A high-transmittance, strong-bonding silane-modified sealant and preparation method thereof

Abstract

The present invention relates to a high-transmittance strong-bonding silane-modified sealant and a preparation method thereof, and belongs to the technical field of sealants. The high-transmittance strong-bonding silane-modified sealant comprises a silane-modified polyether resin, a reactive plasticizer, a water-removing agent, a highly active cross-linking agent, a color paste, modified silicon dioxide, a liquid ultraviolet absorber, and an environmentally friendly catalyst. The preparation method comprises vacuuming and stirring the silane-modified polyether resin, the reactive plasticizer, the liquid ultraviolet absorber, the color paste, and part of the water-removing agent, adding the modified silicon dioxide and stirring at high speed, adding the highly active cross-linking agent, the remaining water-removing agent, and the environmentally friendly catalyst and vacuuming and stirring at high speed to obtain the sealant. The sealant prepared by the present invention has good flexibility, excellent strength, good adhesion to the substrate, high light transmittance, and good yellowing resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of sealants, and relates to a high-transmittance, strong-bonding silane-modified sealant and a preparation method thereof. Background Art

[0002] Conventional silane-modified polyether sealants are mostly opaque paste-like adhesives with average strength, which limits their application in high-transparency occasions, such as high-end residential interior decoration, automobile transportation, window process equipment, colored crystal glass, and highly transparent crafts, which require sealants with high transmittance and good bonding strength. Therefore, a high-transmittance silane-modified polyether sealant with excellent comprehensive performance was developed, taking into account transparency, yellowing resistance and adhesion.

[0003] According to the related patents that have been published on highly transparent silane-modified polyether sealants, they all emphasize high transparency and high strength, but ignore the sealant's adhesion and yellowing resistance. Some sealants have high strength, but poor adhesion to the substrate and poor colloid flexibility; some sealants have good light transmittance at the beginning, but turn yellow after a while. Therefore, the problem to be solved by this patent is to prepare a silane-modified sealant with good colloid flexibility, excellent strength, good adhesion to the substrate, and good yellowing resistance.

[0004] Patent document with publication number CN113025253 A discloses a one-component silane-modified polyether sealant and its preparation method and application. The silane-modified polyether sealant includes a silane-modified polyether resin, a reinforcing resin, a polyether polyol plasticizer, a liquid rheological agent, a stabilizer, and a water scavenger. The invention uses a polyether amine and a bisphenol A epoxy resin for a ring-opening reaction, and then uses a trialkoxysilane and a hydroxyl group for end-capping to prepare a reinforcing resin. However, the cured product of the invention patent is very brittle and easily turns yellow. The adhesion and yellowing resistance of the sealant need to be further improved.

[0005] Patent document with publication number CN108504318 A discloses a silane-modified polyether elastic sealant with high transparency and high strength and a preparation method thereof. The silane-modified sealant includes a base polymer, a polypropylene glycol plasticizer, white carbon black, a cross-linking agent, a water scavenger, an ultraviolet absorber, a light stabilizer, an adhesion promoter, and a catalyst. The invention patent has high strength and an adhesion promoter is added, but it still faces the same problem that the sealant has problems with substrate adhesion and yellowing resistance.

[0006] Disadvantages of the existing technology: 1) The existing technology solutions all use non-reactive plasticizers, which have a strong odor and are not environmentally friendly, and have poor compatibility with resins; or dry glue occurs and has poor storage performance. 2) The existing technology has a high tensile strength and is easy to debond from the substrate and has poor adhesion. 3) The existing technology has poor yellowing resistance and is prone to yellowing over time. Summary of the invention

[0007] The purpose of the present invention is to provide a high-transmittance, strong-bonding silane-modified sealant and a preparation method thereof, so as to prepare an environmentally friendly, non-toxic, high-transmittance, good adhesion to substrates, excellent strength and yellowing resistance sealant.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] A high light transmittance and strong bonding silane modified sealant, characterized in that it comprises the following components in parts by weight:

[0010] 70-90 parts of silane modified polyether resin, 20-30 parts of reactive plasticizer, 1-3 parts of water remover, 4-6 parts of high activity cross-linking agent, 0.3-1.5 parts of color paste, 15-20 parts of modified silicon dioxide, 0.2-1 parts of liquid ultraviolet absorber and 0.5-2 parts of environmentally friendly catalyst.

