A kind of silicone modified UV curable peelable adhesive and its preparation method and application

Abstract

The present invention belongs to the technical field of polymer materials, and particularly relates to a silicone-modified UV-cured peelable adhesive and its preparation method and application. A peelable adhesive comprises silicone-modified polyurethane acrylate, a monomer, and a photoinitiator; the silicone-modified polyurethane acrylate is obtained by modifying polyurethane acrylate with butanone oxime and 3-aminopropyltriethoxysilane; and the monomer comprises an acrylate monomer. The present invention uses butanone oxime as a catalyst and 3-aminopropyltriethoxysilane as an organosilicon modifier to modify polyurethane acrylate to obtain silicone-modified polyurethane acrylate, and then through the joint action of the silicone-modified polyurethane acrylate, the monomer, and the photoinitiator, the peelable adhesive has good temperature resistance, weather resistance, is easy to peel, and has a fast curing speed.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and particularly relates to an organosilicon-modified UV-cured peelable adhesive and a preparation method and application thereof. Background Art

[0002] Peelable adhesive is mainly used for protective films of indium tin oxide glass (ITO), solder mask protective films of PCB boards, etc., such as temporary protective films of various electronic touch screens, liquid crystal panels, and temporary protective films of circuit boards. When in use, the peelable adhesive is applied to the material by spot coating or spraying. After curing into a film, it can prevent the material from being scratched in the subsequent production process, and can also play a role in moisture-proof and insulation. Before the next process, it can be peeled off by a simple method, and the requirement is that it can be peeled off cleanly in one go to avoid the problem of unclean peelable adhesive peeling, colloid residue on the surface of the material, and contamination of the material.

[0003] At present, peelable adhesives generally include thermosetting, solvent evaporation, room temperature curing, and UV curing. The room temperature curing peelable adhesive has a long curing time and low production efficiency, and cannot meet the needs of large-scale production; the traditional UV curing peelable adhesive has poor temperature resistance and weather resistance. After high and low temperature impact and high temperature and high humidity treatment, it is easy to harden and yellow, resulting in poor flexibility, which makes it difficult to peel off from the surface of the material. In addition, the traditional UV curing peelable adhesive is cured by UV mercury lamps. Mercury lamps contain mercury, which pollutes the environment and is harmful to the human body. It also has high energy consumption and a short lifespan. In addition, with the development of society and the improvement of living standards, people's performance requirements for electronic products have become higher and higher. Traditional UV curing peelable adhesives can no longer meet the performance requirements of electronic products.

[0004] Therefore, there is an urgent need to provide a silicone-modified UV-curable peelable adhesive, which has good temperature resistance, weather resistance, is easy to peel, can be cured by UV LED lamp, has a fast curing speed, is safe and environmentally friendly. Summary of the invention

[0005] The present invention aims to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions. The present invention provides a silicone-modified UV-curable peelable adhesive, which has good temperature resistance, weather resistance, and is easy to peel, and can be cured by UV LED lamp, has a fast curing speed, and is safe and environmentally friendly.

[0006] The inventive concept of the present invention is as follows: the present invention uses butanone oxime as a catalyst and 3-aminopropyltriethoxysilane as an organosilicon modifier to modify polyurethane acrylate to obtain organosilicon-modified polyurethane acrylate, the structure of the organosilicon modifier contains both "organic groups" and "inorganic structures", and has excellent heat resistance and weather resistance. The heat resistance and weather resistance of polyurethane acrylate can be greatly improved after being modified with organosilicon; then, through the joint action of organosilicon-modified polyurethane acrylate, monomers and photoinitiators, the prepared peelable adhesive has good heat resistance and weather resistance, is easy to peel and has a fast curing speed.

[0007] Therefore, a first aspect of the present invention provides a silicone-modified UV-curable peelable adhesive.

[0008] Specifically, an organosilicon-modified UV-curable peelable adhesive includes organosilicon-modified polyurethane acrylate, monomer, and photoinitiator;

[0009] The organosilicon-modified polyurethane acrylate is obtained by modifying polyurethane acrylate with butanone oxime and 3-aminopropyltriethoxysilane;

[0010] The monomers include acrylic ester monomers.

[0011] Preferably, at 25° C., the viscosity of the silicone-modified polyurethane acrylate is 2000-6000 mPa·s.

