Modified butyl rubber, self-repairing butyl hot melt adhesive for photovoltaic module and preparation method of modified butyl rubber

Abstract

The invention relates to modified butyl rubber, a self-repairing butyl hot melt adhesive for a photovoltaic module and a preparation method of the modified butyl rubber. The modified butyl rubber is obtained by sequentially reacting halogenated butyl rubber with a hydroxyl olefine acid compound and hydrogen-containing silane; the structural formula of the hydroxyl olefine acid compound is HO (CH2) mCH = CHCOOH, and m is selected from 2, 3, 4, 5, 6, 7 and 8; the structural formula of the hydrogen-containing silane is HSi (R1) (OR2) 2, R1 is selected from C1-C6 alkoxy and C1-C6 alkyl, and R2 is selected from C1-C6 alkyl. The self-repairing butyl hot melt adhesive for the photovoltaic module is prepared from the modified butyl rubber and other raw materials. The butyl hot melt adhesive disclosed by the invention has the advantages of good cohesiveness with a glass interface, high strength, good mechanical properties, high water vapor barrier rate and excellent self-repairing performance, and can be used in the field of photovoltaic modules.

Description

Technical Field

[0001] The present invention belongs to the technical field of sealants, and in particular relates to a modified butyl rubber, a self-repairing butyl hot melt adhesive for photovoltaic modules and a preparation method thereof. Background Art

[0002] The regular molecular structure of butyl rubber gives it excellent air tightness and very low water vapor permeability. It is widely used in the airtight layer of tire inner tubes, the first seal of insulating glass, building waterproof membranes, special waterproof tapes, photovoltaic modules and other fields.

[0003] Among them, butyl hot melt adhesive is a single-component, solvent-free, non-fogging, non-vulcanized thermoplastic material based on butyl rubber and polyisobutylene. It is used as the first water-blocking edge sealant in the field of photovoltaic modules, especially in perovskite and heterojunction photovoltaic modules that are sensitive to water vapor. The dense arrangement of side methyl groups in the molecular chain of butyl rubber limits the thermal motion of polymer molecules, reduces the flexibility of the chain, and produces trace crystals. These structural characteristics make butyl rubber have excellent weather resistance, heat resistance, alkali resistance, low water vapor permeability, good air tightness, and its air permeability is one order of magnitude lower than that of natural rubber. However, the bonding effect of butyl rubber and glass interface is still not ideal. The bonding force is easy to decrease after aging. There are problems such as lack of glue and delamination after aging under ultraviolet, damp heat, high and low temperature, and poor water vapor barrier rate. It cannot be guaranteed that the sealing tape has a long-lasting water vapor barrier effect during use.

[0004] In addition, improper construction operations or mistakes during the use of sealants may easily cause sealant damage, defects or bubbles, resulting in a decrease in the mechanical properties of butyl hot melt sealants. In severe cases, the sealing performance may fail, greatly reducing the service life of photovoltaic modules. In addition, butyl hot melt sealants themselves do not have the ability to repair damage. As an edge sealing system, this greatly reduces the product qualification rate. Summary of the invention

[0005] Based on this, the purpose of the present invention is to provide a self-repairing butyl hot melt adhesive for photovoltaic modules with good bonding effect.

[0006] The technical solutions for achieving the above-mentioned purpose include the following.

[0007] The first aspect of the present invention is to provide a modified butyl rubber, which is obtained by reacting halogenated butyl rubber with a hydroxy olefinic acid compound and a hydrogen-containing silane in sequence;

[0008] The structural formula of the hydroxy olefinic acid compound is HO(CH2) m CH=CHCOOH, wherein m is selected from: 2, 3, 4, 5, 6, 7, 8;

[0009] The structural formula of the hydrogen-containing silane is HSi(R1)(OR2)2, wherein R1 is selected from: C1-C6 alkoxy, C1-C6 alkyl, and R2 is selected from: C1-C6 alkyl.

[0010] In some embodiments, the halogenated butyl rubber is brominated butyl rubber and / or chlorinated butyl rubber.

[0011] In some embodiments, the raw rubber Mooney viscosity ML of the halogenated butyl rubber is 1+8 It is 27 to 50, preferably 30 to 40.

[0012] In some of the embodiments, the mass content of halogen groups in the halogenated butyl rubber is 1-2.2%.

[0013] In some embodiments, R1 is selected from: -OCH3, -OCH2CH3, -CH3, -CH2CH3, and R2 is -CH3 or -CH2CH3.

