A kind of thermal reaction adhesive tape and preparation method thereof

Abstract

The invention discloses a kind of heat reaction adhesive tape and preparation method thereof, relate to the technical field of adhesive, include release layer and adhesive film layer, the adhesive film layer is made of the following raw materials: 100 parts of aqueous polyurethane dispersion, 8-20 parts of blocked isocyanate curing agent, 20-30 parts of hyperbranched aqueous polyurethane, 3-8 parts of thickener, 1-5 parts of defoamer, 1-3 parts of wetting agent, 3-5 parts of zwitterionic surfactant, 10-20 parts of functional copolymer, 40-60 parts of water; the functional copolymer includes structural units introduced by N-trimethylol methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide, respectively. The adhesive tape has good adhesion, good high temperature and humidity aging performance, sufficient environmental protection, and long service life.

Description

Technical Field

[0001] The present invention relates to the technical field of adhesives, and in particular to a thermal reaction tape and a preparation method thereof. Background Art

[0002] Thermal reaction tape is a special tape that becomes sticky under certain temperature conditions and is a representative type of hot melt tape. The tape is thin-film-like at room temperature and has no stickiness. It is activated to produce a cross-linking reaction to form a high bonding force only when a specific temperature and bonding pressure are applied. Because it combines chemical corrosion resistance and aging resistance, it still performs well under harsh environmental conditions. It has the advantages of affinity to substrates, high adhesion, convenient storage and environmental protection. It is widely used in the lamination of plastics and other materials and textiles in the fields of protective covers for electronic products, home furnishings, shoes and clothing.

[0003] The existing common heat-reactive adhesive tapes are easy to leave residual adhesive on the surface of the adherend, have low peel strength, low initial adhesion, high defective rate of finished products, poor wettability to the laminated material, often have poor adhesion, debonding, degumming and other inferior conditions, and the heat aging resistance needs to be further improved. In order to solve the above technical problems, the Chinese invention patent with the authorization announcement number CN108250993B discloses a formula and preparation method of a substrate-free low-temperature reactive hot melt adhesive tape, which is composed of substrate-free dry glue and double-sided release film or release paper. The glue is composed of 100-150 parts of thermoplastic polyurethane, 50-150 parts of rosin glycerol ester, 1-40 parts of blocked crosslinking agent, 1-10 parts of wetting and leveling agent, 1-10 parts of defoaming agent, 1-10 parts of rheological agent, 0.1-5 parts of anti-aging agent, 100-400 parts of ketone and ester mixed solvent, which is coated on the substrate and then dried, rolled and cut. This product has high bonding strength. However, it uses organic solvents, has poor environmental performance, and its high temperature and high humidity aging resistance still needs to be further improved.

[0004] It can be seen that the development of a thermal reactive tape with good adhesion, good high temperature and high humidity aging resistance, sufficient environmental protection, and long service life and its preparation method meets market demand, has broad market value and application prospects, and is of great significance to promoting the development of the field of thermal reactive tapes. Summary of the invention

[0005] The main purpose of the present invention is to provide a thermal reaction tape with good adhesion, good high temperature and high humidity aging resistance, sufficient environmental protection and long service life and a preparation method thereof.

[0006] To achieve the above purpose, the present invention provides a thermal reaction tape, comprising a release layer and an adhesive film layer, wherein the adhesive film layer is made of the following raw materials in parts by weight: 100 parts of an aqueous polyurethane dispersion, 8-20 parts of a blocked isocyanate curing agent, 20-30 parts of a hyperbranched aqueous polyurethane, 3-8 parts of a thickener, 1-5 parts of a defoamer, 1-3 parts of a wetting agent, 3-5 parts of a zwitterionic surfactant, 10-20 parts of a functional copolymer, and 40-60 parts of water; the functional copolymer comprises structural units introduced by free radical polymerization of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl(4-vinylphenyl)phosphine oxide.