[0012] Further preferably, at 25° C., the viscosity of the silicone-modified polyurethane acrylate is 4000-5000 mPa·s.

[0013] Preferably, the strippable adhesive further comprises at least one of a leveling agent, a dispersant and a pigment.

[0014] Preferably, the strippable adhesive comprises, by weight, 27-55 parts of silicone-modified polyurethane acrylate, 18-33 parts of monomer, 1-12 parts of photoinitiator, 0.01-1.2 parts of leveling agent, 0.08-1.2 parts of dispersant, and 0.01-1.2 parts of pigment.

[0015] Further preferably, the strippable adhesive comprises, by weight, 30-50 parts of silicone-modified polyurethane acrylate, 20-30 parts of monomer, 1-10 parts of photoinitiator, 0.01-1 part of leveling agent, 0.1-1 part of dispersant, and 0.01-1 part of pigment.

[0016] Preferably, the monomer is selected from at least one of 2-phenoxyethyl acrylate, tetrahydrofuran acrylate, isobornyl acrylate, dicyclopentadienyl acrylate, 2-dodecyl acrylate, 3.3.5-trimethylcyclohexyl acrylate and 1,6-hexanediol dimethacrylate.

[0017] Preferably, the photoinitiator is selected from at least one of 1-hydroxycyclohexyl phenyl ketone, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 2,4,6-trimethylbenzoylphosphonic acid ethyl ester, and phenylbis(2,4,6-trimethylbenzoyl)oxybenzoylformic acid methyl ester.

[0018] Preferably, the leveling agent is selected from at least one of polydimethylsiloxane, polymethylphenylsiloxane, polyether polyester modified organic siloxane and alkyl modified organic siloxane.

[0019] Preferably, the dispersant is selected from at least one of polycarboxylates, poly(meth)acrylic acid derivatives, maleic anhydride copolymers, alkylbenzene sulfonates, polyoxyethylene alkylphenol ethers, sorbitol alkylates, and sodium hexametaphosphate.

[0020] Preferably, the pigment is selected from at least one of cobalt blue, cobalt chrome blue, iron blue, ultramarine blue and phthalocyanine blue.

[0021] The second aspect of the present invention provides a method for preparing the silicone-modified UV-curable peelable adhesive according to the first aspect of the present invention, comprising the following steps:

[0022] The peelable adhesive is prepared by mixing various raw material components and performing vacuum degassing.

[0023] Preferably, the vacuum degassing process is stirred; the stirring speed is 90-330 r / min, and the stirring time is 27-65 min.

[0024] Further preferably, the stirring speed is 100-300 r / min, and the stirring time is 30-60 min.

[0025] The vacuum degree of the vacuum degassing is -0.09 to -0.1 MPa; further preferably, the vacuum degree of the vacuum degassing is -0.09 to -0.095 MPa.

[0026] Preferably, the method for preparing the silicone-modified UV-curable peelable adhesive comprises the following steps:

[0027] (1) placing organosilicon-modified polyurethane acrylate, monomer, and photoinitiator into a planetary stirrer and stirring to obtain a mixture;

[0028] (2) adding a leveling agent, a dispersant and a pigment to the mixture obtained in step (1), stirring, and then evacuating and degassing the mixture to obtain the peelable adhesive.

[0029] Preferably, in step (1), the stirring speed is 180-450 r / min, and the stirring time is 80-130 min.

[0030] Further preferably, in step (1), the stirring speed is 200-400 r / min, and the stirring time is 90-120 min.

[0031] Preferably, in step (2), the stirring speed is 360-650 r / min, and the stirring time is 55-100 min.

[0032] Further preferably, in step (2), the stirring speed is 400-600 r / min, and the stirring time is 60-90 min.

[0033] Preferably, the process parameters of the vacuum degassing in step (2) are the same as the process parameters of the vacuum degassing described above.

[0034] Preferably, the preparation method of the organosilicon-modified polyurethane acrylate comprises the following steps:

[0035] (1) mixing diisocyanate and a catalyst, and adding polypropylene glycol to prepare a mixed solution;

[0036] (2) adding hydroxypropyl acrylate and a polymerization inhibitor to the mixed solution obtained in step (1) to prepare polyurethane acrylate;

[0037] (3) adding butanone oxime and 3-aminopropyltriethoxysilane to the polyurethane acrylate obtained in step (2), and distilling to obtain the organosilicon-modified polyurethane acrylate.

