A method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant

Abstract

The application discloses a preparation method of moisture-curable alkoxysilicon-terminated polyacrylate sealant, and relates to the technical field of silane-terminated polyether sealant, and comprises the following processes: step one: taking alkoxysilicon-terminated polyacrylate, mixing with calcium carbonate and heating; adding a water-removing agent, stirring and mixing to obtain a first mixture; step two: adding aminosiloxane, an epoxy curing agent and an ultraviolet absorber into the first mixture, vacuum stirring for 30-60 minutes to obtain a second mixture; and step three: vacuum mixing the second mixture, epoxy-silicone, epoxy resin, a toughening agent, a filler, a catalyst and an auxiliary accelerator at 30-65 DEG C to obtain the sealant, wherein no toxic and harmful gas is generated in the curing process, the problems of construction safety and slow deep curing in cold weather are solved, the adhesion to a base material is strong, the sealant can be brushed, and good usability is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silane-terminated polyether sealant, in particular to a preparation method of a moisture-cured alkoxysilane-terminated polyacrylate sealant. BACKGROUND

[0002] The silane-terminated polyether resin is a technical product obtained by using a silane terminating agent containing active groups to terminate polyether. The advantage of the resin is that it releases colorless and odorless small molecular alcohol after curing, which is more safe and environmentally friendly, and has good surface brushability and other excellent properties. Since the silane-terminated polyether resin is a silane-modified polyether material, the performance of the resin combines the double advantages of silicone and polyurethane, so that the weather resistance of the material itself and the strength of the prepared glue have good performance.

[0003] The most widely used silane-terminated polyether resin is used as a component to prepare a silane-terminated polyether sealant, which can solve many shortcomings of the silicone sealant currently used in the industry, including the generation of irritating odor during curing, the unbrushable surface, oil penetration and other problems. Compared with polyurethane glue, the silane-terminated polyether sealant has better weather resistance, does not contain free isocyanate, and does not contain organic solvents. This kind of silane-terminated polyether sealant maximizes the advantages of silicone glue and polyurethane glue, while avoiding the disadvantages of silicone glue and polyurethane glue, such as insufficient environmental protection, poor storage resistance, narrow use range, etc. Its performance has been improved in all directions, and it can be widely used in various fields. The development of silane-terminated polyether sealant greatly enriches the prospects of high-end sealants in the world.

[0004] At present, this kind of glue is a high-end glue product in the market, and most of the raw material suppliers come from foreign large companies such as Wacker, Covestro and Wanhua. In various industrial production activities in China, the development of domestic sealants started late, and most of the high-end sealants need to be imported. The academic research and industrial transformation of new sealants still need to be further improved. With the continuous prosperity of China's economy, the market demand for high-performance sealants is expected to further increase. Related researchers need to further explore the synthesis mechanism and preparation method of silane-modified polymers, pursue more advanced production processes, and achieve better comprehensive performance. Therefore, we propose a preparation method of a moisture-cured alkoxysilane-terminated polyacrylate sealant. SUMMARY

[0005] The purpose of the present application is to provide a preparation method of a moisture-cured alkoxysilane-terminated polyacrylate sealant to solve the problems in the background art.

[0006] In order to solve the above technical problems, the present application provides the following technical scheme: a preparation method of a moisture-cured alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0007] Step one: take the alkoxysilane terminated polyacrylate, mix with calcium carbonate, heat; add water scavenger, stir and mix to obtain a first mixture;

[0008] Step two: to the first mixture obtained in step one, add amino siloxane, epoxy curing agent and ultraviolet absorber, vacuum stirring for 30-60 min to obtain a second mixture;

[0009] Step three, vacuum mix the second mixture obtained in step two, epoxy siloxane, epoxy resin, toughening agent, filler, catalyst and co-promoter at 30-65°C to obtain a sealant.

[0010] Further, the sealant comprises the following mass components: 100 parts of alkoxysilane terminated polyacrylate, 50-200 parts of calcium carbonate, 3-10 parts of water scavenger, 0.2-3.0 parts of amino siloxane, 18-40 parts of epoxy curing agent, 0.1-1.0 parts of ultraviolet absorber, 0.2-3.0 parts of epoxy siloxane, 50-100 parts of epoxy resin, 20-30 parts of toughening agent, 20-75 parts of filler, 0.1-1.0 parts of catalyst, 1.0-2.5 parts of co-promoter.

[0011] Further, in step one, the heating process is: vacuum for 12 h at a temperature of 100-120°C; then cool to 18-40°C.

