CN112409579A - Polyester and preparation method and application thereof - Google Patents
Polyester and preparation method and application thereof Download PDFInfo
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- CN112409579A CN112409579A CN201910785372.2A CN201910785372A CN112409579A CN 112409579 A CN112409579 A CN 112409579A CN 201910785372 A CN201910785372 A CN 201910785372A CN 112409579 A CN112409579 A CN 112409579A
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- monomer
- polyester
- catalyst
- hydrogenated bisphenol
- cyclohexanedicarboxylate
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
- C08G63/12—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from polycarboxylic acids and polyhydroxy compounds
- C08G63/16—Dicarboxylic acids and dihydroxy compounds
- C08G63/18—Dicarboxylic acids and dihydroxy compounds the acids or hydroxy compounds containing carbocyclic rings
- C08G63/199—Acids or hydroxy compounds containing cycloaliphatic rings
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/78—Preparation processes
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Polyesters Or Polycarbonates (AREA)
Abstract
The invention relates to polyester and a preparation method and application thereof. The polyester has the following structure:
Description
Technical Field
The invention relates to the field of polyester materials, in particular to polyester and a preparation method and application thereof.
Background
In order to meet the requirements of the 5G era, electronic products are miniaturized and lightened, the requirements for high signal transmission speed, low transmission loss and signal integrity are increasingly improved, the dielectric properties of polymer materials are widely concerned, and low-dielectric-constant polymer materials are the key points of research. The high molecular polyester is a general engineering plastic which is widely applied, has excellent mechanical property, heat resistance, wear resistance and stable size, and has wide application prospect in the field of low dielectric engineering plastics.
At present, common polyesters in the market, such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and the like, have dielectric constants of over 2.9 at high frequencies of more than 1GHz, and cannot meet the increasing requirements of polymer materials in the electronic field. Particularly, in an environment of rapid development of 5G technology, in order to realize high-speed and low-delay transmission of information, a higher requirement is put on the dielectric property of polyester in both a signal transmission part of a mobile phone terminal and a sensor material for intelligent driving of a vehicle.
Disclosure of Invention
The present invention aims to overcome the problems in the prior art and provide a polyester, a preparation method and an application thereof. The polyester has low dielectric constant and meets the requirements of the 5G era.
In a first aspect the present invention provides a polyester having the structure:
Preferably, the weight average molecular weight of the polyester is 5000-50000 and the molecular weight distribution index is 1.5-2.5.
Preferably, the polyester has a dielectric constant of 2.6 to 2.7.
The second aspect of the invention provides a method for preparing the polyester, which comprises the steps of carrying out polycondensation reaction on the monomer A and the monomer B to obtain the polyester; the monomer A is 1, 4-cyclohexanedicarboxylic acid, and the monomer B is hydrogenated bisphenol A and/or hydrogenated bisphenol A dicarboxylate; or the monomer A is 1, 4-cyclohexane diformate, and the monomer B is hydrogenated bisphenol A.
Preferably, the 1, 4-cyclohexanedicarboxylate ester comprises one or more of dimethyl 1, 4-cyclohexanedicarboxylate, diethyl 1, 4-cyclohexanedicarboxylate, dipropyl 1, 4-cyclohexanedicarboxylate, dialkyl 1, 4-cyclohexanedicarboxylate and diaryl 1, 4-cyclohexanedicarboxylate; the hydrogenated bisphenol A dicarboxylate comprises hydrogenated bisphenol A dicarboxylate and/or hydrogenated bisphenol A diacetate.
Preferably, the molar ratio of the A monomer to the B monomer is (0.99-1.01): 1.
Preferably, the polycondensation reaction comprises the steps of:
s1, mixing the monomer A and the monomer B, heating the mixture under protective atmosphere until the monomer A and the monomer B are molten, adding a catalyst, stirring the mixture for reaction, continuing heating the mixture for the first time to 190-215 ℃, and stirring the mixture for reaction for 2-4 hours;
s2, vacuumizing for 2-3h, and heating to 220-240 ℃ for the second time in the reaction process;
s3, heating to 245-260 ℃ for the third time, and reacting for 1-2h to obtain the polyester.