[0007] Preferably, the aqueous polyurethane dispersion contains any one or more of three types of active groups: amino, carboxyl and hydroxyl. More preferably, the aqueous polyurethane dispersion is Bayhydrol® U 2757 provided by Covestro.

[0008] Preferably, the blocked isocyanate curing agent is selected from at least one of the low-temperature unblocking blocked isocyanate curing agent PT-1080Y provided by Guangzhou Lvbao New Materials Co., Ltd., and the low-temperature blocked curing agent Curingelf® S-860N and Curingelf® S-870N produced by Lewis Chemical of the United States.

[0009] Preferably, there is no special requirement for the source of the hyperbranched waterborne polyurethane. In one embodiment of the present invention, the hyperbranched waterborne polyurethane is prepared according to the method of Example 1 of the Chinese invention patent with authorization announcement number CN102352011B, and the amount used is the amount of pure substance not dispersed with water.

[0010] Preferably, the thickener is at least one of hydroxyethyl cellulose, guar gum and xanthan gum.

[0011] Preferably, the defoamer is at least one of Evonik Degussa TEGO Foamex 3062 aqueous defoamer and TEGO Foamex 1488 defoamer.

[0012] Preferably, the wetting agent is Evonik Degussa TEGO Twin 4200 wetting agent.

[0013] Preferably, the zwitterionic surfactant is dodecyl dimethyl betaine.

[0014] Preferably, the preparation method of the functional copolymer comprises the following steps: adding N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketoxime) silane, isopropenylboronic acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide, and an initiator to a high boiling point solvent, stirring and reacting at 60-70° C. in an inert gas atmosphere for 3-5 hours, then removing the solvent by rotary evaporation, dissolving the crude product in water, taking the supernatant and placing it in a dialysis bag, placing the dialysis bag in water for 20-30 hours, and then removing the water in the dialysis bag by rotary evaporation to obtain a functional copolymer.

[0015] Preferably, the mass ratio of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methylvinylbis(butyl ketoxime)silane, isopropenylboronic acid pinacol ester, diphenyl(4-vinylphenyl)phosphine oxide, initiator, and high boiling point solvent is (3-5):0.5:(0.8-1.2):0.3:(0.1-0.3):(0.05-0.08):(0.1-0.3).

[0016] Preferably, the initiator is azobisisobutyronitrile; the high boiling point solvent is at least one of dimethyl sulfoxide, N,N-dimethylformamide, and N-methylpyrrolidone; and the inert gas is any one of nitrogen, helium, neon, and argon.

[0017] Another object of the present invention is to provide a method for preparing the thermal reactive adhesive tape, comprising the following steps:

[0018] Step S1, preparation: uniformly mix the raw materials according to weight to obtain a glue mixture;

[0019] Step S2, filtering and degassing: the glue mixture is passed through a 100-300 mesh sieve, and then degassing is performed using a vacuum degassing machine, the vacuum degree is set to -0.060 to -0.080 MPa, and the degassing time is 25 to 35 minutes. After the degassing is completed, the glue for the thermal reaction tape can be obtained;

[0020] Step S3, coating and drying: the heat-reactive adhesive tape prepared in step S2 is evenly coated on the release paper by a comma scraper or anilox roller, and freeze-dried to obtain a heat-reactive adhesive tape with a glue layer thickness of 0.005-0.200 mm.

[0021] Due to the application of the above technical solution, the present invention has the following beneficial effects:

[0022] (1) The preparation method of the heat-responsive adhesive tape disclosed in the present invention has simple process, convenient operation and control, high preparation efficiency and finished product qualification rate, low dependence on equipment, suitable for industrial production, high promotion and application value, and significant economic and social benefits.