[0011] As a preferred technical solution of the present invention, the functionality of the silane-modified polyether resin is n=3, the terminal group is methoxy or ethoxy, the main chain is polypropylene glycol, and the silane-modified polyether polymer containing polybutadiene or tetrahydrofuran chain segments has the following structural formula:

[0012]

[0013] The invention discloses a preparation method of the reactive plasticizer, comprising the following steps: stirring and mixing bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane and diethylenetriaminopropyltrialkoxysilane, adding a catalyst, heating and stirring to obtain the plasticizer.

[0014] As a preferred technical solution of the present invention, in the preparation of the reactive plasticizer, the molar ratio of the bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane to the diethylenetriaminopropyltrialkoxysilane is 1:2.

[0015] As a preferred technical solution of the present invention, in the preparation of the reactive plasticizer, the heating and stirring is stirring at a speed of 300-400 r / min and 50-60° C. for 1-2 hours; the catalyst is tetrabutylammonium fluoride, and the diethylenetriaminopropyltrialkoxysilane is the silane coupling agent NQ-62.

[0016] As a preferred technical solution of the present invention, in the preparation of the reactive plasticizer, the reaction equation of the reactive plasticizer is as follows:

[0017]

[0018] As a preferred technical solution of the present invention, the highly active cross-linking agent is an α-silane coupling agent, and the structural formula is as follows:

[0019] Wherein, OR is methoxy or ethoxy, and X is

[0020] As a preferred technical solution of the present invention, the environmentally friendly catalyst is an organic bismuth compound; the organic bismuth compound is one or more of CAT TA5600, CAT MR20 and CAT MR8.

[0021] As a preferred technical solution of the present invention, the liquid ultraviolet absorber is one or two of Lianlong UV-1130, UV-292, UV-400, UV384-2, UV-123, UV-400, and UV-1130; and the color paste is phthalocyanine blue paste.

[0022] The preparation of the modified silicon dioxide comprises the following steps:

[0023] Step S1: After mixing silica, anhydrous ethanol and a coupling agent, stirring at 35-40° C. and 300-400 r / min for 30-45 min, cooling to room temperature, centrifuging, and vacuum drying the solid to constant weight to obtain modified silica;

[0024] Step S2: After ultrasonically mixing the modified silica and tetrahydrofuran, glycidyl methacrylate, butadiene and oleic acid are added and stirred under a nitrogen atmosphere, an initiator is added and stirred at a temperature of 60-65° C. and a speed of 300-400 r / min for 5-6 hours. After cooling to room temperature, the mixture is centrifuged and the solid is dried at 70° C. and vacuum dried to constant weight to obtain modified silica.

[0025] As a preferred technical solution of the present invention, in step S1, the mass ratio of the silicon dioxide, anhydrous ethanol and coupling agent is 10-12:30-35:2.0-2.4; the coupling agent is γ-methacryloxypropyltrimethoxysilane.

[0026] As a preferred technical solution of the present invention, in step S2, the mass ratio of the modified silica, organic solvent, glycidyl methacrylate, butadiene, oleic acid and initiator is 12-15:55-60:16-18:8-9:2.2-2.5:1.2-1.4; the initiator is azobisisobutyronitrile.

[0027] As a preferred technical solution of the present invention, the dehydrating agent is one or more of hexamethyldisilazane, vinyltrimethoxysilane and vinyltriethoxysilane.

[0028] The invention discloses a method for preparing a high-transmittance and strong-bonding silane-modified sealant, the preparation method comprising the following steps:

[0029] Mix silane modified polyether resin, reactive plasticizer, ultraviolet absorber, color paste and 30-60% dehydrating agent, evacuate and stir at high speed for 5-10 minutes, add modified silicon dioxide and stir at high speed for 5-10 minutes, evacuate and continue stirring for 25-30 minutes, add high-activity crosslinking agent, remaining dehydrating agent and environmentally friendly catalyst and stir at high speed for 10-15 minutes to obtain the product.

[0030] As a preferred technical solution of the present invention, the sealant of the present invention can be applied to high-end interior decoration, automobile transportation, window equipment, colored glass, high-transparency handicrafts, etc.

[0031] Beneficial effects of the present invention:

[0032] The sealant prepared by the invention has good flexibility, excellent strength, good adhesion to substrates and good yellowing resistance. By chemically modifying silicon dioxide, using silicon dioxide as a particle core and a polymer layer of butadiene-oleic acid-glycidyl acrylate coated on the outer layer of the particle core, the flexibility of the sealant is improved, the surface of the sealant has hydrophobicity, and the adhesion of the interface between the sealant and the substrate is increased.

