and cycloolefin monomer was the same as in example 1.

Preparation of cycloolefin copolymer: a glass reactor containing 2.5g of cycloolefin monomer, 2.6mL of MMAO solution (8% by weight in heptane) and 45mL of toluene was charged into an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and stirred to saturate the toluene solution in the glass reactor with ethylene, the polymerization temperature was adjusted to 90 ℃ and 2mL of a toluene solution of 2.0mg of catalyst A was added, the pressure of ethylene was adjusted and maintained at one atmosphere, and polymerization was carried out for 5 minutes. After the polymerization is completed, pouring the obtained reaction solution into a 10% hydrochloric acid aqueous solution, fully stirring, separating the solution, and washing the organic layer twice with water; and (3) fully stirring the obtained organic layer with acetone for settling, filtering, adding an appropriate amount of acetone for refluxing for 2 hours, finally filtering the polymer, washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white cyclic olefin copolymer.

The mass of the cycloolefin copolymer obtained in this example was 2.97g, and the polymerization activity of the catalyst was 1.8X 10 ⁷ g mol ^-1 h ^-1 . The cycloolefin copolymer material obtained in this example was determined by high-temperature gel chromatography to have a relative number-average molecular weight of 35kg/mol (weight-average molecular weight of 84 kg/mol) and a molecular weight distribution index of 2.4. The high-temperature nuclear magnetic carbon spectrum is adopted to detect the obtained cycloolefin copolymer, and the result shows that the insertion rate of the cycloolefin monomer of the cycloolefin copolymer material prepared in the embodiment is 30%. The glass transition temperature of the resultant cycloolefin copolymer was measured by Differential Scanning Calorimetry (DSC), and FIG. 11 is a DSC curve of the cycloolefin copolymer of example 3 of the present application, which showed that the glass transition temperature of the cycloolefin copolymer prepared in this example was 129.81 ℃. The cyclic olefin copolymer prepared in this example has a visible light transmittance of more than 90%.

Example 3 compared with example 1 by changing the cocatalyst, from example 1 and example 3, it can be seen that the catalyst a of the present example can be used as the main catalyst, and when different cocatalysts are used, the preparation of low molecular weight COC suitable for glass transition temperature can be realized.

Example 4

Preparation of cycloolefin copolymer: a glass reactor containing 3.5g of cycloolefin monomer, 2.6mL of MMAO (8% by weight of heptane) and 45mL of toluene was placed in an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and stirred to saturate the toluene solution in the glass reactor with ethylene, the polymerization temperature was adjusted to 90 ℃ and 1.2mg of the catalyst prepared in the present invention in 2mL of toluene solution was added, the pressure of ethylene was adjusted and maintained at one atmosphere, and the polymerization was carried out for 5 minutes. After the polymerization is completed, pouring the obtained reaction solution into a 10% hydrochloric acid aqueous solution, fully stirring, separating the solution, and washing the organic layer twice with water; and (3) fully stirring the obtained organic layer with acetone for settling, filtering, adding an appropriate amount of acetone for refluxing for 2 hours, finally filtering the polymer, washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white cyclic olefin copolymer material.

The cycloolefin copolymer prepared in this example had a mass of 196g, polymerization activity of catalyst 1.2 x 10 ⁷ g mol ^-1 h ^-1 . The cycloolefin copolymer material obtained in this example was determined by high-temperature gel chromatography to have a relative number-average molecular weight of 26kg/mol (weight-average molecular weight of 62.4 kg/mol) and a molecular weight distribution index of 2.4. The insertion rate of the cycloolefin monomer is 39% by detecting the obtained cycloolefin copolymer by adopting a high-temperature nuclear magnetic carbon spectrum. The glass transition temperature of the resultant cycloolefin copolymer was measured by Differential Scanning Calorimetry (DSC), and FIG. 12 is a DSC curve of the cycloolefin copolymer of example 4 of the present application, and it was found that the glass transition temperature of the cycloolefin copolymer material prepared in this example was 145.67 ℃. Through detection, the visible light transmittance of the cycloolefin copolymer prepared by the embodiment is more than 90%.