[0014] In some of the embodiments, the molar ratio of the halogen group, the hydroxy olefinic acid compound and the hydrogen-containing silane in the halogenated butyl rubber is 1:0.8-3:0.8-3, preferably 1:0.9-1.1:0.9-1.1.

[0015] The second aspect of the present invention is to provide a method for preparing the modified butyl rubber, comprising the following steps:

[0016] (1) reacting the halogenated butyl rubber and the hydroxy olefinic acid compound in an organic solvent under the action of an inorganic base to obtain an intermediate product;

[0017] (2) reacting the intermediate product with the hydrosilane in an organic solvent under the action of a platinum catalyst to obtain the modified butyl rubber.

[0018] In some embodiments, the organic solvent in step (1) is tetrahydrofuran.

[0019] In some embodiments, the inorganic base in step (1) is potassium carbonate.

[0020] In some of the embodiments, the molar ratio of the halogen group of the halogenated butyl rubber to potassium carbonate is 1:1-2.

[0021] In some embodiments, the reaction temperature of step (1) is 15°C to 35°C, and the reaction time is 10 hours to 20 hours.

[0022] In some embodiments, the platinum catalyst in step (2) is chloroplatinic acid or a Castel catalyst.

[0023] In some of the embodiments, the mass ratio of the hydrosilane to the platinum catalyst is 1:0.02% to 0.08%.

[0024] In some embodiments, the organic solvent in step (2) is toluene.

[0025] In some embodiments, the reaction in step (2) comprises: reacting at a temperature of 60°C to 90°C for 2 hours to 8 hours, then raising the temperature to 70°C to 100°C and continuing the reaction for 3 hours to 9 hours.

[0026] In some embodiments, the reaction in step (2) comprises: reacting at a temperature of 65°C to 75°C for 3 to 6 hours, then raising the temperature to 90°C to 100°C and continuing the reaction for 5 to 7 hours.

[0027] In some embodiments, the method for preparing the modified butyl rubber comprises the following steps:

[0028] The halogenated butyl rubber is dissolved in tetrahydrofuran, and the hydroxy olefinic acid compound and the inorganic base are added to the solution, stirred at 15°C to 35°C for 10 to 20 hours, the solid is removed and then the tetrahydrofuran is removed, the intermediate product is dissolved in toluene, the hydrosilane and the platinum catalyst are added, the temperature is raised to 60°C to 90°C, the reaction is carried out for 2 to 8 hours, and then the temperature is raised to 70°C to 100°C and the reaction is continued for 3 to 9 hours, and finally the temperature in the reactor is raised to 110°C to 130°C and the solvent is removed by vacuum to obtain the modified butyl rubber.

[0029] The third aspect of the present invention is to provide a self-repairing butyl hot melt adhesive for photovoltaic modules, wherein the raw materials for preparing the self-repairing butyl hot melt adhesive include the modified butyl rubber described in the present invention.

[0030] In some of the embodiments, the self-repairing butyl hot melt adhesive for photovoltaic modules is prepared from raw materials comprising the following components, in parts by weight:

[0031]

[0032]

[0033] In some of the embodiments, the self-repairing butyl hot melt adhesive for photovoltaic modules is prepared from raw materials comprising the following components, in parts by weight:

[0034]

[0035] In some of the embodiments, the self-repairing butyl hot melt adhesive for photovoltaic modules is prepared from raw materials comprising the following components, in parts by weight:

[0036]

[0037]

[0038] In some of the embodiments, the polyisobutylene is composed of two or three of low molecular weight polyisobutylene, medium molecular weight polyisobutylene and high molecular weight polyisobutylene; the viscosity average molecular weight of the low molecular weight polyisobutylene is 400 to 30,000, the viscosity average molecular weight of the medium molecular weight polyisobutylene is 30,000 to 100,000; and the viscosity average molecular weight of the high molecular weight polyisobutylene is 100,000 to 2,000,000.

[0039] In some of the embodiments, the polyisobutylene is composed of medium molecular weight polyisobutylene and high molecular weight polyisobutylene; the viscosity average molecular weight of the medium molecular weight polyisobutylene is 60,000 to 95,000; and the viscosity average molecular weight of the high molecular weight polyisobutylene is 200,000 to 500,000.

[0040] In some of the embodiments, the polyisobutylene is composed of medium molecular weight polyisobutylene and high molecular weight polyisobutylene in a mass ratio of 1:0.5-1.5.

[0041] In some embodiments, the metal salt is an iron salt and / or a zinc salt.

[0042] In some embodiments, the metal salt is zinc chloride and / or ferric chloride.