[0033] The sealant of the present invention does not contain inactive plasticizers, and adopts a coupling agent with a special structure to prepare a reactive plasticizer with a long chain structure, thereby improving the chemical affinity between the plasticizer and the polymer resin, and having better compatibility and stability, better yellowing resistance and higher bonding strength; adding a high-activity cross-linking agent, the reaction is more complete, and the deep curing is faster; adopting an organic bismuth catalyst to replace organic tin, the sealant is more environmentally friendly and healthy, and complies with the EU ROHS / REACH standards; adding phthalocyanine blue slurry, the sealant has higher transparency and better yellowing resistance. DETAILED DESCRIPTION

[0034] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0035] Example 1

[0036] A high light transmittance strong bonding silane modified sealant comprises the following components in parts by weight:

[0037] 70 parts of silane-modified polyether resin, 20 parts of reactive plasticizer, 1 part of water remover, 4 parts of highly active cross-linking agent, 0.3 parts of phthalocyanine blue paste, 15 parts of modified silicon dioxide, 0.2 parts of ultraviolet absorber and 0.5 parts of environmentally friendly catalyst;

[0038] Among them, the environmentally friendly catalyst is CAT TA5600; the dehydrating agent is a mixture of hexamethyldisilazane and vinyltrimethoxysilane in a mass ratio of 1:2; and the liquid ultraviolet absorber is Lianlong UV-1130.

[0039] The preparation of the modified silicon dioxide comprises the following steps:

[0040] Step S1: After mixing silica, anhydrous ethanol and a coupling agent, stirring at 35° C. and 300 r / min for 30 min, cooling to room temperature, centrifuging, and vacuum drying the solid to constant weight to obtain modified silica;

[0041] Step S2: After ultrasonically mixing the modified silica and tetrahydrofuran, glycidyl methacrylate, butadiene and oleic acid are added and stirred under a nitrogen atmosphere, an initiator is added and stirred at 60° C. and 300 r / min for 5 h. After cooling to room temperature, the mixture is centrifuged and the solid is dried at 70° C. and vacuum dried to constant weight to obtain modified silica.

[0042] In step S1, the mass ratio of the silicon dioxide, anhydrous ethanol and the coupling agent is 10:30:2.0; the coupling agent is γ-methacryloxypropyltrimethoxysilane.

[0043] In step S2, the mass ratio of the modified silica, the organic solvent, glycidyl methacrylate, butadiene, oleic acid and the initiator is 12:55:16:8:2.2:1.2; and the initiator is azobisisobutyronitrile.

[0044] The functionality of the silane-modified polyether resin is n=3, the terminal group is methoxy, the main chain is polypropylene glycol, and the silane-modified polyether polymer containing a polybutadiene chain segment has the following structural formula:

[0045]

[0046] The preparation method of the reactive plasticizer comprises the following steps: stirring and mixing bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane and diethylenetriaminopropyltrialkoxysilane, adding a catalyst, heating and stirring, and obtaining the reactive plasticizer; wherein the molar ratio of the bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane to the diethylenetriaminopropyltrialkoxysilane is 1:2; the heating and stirring is stirring at a speed of 300 r / min and 50° C. for 1 hour; and the catalyst is a tetrabutylammonium fluoride catalyst.

[0047] The highly active cross-linking agent is an α-silane coupling agent, and the structural formula is as follows:

[0048] Wherein, OR is a methoxy group, and X is

[0049] The preparation method of the high-transmittance strong-bonding silane-modified sealant comprises the following steps:

[0050] Mix silane modified polyether resin, reactive plasticizer, liquid ultraviolet absorber, phthalocyanine blue slurry and 30% dewatering agent, evacuate and stir at high speed for 5-10 minutes, add modified silicon dioxide and stir at high speed for 5 minutes, evacuate and continue stirring for 25 minutes, add high-activity crosslinking agent, remaining dewatering agent and environmentally friendly catalyst and stir at high speed for 10 minutes to obtain the product.