[0023] (2) The heat-reactive adhesive tape disclosed in the present invention comprises an adhesive film layer made of the following raw materials in parts by weight: 100 parts of aqueous polyurethane dispersion, 8-20 parts of blocked isocyanate curing agent, 20-30 parts of hyperbranched aqueous polyurethane, 3-8 parts of thickener, 1-5 parts of defoamer, 1-3 parts of wetting agent, 3-5 parts of zwitterionic surfactant, 10-20 parts of functional copolymer and 40-60 parts of water. Through the mutual coordination and joint action of the raw materials, the heat-reactive adhesive tape has good adhesion, good high temperature and high humidity aging resistance, good environmental protection and long service life.

[0024] (3) The thermal reactive adhesive tape disclosed in the present invention has a functional copolymer containing structural units introduced by free radical polymerization of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl (4-vinylphenyl) phosphine oxide. The coexistence of hydroxyl, amide, fluoroquinoxalinone, silane, boric acid pinacol ester, and phenyl phosphine oxide structures, together with the hyperbranched polyurethane structure, can give the product better adhesion, high temperature and high humidity aging resistance, and water boiling resistance under the multiple effects of electronic effect, steric effect, and conjugation effect, thereby extending the service life.

[0025] (4) The thermal reaction tape disclosed in the present invention uses water as a dispersion system, which is more environmentally friendly. The thermal reaction tape has good storage stability through freeze drying and reasonable selection of a blocked isocyanate curing agent. The hydroxyl groups on the functional copolymer and the active groups in the polyurethane molecular structure can undergo a curing reaction with the blocked isocyanate curing agent above the unblocking temperature to form an interpenetrating network structure, which effectively improves the product's adhesion, high temperature and high humidity aging resistance, and water boiling resistance, thereby extending its service life. DETAILED DESCRIPTION

[0026] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations. Example 1

[0027] A thermal reaction tape comprises a release layer and an adhesive film layer, wherein the adhesive film layer is made of the following raw materials in parts by weight: 100 parts of aqueous polyurethane dispersion, 8 parts of blocked isocyanate curing agent, 20 parts of hyperbranched aqueous polyurethane, 3 parts of thickener, 1 part of defoamer, 1 part of wetting agent, 3 parts of zwitterionic surfactant, 10 parts of functional copolymer, and 40 parts of water; the functional copolymer comprises structural units respectively introduced by free radical polymerization reaction of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl (4-vinylphenyl) phosphine oxide.

[0028] The waterborne polyurethane dispersion is Bayhydrol® U2757 provided by Covestro; the blocked isocyanate curing agent is selected from the low-temperature deblocking blocked isocyanate curing agent PT-1080Y provided by Guangzhou Lvbao New Materials Co., Ltd.; the hyperbranched waterborne polyurethane is prepared according to the method of Example 1 of the Chinese invention patent with authorization announcement number CN102352011B, and its amount is the amount of pure substance not dispersed with water.

[0029] The thickener is hydroxyethyl cellulose; the defoamer is Evonik Degussa TEGO Foamex 3062 water-based defoamer; the wetting agent is Evonik Degussa TEGO Twin 4200 wetting agent; and the zwitterionic surfactant is dodecyl dimethyl betaine.

[0030] The preparation method of the functional copolymer comprises the following steps: adding N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketoxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide and an initiator to a high boiling point solvent, stirring and reacting at 60°C for 3 hours in an inert gas atmosphere, then removing the solvent by rotary evaporation, dissolving the crude product in water, taking the supernatant and placing it in a dialysis bag, placing the dialysis bag in water for 20 hours, and then removing the solvent in the dialysis bag by rotary evaporation. water to obtain a functional copolymer; the mass ratio of N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketone oxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide, initiator, and high boiling point solvent is 3:0.5:0.8:0.3:0.1:0.05:0.1; the initiator is azobisisobutyronitrile; the high boiling point solvent is dimethyl sulfoxide; the inert gas is nitrogen; the M of the copolymer is measured by GPC test. n =13372g / mol,M W / Mn =1.253; through elemental analysis and calculation, the mass ratio of the structural units introduced by N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl (4-vinylphenyl) phosphine oxide in the copolymer is 2.97:0.49:0.78:0.29:0.1.