Compared with the embodiment 1, the embodiment 4 changes the use amounts of the cocatalyst and the cycloolefin monomer, and the result shows that the main catalyst provided by the embodiment of the application can realize the preparation of the low molecular weight and the suitable glass transition temperature COC by simultaneously changing the use amounts of the cocatalyst and the cycloolefin monomer, and the main catalyst provided by the embodiment of the application has a wide application range and a good effect.

Example 5

Preparing a catalyst:

(1a) 5mmol of 2, 7-dibromofluorene and 50mL of anhydrous tetrahydrofuran are added dropwise at a reaction temperature of-78 ℃ in a 100mL reaction vessel under anhydrous and oxygen-free conditions, a hexane solution containing 10mmol of n-butyllithium is subsequently added dropwise, and 10mmol of trimethylchlorosilane (Me) is subsequently added dropwise ₃ SiCl) in tetrahydrofuran, and reacted overnight. Then, a hexane solution containing 10mmol of n-butyllithium and a hexane solution containing 10mmol of trimethylchlorosilane (Me) were again added dropwise ₃ SiCl) in tetrahydrofuran, and reacted overnight. Subsequently, 50mL of a 0.5mol/L aqueous solution of sodium hydroxide was added at room temperature to conduct hydrolysis, the liquid separation was extracted with diethyl ether, and the organic phase was dried over anhydrous magnesium sulfate to obtain 2, 7-bis (trimethylsilyl) fluorene.

(1b) To (1 d) are the same as in example 1.

The procedure for the synthesis of cycloolefin monomers was the same as in example 1.

Preparation of cycloolefin copolymer: a glass reactor containing 2.5g of cycloolefin monomer, 2.5mL of MAO (1.5 mol/L in toluene) and 45mL of toluene was placed in an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and the glass reactor was stirred to saturate the toluene solution in the glass reactor with ethylene, the polymerization temperature was adjusted to 90 ℃ C, 1.3mg of catalyst B in 2mL of toluene was added, the ethylene pressure was adjusted and maintained at one atmosphere, and polymerization was carried out for 5 minutes. After the polymerization is completed, pouring the obtained reaction solution into a 10% hydrochloric acid aqueous solution, fully stirring, separating the solution, and washing the organic layer twice with water; and (3) fully stirring the obtained organic layer with acetone for settling, filtering, adding an appropriate amount of acetone for refluxing for 2 hours, finally filtering the polymer, washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white cyclic olefin copolymer material.

The cycloolefin copolymer obtained in this example had a mass of 1.99g and the polymerization activity of the catalyst was 1.2X 10 ⁷ g mol ^-1 h ^-1 . The cycloolefin copolymer material obtained in this example was determined by high temperature gel chromatography to have a relative number average molecular weight of 35kg/mol (weight average molecular weight of 70 kg/mol) and a molecular weight distribution index of 2.0. The insertion rate of the cycloolefin monomer is 31 percent by detecting the obtained cycloolefin copolymer by adopting a high-temperature nuclear magnetic carbon spectrum. The glass transition temperature of the resultant cyclic olefin copolymer was measured by Differential Scanning Calorimetry (DSC), and FIG. 13 is a DSC curve of the cyclic olefin copolymer of example 5 herein, and it was found that the glass transition temperature of the cyclic olefin copolymer material prepared in this example was 131.51 ℃. The cyclic olefin copolymer prepared in this example has a visible light transmittance of more than 90%.

