CN113773786B - Polyurethane blending composition - Google Patents

Polyurethane blending composition Download PDF

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Publication number
CN113773786B
CN113773786B CN202010521343.8A CN202010521343A CN113773786B CN 113773786 B CN113773786 B CN 113773786B CN 202010521343 A CN202010521343 A CN 202010521343A CN 113773786 B CN113773786 B CN 113773786B
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polyurethane
component
blend composition
dimethylacrylamide
methyl methacrylate
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CN113773786A (en
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夏剑辉
何川
何国恒
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South China University of Technology SCUT
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    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J175/00—Adhesives based on polyureas or polyurethanes; Adhesives based on derivatives of such polymers
    • C09J175/04—Polyurethanes
    • C09J175/14—Polyurethanes having carbon-to-carbon unsaturated bonds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2201/00—Properties
    • C08L2201/08—Stabilised against heat, light or radiation or oxydation

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Macromonomer-Based Addition Polymer (AREA)
  • Adhesives Or Adhesive Processes (AREA)

Abstract

The invention discloses a polyurethane blend composition and a preparation method thereof. The polyurethane blend composition is prepared from raw materials containing a component A and a component B, wherein the component A is polyurethane containing polycarbonate diol; the component B is an acrylate copolymer containing methyl methacrylate and N, N-dimethylacrylamide. The polyurethane blend composition prepared by the invention has good compatibility and good high-temperature resistance.