[0043] In some embodiments, the plasticizer is a combination of one or more of polybutene, phthalate, dioctyl adipate and diisooctyl adipate.

[0044] In some embodiments, the tackifying resin is selected from one or more combinations of C5 petroleum resin, C9 petroleum resin, terpene resin, styrene-grafted terpene resin, polyterpene resin, natural resin and rosin resin.

[0045] In some embodiments, the water absorbent is selected from one or more combinations of calcium oxide, molecular sieves, calcium sulfate, anhydrous calcium chloride, anhydrous magnesium sulfate, and activated alumina.

[0046] In some embodiments, the inorganic filler is selected from one or more combinations of mica powder, silica powder, kaolin, calcium carbonate, talc, kaolin, clay and diatomaceous earth.

[0047] In some embodiments, the reinforcing agent is selected from one or a combination of carbon black and fumed silica.

[0048] In some embodiments, the antioxidant is selected from pentaerythritol tetrakis[2-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,6-di-tert-butyl-4-methylphenol, tris[2.4-di-tert-butylphenyl]phosphite, 2-methyl-4,6-dinonylphenol, 2,6-di-tert-butyl-α-methoxy-p-cresol, 2,4,6-tri-tert-butylphenol and a combination of one or more of 2,2,4-trimethyl-1,2-dihydroquinoline polymers.

[0049] In some embodiments, the light stabilizer is selected from one or more combinations of hindered amine light stabilizers.

[0050] In some embodiments, the light stabilizer is selected from 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole and / or 2-[2-hydroxy-5-tert-octylphenyl)benzotriazole.

[0051] A fourth aspect of the present invention is to provide a method for preparing a self-repairing butyl hot melt adhesive for photovoltaic modules, comprising the following steps:

[0052] At 110° C. to 160° C., the modified butyl rubber, polyisobutylene, plasticizer, tackifying resin and antioxidant are added to a kneader in sequence, and mixed under vacuum protection for 20 minutes to 130 minutes; then the inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt are added in sequence, and mixed under vacuum protection for 60 minutes to 180 minutes to obtain the self-healing butyl hot melt adhesive for photovoltaic modules.

[0053] In some embodiments, the method for preparing the self-repairing butyl hot melt adhesive for photovoltaic modules comprises the following steps:

[0054] At 140° C. to 160° C., the modified butyl rubber, polyisobutylene, plasticizer, tackifying resin and antioxidant are added to a kneader in sequence, and mixed under vacuum protection for 20 minutes to 40 minutes; then the inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt are added in sequence, and mixed under vacuum protection for 100 minutes to 150 minutes to obtain the self-repairing butyl hot melt adhesive for photovoltaic modules.

[0055] The present invention has the following beneficial effects:

[0056] The present invention modifies halogenated butyl rubber with hydroxy olefinic acid compounds and hydrogen-containing silane to obtain a modified butyl rubber having a siloxane group and a carboxyl group, and prepares the modified butyl rubber with components such as polyisobutylene and metal salts through appropriate formulas to form a reactive butyl hot melt adhesive with self-repairing properties. In the butyl hot melt adhesive system, the siloxane group is used for the dealcoholization reaction of the butyl hot melt adhesive system after the adhesive is applied to form a first layer of chemical cross-linking network, and on the other hand, it can improve the adhesion of the butyl hot melt adhesive to the glass, and the carboxyl group forms a second layer of cross-linking network with the metal salt through coordination, which enhances the mechanical properties of the material and also gives the butyl hot melt adhesive good self-repairing properties. Under the coordinated cooperation of each component, the butyl hot melt adhesive of the present invention has good adhesion to the glass interface, high strength, good mechanical properties, high water vapor barrier rate, and excellent self-repairing properties, and can be used in the field of photovoltaic modules. In addition, the electrostatic interaction in the system will reversibly dissociate at a higher temperature, and will not affect the processing and construction performance of the butyl hot melt adhesive. DETAILED DESCRIPTION

[0057] In order to facilitate the understanding of the present invention, the present invention will be described more fully below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0058] The experimental methods in the following examples without specifying specific conditions are usually carried out under conventional conditions or under conditions recommended by the manufacturers. The raw materials and various chemical reagents used in the examples are all commercially available products.

[0059] Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used in the present invention includes any and all combinations of one or more of the related listed items.

[0060] In addition, as used in the present invention, the term "or" is an inclusive "or" symbol and is equivalent to the term "and / or", unless the context clearly dictates otherwise. The term "based on" is not exclusive and allows for being based on other factors not described, unless the context clearly dictates otherwise. In addition, throughout the specification, the meanings of "a", "an", and "the" include plural referents. The meaning of "in..." includes "in..." and "on...".