Example 6

Preparing a catalyst:

(1a) Adding 5mmol of 2, 7-dibromofluorene and 50mL of anhydrous tetrahydrofuran into a 100mL reaction vessel at-78 ℃ under anhydrous and oxygen-free conditions, dropwise adding a hexane solution containing 10mmol of n-butyllithiumThen dropwise adding 10mmol of trimethylchlorosilane (Me) ₃ SiCl) in tetrahydrofuran, and reacted overnight. Then, a hexane solution containing 10mmol of n-butyllithium and a hexane solution containing 10mmol of triethylchlorosilane (Et) were again added dropwise ₃ SiCl) in tetrahydrofuran, and reacted overnight. Subsequently, 50mL of a 0.5mol/L aqueous solution of sodium hydroxide was added thereto at room temperature for hydrolysis, followed by extraction with diethyl ether and drying of the organic phase over anhydrous magnesium sulfate to give 2, 7-bis (triethylsilyl) fluorene.

(1b) To (1 d) are the same as in example 1.

Preparation of cycloolefin copolymer: a glass reactor containing 2.5g of cycloolefin monomer, 2.5mL of MAO (1.5 mol/L toluene solution) and 45mL of toluene was placed in an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and the glass reactor was stirred to saturate the toluene solution with ethylene, the polymerization temperature was adjusted to 90 ℃ and 2mL of a toluene solution containing 1.5mg of catalyst C was added, the pressure of ethylene was adjusted and maintained at one atmosphere, and the polymerization was carried out for 5 minutes. After the polymerization was completed, the obtained reaction solution was poured into a 10% hydrochloric acid aqueous solution, followed by liquid separation after sufficient stirring, and the organic layer was washed twice with water; and (3) fully stirring the obtained organic layer with acetone, settling, filtering, adding a proper amount of acetone, refluxing for 2 hours, finally filtering the polymer, washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white cyclic olefin copolymer material.

The cycloolefin copolymer obtained in this example had a mass of 0.62g and the polymerization activity of the catalyst was 3.7X 10 ⁶ g mol ^-1 h ^-1 . The cycloolefin copolymer material obtained in this example was determined by high-temperature gel chromatography to have a relative number-average molecular weight of 44kg/mol (weight-average molecular weight of 70.4 kg/mol) and a molecular weight distribution index of 1.6. The insertion rate of the cycloolefin monomer is 37 percent by detecting the obtained cycloolefin copolymer by adopting a high-temperature nuclear magnetic carbon spectrum. Using differential scanningThe glass transition temperature of the cycloolefin copolymer obtained was measured by a thermal method (DSC), and it was found that the glass transition temperature of the cycloolefin copolymer material prepared in this example was 145.7 ℃. The cyclic olefin copolymer prepared in this example has a visible light transmittance of more than 90%.

Example 7

Preparing a catalyst:

the only difference from example 1 is that step (1 c) is not required, and step (1D) is performed directly using the cyclopentadienyl fluorene ligand precursor obtained in step (1 b) as a precursor of catalyst D.

Preparation of cycloolefin copolymer: a glass reactor containing 2.5g of cycloolefin monomer, 2.5mL of MAO (1.5 mol/L in toluene) and 45mL of toluene was placed in an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and the glass reactor was stirred to saturate the toluene solution in the glass reactor with ethylene, the polymerization temperature was adjusted to 90 ℃ C, 1.9mg of catalyst D in 2mL of toluene was added, the pressure of ethylene was adjusted and maintained at one atmosphere, and polymerization was carried out for 5 minutes. After the polymerization is completed, pouring the obtained reaction solution into a 10% hydrochloric acid aqueous solution, fully stirring, separating the solution, and washing the organic layer twice with water; and (3) fully stirring the obtained organic layer with acetone for settling, filtering, adding an appropriate amount of acetone for refluxing for 2 hours, finally filtering the polymer, washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white COC material.