Description

Polyurethane blending composition
Technical Field
The invention belongs to the field of adhesive compositions, and particularly relates to a polyurethane blending composition.
Background
The polyurethane is widely applied to various adhesion fields due to the unique molecular structure, and has good flexibility, low-temperature performance and excellent buffering and damping functions. However, at higher temperatures (e.g., =80 ℃) the hydrogen bonds between the polyurethane molecules are significantly reduced, resulting in a significant decrease in the mechanical strength of the polyurethane material.
The blending modification method is one of effective methods for improving the high-temperature resistance of polyurethane. Chinese patent No. CN110205081A discloses a two-component adhesive containing modified polyurethane acrylate resin, wherein a high-temperature-resistant filler is added into the system, so that the high-temperature resistance and the environment measurement performance of the adhesive layer can be improved; U.S. Pat. No. 5,8978,898,897,897 discloses a method for preparing a UV-curable pressure-sensitive adhesive with good heat and moisture resistance, which is prepared by blending a polyacrylate (such as a copolymer of isooctyl acrylate and acrylic acid), a monoacrylate-functionalized oligomer, and a PUA oligomer (and a photoinitiator as components), and the cured adhesive film can form a semi-interpenetrating network, has high peel strength (> 40N/dm), and has good heat and moisture resistance.
Besides, a graft modification method can be used, chinese patent No. CN106947053A reports a preparation method of epoxy resin modified polyurethane acrylate adhesive, the method enables polyurethane, acrylate and epoxy resin to react through grafting and free radical polymerization, and the prepared modified polyurethane acrylate adhesive is excellent in heat resistance and bonding performance.
Polyurethanes also have found increased use in optical displays due to their unique flexibility, low temperature and shock absorption capabilities. For materials for optical displays, high light transmission (average transmission in the visible range of 400nm to 800nm > 90%) is often an important condition that must be met. Therefore, the compatibility of the blending system needs to be considered when the blending modification method is used for improving the mechanical properties of polyurethane, because an incompatible system often causes large phase separation, which causes the light transmittance of the blend to be remarkably reduced, and the haze of the blend is increased, so that the blend is not suitable for the application requiring high light transmittance.
There are few reports on transparent polyurethane blends. U.S. patent No. US9790405B2 discloses a uv-curable polyurethane blend for optical displays. The system comprises a mixture of polyurethane consisting of polycarbonate diol and polyphenolic oxygen resin, is a solid glue film when in use, is used for assembling a display module, and is subjected to ultraviolet curing molding after being assembled.
In order to make the high flexibility, low temperature properties, and excellent shock-absorbing function of polyurethane play more roles in an increasing number of optical display devices, it is necessary to research more high-performance polyurethane blends.
Disclosure of Invention
One common problem with polymer blending is adjusting the compatibility between different materials. Incompatible systems can cause phase separation of large size, resulting in a decrease in light transmittance and an increase in haze of the blend composition. Aiming at the problem of low light transmittance of a polyurethane material prepared by a blending method in the prior art, the invention aims to provide a polyurethane blending composition.
In order to achieve the purpose, the invention adopts the following technical scheme:
a polyurethane blend composition is prepared from raw materials containing a component A and a component B, wherein the component A is polyurethane containing polycarbonate diol; the component B is an acrylate copolymer containing methyl methacrylate and N, N-dimethylacrylamide.
Preferably, the mass ratio of the methyl methacrylate to the N, N-dimethylacrylamide in the component B is 8:2-2:8.
Preferably, the mass fraction of the acrylic ester copolymer of methyl methacrylate and N, N-dimethylacrylamide in the component B in the polyurethane blend composition is x, and x is more than or equal to 10% and less than or equal to 50%.
Preferably, the polyurethane of the polycarbonate diol in the component A is a photo-cured polyurethane acrylate.
Preferably, the one polyurethane blend composition further comprises a photoinitiator to initiate a free radical polymerization reaction.
Preferably, the average light transmittance of the polyurethane blend composition in the range of 400nm to 800nm is greater than 90%.
Preferably, the preparation method of the photocuring polyurethane acrylate comprises the following steps: polycarbonate diol is used as oligomer polyol, aliphatic diisocyanate is used as polyisocyanate, micromolecular diol is used as a chain extender, monohydroxy (methyl) acrylate is used as a terminal capping agent, and the photocuring polyurethane acrylate is synthesized.
Preferably, the specific implementation manner of the preparation method of the photocuring urethane acrylate is as follows: adding an organic solvent into polycarbonate diol, then adding aliphatic diisocyanate, controlling the temperature of the system to be not more than 75-85 ℃, dropwise adding a catalyst, and after the catalyst is added and the temperature does not rise any more, raising the temperature to 79-81 ℃; titrating the content of the residual isocyanate NCO in the reaction, adding micromolecular dihydric alcohol when the titration result tends to be stable, adding an organic solvent when the viscosity of the system is increased, measuring the content of the residual isocyanate NCO in the reaction, introducing dry air after the result is stable, then adding a polymerization inhibitor and monohydroxy (methyl) acrylate, tracking the reaction by using a Fourier infrared spectrometer, stopping the reaction after an infrared characteristic peak of-NCO disappears, and storing the product in a dark place.
Preferably, the aliphatic diisocyanate: polycarbonate diol: small molecule dihydric alcohol: the molar weight ratio of the monohydroxy (meth) acrylate is 2: 0.8-1.8: 0.1 to 1:0.2 to 0.8;
the mass of the catalyst accounts for 0.05 to 0.1wt percent of the polycarbonate diol;
the mass of the polymerization inhibitor accounts for 0.05 to 0.1 weight percent of the total mass of all synthetic monomers, and the monomers are aliphatic diisocyanate, polycarbonate diol, micromolecular diol and monohydroxy (methyl) acrylate;
the aliphatic diisocyanate is one or more than two of hexamethylene diisocyanate, 4,4' -dicyclohexylmethane diisocyanate, isophorone diisocyanate, trimethyl hexamethylene diisocyanate, cyclohexane dimethylene diisocyanate, m-phenylene diisocyanate and tetramethyl xylene diisocyanate;
the catalyst is one or two of dibutyltin dilaurate and stannous octoate;
the small molecular diol is one or two of methyl propylene glycol, neopentyl glycol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, hexanediol and 1,4-cyclohexanedimethanol;
the two organic solvents are one or two of acetone, methyl ethyl ketone and ethyl acetate;
the polymerization inhibitor is one or two of 2,6-di-tert-butyl-p-cresol and 4-methoxyphenol;
the monohydroxy (methyl) acrylate is one or two of 2-hydroxyethyl acrylate, hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate and hydroxypropyl methacrylate.
Preferably, the preparation method of the acrylic ester copolymer of methyl methacrylate and N, N-dimethylacrylamide in the component B comprises the following steps: methyl methacrylate and N, N-dimethylacrylamide are taken as polymerization monomers, a chain transfer agent and a chain initiator are added, an organic solvent is added finally, after nitrogen is introduced, the temperature is raised to 60-80 ℃, the reaction is carried out for 18-24 hours, the organic solvent is added finally, the system is diluted, and the product is stored.
Preferably, the mass of the chain transfer agent accounts for 0.1-2.0 wt% of the total mass of the methyl methacrylate and the N, N-dimethylacrylamide;