[0051] Example 2

[0052] A high light transmittance strong bonding silane modified sealant comprises the following components in parts by weight:

[0053] 80 parts of silane-modified polyether resin, 25 parts of reactive plasticizer, 2 parts of water remover, 5 parts of highly active cross-linking agent, 0.8 parts of phthalocyanine blue paste, 17.5 parts of modified silicon dioxide, 0.5 parts of liquid ultraviolet absorber and 0.8 parts of environmentally friendly catalyst;

[0054] Among them, the environmentally friendly catalyst is CAT TA5600; the dehydrating agent is a mixture of hexamethyldisilazane and vinyltrimethoxysilane in a mass ratio of 1:2; and the liquid ultraviolet absorber is Lianlong UV-400.

[0055] The preparation of the modified silicon dioxide comprises the following steps:

[0056] Step S1: After mixing silica, anhydrous ethanol and a coupling agent, stirring at 38°C and 350 r / min for 37 min, cooling to room temperature, centrifuging, and vacuum drying the solid to constant weight to obtain modified silica;

[0057] Step S2: After ultrasonically mixing the modified silica and tetrahydrofuran, glycidyl methacrylate, butadiene and oleic acid are added and stirred under a nitrogen atmosphere, an initiator is added and stirred at 62.5°C and 350 r / min for 5.5 h. After cooling to room temperature, the mixture is centrifuged and the solid is dried at 70°C in a vacuum dryer until constant weight is obtained to obtain modified silica.

[0058] In step S1, the mass ratio of the silicon dioxide, anhydrous ethanol and the coupling agent is 11:33:2.2; the coupling agent is γ-methacryloxypropyltrimethoxysilane.

[0059] In step S2, the mass ratio of the modified silica, the organic solvent, glycidyl methacrylate, butadiene, oleic acid and the initiator is 13.5:58:17:8.5:2.4:1.34; and the initiator is azobisisobutyronitrile.

[0060] The functionality of the silane-modified polyether resin is n=3, the terminal group is methoxy, the main chain is polypropylene glycol, and the silane-modified polyether polymer containing a polybutadiene chain segment has the following structural formula:

[0061]

[0062] The preparation method of the reactive plasticizer comprises the following steps: stirring and mixing bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane and diethylenetriaminopropyltrialkoxysilane, adding a catalyst, heating and stirring, and obtaining the reactive plasticizer; wherein the molar ratio of the bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane to the diethylenetriaminopropyltrialkoxysilane is 1:2; the heating and stirring is performed at a speed of 350 r / min and 55° C. for 1.5 hours; and the catalyst is a tetrabutylammonium fluoride catalyst.

[0063] The highly active cross-linking agent is an α-silane coupling agent, and the structural formula is as follows:

[0064] Wherein, OR is a methoxy group, and X is

[0065] The preparation method of the high-transmittance strong-bonding silane-modified sealant comprises the following steps:

[0066] Silane modified polyether resin, reactive plasticizer, liquid ultraviolet absorber, phthalocyanine blue slurry and 45% dewatering agent are mixed, vacuumed and stirred at high speed for 8 minutes, modified silicon dioxide is added and stirred at high speed for 8 minutes, vacuumed and stirred for 28 minutes, high-activity cross-linking agent, remaining dewatering agent and environmentally friendly catalyst are added and stirred at high speed for 13 minutes to obtain the product.

[0067] Example 3

[0068] A high light transmittance strong bonding silane modified sealant comprises the following components in parts by weight:

[0069] 90 parts of silane-modified polyether resin, 30 parts of reactive plasticizer, 3 parts of dewatering agent, 6 parts of high-activity crosslinking agent, 1.5 parts of phthalocyanine blue paste, 20 parts of modified silicon dioxide, 1 part of ultraviolet absorber and 2 parts of environmentally friendly catalyst;

[0070] Among them, the environmentally friendly catalyst is CAT TA5600; the dehydrating agent is a mixture of hexamethyldisilazane and vinyltrimethoxysilane in a mass ratio of 1:2; and the liquid ultraviolet absorber is Lianlong UV-123.

[0071] The preparation of the modified silicon dioxide comprises the following steps:

[0072] Step S1: After mixing silica, anhydrous ethanol and a coupling agent, stirring at 40° C. and 400 r / min for 45 min, cooling to room temperature, centrifuging, and vacuum drying the solid to constant weight to obtain modified silica;

[0073] Step S2: After ultrasonically mixing the modified silica and tetrahydrofuran, glycidyl methacrylate, butadiene and oleic acid are added and stirred under a nitrogen atmosphere, an initiator is added and stirred at 65° C. and 400 r / min for 6 hours. After cooling to room temperature, the mixture is centrifuged and the solid is dried at 70° C. in a vacuum oven until constant weight is obtained to obtain modified silica.