[0038] Specifically, polypropylene glycol first reacts with diisocyanate to extend the chain, and then reacts with hydroxypropyl acrylate, which can shorten the residence time of hydroxypropyl acrylate in the reaction container, avoid excessive polymerization and even gelation of hydroxypropyl acrylate due to long heating time, and reduce the viscosity of polyurethane acrylate. In addition, the reaction is easy to control and the viscosity is easy to adjust by completing the reaction in steps, ensuring that the peelable adhesive has a suitable viscosity and is easy to peel.

[0039] Specifically, polyurethane acrylate is modified by using butanone oxime as a catalyst and 3-aminopropyltriethoxysilane as an organosilicon modifier, so that the temperature resistance and weather resistance of polyurethane acrylate can be improved; and the modified polyurethane acrylate is non-corrosive to substrates such as ITO, and the catalyst and by-products can be removed by distillation under high temperature and negative pressure conditions. The product has low odor, no small molecule volatiles, and good stability.

[0040] Preferably, the diisocyanate is selected from at least one of 2,4-toluene diisocyanate, isophorone diisocyanate and diphenylmethane diisocyanate.

[0041] Preferably, the catalyst is selected from at least one of dibutyltin dilaurate, stannous isooctanoate, bismuth isooctanoate and zinc isooctanoate.

[0042] Preferably, the polymerization inhibitor is selected from at least one of p-oxymethylphenol and hydroquinone.

[0043] Preferably, in step (1), after the diisocyanate and the catalyst are mixed, they are stirred under heating conditions, the temperature is increased, and then polypropylene glycol is added dropwise and stirred to obtain a mixed solution.

[0044] Preferably, the heating temperature is 45-65°C, and the stirring time is 8-22 min; further preferably, the heating temperature is 50-60°C, and the stirring time is 10-20 min.

[0045] Preferably, the heating temperature is 65-80° C., and the stirring time after adding polypropylene glycol is 2.5-4.5 hours; further preferably, the heating temperature is 70-75° C., and the stirring time after adding polypropylene glycol is 3-4 hours.

[0046] Preferably, in step (2), the mixing is carried out by stirring and heating; the temperature of the stirring and heating is 65-95°C, and the time of the stirring and heating is 2.5-4.5h; further preferably, the temperature of the stirring and heating is 75-85°C, and the time of the stirring and heating is 3-4h.

[0047] Preferably, in step (3), butanone oxime is first added to the polyurethane acrylate obtained in step (2), and then 3-aminopropyltriethoxysilane is added and distilled to obtain the silicone-modified polyurethane acrylate.

[0048] Preferably, in step (3), after butanone oxime is added to the polyurethane acrylate obtained in step (2), the mixture is first stirred at room temperature for 8-22 minutes, then heated to 75-90°C, 3-aminopropyltriethoxysilane is added, stirred for 1.5-3.5 hours, and distilled at 160-200°C to obtain the silicone-modified polyurethane acrylate.

[0049] More preferably, the mixture is stirred at room temperature for 10-20 minutes, then heated to 80-85° C., 3-aminopropyltriethoxysilane is added, stirred for 2-3 hours, and distilled at 170-190° C. to obtain the silicone-modified polyurethane acrylate.

[0050] Preferably, the distillation is carried out by negative pressure distillation; the pressure of the negative pressure distillation is -0.09 to -0.1 MPa; further preferably, the pressure of the negative pressure distillation is -0.09 to -0.095 MPa.

[0051] Preferably, the addition amounts of each raw material component are respectively: 60-88 parts of diisocyanate, 0.02-0.12 parts of catalyst, 18-44 parts of polypropylene glycol, 45-65 parts of hydroxypropyl acrylate, 0.02-0.12 parts of inhibitor, 1.8-4.4 parts of butanone oxime, and 55-88 parts of 3-aminopropyltriethoxysilane.

[0052] Further preferably, the added amounts of each raw material component are, by weight, 65-80 parts of diisocyanate, 0.02-0.1 parts of catalyst, 20-40 parts of polypropylene glycol, 50-60 parts of hydroxypropyl acrylate, 0.02-0.1 parts of inhibitor, 2-4 parts of butanone oxime, and 60-80 parts of 3-aminopropyltriethoxysilane.