[0012] Further, in step one, the stirring and mixing process conditions are: temperature 18-40°C, vacuum stirring for 15-40 min.

[0013] Further, the water scavenger is one or more of siloxane water scavenger, oxazolidine water scavenger, molecular sieve;

[0014] The siloxane water scavenger is one or more of vinyl trimethoxysilane, vinyl triethoxysilane, tetramethoxysilane.

[0015] Further, the catalyst is an organotin compound, and the organotin compound is dibutyltin dilaurate and chelated organotin compound;

[0016] The co-promoter is one or more of stabilizer, adhesion promoter, and substrate wetting agent.

[0017] Further, the amino siloxane is one or more of N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane (KH792), N-phenyl-γ-aminopropyl triethoxysilane, N-ethyl-γ-aminopropyl trimethoxysilane, γ-aminopropyl triethoxysilane;

[0018] The epoxy curing agent is one or more of a polyamide curing agent, a fatty amine curing agent, a phenolic amine curing agent, and a ketimine curing agent;

[0019] The ultraviolet absorber is one or more of 2,4-dihydroxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, and 2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzotriazole;

[0020] The epoxy siloxane is γ-(2,3-epoxypropoxy)propyl trimethoxysilane;

[0021] The epoxy resin is one or more of bisphenol F epoxy resin, bisphenol A epoxy resin, phenolic epoxy resin, o-cresol epoxy resin, and tetrafunctional glycidyl amine epoxy resin.

[0022] The filler is one or more of talc, kaolin, silica, diatomite, titanium dioxide, silicon powder, zinc phosphate, aluminum oxide, and glass fiber.

[0023] Further, the alkoxysilane-terminated polyacrylate is prepared by the following process:

[0024] The alkoxysilane-terminated polyacrylate is obtained by mixing the acrylic resin, isocyanate silane, and organic tin catalyst at a temperature of 40-50°C and reacting for 3-6 hours.

[0025] Further, the alkoxysilane-terminated polyacrylate has the following mass components: 1000-1200 parts of acrylic resin, 0.44-0.86 parts of organic tin catalyst, and 39-60 parts of isocyanate silane.

[0026] Further, the alkoxysilane-terminated polyacrylate is prepared by the following process:

[0027] The alkoxysilane-terminated polyacrylate is obtained by mixing the acrylic resin, organic polyisocyanate, and 83-91% mass parts of organic tin catalyst at a temperature of 40-50°C and reacting for 3-6 hours.

[0028] The temperature is then raised to 60-70°C, and then the isocyanate silane is added, the remaining organic tin catalyst is added, and the reaction is continued for 2-3 hours to obtain the alkoxysilane-terminated polyacrylate.

[0029] Further, the alkoxysilane-terminated polyacrylate has the following mass components: 1000-1200 parts of acrylic resin, 4-8 parts of organic polyisocyanate, 0.44-1.25 parts of organic tin catalyst, and 39-60 parts of isocyanate silane.

[0030] Further, after the preparation of the alkoxysilane-terminated polyacrylate, the temperature is lowered to 20-40°C, and vinyltrimethoxysilane is added as a water-removing agent, and stirred for 30-60 minutes, and the product is discharged for use.

[0031] Further, the polyether polyol has a functionality of 2 and a number average molecular weight of 4000-20000.

[0032] Further, the organic polyisocyanate is one or more of toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate.

[0033] Further, the isocyanate silane is isocyanatomethyl triethoxysilane.

[0034] Further, the organotin catalyst is dibutyltin dilaurate and chelated organotin compounds.

[0035] Further, the acrylic resin is prepared by the following process:

[0036] Butyl acrylate, methyl methacrylate, hydroxyethyl acrylate, mercaptoethanol, and 80-90% by mass of an initiator are mixed to obtain a mixed solution;

[0037] The mixed solution is slowly added to the polyether polyol, and the addition is completed in 3-5 hours; after the addition is completed, the reaction is maintained for 1-2 hours; the remaining initiator is added, and the reaction is continued for 1-2 hours;

[0038] The temperature is raised to 120-130°C, and vacuum is applied for 1-3 hours to remove unreacted mercaptoethanol; the temperature is lowered to 40-60°C, and the product is discharged to obtain the acrylic resin.

[0039] Further, the acrylic resin comprises the following mass components: 1000 parts of polyether polyol, 100-200 parts of the mixed solution;

[0040] The mixed solution comprises the following mass components: 600-800 parts of butyl acrylate, 50-150 parts of methyl methacrylate, 10-20 parts of hydroxyethyl acrylate, 5.5-12.0 parts of an initiator, and 5-10 parts of mercaptoethanol.