[0074] In step S1, the mass ratio of the silicon dioxide, anhydrous ethanol and the coupling agent is 12:35:2.4; the coupling agent is γ-methacryloxypropyltrimethoxysilane.

[0075] In step S2, the mass ratio of the modified silica, the organic solvent, glycidyl methacrylate, butadiene, oleic acid and the initiator is 15:60:18:9:2.5:1.4; and the initiator is azobisisobutyronitrile.

[0076] The functionality of the silane-modified polyether resin is n=3, the terminal group is methoxy, the main chain is polypropylene glycol, and the silane-modified polyether polymer containing a tetrahydrofuran chain segment has the following structural formula:

[0077]

[0078] The preparation method of the reactive plasticizer comprises the following steps: stirring and mixing bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane and diethylenetriaminopropyltrialkoxysilane, adding a catalyst and heating and stirring to obtain the reactive plasticizer; wherein the molar ratio of the bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane to the diethylenetriaminopropyltrialkoxysilane is 1:2; the heating and stirring is stirring at a speed of 400 r / min and 60° C. for 2 hours; and the catalyst is a tetrabutylammonium fluoride catalyst.

[0079] The highly active cross-linking agent is an α-silane coupling agent, and the structural formula is as follows:

[0080] Wherein, OR is a methoxy group, and X is

[0081] The preparation method of the high-transmittance strong-bonding silane-modified sealant comprises the following steps:

[0082] The silane-modified polyether resin, reactive plasticizer, liquid ultraviolet absorber, phthalocyanine blue slurry and 60% dewatering agent are mixed, and the mixture is stirred evenly at high speed for 10 minutes under vacuum. After modified silicon dioxide is added and stirred at high speed for 10 minutes, the mixture is stirred evenly at high speed for 30 minutes under vacuum. After adding a highly active cross-linking agent, the remaining dewatering agent and an environmentally friendly catalyst, the mixture is stirred evenly at high speed for 15 minutes to obtain the product.

[0083] Example 4

[0084] A high light transmittance strong bonding silane modified sealant comprises the following components in parts by weight:

[0085] 90 parts of silane-modified polyether resin, 30 parts of reactive plasticizer, 3 parts of dewatering agent, 6 parts of high-activity crosslinking agent, 1.5 parts of phthalocyanine blue paste, 20 parts of modified silicon dioxide, 0.7 parts of ultraviolet absorber and 1 part of environmentally friendly catalyst;

[0086] Among them, the environmentally friendly catalyst is CAT TA5600; the dehydrating agent is a mixture of hexamethyldisilazane and vinyltrimethoxysilane in a mass ratio of 1:2; and the liquid ultraviolet absorber is Lianlong UV-400.

[0087] The preparation of the modified silicon dioxide comprises the following steps:

[0088] Step S1: After mixing silica, anhydrous ethanol and a coupling agent, stirring at 40° C. and 400 r / min for 45 min, cooling to room temperature, centrifuging, and vacuum drying the solid to constant weight to obtain modified silica;

[0089] Step S2: After ultrasonically mixing the modified silica and tetrahydrofuran, glycidyl methacrylate, butadiene and oleic acid are added and stirred under a nitrogen atmosphere, an initiator is added and stirred at 65° C. and 400 r / min for 6 hours. After cooling to room temperature, the mixture is centrifuged and the solid is dried at 70° C. in a vacuum oven until constant weight is obtained to obtain modified silica.

[0090] In step S1, the mass ratio of the silicon dioxide, anhydrous ethanol and the coupling agent is 12:35:2.4; the coupling agent is γ-methacryloxypropyltrimethoxysilane.

[0091] In step S2, the mass ratio of the modified silica, the organic solvent, glycidyl methacrylate, butadiene, oleic acid and the initiator is 15:60:18:9:2.5:1.4; and the initiator is azobisisobutyronitrile.

[0092] The functionality of the silane-modified polyether resin is n=3, the terminal group is methoxy, the main chain is polypropylene glycol, and the silane-modified polyether polymer containing a tetrahydrofuran chain segment has the following structural formula:

[0093]

[0094] The preparation method of the reactive plasticizer comprises the following steps: stirring and mixing bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane and diethylenetriaminopropyltrialkoxysilane, adding a catalyst and heating and stirring to obtain the reactive plasticizer; wherein the molar ratio of the bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane to the diethylenetriaminopropyltrialkoxysilane is 1:2; the heating and stirring is stirring at a speed of 400 r / min and 60° C. for 2 hours; and the catalyst is a tetrabutylammonium fluoride catalyst.