[0053] The third aspect of the present invention provides an application of the organosilicon-modified UV-cured peelable adhesive described in the first aspect of the present invention in the field of electronics and electrical appliances.

[0054] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0055] (1) The present invention uses butanone oxime as a catalyst and 3-aminopropyltriethoxysilane as an organosilicon modifier to modify polyurethane acrylate to obtain organosilicon-modified polyurethane acrylate, and then through the joint action of organosilicon-modified polyurethane acrylate, monomer, and photoinitiator, the peelable adhesive has good temperature resistance and weather resistance, is easy to peel, and has a fast curing speed.

[0056] (2) The present invention performs modification of polyurethane acrylate in steps, so that the reaction is easy to control and the viscosity is easy to adjust, thereby ensuring that the peelable adhesive has a suitable viscosity and is easy to peel.

[0057] (3) The present invention uses butanone oxime as a catalyst and 3-aminopropyltriethoxysilane as an organosilicon modifier to modify polyurethane acrylate. After the modification is completed, the catalyst and by-products can be removed by distillation under high temperature and negative pressure conditions. The product has low odor, no small molecular volatiles, and good stability. DETAILED DESCRIPTION

[0058] In order to make the technical scheme of the present invention more clearly understood by those skilled in the art, the following embodiments are listed for illustration. It should be pointed out that the following embodiments do not limit the protection scope of the present invention.

[0059] Unless otherwise specified, the raw materials, reagents or devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0060] Example 1

[0061] A silicone-modified UV-curable peelable adhesive comprises 40 parts of silicone-modified polyurethane acrylate with a viscosity of 2700 mPa.s at 25°C, 15 parts of tetrahydrofuran acrylate, 10 parts of 2-phenoxyethyl acrylate, 2 parts of 1-hydroxycyclohexyl phenone, 3 parts of ethyl 2,4,6-trimethylbenzoylphosphonate, 0.3 parts of polydimethylsiloxane with a viscosity of 150 mPa.s at 25°C, 0.2 parts of polyoxyethylene alkylphenol ether, and 0.04 parts of phthalocyanine blue.

[0062] A method for preparing a silicone-modified UV-cured peelable adhesive comprises the following steps:

[0063] (1) adding silicone-modified polyurethane acrylate, tetrahydrofuran acrylate, 2-phenoxyethyl acrylate, 1-hydroxycyclohexyl phenone, and ethyl 2,4,6-trimethylbenzoylphosphonate in parts by weight into a planetary stirrer, and stirring at a stirring speed of 300 r / min for 100 min to obtain a mixture;

[0064] (2) Adding polydimethylsiloxane, polyoxyethylene alkylphenol ether and phthalocyanine blue to the mixture obtained in step (1) according to weight parts, stirring at a stirring speed of 500 r / min for 80 min; evacuating to a vacuum degree of -0.095 MPa, and stirring at a stirring speed of 200 r / min for 45 min to remove bubbles, thereby obtaining a silicone-modified UV LED-curable peelable adhesive.

[0065] The preparation method of silicone-modified polyurethane acrylate comprises the following steps:

[0066] (1) 70 parts of 2,4-toluene diisocyanate and 0.05 parts of dibutyltin dilaurate were added to a reaction kettle, the temperature was raised to 55° C., and stirred for 15 minutes; the temperature was further raised to 70° C., 35 parts of polypropylene glycol were added dropwise, and the mixture was stirred for 3.5 hours after the addition was completed to obtain a mixed solution; 60 parts of hydroxypropyl acrylate and 0.02 parts of para-oxymethylphenol were added to the mixed solution, the temperature was raised to 80° C., the mixture was stirred for 3.5 hours, and the mixture was cooled to obtain a polyurethane acrylate having a viscosity of 4100 mPa.s at 25° C.;

[0067] (2) Under nitrogen protection, add 2.5 parts of butanone oxime to the polyurethane acrylate obtained in step (1), stir at room temperature for 15 minutes, raise the temperature to 80° C., add 75 parts of 3-aminopropyltriethoxysilane dropwise, and stir for 2.5 hours after the addition is complete; raise the temperature to 180° C., distill at -0.095 MPa for 1.5 hours, and cool the material to obtain a silicone-modified polyurethane acrylate with a viscosity of 2700 mPa.s at 25° C.