[0041] Further, the polyether polyol is dehydrated before use; then the temperature is lowered to 30-50°C, and the organic polyisocyanate is mixed, the temperature is raised to 65-75°C, and the reaction is maintained for 2-4 hours, and the product is recorded as a hydroxyl-terminated prepolymer.

[0042] Further, the mixing temperature is 35-45°C, and the reaction temperature is 70-75°C.

[0043] Further, the amount of the organic polyisocyanate is 0.4%-1.5% of the mass of the polyether polyol.

[0044] Further, in the preparation component of the alkoxysilane-terminated polyacrylate, when the hydroxyl-terminated prepolymer is used to replace the polyether polyol, the amount of isocyanate silane is 2% to 5% of the hydroxyl-terminated prepolymer, and more preferably 3% to 4%;

[0045] The addition temperature of the isocyanate silane is 40 to 60°C, and more preferably 50 to 55°C.

[0046] The reaction time after the addition of the isocyanate silane is 2 to 4 hours.

[0047] Further, the dehydration process of the polyether polyol is to heat to 100 to 130°C and vacuum for 1 to 3 hours; after dehydration, the moisture is below 200 ppm.

[0048] In the above technical solution, the polyether polyol is reacted with the acrylic monomer to prepare an acrylic resin; then the acrylic resin is reacted with siloxane and mixed with other components to obtain an alkoxysilane-terminated polyacrylate sealant material, which does not contain free isocyanate, can effectively prevent the foaming of the sealant, releases small molecular alcohol substances after the resin is cured, has low VOC emission characteristics, is environmentally friendly and pollution-free, and has fast deep curing, can be applied to the bonding and sealing between structures, and the cured product has high modulus, high strength, and certain elongation at break, and has good usability as a bonding and sealing material.

[0049] The modulus of the gel obtained after the alkoxysilane-terminated polyacrylate and N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane (KH792) are uniformly mixed and cured in air for one week is 0.4 MPa to 1.0 MPa, has a relatively low Young's modulus, the colloid has good water compatibility and mechanical properties, and has good adhesion to the wet matrix; the prepared sealant has higher elasticity, can better adapt to the sealing shape and deformation conditions, is conducive to the improvement of the sealing performance of the sealant; and can improve stress transmission and relieve stress concentration, avoid the risk of fracture caused by stress concentration, and improve fatigue life. And the modulus is appropriate, which can avoid the phenomenon of extrusion and flow of the prepared sealant due to too high elasticity, and affect the sealing performance and service life.

[0050] In the above technical solution, the sealant component also adds epoxy resin and epoxy curing agent, epoxy agent siloxane, which can participate in curing, can play a film-forming agent role, has good adhesion and thermal stability, and cooperates with the alkoxysilane-terminated polyacrylate to increase the bonding strength between the prepared sealant and the base material and improve the service life.

[0051] The introduction of the toughening agent can relieve the brittleness of the epoxy resin and its curing system, improve the toughness and impact resistance of the prepared sealant, and improve the resistance to external impact and vibration. The use of fillers can significantly improve the mechanical properties of the sealant, reduce the amount of resin, reduce the cost, adjust the thermal expansion coefficient, thermal conductivity, heat resistance and other physical properties of the sealant, and also improve the thixotropy and flowability of the glue solution, which is beneficial to operation and processing.

[0052] Further, the epoxy resin can be replaced by an organosiliconated episulfide resin, which is prepared by the following process:

[0053] The diallyl episulfide resin, hydrogen silane and toluene are mixed and heated to 30-50℃, and then a platinum catalyst is added. The temperature is raised to 70-75℃, and the reaction is carried out at constant temperature for 65-120min to obtain the organosiliconated episulfide resin.

[0054] Further, the molar ratio of the allyl double bond in the diallyl episulfide resin to the silicon-hydrogen bond in the hydrogen silane is 1:(1.1-1.2);

[0055] The platinum catalyst is chloroplatinic acid / isopropanol solution, and the amount of chloroplatinic acid is 1 / 4200-1 / 2100 of the molar amount of the allyl double bond;

[0056] The ratio of diallyl episulfide resin to toluene is 80g / 100mL.