[0095] The highly active cross-linking agent is an α-silane coupling agent, and the structural formula is as follows:

[0096] Wherein, OR is ethoxy, X is

[0097] The preparation method of the high-transmittance and strong-bonding silane-modified sealant comprises the following steps: mixing a silane-modified polyether resin, a reactive plasticizer, a liquid ultraviolet absorber, a phthalocyanine blue slurry and a 60% dewatering agent, vacuuming and stirring evenly at high speed for 10 minutes, adding modified silicon dioxide and stirring at high speed for 10 minutes, vacuuming and stirring continuously for 30 minutes, adding a high-activity cross-linking agent, the remaining dewatering agent and an environmentally friendly catalyst and stirring evenly at high speed for 15 minutes to obtain the sealant.

[0098] Comparative Example 1

[0099] Compared with Example 2, Comparative Example 1 is different in that bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane replaces the reactive plasticizer, and the other components, preparation steps and parameters are the same.

[0100] Comparative Example 2

[0101] Compared with Example 2, Comparative Example 2 is different in that butadiene is not used, and the other components, preparation steps and parameters are the same.

[0102] Comparative Example 3

[0103] Compared with Example 2, Comparative Example 3 is different in that oleic acid is not used, and the other components, preparation steps and parameters are the same.

[0104] Comparative Example 4

[0105] Compared with Example 2, Comparative Example 4 is different in that glycidyl methacrylate is not used, and the other components, preparation steps and parameters are the same.

[0106] The sealants prepared in Examples 1-4 and Comparative Examples 1-4 were subjected to the following performance tests, respectively. The test results are shown in Tables 1 and 2.

[0107] 1. Surface drying time: Test according to GB / T 13477.5-2003. Under the conditions of (23±2)℃ and (50±10)%RH, squeeze the adhesive strip onto a clean glass plate. Touch the adhesive surface with your finger every 1 minute. The time until it is no longer sticky is the surface drying time.

[0108] 2. Tensile strength and elongation at break are tested in accordance with GB / T 528-2009.

[0109] 3. The light transmittance is tested in accordance with GB / T 2410-2008;

[0110] 4. Yellowing resistance test: The test is carried out by accelerating yellowing at high temperature (the sealant that has been cured at room temperature for 7 days is placed in an oven at 120°C for 30 days, and its yellowing degree is observed. The yellowing degree is indicated by a yellowing scale of 0-6, and the higher the grade, the more serious the yellowing degree).

[0111] 5. Test of substrate adhesion: stick an anti-adhesive tape on one side of the substrate surface, apply high-transmittance and strong-adhesive silane-modified sealant on the surface of different substrates, and pull the sealant from the anti-adhesive tape after it is completely cured for 5 days, and peel it off at 90° at the bonding point to determine the type of bond surface damage and thus determine the bonding performance. The substrates are wood, stainless steel, aluminum alloy and PVC, and the thickness of the coating is 1mm.

[0112] Table 1 Test results

[0113]

[0114] It can be seen from the test results in Table 1 that, compared with Comparative Examples 1-4, the sealants prepared in Examples 1-4 of the present invention have good flexibility, excellent strength, high light transmittance, and good yellowing resistance.

[0115] Table 2 Test results

[0116] wood Stainless steel Aluminum Alloy PVC Example 1 Cohesive failure Cohesive failure Cohesive failure Cohesive failure Example 2 Cohesive failure Cohesive failure Cohesive failure Cohesive failure Example 3 Cohesive failure 95% cohesive failure Cohesive failure 90% cohesive failure Example 4 Cohesive failure 97% cohesive failure Cohesive failure 96% cohesive failure Comparative Example 1 75% cohesive failure 60% cohesive failure 65% cohesive failure 40% cohesive failure Comparative Example 2 91% cohesive failure 80% cohesive failure 85% cohesive failure 73% cohesive failure Comparative Example 3 86% cohesive failure 84% cohesive failure 71% cohesive failure 59% cohesive failure Comparative Example 4 80% cohesive failure 73% cohesive failure 74% cohesive failure 52% cohesive failure

[0117] From the test results in Table 2, it can be seen that compared with Comparative Examples 1-4, the sealant prepared in Examples 1-4 has excellent adhesion to different substrates such as wood, stainless steel, aluminum alloy, and PVC.