[0031] A method for preparing the thermal reactive adhesive tape comprises the following steps:

[0032] Step S1, preparation: uniformly mix the raw materials according to weight to obtain a glue mixture;

[0033] Step S2, filtering and degassing: the glue mixture is passed through a 100-mesh sieve, and then degassing is performed using a vacuum degassing machine, the vacuum degree is set to -0.060 MPa, and the degassing time is 25 minutes. After the degassing is completed, glue for thermal reaction tape can be obtained;

[0034] Step S3, coating and drying: the glue of the thermal reaction tape prepared in step S2 is evenly coated on the release paper by using a comma scraper, and freeze-dried to obtain a thermal reaction tape with a glue layer thickness of 0.1 mm. Example 2

[0035] A thermal reaction adhesive tape comprises a release layer and an adhesive film layer, wherein the adhesive film layer is made of the following raw materials in parts by weight: 100 parts of aqueous polyurethane dispersion, 10 parts of blocked isocyanate curing agent, 23 parts of hyperbranched aqueous polyurethane, 5 parts of thickener, 2 parts of defoamer, 1.5 parts of wetting agent, 3.5 parts of zwitterionic surfactant, 12 parts of functional copolymer, and 45 parts of water; the functional copolymer comprises structural units respectively introduced by free radical polymerization reaction of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl (4-vinylphenyl) phosphine oxide.

[0036] The waterborne polyurethane dispersion is Bayhydrol® U2757 provided by Covestro; the blocked isocyanate curing agent is selected from the low-temperature blocked curing agent Curingelf® S-860N produced by Lewis Chemical of the United States; the hyperbranched waterborne polyurethane is prepared according to the method of Example 1 of the Chinese invention patent with the authorization announcement number CN102352011B, and its amount is the amount of pure substance not dispersed with water; the thickener is guar gum; the defoamer is Evonik Degussa TEGO Foamex 1488 defoamer; the wetting agent is Evonik Degussa TEGO Twin 4200 wetting agent; the zwitterionic surfactant is dodecyl dimethyl betaine.

[0037] The preparation method of the functional copolymer comprises the following steps: adding N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketone oxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide and an initiator to a high boiling point solvent, stirring and reacting at 63°C in an inert gas atmosphere for 3-5 hours, then removing the solvent by rotary evaporation, dissolving the crude product in water, taking the supernatant and placing it in a dialysis bag, placing the dialysis bag in water for dialysis for 20-30 hours, and then removing the supernatant by rotary evaporation. The water in the dialysis bag is removed to obtain a functional copolymer; the mass ratio of N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketone oxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide, initiator, and high boiling point solvent is 3.5:0.5:0.9:0.3:0.15:0.06:0.15; the initiator is azobisisobutyronitrile; the high boiling point solvent is N,N-dimethylformamide; and the inert gas is helium.

[0038] A method for preparing the thermal reactive adhesive tape comprises the following steps:

[0039] Step S1, preparation: uniformly mix the raw materials according to weight to obtain a glue mixture;

[0040] Step S2, filtering and degassing: the glue mixture is passed through a 150-mesh sieve, and then degassing is performed using a vacuum degassing machine, the vacuum degree is set to -0.065 MPa, and the degassing time is 27 minutes. After the degassing is completed, glue for thermal reaction tape can be obtained;

[0041] Step S3, coating and drying: The heat-reactive adhesive tape prepared in step S2 is evenly coated on the release paper by an anilox roller, and freeze-dried to obtain a heat-reactive adhesive tape with a glue layer thickness of 0.1 mm. Example 3

[0042] A thermal reaction tape comprises a release layer and an adhesive film layer, wherein the adhesive film layer is made of the following raw materials in parts by weight: 100 parts of aqueous polyurethane dispersion, 13 parts of blocked isocyanate curing agent, 25 parts of hyperbranched aqueous polyurethane, 5.5 parts of thickener, 3.5 parts of defoamer, 2 parts of wetting agent, 4 parts of zwitterionic surfactant, 15 parts of functional copolymer, and 50 parts of water; the functional copolymer comprises structural units respectively introduced by free radical polymerization reaction of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl (4-vinylphenyl) phosphine oxide.