The mass of the cycloolefin copolymer obtained in this example was 1.3g, and the polymerization activity of the catalyst was 7.8X 10 ⁶ g mol ^-1 h ^-1 . The cycloolefin copolymer material obtained in this example was determined by high-temperature gel chromatography to have a relative number-average molecular weight of 11.3kg/mol (weight-average molecular weight of 21.5 kg/mol) and a molecular weight distribution index of 1.9. Detecting the obtained cycloolefin copolymer by adopting high-temperature nuclear magnetic carbon spectrum to obtain the cycloolefinThe insertion rate of the hydrocarbon monomer was 35%. The glass transition temperature of the cycloolefin copolymer obtained was measured by Differential Scanning Calorimetry (DSC), and the result showed that the glass transition temperature of the cycloolefin copolymer material prepared in this example was 142 ℃. The cyclic olefin copolymer prepared in this example has a visible light transmittance of more than 90%.

Comparative example 1

The existing catalyst I (isopropylidene bridged cyclopentadienyl fluorene zirconium dichloride) is adopted for preparing the cycloolefin copolymer.

Preparation of cycloolefin copolymer: a glass reactor containing 4.5g of cycloolefin monomer, 3.4mL of MAO (1.5 mol/L in toluene) and 45mL of toluene was placed in an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and the glass reactor was stirred to saturate the toluene solution with ethylene, the polymerization temperature was adjusted to 50 ℃ and 2mL of a toluene solution containing 0.9mg of catalyst I was added under ethylene introduction, the pressure of ethylene was adjusted and maintained at one atmosphere, and polymerization was carried out for 5 minutes. After the polymerization is completed, pouring the obtained reaction solution into a 10% hydrochloric acid aqueous solution, fully stirring, separating the solution, and washing the organic layer twice with water; and (3) fully stirring the obtained organic layer with acetone for settling, filtering, adding an appropriate amount of acetone for refluxing for two hours, finally filtering the polymer and washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white cyclic olefin copolymer.

The cycloolefin copolymer prepared in this comparative example had a mass of 1.78g and the polymerization activity of the catalyst was 1.1X 10 ⁷ g mol ^-1 h ^-1 . The cycloolefin copolymer was measured by the same method as in the above example to have a number average molecular weight of 124kg/mol (weight average molecular weight of 248 kg/mol) and a molecular weight distribution index of 2.0. The insertion rate of the cycloolefin monomer was 33%. The glass transition temperature of the cycloolefin copolymer was 136.98 ℃.

Comparative example 2

Preparation of cycloolefin copolymer: a glass reactor containing 4.5g of cycloolefin monomer, 1.7mL of MAO (1.5M in toluene) and 45mL of toluene was placed in an ethylene line, the ethylene line was replaced three times with nitrogen, ethylene gas was introduced and the glass reactor was stirred to saturate the toluene solution with ethylene, the polymerization temperature was adjusted to 90 ℃ and 2mL of a toluene solution of 0.9mg of catalyst I was added under ethylene introduction, the pressure of ethylene was adjusted and maintained at one atmosphere, and polymerization was carried out for 5 minutes. After the polymerization is completed, pouring the obtained reaction solution into a 10% hydrochloric acid aqueous solution, fully stirring, separating the solution, and washing the organic layer twice with water; and (3) fully stirring the obtained organic layer with acetone for settling, filtering, adding an appropriate amount of acetone for refluxing for two hours, finally filtering the polymer and washing with acetone for three times, placing the product in a vacuum drying oven, and drying at 130 ℃ for 18 hours to obtain the white cyclic olefin copolymer.

The cycloolefin copolymer prepared in this comparative example had a mass of 1.15g and the polymerization activity of the catalyst was 0.7X 10 ⁷ g mol ^-1 h ^-1 . The number average molecular weight of the cycloolefin copolymer measured in the same manner as in the above example was 117kg/mol (weight average molecular weight: 199 kg/mol), and the molecular weight distribution index was 1.7. The insertion rate of the cycloolefin monomer was 35%. The glass transition temperature of the cycloolefin copolymer was 141.24 ℃.