Preferably, the system pressure of the step S2 is 500-1000 Pa; the system pressure of the step S3 is lower than 200 Pa.
Preferably, the catalyst is added in a batch, the batch being 1-4 times.
Preferably, the content of the catalyst is 0.04-0.2% of the total mass of the A monomer and the B monomer.
Preferably, the catalyst is one or more of a titanium-based catalyst, a tin-based catalyst, an antimony-based catalyst, a germanium-based catalyst, and a metal acetate catalyst.
The third aspect of the invention is to provide an application of the polyester or the polyester obtained by the preparation method in the fields of electronic products or automobiles.
The polyester provided by the invention contains a large number of cyclohexane structural units, can increase the free volume of polyester molecules and reduce the dielectric constant of the polyester, meets the requirements of the 5G era, and can be well applied to the field of electronic products or automobiles.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Detailed Description
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
The invention provides a polyester having the following structure:
In the present invention, the weight average molecular weight of the polyester is 5000-50000 and the molecular weight distribution index is 1.5-2.5. Preferably, the polyester has a dielectric constant of 2.6 to 2.7 at 2.5GHz, which is lower than that of the currently common polyester.
The invention also provides a preparation method of the polyester, which comprises the steps of carrying out polycondensation reaction on the monomer A and the monomer B to obtain the polyester; the monomer A is 1, 4-cyclohexanedicarboxylic acid, and the monomer B is hydrogenated bisphenol A and/or hydrogenated bisphenol A dicarboxylate; or the monomer A is 1, 4-cyclohexane diformate, and the monomer B is hydrogenated bisphenol A.
In the present invention, the monomer a is 1, 4-cyclohexanedicarboxylic acid and/or 1, 4-cyclohexanedicarboxylate, and the structure of the monomer a is not limited in the present invention, and may be cis-structure and/or trans-structure. Specifically, the 1, 4-cyclohexanedicarboxylic acid (CHDA) may be selected from cis-structure CHDA (e.g., CAS: 619-81-8), trans-structure CHDA (e.g., CAS: 619-82-9), cis-trans isomer mixture CHDA (e.g., CAS: 1076-97-7); the 1, 4-cyclohexanedicarboxylate ester includes but is not limited to one or more of dimethyl 1, 4-cyclohexanedicarboxylate, diethyl 1, 4-cyclohexanedicarboxylate, dipropyl 1, 4-cyclohexanedicarboxylate, dialkyl 1, 4-cyclohexanedicarboxylate and diaryl 1, 4-cyclohexanedicarboxylate, and the structure of the 1, 4-cyclohexanedicarboxylate ester can be cis structure and/or trans structure.
In the invention, the B monomer is hydrogenated bisphenol A and/or hydrogenated bisphenol A dicarboxylate, and the structure of the A monomer is not limited and can be cis structure and/or trans structure; the hydrogenated bisphenol A dicarboxylate comprises hydrogenated bisphenol A dicarboxylate and/or hydrogenated bisphenol A diacetate. Specifically, the hydrogenated bisphenol A is also known as 2, 2-bis- (4-hydroxycyclohexyl) propane.
In the invention, the molar ratio of the monomer A to the monomer B is (0.99-1.01):1, which is beneficial to the synthesis of high molecular weight polyester; too much or too little will result in too low molecular weight of the polyester, which is not favorable for the mechanical properties of the material.
In the present invention, the polycondensation reaction includes the steps of:
s1, mixing the monomer A and the monomer B, heating the mixture under protective atmosphere until the monomer A and the monomer B are molten, adding a catalyst, stirring the mixture for reaction, continuing heating the mixture for the first time to 190-215 ℃, and stirring the mixture for reaction for 2-4 hours;
s2, vacuumizing for 2-3h, and heating to 220-240 ℃ for the second time in the reaction process;
s3, heating to 245-260 ℃ for the third time, and reacting for 1-2h to obtain the polyester.
Specifically, the monomer A and the monomer B in the step S1 are mixed according to the molar ratio of (0.99-1.01):1, added into a reaction vessel, heated under a protective atmosphere (such as nitrogen) until the monomer A and the monomer B are molten, and then added with a catalyst to promote the reaction. Preferably, the catalyst is added in a batch, the batch being 1-4 times. The catalyst is added in batches, so that the loss caused by catalyst volatilization and catalyst carrying-out along with small molecular products can be compensated, and the reaction is favorably carried out and the molecular weight of the products is favorably improved.