[0043] The waterborne polyurethane dispersion is Bayhydrol® U2757 provided by Covestro; the blocked isocyanate curing agent is selected from the low-temperature blocked curing agent Curingelf® S-870N produced by Lewis Chemical of the United States; the hyperbranched waterborne polyurethane is prepared according to the method of Example 1 of the Chinese invention patent with the authorization announcement number CN102352011B, and the amount used is the amount of pure substance not dispersed with water; the thickener is xanthan gum; the defoamer is Evonik Degussa TEGO Foamex 3062 water-based defoamer; the wetting agent is Evonik Degussa TEGO Twin 4200 wetting agent; and the zwitterionic surfactant is dodecyl dimethyl betaine.

[0044] The preparation method of the functional copolymer comprises the following steps: adding N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketone oxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide and an initiator to a high boiling point solvent, stirring and reacting at 65°C for 4 hours in an inert gas atmosphere, then removing the solvent by rotary evaporation, dissolving the crude product in water, taking the supernatant and placing it in a dialysis bag, placing the dialysis bag in water for 25 hours, and then rotary evaporation. The water in the dialysis bag is removed to obtain a functional copolymer; the mass ratio of N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketone oxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide, initiator, and high boiling point solvent is 4:0.5:1:0.3:0.2:0.065:0.2; the initiator is azobisisobutyronitrile; the high boiling point solvent is N-methylpyrrolidone; and the inert gas is neon.

[0045] A method for preparing the thermal reactive adhesive tape comprises the following steps:

[0046] Step S1, preparation: uniformly mix the raw materials according to weight to obtain a glue mixture;

[0047] Step S2, filtering and degassing: the glue mixture is passed through a 200-mesh sieve, and then degassing is performed using a vacuum degassing machine, the vacuum degree is set to -0.070 MPa, and the degassing time is 30 minutes. After the degassing is completed, glue for thermal reaction tape can be obtained;

[0048] Step S3, coating and drying: the glue of the thermal reaction tape prepared in step S2 is evenly coated on the release paper by using a comma scraper, and freeze-dried to obtain a thermal reaction tape with a glue layer thickness of 0.1 mm. Example 4

[0049] A thermal reaction adhesive tape comprises a release layer and an adhesive film layer, wherein the adhesive film layer is made of the following raw materials in parts by weight: 100 parts of aqueous polyurethane dispersion, 18 parts of blocked isocyanate curing agent, 28 parts of hyperbranched aqueous polyurethane, 7 parts of thickener, 4 parts of defoamer, 2.5 parts of wetting agent, 4.5 parts of zwitterionic surfactant, 18 parts of functional copolymer, and 55 parts of water; the functional copolymer comprises structural units respectively introduced by free radical polymerization reaction of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl (4-vinylphenyl) phosphine oxide.

[0050] The waterborne polyurethane dispersion is Bayhydrol® U2757 provided by Covestro; the blocked isocyanate curing agent is a mixture of the low-temperature unblocked blocked isocyanate curing agent PT-1080Y provided by Guangzhou Green Protection New Materials Co., Ltd., the low-temperature blocked curing agent Curingelf® S-860N and Curingelf® S-870N produced by Lewis Chemical of the United States, in a mass ratio of 1:2:3; the hyperbranched waterborne polyurethane is prepared according to the method of Example 1 of the Chinese invention patent with the authorization announcement number CN102352011B, and its amount is the amount of pure substance not dispersed with water; the thickener is a mixture of hydroxyethyl cellulose, guar gum and xanthan gum in a mass ratio of 1:2:1; the defoamer is a mixture of Evonik Degussa TEGO Foamex 3062 water-based defoamer and TEGO Foamex 1488 defoamer in a mass ratio of 3:5; the wetting agent is Evonik Degussa TEGO Twin 4200 wetting agent; the zwitterionic surfactant is dodecyl dimethyl betaine.