the addition amount of the chain initiator accounts for 0.1 to 1.0 weight percent of the total amount of the methyl methacrylate and the N, N-dimethylacrylamide;
the chain initiator is one or more than two of azodiisovaleronitrile and azodiisoheptanonitrile;
the chain transfer agent is one or more than two of dodecyl mercaptan, isooctyl thioglycolate, isooctyl 3-mercaptopropionate, 2-mercaptoethanol and 3-mercaptopropionic acid;
the organic solvent is one or two of acetone, methyl ethyl ketone and ethyl acetate.
The mechanism of the invention is as follows:
when the polyacrylate comprises methyl methacrylate and N, N-dimethylacrylamide, the polyacrylate can form a high-light-transmittance blending system with the polycarbonate type polyurethane acrylate. Meanwhile, due to good compatibility, the obtained blending composition can improve the mechanical strength (such as the adhesive force to a substrate) of the polyurethane acrylate material.
Compared with the prior art, the invention has the following advantages and beneficial effects:
the polyurethane blending composition prepared by the invention has good compatibility (represented by high light transmittance of the blend in a visible light range), and meanwhile, the high temperature resistance is good, the high-temperature (70 ℃) stripping force is up to 5.6 (N/25 mm), and the high-temperature (70 ℃) permanent adhesion is more than 10000min.
Detailed Description
The present invention is further illustrated by the following specific examples, which are not intended to limit the scope of the invention. Unless otherwise specified, the following reagents, methods and apparatus are all reagents, methods and apparatus commonly used in the synthesis and processing arts.
Unless otherwise specified, the reagent materials used in the present invention are commercially available, in which the polycarbonate diol has a molecular weight of 1000.
Example 1
A preparation method of a polyurethane blend composition comprises the following preparation steps:
(1) 50.00 g of polycarbonate diol was poured into a 500 ml four-port reaction flask connected with a mechanical stirrer, a condenser tube, a sample inlet and a temperature probeVacuum dewatering at 110 deg.c for 2 hr, cooling to 60 deg.c, introducing nitrogen for ten minutes, adding Methyl Ethyl Ketone (MEK) 30.66 g, hexamethylene Diisocyanate (HDI) 8.41 g and dicyclohexylmethane diisocyanate (HMDI) 13.12 g 4,4' -dicyclohexyl, and slowly dropping dibutyltin dilaurate (DBTDL) 0.025 g to the system at 80 deg.c or below. After the catalyst was added dropwise and the temperature did not rise, the temperature was raised to 80 ℃. The residual isocyanate NCO content of the reaction was titrated by the "di-n-butylamine method". When the titration result is stable, 3.60 g of 1,4-Butanediol (BD) is slowly added, and when the system viscosity is increased, 40.00 g of MEK is added. The reaction was followed by the "di-n-butylamine method" in the same manner, after the results were stabilized, air was blown in for 5 minutes, then 0.038 g 2,6-di-tert-butyl-p-cresol (BHT) and 1.18 g 2-hydroxyethyl acrylate (HEA) were added and the reaction was followed by a Fourier Infrared spectrometer until the characteristic peak of-NCO in the infrared (2270 cm) -1 -2280cm -1 ) Stopping the reaction after the reaction disappears, pouring the product into a reagent bottle for dark storage, and preparing the polyurethane acrylate;
(2) 5 g of Methyl Methacrylate (MMA), 5 g of N, N-dimethylacrylamide (NNDMA) as polymerization monomers, 0.05 g of 2-mercaptoethanol as chain transfer agent, 0.0352 g of Azobisisovaleronitrile (AMBN) as chain initiator were added in portions to a 500 ml flask, and 5.93 g of MEK was added. After 10 minutes of nitrogen is introduced, the temperature is raised to 65 ℃, the reaction is carried out for 24 hours, finally 9.07 g of MEK is added, after the system is diluted, the product is poured into a reagent bottle for storage, and the polyacrylate is prepared;
(3) Uniformly mixing the polyurethane acrylate obtained in the step (1) and the polyacrylate obtained in the step (2) according to a mass ratio of 9:1, adding a photoinitiator Irgacure184 accounting for 1wt% of the total mass of the polyurethane acrylate and the polyacrylate, uniformly mixing, pouring the mixture on a self-made coating machine paved with a polyethylene terephthalate (PET) film or a PET release film (the thickness of which is 50 micrometers) coated with silicon resin, adjusting the distance between a scraper and a bottom plate, slowly pulling the PET film at a constant speed to enable the solution to pass through the scraper to form a thin film with uniform thickness, drying the thin film in an air-blowing drying oven at 80 ℃ for 10 minutes, and covering a layer of release film (the thickness of which is 50 micrometers) on the surface of an adhesive film to obtain the polyurethane blending composition with the adhesive film thickness of 25 micrometers.
Example 2
A preparation method of a polyurethane blend composition comprises the following preparation steps:
(1) The same as example 1;
(2) The same as example 1;
(3) The same procedure as in example 1 was repeated except that the urethane acrylate obtained in step (1) and the polyacrylate obtained in step (2) were mixed and mixed uniformly in a mass ratio of 8:2.
Comparative example 1
A preparation method of urethane acrylate comprises the following preparation steps:
(1) The same as example 1;
(2) Adding Irgacure184 accounting for 1wt% of the mass of the polyurethane acrylate prepared in the step (1), uniformly mixing, pouring the mixture on a self-made coating machine paved with a PET film or a PET release film (the thickness of the PET release film is 50 micrometers), adjusting the distance between a scraper and a bottom plate, slowly pulling the PET film at a constant speed to enable the solution to pass through the scraper to form a film with uniform thickness, then placing the film into an air-blowing drying box at 80 ℃ for drying for 10 minutes, and then covering a layer of release film (the thickness of 50 micrometers) on the surface of a glue film to obtain the polyurethane acrylate glue film with the glue film thickness of 25 micrometers.
Comparative example 2
A preparation method of urethane acrylate comprises the following preparation steps:
(1) The same as example 1;
(2) The same procedure as in example 1 was repeated except that 9 g of Methyl Methacrylate (MMA) and 1 g of N, N-dimethylacrylamide (NNDMA) were used as monomers to be polymerized;
(3) The same as in example 1.
Comparative example 3
A preparation method of urethane acrylate comprises the following preparation steps:
(1) The same as example 1;
(2) The same procedure as in example 1 was repeated, except that 1 g of Methyl Methacrylate (MMA) and 9 g of N, N-dimethylacrylamide (NNDMA) were used as monomers to be polymerized;
(3) The same as in example 1.
And (4) relevant performance test:
the products of examples 1 to 2 and comparative examples 1 to 3 were tested as follows:
the light transmittance was measured by an ultraviolet-visible spectrophotometer.
The normal temperature peel force, the high temperature (70 ℃) peel force and the high temperature (70 ℃) holding power can be respectively tested by a peel strength tester, a constant temperature and humidity type peel strength tester and an oven type adhesive tape holding power tester. The peel force test is referred to the peel force test specification (executive standard GB 2792-1998), and the hold-up test is referred to the test method for the hold-up of adhesive tapes (executive standard GB/T4851-2014). The test results are shown in table 1.
Table 1 summary of performance tests
Figure BDA0002532243550000061
From table 1 it can be derived: the normal-temperature peeling force and the high-temperature (70 ℃) peeling force of the PUA (polyurethane acrylate) modified by the PA (polyacrylate) are obviously improved, the high-temperature (70 ℃) lasting viscosity performance is still better, but when the PA content is 20%, the normal-temperature peeling force of the system is lower than that when the PA content is 10%, and the high-temperature peeling force is not greatly different, so that when the PA content is 10%, the modification effect on the PUA is better.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such modifications are intended to be included in the scope of the present invention.