In the invention, the content of the catalyst is 0.04-0.2% of the total mass of the monomer A and the monomer B. The catalyst may be a catalyst conventionally used in the art, and for example, may be selected from one or more of a titanium-based catalyst, a tin-based catalyst, an antimony-based catalyst, a germanium-based catalyst, and a metal acetate catalyst. The titanium-based catalyst comprises one or more of tetrabutyl titanate, tetraethyl titanate and tetraisopropyl titanate; the tin-based catalyst includes, but is not limited to, one or more of dibutyltin diacetate, dibutyltin oxide, dibutyltin dilaurate; the antimony catalyst is selected from antimony trioxide, ethylene glycol antimony and the like; the germanium-based catalyst includes, but is not limited to, germanium dioxide; the metal acetate catalyst includes but is not limited to zinc acetate, magnesium acetate, cadmium acetate.
In the invention, the step S2 needs to be performed with vacuum pumping, the temperature is increased to 220-240 ℃ for the second time in the reaction process, because the viscosity of the system is increased after the step S1 is completed, the temperature needs to be increased continuously to reduce the viscosity, and the vacuum degree is gradually increased to discharge the micromolecular by-products, so that the equilibrium moves in the forward direction, and the polymerization degree is increased. It should be noted that, during the vacuum pumping process, the vacuum degree of the system will gradually increase, and the pressure of the system will gradually decrease. Preferably, the system pressure of the step S2 is 500-1000 Pa.
In the invention, in order to further reduce the viscosity of the system, promote the forward reaction, and increase the polymerization degree and the molecular weight, the temperature in the step S3 needs to be raised to 240-260 ℃ for reaction for 1-2h for the third time to obtain the polyester. Preferably, the system pressure of step S3 is lower than 200 Pa.
The invention also provides application of the polyester or the polyester obtained by the preparation method in the fields of electronic products or automobiles. Preferably, the polyester can be applied to a signal transmission part of a mobile phone terminal or a sensor for intelligent driving of a vehicle. The polyester has low dielectric constant and can meet the requirements of the 5G era.
The present invention will be described in detail below by way of examples, but the present invention is not limited to the following examples.
And (3) testing molecular weight: the weight average molecular weight and the molecular weight distribution index of the solution polyester are measured by using SH 1759-2007 gel permeation chromatography.
And (3) dielectric constant test: the resonant cavity method adopts GB/T1409-.
Example 1
(1) Adding 43g (0.25 mol) of 1, 4-cyclohexanedicarboxylic acid (purchased from an avadin reagent, CAS number is 1076-97-7) and 60g (0.25 mol) of hydrogenated bisphenol A (purchased from a Meclin reagent, CAS number is 80-04-6) into a 250ml three-neck flask, heating a reaction system to 180 ℃ under the condition of nitrogen protection, dropwise adding 51.5mg (0.05 wt%) of tetrabutyl titanate after reactants are completely melted, reacting for 2h, dropwise adding 51.5mg (0.05 wt%) of tetrabutyl titanate, mechanically stirring, heating the reaction system to 200 ℃, and reacting for 2 h;
(2) continuously heating to 220 ℃, connecting the system with a vacuum pump when no water is distilled out of the reaction system, gradually increasing the vacuum degree of the system, reducing the pressure of the system, and simultaneously increasing the temperature of the system at the speed of 10 ℃/h for reacting for 2 h;
(3) continuously heating to 250 ℃, wherein the system pressure is 150Pa, and reacting for 1h to obtain the final polyester A1, wherein the structure is as follows:
wherein n is more than 30 and less than 35, the reaction process for obtaining A1 is as follows:
the weight average molecular weight of polyester A1 was 25000, the molecular weight distribution index was 1.9; the dielectric constant was 2.61 at 2.5 GHz.