[0051] The preparation method of the functional copolymer comprises the following steps: adding N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketoxime) silane, isopropenylboronic acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide and an initiator to a high boiling point solvent, stirring and reacting at 68°C for 4.5 hours in an inert gas atmosphere, then removing the solvent by rotary evaporation, dissolving the crude product in water, taking the supernatant and placing it in a dialysis bag, placing the dialysis bag in water for dialysis for 28 hours, and then removing the water in the dialysis bag by rotary evaporation to obtain the functional copolymer; The mass ratio of N-trihydroxymethylacrylamide, 3-(1,1-difluoro-2-propene-1-yl)-2(1H)-quinoxalinone, methylvinylbis(butanone oxime)silane, isopropenylboronic acid pinacol ester, diphenyl(4-vinylphenyl)phosphine oxide, initiator and high boiling point solvent is 4.5:0.5:1.1:0.3:0.25:0.075:0.25; the initiator is azobisisobutyronitrile; the high boiling point solvent is a mixture of dimethyl sulfoxide, N,N-dimethylformamide and N-methylpyrrolidone in a mass ratio of 2:3:5; the inert gas is argon.

[0052] A method for preparing the thermal reactive adhesive tape comprises the following steps:

[0053] Step S1, preparation: uniformly mix the raw materials according to weight to obtain a glue mixture;

[0054] Step S2, filtering and degassing: the glue mixture is passed through a 250-mesh sieve, and then degassing is performed using a vacuum degassing machine, the vacuum degree is set to -0.075 MPa, and the degassing time is 33 minutes. After the degassing is completed, glue for thermal reaction tape can be obtained;

[0055] Step S3, coating and drying: The heat-reactive adhesive tape prepared in step S2 is evenly coated on the release paper by an anilox roller, and freeze-dried to obtain a heat-reactive adhesive tape with a glue layer thickness of 0.1 mm. Example 5

[0056] A thermal reaction tape comprises a release layer and an adhesive film layer, wherein the adhesive film layer is made of the following raw materials in parts by weight: 100 parts of aqueous polyurethane dispersion, 20 parts of blocked isocyanate curing agent, 30 parts of hyperbranched aqueous polyurethane, 8 parts of thickener, 5 parts of defoamer, 3 parts of wetting agent, 5 parts of zwitterionic surfactant, 20 parts of functional copolymer, and 60 parts of water; the functional copolymer comprises structural units respectively introduced by free radical polymerization reaction of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl (4-vinylphenyl) phosphine oxide.

[0057] The waterborne polyurethane dispersion is Bayhydrol® U2757 provided by Covestro; the blocked isocyanate curing agent is selected from the low-temperature blocked curing agent Curingelf® S-860N produced by Lewis Chemical of the United States; the hyperbranched waterborne polyurethane is prepared according to the method of Example 1 of the Chinese invention patent with the authorization announcement number CN102352011B, and the amount used is the amount of pure substance not dispersed with water; the thickener is hydroxyethyl cellulose; the defoamer is Evonik Degussa TEGO Foamex 3062 water-based defoamer; the wetting agent is Evonik Degussa TEGO Twin 4200 wetting agent; and the zwitterionic surfactant is dodecyl dimethyl betaine.