[0068] Example 2

[0069] A silicone-modified UV-curable peelable adhesive comprises 30 parts of silicone-modified polyurethane acrylate with a viscosity of 4550 mPa.s at 25°C, 10 parts of isobornyl acrylate, 10 parts of 2-phenoxyethyl acrylate, 1 part of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 1 part of ethyl 2,4,6-trimethylbenzoylphosphonate, 0.05 parts of polymethylphenylsiloxane with a viscosity of 150 mPa.s at 25°C, 0.5 parts of polyoxyethylene alkylphenol ether, and 0.01 parts of cobalt blue.

[0070] A method for preparing a silicone-modified UV-cured peelable adhesive comprises the following steps:

[0071] (1) adding silicone-modified polyurethane acrylate, isobornyl acrylate, 2-phenoxyethyl acrylate, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, and ethyl 2,4,6-trimethylbenzoylphosphonate according to weight parts into a planetary stirrer, and stirring at a stirring speed of 250 r / min for 110 min to obtain a mixture;

[0072] (2) Adding polymethylphenylsiloxane, polyoxyethylene alkylphenol ether and cobalt blue to the mixture obtained in step (1) according to weight parts, stirring at a stirring speed of 450 r / min for 85 min; evacuating to a vacuum degree of -0.090 MPa, and stirring at a stirring speed of 150 r / min for 55 min to remove bubbles, thereby obtaining a silicone-modified UV LED-curable peelable adhesive.

[0073] The preparation method of silicone-modified polyurethane acrylate comprises the following steps:

[0074] (1) Add 65 parts of isophorone diisocyanate and 0.02 parts of stannous isooctanoate into a reaction kettle, heat to 50° C., stir for 20 min, raise the temperature to 75° C., dropwise add 25 parts of polypropylene glycol, and stir for 4 h after the dropwise addition to obtain a mixed solution; add 50 parts of hydroxypropyl acrylate and 0.05 parts of hydroquinone into the mixed solution, raise the temperature to 75° C., continue stirring for 3 h, and cool to obtain polyurethane acrylate with a viscosity of 4200 mPa.s at 25° C.;

[0075] (2) Under nitrogen protection, 3 parts of butanone oxime were added to the polyurethane acrylate obtained in step (1), and the mixture was stirred at room temperature for 10 min. The mixture was heated to 80° C., and 65 parts of 3-aminopropyltriethoxysilane were added dropwise. After the addition was completed, the mixture was stirred for 2 h. The mixture was heated to 170° C., and distilled at -0.090 MPa for 1 h. The mixture was cooled to obtain a silicone-modified polyurethane acrylate having a viscosity of 4550 mPa.s at 25° C.

[0076] Example 3

[0077] A silicone-modified UV-curable peelable adhesive comprises 50 parts of silicone-modified polyurethane acrylate with a viscosity of 5400 mPa.s at 25°C, 18 parts of dicyclopentadienyl acrylate, 10 parts of 2-dodecyl acrylate, 5 parts of 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 4 parts of 1-hydroxycyclohexyl phenyl ketone, 1 part of polydimethylsiloxane with a viscosity of 150 mPa.s at 25°C, 0.9 parts of alkylbenzene sulfonate, and 0.9 parts of iron blue.

[0078] A method for preparing a silicone-modified UV-cured peelable adhesive comprises the following steps:

[0079] (1) adding silicone-modified polyurethane acrylate, dicyclopentadienyl acrylate, 2-dodecyl acrylate, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, and 1-hydroxycyclohexyl phenone according to weight into a planetary stirrer, and stirring at a stirring speed of 380 r / min for 90 min to obtain a mixture;

[0080] (2) Adding polydimethylsiloxane, alkylbenzene sulfonate and iron blue to the mixture obtained in step (1) according to weight, stirring at a stirring speed of 550 r / min for 70 min; evacuating to a vacuum degree of -0.095 MPa, and stirring at a stirring speed of 250 r / min for 35 min to remove bubbles, thereby obtaining a silicone-modified UV LED-curable peelable adhesive.