Example 2
(1) Adding 43g (0.25 mol) of 1, 4-cyclohexanedicarboxylic acid and 60g (0.25 mol) of hydrogenated bisphenol A into a 250ml three-neck flask, heating a reaction system to 180 ℃ under the protection of nitrogen, dropwise adding 103mg (0.1 wt%) of tetrabutyl titanate after reactants are completely molten, reacting for 2h, heating the reaction system to 200 ℃, and reacting for 2 h;
(2) continuously heating to 220 ℃, connecting the system with a vacuum pump when no water is distilled out of the reaction system, gradually increasing the vacuum degree of the system, and simultaneously increasing the temperature of the system at the speed of 10 ℃/h for reacting for 2 h;
(3) continuously heating to 250 ℃, wherein the system pressure is 150Pa, and reacting for 1h to obtain the final polyester A2, wherein the structure is as follows:
wherein n is more than 23 and less than 28.
The weight average molecular weight of polyester A2 was 19000, and the molecular weight distribution index was 2.1; at 2.5GHz, the dielectric constant is 2.66.
Example 3
The procedure was as in example 1, except that the starting material 1, 4-cyclohexanedicarboxylic acid was changed to 1, 4-cyclohexanedicarboxylic acid dimethyl ester (available from the avadin reagent under CAS number 94-60-0). The final polyester A3 was obtained, having the structure:
wherein n is more than 25 and less than 30, the reaction process for obtaining A3 is as follows:
the weight average molecular weight of the polyester A3 was 21600, and the molecular weight distribution index was 1.9; at 2.5GHz, the dielectric constant is 2.64.
Example 4
The procedure was as in example 1, except that the starting hydrogenated bisphenol A was changed to hydrogenated bisphenol A diacetate. The final polyester A4 was obtained, having the structure:
wherein n is more than 20 and less than 25, the reaction process for obtaining A4 is as follows:
the weight average molecular weight of polyester A4 was 15000, the molecular weight distribution index was 2.3; at 2.5GHz, the dielectric constant is 2.68.
Example 5
The preparation was carried out in the same manner as in example 1, except for using 46.5g (0.27 mol) of 1, 4-cyclohexanedicarboxylic acid and 60g (0.25 mol) of hydrogenated bisphenol A. The final polyester A5 was obtained, having the structure:
wherein n is more than 5 and less than 10.
The weight average molecular weight of polyester A5 was 4960, and the molecular weight distribution index was 2.2; the dielectric constant was 2.71 at 2.5 GHz.
Comparative example 1
Polyethylene terephthalate (purchased from Tenglong Special resin, with a commercial code of TL 102) with a weight average molecular weight of 59000 and a molecular weight distribution index of 2.4; the dielectric constant was 3.0 at 2.5 GHz.
Comparative example 2
The procedure was as in example 1, except that the starting hydrogenated bisphenol A was changed to 1, 4-butanediol (available from national reagent under CAS number 110-63-4). The final polyester D2 was obtained, having the structure:
the weight average molecular weight of polyester D2 was 44000, the molecular weight distribution index was 2.5; the dielectric constant was 2.97 at 2.5 GHz.
Since the lower the dielectric constant, the faster the signal transmission speed and the lower the transmission loss, the lower the dielectric constant, the better the performance without affecting other properties of the material. The dielectric constant of the existing low-dielectric polymer is more than 2.9, which can barely meet the requirement of 5G low frequency, but along with the increase of signal frequency, the dielectric constant of 5G high frequency is generally lower than 2.7. As can be seen from the results of the examples and the comparative examples, the polyester provided by the invention has low dielectric constant at 2.5GHz, and is suitable for the requirement of 5G high frequency.
The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.
In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (12)
1. A polyester, characterized in that the polyester has the following structure:
2. The polyester as claimed in claim 1, wherein the polyester has a weight average molecular weight of 5000-50000 and a molecular weight distribution index of 1.5-2.5.
3. The polyester according to claim 1, wherein the polyester has a dielectric constant of 2.6 to 2.7.
4. A process for the preparation of a polyester, which comprises subjecting a monomer a and a monomer B to a polycondensation reaction to obtain a polyester according to any one of claims 1 to 3; the monomer A is 1, 4-cyclohexanedicarboxylic acid, and the monomer B is hydrogenated bisphenol A and/or hydrogenated bisphenol A dicarboxylate; or the monomer A is 1, 4-cyclohexane diformate, and the monomer B is hydrogenated bisphenol A.