[0058] The preparation method of the functional copolymer comprises the following steps: adding N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketoxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide and an initiator to a high boiling point solvent, stirring and reacting at 70°C in an inert gas atmosphere for 5 hours, then evaporating to remove the solvent, dissolving the crude product in water, taking the supernatant and placing it in a dialysis bag, placing the dialysis bag in water for 30 hours, and then evaporating to remove the solvent, dissolving the crude product in water, taking the supernatant and placing it in a dialysis bag, placing the dialysis bag in water for dialysis, and ... The water in the dialysis bag is evaporated to obtain a functional copolymer; the mass ratio of N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide, initiator, and high boiling point solvent is 5:0.5:1.2:0.3:0.3:0.08:0.3; the initiator is azobisisobutyronitrile; the high boiling point solvent is dimethyl sulfoxide; and the inert gas is nitrogen.

[0059] A method for preparing the thermal reactive adhesive tape comprises the following steps:

[0060] Step S1, preparation: uniformly mix the raw materials according to weight to obtain a glue mixture;

[0061] Step S2, filtering and degassing: the glue mixture is passed through a 300-mesh sieve, and then degassing is performed using a vacuum degassing machine, the vacuum degree is set to -0.080 MPa, and the degassing time is 35 minutes. After the degassing is completed, glue for thermal reaction tape can be obtained;

[0062] Step S3, coating and drying: the glue of the thermal reaction tape prepared in step S2 is evenly coated on the release paper by using a comma scraper, and freeze-dried to obtain a thermal reaction tape with a glue layer thickness of 0.1 mm.

[0063] Comparative Example 1

[0064] A thermal reaction tape and a preparation method thereof, which are substantially the same as those in Example 1, except that no hyperbranched waterborne polyurethane and 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone are added.

[0065] Comparative Example 2

[0066] A thermal reaction adhesive tape and a preparation method thereof, which are substantially the same as those in Example 1, except that isopropenylboronic acid pinacol ester and diphenyl (4-vinylphenyl) phosphine oxide are not added.

[0067] In order to further illustrate the beneficial technical effects of the heat-reactive tapes involved in the embodiments of the present invention, the heat-reactive tapes prepared in Examples 1-5 and Comparative Examples 1-2 were subjected to relevant performance tests. The test results are shown in Table 1. The test method is as follows: (1) The peel strength test between the tape and stainless steel at room temperature (23°C) was carried out according to the method of GB / T 2792-2014. When laminating, the hot pressing temperature was set to 100°C, the pressure was 6 bar, and the time was 90 s; (2) High temperature and high humidity aging resistance is to place each sample in a constant temperature and humidity test chamber at 85℃*85%RH for 168 hours, cool to room temperature, and then test the 180° peel strength with stainless steel according to the test method of peel strength in (1), and calculate the peel strength retention rate. The larger the value, the better the high temperature and high humidity aging resistance; (3) Water boiling resistance is to place each sample in a constant temperature water bath at 90℃ for 2 hours, cool to room temperature, and then test the 180° peel strength with stainless steel according to the test method of peel strength in (1), and calculate the peel strength retention rate. The larger the value, the better the water boiling resistance.

[0068] Table 1

[0069] project 180° peel strength (N / cm) High temperature and high humidity aging resistance (%) Boiling resistance (%) Example 1 20.8 97.9 98.8 Example 2 21.3 98.5 99.1 Example 3 21.6 98.7 99.4 Example 4 22.0 99.1 99.6 Example 5 22.7 99.6 99.8 Comparative Example 1 18.4 96.0 97.2 Comparative Example 2 20.2 94.7 95.4

[0070] It can be seen from Table 1 that the thermal reaction tapes disclosed in the embodiments of the present invention have better bonding performance, high temperature and high humidity aging resistance and water boiling resistance than the comparative example products; the addition of hyperbranched waterborne polyurethane, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, isopropenylboronic acid pinacol ester and diphenyl(4-vinylphenyl)phosphine oxide is beneficial to improving the above properties.