As can be seen from comparative examples 1 and 2, when the catalyst I of comparative example 1 is used for preparing the cycloolefin copolymer, the prepared cycloolefin copolymer has a weight average molecular weight which is much larger than 150kg/mol (i.e. 15 ten thousand) and a larger molecular weight under different cocatalyst use amounts and polymerization reaction temperatures. Examples 1-7 can obtain a cycloolefin copolymer having a smaller molecular weight with a weight average molecular weight of less than 15 ten thousand by using the catalysts provided in the examples of the present application, mainly because the silicon-containing group on the cyclopentadienyl or fluorenyl group of the main catalyst can compete with the coordination between olefin/metal center by generating weak coordination with the empty orbit of the metal center, thereby promoting chain transfer and reducing the molecular weight of the polymer; meanwhile, through the competition effect, the difficulty of coordination of olefin and a metal center is increased, and the insertion rate of a cycloolefin monomer is improved, so that the adjustment of the glass transition temperature of the cycloolefin copolymer is facilitated.

Claims

1. A catalyst for preparing a cycloolefin copolymer, characterized in that the catalyst comprises a main catalyst having a structural formula shown by the formula (1-a):

in the formula (1-a), D is a bridging group, and Q is a metal center;

R ₅ 、R ₆ 、R ₇ 、R ₈ independently comprise a hydrogen atom, a hydrocarbyl group, or a silicon-containing substituent bonded through a silicon atom to the carbon atom at the corresponding substitution position;

R ₉ 、R ₁₃ 、R ₁₄ 、R ₁₈ independently comprise a hydrogen atom, a hydrocarbyl group or a hydrocarbyloxy group.

2. The catalyst of claim 1, wherein R is ₆ 、R ₇ At least one of which is a silicon-containing substituent, and/or said R _a 、R _b At least one of which is a silicon-containing group.

3. The catalyst of claim 1 or 2, wherein R is ₅ 、R ₆ 、R ₇ 、R ₈ The number of carbon atoms of the medium hydrocarbon group and the silicon-containing substituent is less than or equal to 6.

4. A catalyst according to any one of claims 1 to 3, characterized in that the metal centre Q is represented by-M ¹ (R ₁ R ₂ ) -, said M ¹ Represents scandium, titanium, vanadium, zirconium, hafnium, niobium or tantalum, said R ₁ And R ₂ Independently include a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an alkenyl group, an aryl group, an aryloxy group, an aralkyl group, an alkaryl group or an aralkenyl group.

5. A catalyst according to any one of claims 1 to 4, characterised in that the bridging group D is represented by-X (R) ₃ R ₄ ) -, X represents carbon or silicon, R ₃ And R ₄ Independently comprise a hydrogen atom or a hydrocarbyl group.

6. The catalyst of any one of claims 1-5, wherein R is _a Is represented by-M ² (R ₁₀ R ₁₁ R ₁₂ )，M ² Independently represent carbon, silicon, germanium or tin, R ₁₀ 、R ₁₁ 、R ₁₂ Independently include alkyl, alkoxy, alkenyl, aryl, aryloxy, aralkyl, alkaryl, or aralkenyl.

7. The catalyst of any one of claims 1-6, wherein R is _b Is represented by-M ³ (R ₁₅ R ₁₆ R ₁₇ )，M ³ Independently represent carbon, silicon, germanium or tin, R ₁₅ 、R ₁₆ 、R ₁₇ Independently include alkyl, alkoxy, alkenyl, aryl, aryloxy, aralkyl, alkaryl, or aralkenyl.

8. The catalyst of claim 7, wherein R is ₁₀ 、R ₁₁ 、R ₁₂ 、R ₁₅ 、R ₁₆ 、R ₁₇ Has a carbon number of 10 or less.

9. The catalyst of any one of claims 1 to 8, further comprising a cocatalyst comprising one or more of methylaluminoxane, modified methylaluminoxane, or an organoboron compound.

10. The catalyst of claim 9, wherein the organoboron compound comprises one or more of tris (pentafluorophenyl) boron, triphenylcarbenium tetrakis (pentafluorophenyl) borate, and N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate.