5. The production method according to claim 4, wherein the 1, 4-cyclohexanedicarboxylic acid ester comprises one or more of dimethyl 1, 4-cyclohexanedicarboxylate, diethyl 1, 4-cyclohexanedicarboxylate, dipropyl 1, 4-cyclohexanedicarboxylate, dialkyl 1, 4-cyclohexanedicarboxylate and diaryl 1, 4-cyclohexanedicarboxylate; the hydrogenated bisphenol A dicarboxylate comprises hydrogenated bisphenol A dicarboxylate and/or hydrogenated bisphenol A diacetate.
6. The method according to claim 4, wherein the molar ratio of the A monomer to the B monomer is (0.99-1.01): 1.
7. The method according to claim 4, wherein the polycondensation reaction comprises the steps of:
s1, mixing the monomer A and the monomer B, heating the mixture under protective atmosphere until the monomer A and the monomer B are molten, adding a catalyst, stirring the mixture for reaction, continuing heating the mixture for the first time to 190-215 ℃, and stirring the mixture for reaction for 2-4 hours;
s2, vacuumizing for 2-3h, and heating to 220-240 ℃ for the second time in the reaction process;
s3, heating to 245-260 ℃ for the third time, and reacting for 1-2h to obtain the polyester.
8. The method as claimed in claim 7, wherein the system pressure of step S2 is 500-1000 Pa; the system pressure of the step S3 is lower than 200 Pa.
9. The method according to claim 7, wherein the catalyst is added in a batch, and the batch is 1 to 4 times.
10. The preparation method according to claim 7, wherein the content of the catalyst is 0.04-0.2% of the total mass of the A monomer and the B monomer.
11. The method according to claim 7, wherein the catalyst is one or more of a titanium-based catalyst, a tin-based catalyst, an antimony-based catalyst, a germanium-based catalyst, and a metal acetate catalyst.
12. Use of a polyester according to any of claims 1 to 3 or obtained by a process according to any of claims 4 to 11 in the field of electronics or automotive applications.
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| CN201910785372.2A CN112409579A (en) | 2019-08-23 | 2019-08-23 | Polyester and preparation method and application thereof |
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| CN201910785372.2A CN112409579A (en) | 2019-08-23 | 2019-08-23 | Polyester and preparation method and application thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115109240A (en) * | 2021-03-23 | 2022-09-27 | 比亚迪股份有限公司 | Copolyester and preparation method and application thereof |
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|---|---|---|---|---|
| US5097006A (en) * | 1990-11-21 | 1992-03-17 | U C B S.A. | Weatherable powder coating compositions |
| US5439988A (en) * | 1992-03-16 | 1995-08-08 | U C B S.A. | Carboxyl-terminated polyesters for the preparation of powder coating compositions |
| JPH10130380A (en) * | 1996-10-28 | 1998-05-19 | Tomoegawa Paper Co Ltd | Polyester resin and its production |
| JP2003048966A (en) * | 2001-08-09 | 2003-02-21 | New Japan Chem Co Ltd | Method for producing alicyclic polyester using saturated cycloaliphatic secondary alcohol as raw material |
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2019
- 2019-08-23 CN CN201910785372.2A patent/CN112409579A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5097006A (en) * | 1990-11-21 | 1992-03-17 | U C B S.A. | Weatherable powder coating compositions |
| US5439988A (en) * | 1992-03-16 | 1995-08-08 | U C B S.A. | Carboxyl-terminated polyesters for the preparation of powder coating compositions |
| JPH10130380A (en) * | 1996-10-28 | 1998-05-19 | Tomoegawa Paper Co Ltd | Polyester resin and its production |
| JP2003048966A (en) * | 2001-08-09 | 2003-02-21 | New Japan Chem Co Ltd | Method for producing alicyclic polyester using saturated cycloaliphatic secondary alcohol as raw material |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115109240A (en) * | 2021-03-23 | 2022-09-27 | 比亚迪股份有限公司 | Copolyester and preparation method and application thereof |
| CN115109240B (en) * | 2021-03-23 | 2024-01-30 | 比亚迪股份有限公司 | Copolyester and preparation method and application thereof |
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