[0061] The present invention is further described in detail below with reference to specific embodiments.

[0062] In the following embodiments, the normal temperature or room temperature refers to an indoor temperature of 20°C-30°C.

[0063] Example 1

[0064] 300g of brominated butyl rubber (raw rubber Mooney viscosity ML 1+8 =33, bromine content 1.9wt%, bromine molar amount 0.071mol, commercially available) is dissolved in 2L tetrahydrofuran, and then 13.3g HO(CH2)7CH=CHCOOH (0.071mol, commercially available) and 9.8g potassium carbonate (0.071mol, commercially available) are added to the solution, and after stirring at room temperature for 12 hours, the solid is filtered and then the tetrahydrofuran is removed by rotary evaporation. The resulting product is dissolved in 300mL toluene, and 8.7g HSi(OCH3)3 (0.071mol, commercially available) and 4.4mg chloroplatinic acid (the mass is 0.05% of the mass of hydrogen-containing silane, commercially available) are added, the temperature is raised to 70°C, the reaction is continued for 6 hours, and then the temperature is raised to 100°C for continued reaction for 7 hours, and finally the temperature in the reactor is raised to 110°C and the solvent is removed by vacuum to obtain the modified butyl rubber.

[0065] At 150°C, the modified butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant shown in Table 1 were added to the kneader in sequence, and blended for 30 minutes under -0.1 MPa vacuum protection; then the inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt shown in Table 1 were added in sequence, and the mixture was fully mixed for 120 minutes under -0.1 MPa vacuum protection to obtain a self-healing butyl hot melt adhesive for photovoltaic modules.

[0066] Table 1

[0067]

[0068]

[0069] Example 2

[0070] 300g of chlorinated butyl rubber (raw rubber Mooney viscosity ML 1+8=38, chlorine content 1.26wt%, chlorine molar amount 0.1mol, commercially available) is dissolved in 2L tetrahydrofuran, and then 18.6g HO(CH2)7CH=CHCOOH (0.1mol, commercially available) and 13.8g (0.1mol, commercially available) potassium carbonate are added to the solution, and after stirring at room temperature for 18 hours, the solid is filtered and then the tetrahydrofuran is removed by rotary evaporation. The resulting product is dissolved in 300mL toluene, and 16.4g HSi(OCH2CH3)3 (0.1mol, commercially available) and 8.5mg (the mass is 0.05% of the mass of hydrogen-containing silane, commercially available) chloroplatinic acid are added, the temperature is raised to 70°C, the reaction is carried out for 3 hours, and then the temperature is raised to 100°C for further reaction for 7 hours. Finally, the temperature in the reactor is raised to 110°C and the solvent is removed by vacuum to obtain the modified butyl rubber.

[0071] At 170°C, modified butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant were added to the kneader in sequence according to Table 2, and blended for 30 minutes under -0.1 MPa vacuum protection; then inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt were added in sequence, and the mixture was fully mixed for 120 minutes under -0.1 MPa vacuum protection to obtain a self-healing butyl hot melt adhesive for photovoltaic modules.

[0072] Table 2

[0073]

[0074]

[0075] Example 3

[0076] 300g of brominated butyl rubber (raw rubber Mooney viscosity ML 1+8 =33, bromine content 1.9wt%, bromine molar amount 0.071mol, commercially available) was dissolved in 2L of tetrahydrofuran, and then 8.2g HO(CH2)2CH=CHCOOH (0.071mol, commercially available) and 9.8g (0.071mol, commercially available) potassium carbonate were added to the solution, and stirred at room temperature for 18 hours. The tetrahydrofuran was removed by rotary evaporation after filtering the solid, and the resulting product was dissolved in 300mL of toluene. 11.6g HSi(OCH2CH3)3 (0.071mol, commercially available) and 5.8mg Custer catalyst (the mass is 0.05% of the mass of hydrogen-containing silane, commercially available) were added, the temperature was raised to 70°C, the reaction was continued for 3 hours, and then the temperature was raised to 90°C for further reaction for 5 hours. Finally, the temperature in the reactor was raised to 110°C and the solvent was removed by vacuum to obtain the modified butyl rubber.

[0077] At 160°C, the modified butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant were added to the kneader in sequence according to Table 3, and blended for 60 minutes under -0.1 MPa vacuum protection; then the inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt were added in sequence, and the mixture was fully mixed for 120 minutes under -0.1 MPa vacuum protection to obtain a self-healing butyl hot melt adhesive for photovoltaic modules.