[0081] The preparation method of silicone-modified polyurethane acrylate comprises the following steps:

[0082] (1) 80 parts of 2,4-toluene diisocyanate and 0.1 parts of zinc isooctanoate were added to a reaction kettle, the temperature was raised to 60° C., stirred for 20 min, the temperature was raised to 75° C., 40 parts of polypropylene glycol were added dropwise, and the mixture was stirred for 3 h after the addition was completed to obtain a mixed solution; 50 parts of hydroxypropyl acrylate and 0.1 parts of para-oxymethylphenol were added to the mixed solution, the temperature was raised to 85° C., the mixture was stirred for 3 h, and the mixture was cooled to obtain a polyurethane acrylate having a viscosity of 4670 mPa.s at 25° C.;

[0083] (2) Under nitrogen protection, 4 parts of butanone oxime were added to the polyurethane acrylate obtained in step (1), and the mixture was stirred at room temperature for 10 min. The mixture was heated to 75° C., and 60 parts of 3-aminopropyltriethoxysilane were added dropwise. After the addition was completed, the mixture was stirred for 2 h. The mixture was heated to 190° C., and distilled at -0.095 MPa for 2 h. The mixture was cooled and the resulting mixture was discharged to obtain a silicone-modified polyurethane acrylate having a viscosity of 5400 mPa.s at 25° C.

[0084] Comparative Example 1

[0085] The difference between Comparative Example 1 and Example 1 is that the polyurethane acrylate in Comparative Example 1 is not modified, and the viscosity of the unmodified polyurethane acrylate prepared is 4250 mPa.s. The other differences are the same as Example 1.

[0086] Comparative Example 2

[0087] The difference between Comparative Example 2 and Example 2 is that the polyurethane acrylate in Comparative Example 2 is not modified, and the viscosity of the prepared unmodified polyurethane acrylate is 4320 mPa.s. The rest is the same as Example 2.

[0088] Comparative Example 3

[0089] The difference between Comparative Example 3 and Example 3 is that the polyurethane acrylate in Comparative Example 3 is not modified, and the viscosity of the prepared unmodified polyurethane acrylate is 4800 mPa.s. The rest is the same as Example 3.

[0090] Comparative Example 4

[0091] The only difference between Comparative Example 4 and Example 3 is that Comparative Example 4 uses an equal amount of tetramethylammonium hydroxide to replace butanone oxime.

[0092] Comparative Example 5

[0093] The only difference between Comparative Example 5 and Example 3 is that Comparative Example 5 uses an equal amount of vinyltriethoxysilane to replace 3-aminopropyltriethoxysilane.

[0094] Performance Testing

[0095] The performance tests were conducted on the peelable adhesives of Examples 1-3 and Comparative Examples 1-5. The test results are shown in Tables 1 and 2.

[0096] Among them, the aging conditions for temperature resistance and weather resistance tests are: high temperature and high humidity (85℃×85%RH×24h: placed in an environment of 85℃ and 85% humidity for 24 hours) + high and low temperature impact (-40℃×30min-150℃×30min cycle for 24h: placed in a -40℃ environment for 30min, then placed in an environment of 150℃ for 30min, and alternately cycled for 24 hours).

[0097] Strippability test: Apply the strippable glue on the ITO glass with a thickness of 100μm and a width of 10mm. 2 , light intensity is 400mW / cm 2 , cure under UV LED conditions with a wavelength of 365nm, and peel off with tweezers after curing. If it is easy to peel off completely without breaking the glue, it proves that the peelability is good.

[0098] Table 1

[0099]

[0100]

[0101] Table 2

[0102]

[0103] As shown in Table 1, the peelable adhesives of Examples 1-3 of the present invention have no significant changes in peelability, adhesion, flexibility, tensile strength, and insulation before and after aging. This indicates that the present invention uses butanone oxime as a catalyst and 3-aminopropyltriethoxysilane as an organosilicon modifier to modify polyurethane acrylate to obtain organosilicon-modified polyurethane acrylate, and then through the combined action of organosilicon-modified polyurethane acrylate, monomer, and photoinitiator, the peelable adhesive has good temperature resistance and weather resistance, is easy to peel, and has a fast curing speed.