[0118] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high light transmittance and strong bonding silane modified sealant, characterized in that: The components include the following by weight: Silane modified polyether resin 70-90 parts, reactive plasticizer 20-30 parts, dewatering agent 1-3 parts, high activity crosslinking agent 4-6 parts, color paste 0.3-1.5 parts, nano-enhancer 15-20 parts, liquid ultraviolet absorber 0.2-1 parts and environmentally friendly catalyst 0.5-2 parts; The preparation method of the reactive plasticizer comprises the following steps: stirring and mixing bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane and diethylenetriaminopropyltrialkoxysilane, adding a catalyst, heating and stirring, and obtaining the plasticizer; The heating and stirring is stirring at a speed of 300-400 r / min and 50-60° C. for 1-2 hours; the catalyst is tetrabutylammonium fluoride; the diethylenetriaminopropyltrialkoxysilane is a silane coupling agent NQ-62; The nano-enhancer is modified silicon dioxide; the preparation of the modified silicon dioxide comprises: Step S1: After mixing silica, anhydrous ethanol and a coupling agent, stirring at 35-40° C. and 300-400 r / min for 30-45 min, cooling to room temperature, centrifuging, and vacuum drying the solid to constant weight to obtain modified silica; Step S2: After ultrasonically mixing the modified silica and tetrahydrofuran, glycidyl methacrylate, butadiene and oleic acid are added and stirred under a nitrogen atmosphere, an initiator is added and stirred at a temperature of 60-65° C. and a speed of 300-400 r / min for 5-6 hours. After cooling to room temperature, the mixture is centrifuged and the solid is dried at 70° C. and vacuum dried to constant weight to obtain modified silica.

2. The high light transmittance and strong bonding silane modified sealant according to claim 1, characterized in that: The functionality of the silane-modified polyether resin is n=3, the terminal group is methoxy or ethoxy, the main chain is polypropylene glycol, and the silane-modified polyether polymer containing polybutadiene or tetrahydrofuran chain segments has the following structural formula: 。 3. The high light transmittance and strong bonding silane modified sealant according to claim 1, characterized in that: In the preparation of the reactive plasticizer, the molar ratio of the bis(3-glycidyl epoxypropyl)-tetramethyldisiloxane to the diethylenetriaminopropyltrialkoxysilane is 1:

2.

4. The high light transmittance and strong bonding silane modified sealant according to claim 1, characterized in that: The highly active cross-linking agent is an α-silane coupling agent, and the structural formula is as follows: , wherein OR is methoxy or ethoxy, and X is , , , or .

5. The high light transmittance and strong bonding silane modified sealant according to claim 1, characterized in that: The environmentally friendly catalyst is an organic bismuth compound; the organic bismuth compound is one or more of CAT TA5600, CATMR20 and CATMR8; the liquid ultraviolet absorber is one or two of Lianlong UV-1130, UV-292, UV-400, UV384-2, and UV-123; the color paste is phthalocyanine blue paste; the dehydrating agent is one or more of hexamethyldisilazane, vinyltrimethoxysilane and vinyltriethoxysilane.

6. The high light transmittance and strong bonding silane modified sealant according to claim 1, characterized in that: In step S1, the mass ratio of the silica, anhydrous ethanol and coupling agent is 10-12:30-35:2.0-2.4; the coupling agent is γ-methacryloxypropyltrimethoxysilane; in step S2, the mass ratio of the modified silica, organic solvent, glycidyl methacrylate, butadiene, oleic acid and initiator is 12-15:55-60:16-18:8-9:2.2-2.5:1.2-1.4; the initiator is azobisisobutyronitrile.

7. A method for preparing a high-transmittance, strong-bonding silane-modified sealant according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: Mix the silane modified polyether resin, reactive plasticizer, liquid UV absorber, color paste and 30-60% dehydrating agent, evacuate and stir at high speed for 5-10 minutes, add modified silicon dioxide and stir at high speed for 5-10 minutes, evacuate and continue stirring for 25-30 minutes, add high activity cross-linking agent, remaining dehydrating agent and environmentally friendly catalyst and stir at high speed for 10-15 minutes to obtain the product.

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