[0078] Table 3

[0079]

[0080] Example 4

[0081] 300g of brominated butyl rubber (raw rubber Mooney viscosity ML 1+8 =33, bromine content 1.9wt%, bromine molar amount 0.071mol, commercially available) is dissolved in 2L tetrahydrofuran, and then 13.3g HO(CH2)7CH=CHCOOH (0.071mol, commercially available) and 9.8g potassium carbonate (0.071mol, commercially available) are added to the solution, and after stirring at room temperature for 18 hours, the solid is filtered and then the tetrahydrofuran is removed by rotary evaporation. The resulting product is dissolved in 300mL toluene, and 7.6g HSi(CH3)(OCH3)2 (0.071mol, commercially available) and 3.8mg Custer catalyst (the mass is 0.05% of the mass of hydrogen-containing silane, commercially available) are added, the temperature is raised to 70°C, the reaction is carried out for 4 hours, and then the temperature is raised to 90°C for further reaction for 5 hours. Finally, the temperature in the reactor is raised to 110°C and the solvent is removed by vacuum to obtain the modified butyl rubber.

[0082] At 160°C, modified butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant were added to the kneader in sequence according to Table 4, and blended for 45 minutes under -0.1 MPa vacuum protection; then inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt were added in sequence, and the mixture was fully mixed for 120 minutes under -0.1 MPa vacuum protection to obtain a self-healing butyl hot melt adhesive for photovoltaic modules.

[0083] Table 4

[0084]

[0085] Example 5

[0086] 300g of brominated butyl rubber (raw rubber Mooney viscosity ML 1+8=33, bromine content 1.9wt%, bromine molar amount 0.071mol, commercially available) is dissolved in 2L tetrahydrofuran, and then 8.2g HO(CH2)2CH=CHCOOH (0.071mol, commercially available) and 9.8g potassium carbonate (0.071mol, commercially available) are added to the solution, and after stirring at room temperature for 18 hours, the solid is filtered and then the tetrahydrofuran is removed by rotary evaporation. The resulting product is dissolved in 300mL toluene, and 9.6g HSi(CH3)(OCH2CH3)2 (0.071mol, commercially available) and 4.8mg Custer catalyst (the mass is 0.05% of the mass of hydrogen-containing silane) are added, the temperature is raised to 70°C, the reaction is carried out for 5 hours, and then the temperature is raised to 90°C for further reaction for 5 hours. Finally, the temperature in the reactor is raised to 110°C and the solvent is removed by vacuum to obtain the modified butyl rubber.

[0087] At 160°C, the modified butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant were added to the kneader in sequence according to Table 5, and blended for 45 minutes under -0.1 MPa vacuum protection; then the inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt were added in sequence, and the mixture was fully mixed for 120 minutes under -0.1 MPa vacuum protection to obtain a self-healing butyl hot melt adhesive for photovoltaic modules.

[0088] Table 5

[0089]

[0090]

[0091] Comparative Example 1

[0092] The difference between this comparative example and Example 1 is that no metal salt is added.

[0093] 300g of brominated butyl rubber (raw rubber Mooney viscosity ML 1+8 =33, bromine content 1.9wt%, bromine molar amount 0.071mol) is dissolved in 2L tetrahydrofuran, and then 13.3g HO(CH2)7CH=CHCOOH (0.071mol, commercially available) and 9.8g potassium carbonate (0.071mol, commercially available) are added to the solution. After stirring at room temperature for 12 hours, the solid is filtered and then the tetrahydrofuran is removed by rotary evaporation. The resulting product is dissolved in 300mL toluene, and 8.7g HSi(OCH3)3 (0.071mol, commercially available) and 4.4mg chloroplatinic acid (the mass is 0.05% of the mass of hydrogen-containing silane) are added. The temperature is raised to 70°C and the reaction is continued for 6 hours, then the temperature is raised to 100°C and the reaction is continued for 7 hours. Finally, the temperature in the reactor is raised to 110°C and the solvent is removed by vacuum to obtain the modified butyl rubber.

[0094] At 150°C, add butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant to the kneader in sequence according to Table 6, and blend for 30 minutes under -0.1 MPa vacuum protection; then add inorganic filler, reinforcing agent, light stabilizer and water absorbent in sequence, and mix thoroughly for 120 minutes under -0.1 MPa vacuum protection to obtain butyl hot melt adhesive for photovoltaic modules.

[0095] Table 6

[0096]

[0097]

[0098] Comparative Example 2

[0099] The difference between this comparative example and Example 1 is that the brominated butyl rubber is not modified.