[0104] The rotational viscosity of the peelable adhesive of Comparative Examples 1-3 increased significantly, and its peelability, adhesion, flexibility, tensile strength, and insulation before and after aging all changed significantly. The insulation and flexibility after aging were worse than those of Examples 1-3, and the tensile strength and adhesion increased, making the peelable adhesive difficult to peel. It also shows that modifying the polyurethane acrylate in the process of preparing the peelable adhesive can make the peelable adhesive have good temperature resistance and weather resistance.

[0105] In Comparative Example 4, an equal amount of tetramethylammonium hydroxide is used to replace butanone oxime, so that after aging, the insulation and flexibility of the peelable adhesive of Comparative Example 4 are both deteriorated, the tensile strength is increased, and the adhesion is increased, which makes it difficult to peel off, that is, the temperature resistance and weather resistance of the peelable adhesive of Comparative Example 4 are poor. This shows that the use of butanone oxime as a catalyst to modify polyurethane acrylate can obtain a peelable adhesive with good temperature resistance and weather resistance.

[0106] Comparative Example 5 uses an equal amount of vinyl triethoxysilane to replace 3-aminopropyl triethoxysilane, so that after aging, the insulation and flexibility of the peelable adhesive of Comparative Example 5 are both deteriorated, and the adhesion and tensile strength are increased, which makes it difficult to peel off, that is, the temperature resistance and weather resistance of the peelable adhesive of Comparative Example 5 are poor. This shows that by using 3-aminopropyl triethoxysilane as a modifier to modify polyurethane acrylate, a peelable adhesive with good temperature resistance and weather resistance can be obtained.

[0107] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A peelable adhesive, characterized in that: Including silicone modified polyurethane acrylate, monomer, photoinitiator; The preparation method of the organosilicon-modified polyurethane acrylate comprises the following steps: (1) mixing diisocyanate and a catalyst, and adding polypropylene glycol to prepare a mixed solution; (2) adding hydroxypropyl acrylate and a polymerization inhibitor to the mixed solution obtained in step (1) to prepare polyurethane acrylate; (3) adding butanone oxime and 3-aminopropyltriethoxysilane to the polyurethane acrylate obtained in step (2), and distilling to obtain the organosilicon-modified polyurethane acrylate; The monomers include acrylic ester monomers.

2. The peelable adhesive according to claim 1, characterized in that: The strippable adhesive further comprises at least one of a leveling agent, a dispersant and a pigment.

3. The peelable adhesive according to claim 2, characterized in that: In parts by weight, the strippable adhesive comprises 27-55 parts of organosilicon-modified polyurethane acrylate, 18-33 parts of monomer, 1-12 parts of photoinitiator, 0.01-1.2 parts of leveling agent, 0.08-1.2 parts of dispersant and 0.01-1.2 parts of pigment.

4. The peelable adhesive according to claim 1, characterized in that: The monomer is selected from at least one of 2-phenoxyethyl acrylate, tetrahydrofuran acrylate, isobornyl acrylate, dicyclopentadienyl acrylate, 2-dodecyl acrylate, 3.3.5-trimethylcyclohexyl acrylate and 1,6-hexanediol dimethacrylate.

5. The peelable adhesive according to claim 1, characterized in that: The photoinitiator is selected from at least one of 1-hydroxycyclohexyl phenyl ketone, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, ethyl 2,4,6-trimethylbenzoylphosphonate, and phenylbis(2,4,6-trimethylbenzoyl)oxybenzoylformate.

6. The method for preparing the peelable adhesive according to any one of claims 1 to 5, characterized in that: The following steps are involved: The peelable adhesive is prepared by mixing various raw material components and performing vacuum degassing.

7. The preparation method according to claim 6, characterized in that: The vacuum degassing process is stirred; the stirring speed is 90-330 r / min, and the stirring time is 27-65 min.

8. The preparation method according to claim 6, characterized in that: In parts by weight, the added amounts of the raw material components of the silicone-modified polyurethane acrylate are: 60-88 parts of diisocyanate, 0.02-0.12 parts of catalyst, 18-44 parts of polypropylene glycol, 45-65 parts of hydroxypropyl acrylate, 0.02-0.12 parts of polymerization inhibitor, 1.8-4.4 parts of butanone oxime, and 55-88 parts of 3-aminopropyltriethoxysilane.

9. Use of the peelable adhesive according to any one of claims 1 to 5 in the field of electronics.

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