Claims (5)

1. A polyurethane blend composition is characterized by being prepared from raw materials containing a component A and a component B, wherein the component A is polyurethane containing polycarbonate diol; the component B is an acrylate copolymer containing methyl methacrylate and N, N-dimethylacrylamide;
the mass ratio of the methyl methacrylate to the N, N-dimethylacrylamide in the component B is 8:2-8, and the mass fraction of the acrylic ester copolymer of the methyl methacrylate and the N, N-dimethylacrylamide in the component B in the polyurethane blending composition is x, wherein x is more than or equal to 10% and less than or equal to 50%.
2. The polyurethane blend composition of claim 1, wherein the mass ratio of methyl methacrylate to N, N-dimethylacrylamide in component B is 1:1.
3. The polyurethane blend composition of claim 1, wherein the polyurethane of the polycarbonate diol in component a is a curable urethane acrylate.
4. A polyurethane blend composition according to any one of claims 1 to 3, wherein said polyurethane blend composition further comprises an initiator for initiating a free radical polymerization reaction.
5. A polyurethane blend composition according to any one of claims 1 to 3, wherein said polyurethane blend composition has an average light transmission >90% in the range of 400nm to 800 nm.
CN202010521343.8A 2020-06-10 2020-06-10 Polyurethane blending composition Expired - Fee Related CN113773786B (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102702450A (en) * 2012-05-22 2012-10-03 电子科技大学中山学院 Preparation method of waterborne polyurethane-acrylate emulsion
CN104812858A (en) * 2012-08-20 2015-07-29 汉高股份有限公司 Liquid optically clear photo-curable adhesive for display application
CN105294019A (en) * 2015-07-31 2016-02-03 华南理工大学 Polyurethane-polyacrylate cement water-proof coating and preparation method thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SG11201605804WA (en) * 2014-01-17 2016-08-30 Nuplex Resins Bv Waterborne coating composition with improved open time

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102702450A (en) * 2012-05-22 2012-10-03 电子科技大学中山学院 Preparation method of waterborne polyurethane-acrylate emulsion
CN104812858A (en) * 2012-08-20 2015-07-29 汉高股份有限公司 Liquid optically clear photo-curable adhesive for display application
CN105294019A (en) * 2015-07-31 2016-02-03 华南理工大学 Polyurethane-polyacrylate cement water-proof coating and preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
含双键丙烯酸酯共聚物乳液的制备及聚氨酯-丙烯酸酯UV双固化体系的研究;夏宇正等;《北京化工大学学报(自然科学版)》;20100120(第01期);第59-63页 *

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