[0100] At 150°C, add bromobutyl rubber (raw rubber Mooney viscosity ML 1+8 =33, bromine content 1.9wt%, commercially available), polyisobutylene mixture, plasticizer, tackifying resin and antioxidant, blended under vacuum protection for 30 minutes; then inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt were added in sequence, and fully mixed under -0.1MPa vacuum protection for 120 minutes to obtain butyl hot melt adhesive for photovoltaic modules.

[0101] Table 7

[0102]

[0103]

[0104] Comparative Example 3

[0105] The difference between this comparative example and Example 1 is that no hydroxy olefinic acid compound is added during the preparation of the modified butyl rubber.

[0106] 300g of brominated butyl rubber (raw rubber Mooney viscosity ML 1+8 =33, bromine content 1.9wt%, bromine molar amount 0.071mol, commercially available) was dissolved in 300mL toluene, 8.7g HSi(OCH3)3 (0.071mol, commercially available) and 4.4mg chloroplatinic acid (the mass is 0.05% of the mass of hydrogen-containing silane, commercially available) were added, the temperature was raised to 70°C, the reaction was continued for 6 hours, and then the temperature was raised to 100°C for further reaction for 7 hours, and finally the temperature in the reactor was raised to 110°C and the solvent was removed by vacuum to obtain the modified butyl rubber.

[0107] At 150°C, add modified butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant to the kneader in sequence according to Table 8, and blend for 30 minutes under -0.1 MPa vacuum protection; then add inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt in sequence, and mix thoroughly for 120 minutes under -0.1 MPa vacuum protection to obtain butyl hot melt adhesive for photovoltaic modules.

[0108] Table 8

[0109]

[0110] Comparative Example 4

[0111] The difference between this comparative example and Example 1 is that no hydrogen-containing silane and platinum catalyst are added during the preparation of the modified butyl rubber.

[0112] 300g of brominated butyl rubber (raw rubber Mooney viscosity ML 1+8 =33, bromine content 1.9wt%, bromine molar amount 0.071mol, commercially available) was dissolved in 2L of tetrahydrofuran, and then 13.3g of HO(CH2)7CH=CHCOOH (0.071mol, commercially available) and 9.8g of potassium carbonate (0.071mol, commercially available) were added to the solution. After stirring at room temperature for 12 hours, the solid was filtered and the tetrahydrofuran was removed to obtain the modified butyl rubber.

[0113] At 150°C, add modified butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant to the kneader in sequence according to Table 9, and blend for 30 minutes under vacuum protection; then add inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt in sequence, and mix thoroughly for 120 minutes under vacuum protection to obtain a self-healing butyl hot melt adhesive for photovoltaic modules.

[0114] Table 9

[0115]

[0116] Comparative Example 5

[0117] The difference between this comparative example and Example 1 is that the hydroxy olefinic acid compound is replaced by H2NCOCH=CHCOOH during the preparation of the modified butyl rubber.

[0118] 300g of brominated butyl rubber (raw rubber Mooney viscosity ML 1+8=33, bromine content 1.9wt%, bromine molar amount 0.071mol, commercially available) is dissolved in 2L tetrahydrofuran, and then 8.2g H2NCOCH=CHCOOH (0.071mol, commercially available) and 9.8g potassium carbonate (0.071mol, commercially available) are added to the solution, and after stirring at room temperature for 12 hours, the solid is filtered and then the tetrahydrofuran is removed by rotary evaporation. The resulting product is dissolved in 300mL toluene, and 8.7g HSi(OCH3)3 (0.071mol, commercially available) and 4.4mg chloroplatinic acid (the mass is 0.05% of the mass of hydrogen-containing silane, commercially available) are added, the temperature is raised to 70°C, the reaction is continued for 6 hours, and then the temperature is raised to 100°C for continued reaction for 7 hours, and finally the temperature in the reactor is raised to 110°C and the solvent is removed by vacuum to obtain the modified butyl rubber.

[0119] At 150°C, the modified butyl rubber, polyisobutylene mixture, plasticizer, tackifying resin and antioxidant shown in Table 10 were added to the kneader in sequence, and blended for 30 minutes under -0.1 MPa vacuum protection; then the inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt shown in Table 10 were added in sequence, and the mixture was fully mixed for 120 minutes under -0.1 MPa vacuum protection to obtain a self-healing butyl hot melt adhesive for photovoltaic modules.