11. The catalyst according to claim 9 or 10, wherein the molar ratio of the main catalyst to the cocatalyst is 1: (10-10000).

12. Catalyst according to any one of claims 1 to 11, characterized in that it has a catalytic activity higher than 10 ⁶ g·mol ^-1 ·h ^-1 。

13. A method for preparing a cycloolefin copolymer, comprising:

copolymerizing a cycloolefin monomer with ethylene or an α -olefin in the presence of the catalyst for cycloolefin copolymer production according to any one of claims 1 to 12 to obtain a cycloolefin copolymer.

14. The preparation method according to claim 13, wherein the copolymerization reaction system comprises an inert solvent, and the inert solvent comprises one or more of linear alkane compounds, cyclic hydrocarbon compounds and aromatic hydrocarbon compounds.

15. The preparation method according to claim 13 or 14, wherein the amount of the procatalyst used in the copolymerization reaction system is 0.001mmol/L to 10mmol/L.

16. The production method according to any one of claims 13 to 15, wherein the cycloolefin monomer is used in an amount of 0.01mol/L to 10mol/L in the reaction system of the copolymerization.

17. The preparation method according to any one of claims 13 to 16, wherein the molar ratio of the cyclic olefin monomer to the procatalyst in the reaction system for copolymerization is 500 to 500000.

18. The method according to any one of claims 13 to 17, wherein the temperature of the copolymerization reaction is 50 ℃ to 120 ℃; the time of the copolymerization reaction is 2min-10min.

19. The method according to any one of claims 13 to 18, wherein the cycloolefin monomer has a structural formula represented by the formula (2):

z is a positive integer.

20. The production method according to any one of claims 13 to 19, wherein a molecular weight modifier is not contained in the copolymerization reaction system.

21. A cycloolefin copolymer obtained by the production method according to any one of claims 13 to 20, characterized in that the cycloolefin copolymer has a structural formula represented by the formula (3):

in the formula (3), R ₁₉ Is hydrocarbyl or hydrocarbyl silyl; r ₂₀ And R ₂₁ Each independently comprises a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a hydroxyl group, an ester group, a carbonate group, a cyano group, an amino group, a thiol group, an atom or an atomic group which may substitute for the above group;

22. The cyclic olefin copolymer according to claim 21, wherein the weight average molecular weight of the cyclic olefin copolymer is in the range of 5000 to 150000; the molecular weight distribution index is in the range of 1.5 to 3.0.

23. The cyclic olefin copolymer according to claim 21 or 22, wherein the insertion rate of the cyclic olefin monomer of the cyclic olefin copolymer is in the range of 20-60%; the glass transition temperature of the cycloolefin copolymer is in the range from 110 ℃ to 180 ℃.

24. A cycloolefin copolymer according to one of the claims 21 to 23, characterized in that the visible light transmission of the shaped body of the cycloolefin copolymer is greater than 90%.

25. A composition comprising a cycloolefin copolymer according to any of claims 21 to 24 or comprising a cycloolefin copolymer prepared by the process according to any of claims 13 to 20.

26. The composition of claim 25, further comprising an additive comprising one or more of a filler, a dye, an antioxidant, a light stabilizer, an ultraviolet absorber, a plasticizer, a flame retardant, an antistatic agent, and a mold release agent.

27. An optical article comprising a cycloolefin copolymer according to one of claims 21 to 24 or comprising a cycloolefin copolymer prepared by the process according to one of claims 13 to 20.

28. The optical article of claim 27, wherein the optical article comprises an optical lens, an optical film, an optical disc, a light guide plate, or a display panel.

29. An electronic device comprising an electronic device body and a camera module mounted on the electronic device body, wherein the camera module comprises a lens made of the cyclic olefin copolymer as claimed in any one of claims 21 to 24, or the composition as claimed in claim 25 or 26.

30. A device comprising the optical article of claim 27 or 28.