[0071] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A heat-reactive adhesive tape, characterized in that: The invention comprises a release layer and an adhesive film layer, wherein the adhesive film layer is made of the following raw materials in parts by weight: 100 parts of an aqueous polyurethane dispersion, 8-20 parts of a blocked isocyanate curing agent, 20-30 parts of a hyperbranched aqueous polyurethane, 3-8 parts of a thickener, 1-5 parts of a defoamer, 1-3 parts of a wetting agent, 3-5 parts of a zwitterionic surfactant, 10-20 parts of a functional copolymer, and 40-60 parts of water; the functional copolymer comprises structural units introduced by free radical polymerization reaction of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butanone oxime) silane, isopropenyl boric acid pinacol ester, and diphenyl(4-vinylphenyl)phosphine oxide; The preparation method of the functional copolymer comprises the following steps: adding N-trihydroxymethyl methacrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketoxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide and an initiator into a high boiling point solvent, stirring and reacting at 60-70° C. for 3-5 hours in an inert gas atmosphere, then removing the solvent by rotary evaporation, dissolving the crude product in water, taking the supernatant and placing it in a dialysis bag, and placing the dialysis bag in water for 2 hours. 0-30h, and then remove the water in the dialysis bag by rotary evaporation to obtain a functional copolymer; the mass ratio of N-trimethylolmethyl acrylamide, 3-(1,1-difluoro-2-propylene-1-yl)-2(1H)-quinoxalinone, methyl vinyl di(butyl ketone oxime) silane, isopropenyl boric acid pinacol ester, diphenyl (4-vinylphenyl) phosphine oxide, initiator, and high boiling point solvent is (3-5): 0.5: (0.8-1.2): 0.3: (0.1-0.3): (0.05-0.08): (0.1-0.3).

2. The heat-reactive adhesive tape according to claim 1, characterized in that: The waterborne polyurethane dispersion contains any one or more of three types of active groups: amino, carboxyl and hydroxyl.

3. The heat-reactive adhesive tape according to claim 1, characterized in that: The aqueous polyurethane dispersion is the aqueous polyurethane dispersion Bayhydrol® U 2757.

4. The heat-reactive adhesive tape according to claim 1, characterized in that: The blocked isocyanate curing agent is selected from at least one of the low-temperature unblocking blocked isocyanate curing agent PT-1080Y, the low-temperature blocked curing agent Curingelf® S-860N, and Curingelf® S-870N.

5. The heat-reactive adhesive tape according to claim 1, characterized in that: The thickener is at least one of hydroxyethyl cellulose, guar gum and xanthan gum; the defoamer is at least one of TEGO Foamex 3062 aqueous defoamer and TEGO Foamex 1488 defoamer.

6. The heat-reactive adhesive tape according to claim 1, characterized in that: The wetting agent is TEGO Twin 4200 wetting agent; the zwitterionic surfactant is dodecyl dimethyl betaine.

7. The heat-reactive adhesive tape according to claim 1, characterized in that: The initiator is azobisisobutyronitrile; the high boiling point solvent is at least one of dimethyl sulfoxide, N,N-dimethylformamide, and N-methylpyrrolidone; and the inert gas is any one of nitrogen, helium, neon, and argon.

8. A method for preparing the heat-reactive adhesive tape according to any one of claims 1 to 7, characterized in that: The steps include: Step S1, preparation: uniformly mix the raw materials according to weight to obtain a glue mixture; Step S2, filtering and degassing: the glue mixture is passed through a 100-300 mesh sieve, and then degassing is performed using a vacuum degassing machine, the vacuum degree is set to -0.060 to -0.080 MPa, and the degassing time is 25 to 35 minutes. After the degassing is completed, the glue for the thermal reaction tape can be obtained; Step S3, coating and drying: the heat-reactive adhesive tape prepared in step S2 is evenly coated on the release paper by a comma scraper or anilox roller, and freeze-dried to obtain a heat-reactive adhesive tape with a glue layer thickness of 0.005-0.200 mm.