[0120] Table 10

[0121]

[0122]

[0123] The butyl hot melt adhesives prepared in Examples 1 to 5 and Comparative Examples 1 to 5 were subjected to the performance tests shown in Table 11. The performance test methods of the samples in Table 11 are as follows:

[0124] 1. Double glass shear strength: Test the shear strength according to the method specified in GB / T 7124-2008;

[0125] 2. Self-healing test: Reassemble the fractured parts of the samples that have completed the shear strength test, place them at room temperature for 7 days, and then perform the double-glass shear strength test according to GB / T 7124-2008.

[0126] 3. 38℃, 90%RH water vapor transmission rate: Test according to GB / T 26253-2010. Put the glue on the release paper, heat it to the appropriate temperature, and then press it into a sheet with a thickness of (1±0.1)mm, a length of not less than 120mm, and a width of not less than 120mm. Take a circular test piece with a diameter of not less than 100mm for testing.

[0127] The results are shown in Table 11.

[0128] As shown in Table 11, no coordinated metal salt is added to the butyl hot melt adhesive of Comparative Example 1, no butyl rubber is modified in Comparative Example 2, and no hydroxy olefinic acid compounds are introduced into the modified butyl rubber of Comparative Example 3. The strength of the butyl hot melt adhesives prepared in Comparative Examples 1 to 3 is lower than that of Examples 1 to 5, and none of them have self-healing properties, which is manifested in that the shear strength of the fracture spliced ​​samples is greatly reduced, and Comparative Examples 1 to 3 have no physical cross-linking network, and the water vapor permeability is higher than that of Examples 1 to 5. Hydroxy olefinic acid compounds and siloxanes are introduced into the butyl hot melt adhesives prepared in Examples 1 to 5 at the same time. After the fracture splicing, most of the shear strength of the samples is restored, and the self-healing of the butyl hot melt adhesive at room temperature is achieved. Only hydroxy olefinic acid compounds are introduced into the butyl hot melt adhesive prepared in Comparative Example 4, and no siloxane is introduced. Although it also has a certain self-healing ability, it does not form a good chemical bond with the substrate, and its strength is much lower than that of Examples 1 to 5. The lack of a chemical cross-linking network also makes its water vapor permeability higher than that of Examples 1 to 5.

[0129] Comparative Example 5 is modified using amide olefinic acid compounds. Since they do not react with halogenated butyl rubber, they cannot be grafted onto the butyl rubber polymer chain, which will reduce the crosslinking density and self-healing properties of the material. The butyl hot melt adhesive prepared in Comparative Example 5 shows shear strength and fracture splicing sample shear strength that are much lower than those of Examples 1 to 5, and the presence of small molecules will affect the density of the material, resulting in its water vapor permeability being much higher than that of Examples 1 to 5.

[0130] Table 11 Summary of butyl hot melt adhesive properties in the examples

[0131]

[0132] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A modified butyl rubber, characterized in that: It is obtained by reacting halogenated butyl rubber with hydroxy olefinic acid compounds and hydrogen-containing silane in sequence; The structural formula of the hydroxy olefinic acid compound is HO(CH2) m CH=CHCOOH, wherein m is selected from: 2, 3, 4, 5, 6, 7, 8; The structural formula of the hydrogen-containing silane is HSi(R1)(OR2)2, wherein R1 is selected from: C1-C6 alkoxy, C1-C6 alkyl, and R2 is selected from: C1-C6 alkyl.

2. The modified butyl rubber according to claim 1, characterized in that The halogenated butyl rubber is brominated butyl rubber and / or chlorinated butyl rubber; and / or, The raw Mooney viscosity ML of the halogenated butyl rubber 1+8 is 27 to 50, preferably 30 to 40; and / or, The mass content of halogen groups in the halogenated butyl rubber is 1 to 2.2%.

3. The modified butyl rubber according to claim 1, characterized in that R1 is selected from: -OCH3, -OCH2CH3, -CH3, -CH2CH3, and R2 is -CH3 or -CH2CH3.

4. The modified butyl rubber according to any one of claims 1 to 3, characterized in that: The molar ratio of the halogen group, the hydroxy olefinic acid compound and the hydrogen-containing silane in the halogenated butyl rubber is 1:0.8-3:0.8-3, preferably 1:0.9-1.1:0.9-1.

1.

5. A method for preparing the modified butyl rubber according to any one of claims 1 to 4, characterized in that: The steps include: (1) reacting the halogenated butyl rubber and the hydroxy olefinic acid compound in an organic solvent under the action of an inorganic base to obtain an intermediate product; (2) reacting the intermediate product with the hydrosilane in an organic solvent under the action of a platinum catalyst to obtain the modified butyl rubber.

6. The method for preparing modified butyl rubber according to claim 5, characterized in that: The organic solvent in step (1) is tetrahydrofuran; and / or, The inorganic base in step (1) is potassium carbonate; and / or, The reaction temperature in step (1) is 15°C to 35°C, and the reaction time is 10 hours to 20 hours; and / or, The platinum catalyst in step (2) is chloroplatinic acid or a Custer catalyst; and / or, The mass ratio of the hydrosilane to the platinum catalyst is 1:0.02% to 0.08%; and / or, The organic solvent in step (2) is toluene; and / or, The reaction in step (2) comprises: reacting at a temperature of 60° C. to 90° C. for 2 to 8 hours, then raising the temperature to 70° C. to 100° C. and continuing the reaction for 3 to 9 hours; Preferably, the molar ratio of the halogen group of the halogenated butyl rubber to potassium carbonate is 1:1-2.

7. A self-repairing butyl hot melt adhesive for photovoltaic modules, characterized in that: The raw materials for its preparation contain the modified butyl rubber described in any one of claims 1 to 4.

8. The self-repairing butyl hot melt adhesive for photovoltaic modules according to claim 7, characterized in that: The composition is prepared from the following raw materials in parts by weight: 1 to 40 parts of the modified butyl rubber according to any one of claims 1 to 4, Preferably, the self-repairing butyl hot melt adhesive for photovoltaic modules is prepared from raw materials comprising the following components in parts by weight:

9. The self-repairing butyl hot melt adhesive for photovoltaic modules according to claim 8, characterized in that: The polyisobutylene is composed of two or three of low molecular weight polyisobutylene, medium molecular weight polyisobutylene and high molecular weight polyisobutylene, the viscosity average molecular weight of the low molecular weight polyisobutylene is 400-30,000, the viscosity average molecular weight of the medium molecular weight polyisobutylene is 30,000-100,000, and the viscosity average molecular weight of the high molecular weight polyisobutylene is 100,000-2,000,000; and / or, The metal salt is an iron salt and / or a zinc salt; and / or, The plasticizer is a combination of one or more of polybutene, phthalate, dioctyl adipate and diisooctyl adipate; and / or, The tackifying resin is selected from one or more combinations of C5 petroleum resin, C9 petroleum resin, terpene resin, styrene-grafted terpene resin, polyterpene resin and rosin resin; and / or, The water absorbing agent is selected from one or more combinations of calcium oxide, molecular sieves, calcium sulfate, anhydrous calcium chloride, anhydrous magnesium sulfate, and activated alumina; and / or, The inorganic filler is selected from one or more combinations of mica powder, silica powder, kaolin, calcium carbonate, talc, kaolin, clay and diatomaceous earth; and / or, The reinforcing agent is selected from one or a combination of carbon black and fumed silica; and / or, The antioxidant is selected from the group consisting of one or more combinations of pentaerythritol tetrakis[2-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,6-di-tert-butyl-4-methylphenol, tris[2,4-di-tert-butylphenyl]phosphite, 2-methyl-4,6-dinonylphenol, 2,6-di-tert-butyl-α-methoxy-p-cresol, 2,4,6-tri-tert-butylphenol and 2,2,4-trimethyl-1,2-dihydroquinoline polymer; and / or, The light stabilizer is selected from one or more combinations of hindered amine light stabilizers; Preferably, the polyisobutylene is composed of medium molecular weight polyisobutylene and high molecular weight polyisobutylene; the viscosity average molecular weight of the medium molecular weight polyisobutylene is 60,000 to 95,000; the viscosity average molecular weight of the high molecular weight polyisobutylene is 200,000 to 500,000; More preferably, the polyisobutylene is composed of medium molecular weight polyisobutylene and high molecular weight polyisobutylene in a mass ratio of 1:0.5-1.5; Preferably, the metal salt is zinc chloride and / or ferric chloride; Preferably, the light stabilizer is selected from 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole and / or 2-[2-hydroxy-5-tert-octylphenyl)benzotriazole.

10. A method for preparing the self-repairing butyl hot melt adhesive for photovoltaic modules according to claim 8 or 9, characterized in that: The following steps are involved: At 110° C. to 160° C., the modified butyl rubber, polyisobutylene, plasticizer, tackifying resin and antioxidant are added to a kneader in sequence, and mixed under vacuum protection for 20 minutes to 130 minutes; then the inorganic filler, reinforcing agent, water absorbent, light stabilizer and metal salt are added in sequence, and mixed under vacuum protection for 60 minutes to 180 minutes to obtain the self-healing butyl hot melt adhesive for photovoltaic modules.

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