[0057] In the above technical solution, due to its own characteristics, the cured epoxy resin has high brittleness, high thermal stress concentration, easy delamination at low temperature, and almost zero adhesion to a humid substrate. Therefore, the episulfide resin containing an allyl double bond is selected, which is added to the hydrogen silane under the action of a platinum catalyst to introduce a moisture-curable silane structure, so that the epoxy resin component (organosiliconated episulfide resin) has more excellent water compatibility and mechanical properties, which can improve the adhesion of the epoxy resin component to the humid substrate, help to improve stress transfer and improve the fatigue resistance of the sealant. The modification of the epoxy resin by organosilicon improves the structure of the molecular chain of the epoxy resin, effectively improves the toughness, reduces the viscosity, and helps to improve the mechanical properties, processing flowability, low temperature resistance, heat resistance, water resistance and other abilities.

[0058] Further, the diallyl episulfide resin is prepared by the following process:

[0059] Mixing 4,4'-diallyl bisphenol A, epichlorohydrin and tetramethyl ammonium bromide, under the protection of nitrogen atmosphere, heating to 90-100℃ for 100-150min; cooling to 80-85℃, slowly adding sodium hydroxide solution, continue to react for 30-40min; 120℃, remove excess epichlorohydrin by distillation under reduced pressure, add toluene to dissolve, wash with deionized water, add lye, 80-90℃ for 100-150min, adjust the pH of the system to neutral, water washing, distillation to remove toluene, to obtain a diallyl bisphenol A type epoxy resin;

[0060] Mixing deionized water and ethanol, adding diallyl bisphenol A type epoxy resin, 88-91% of the mass of potassium thiocyanate, reacting at 30-35℃ for 60-90min; adding the remaining potassium thiocyanate, continue to react for 150-200min; adding chloroform to separate the layers, taking the lower organic phase, washing with water until neutral, separating the layers and drying with anhydrous sodium sulfate, filtering, rotary evaporation, to obtain a diallyl ring sulfur resin.

[0061] Further, the mass ratio of 4,4'-diallyl bisphenol A, epichlorohydrin, tetramethyl ammonium bromide is (31-35):100:(1.0-1.1);

[0062] The ratio of 4,4'-diallyl bisphenol A and sodium hydroxide solution (48wt%) is 100g:(50-55)mL;

[0063] The lye is 5wt% sodium hydroxide solution.

[0064] Further, the mass ratio of diallyl bisphenol A type epoxy resin and potassium thiocyanate is 1:(1.0-1.1);

[0065] The ratio of diallyl bisphenol A type epoxy resin, deionized water and ethanol is 10:(255-260)mL:(516-688)mL.

[0066] In the above technical solution, 4,4'-diallyl bisphenol A reacts with epichlorohydrin in the presence of catalyst tetramethyl ammonium bromide, and is epoxidized to obtain a diallyl bisphenol A type epoxy resin; then the epoxy group is ring-sulfurized with potassium thiocyanate to form a diallyl ring sulfur resin, which retains the double bond required for hydrosilylation and also obtains a ring sulfur group, which has a longer bond length and bond angle and better reactivity than the epoxy group, thereby promoting the epoxy resin component (silicone ring sulfur resin) in the sealant to have a faster curing speed, higher low-temperature reactivity, lower shrinkage, and a cured product with higher glass transition temperature, heat resistance and mechanical properties; the sealant has more excellent water resistance, lower interaction with the substrate, and better wettability and adhesion to the substrate.

[0067] Further, the hydrosilane is prepared by the following process:

[0068] The dimercapto diphenyl ether compound is mixed with sodium hydroxide solution, heated to 38-43°C, 3,5-dichloronitrobenzene is added, and refluxed for 5-6 hours. Ethyl acetate is used for extraction, the oil layer is combined, acidified, filtered, washed with water, and dried to obtain the phenyl sulfide compound.

[0069] The phenyl sulfide compound, palladium / carbon catalyst, and anhydrous ethanol are mixed, heated to 70-75°C, hydrazine hydrate is slowly added, and refluxed for 7-8 hours. Activated carbon is added for decolorization for 15-20 minutes, filtered while hot to remove the catalyst and activated carbon, distilled water is added, filtered, and recrystallized with methanol and water to obtain the aminophenyl sulfide compound.

[0070] The aminophenyl sulfide compound, bismaleimide-dipolyethylene glycol, and isopropyl alcohol are mixed, a catalyst is added, heated to 83-88°C, and refluxed for 12-36 hours. 1-propanethiol-2-dimethoxysilane is added, and the reaction is continued for 12-16 hours. Distilled under reduced pressure, washed, and dried to obtain the hydrosilane.

[0071] Further, the dimercapto diphenyl ether compound is one or more of 4,4'-dimercaptodiphenyl ether, 4,4-dimercaptodiphenyl sulfide, 4,4'-thiobis[3,5-dimethyl]-benzenethiol (CAS No. 599164-35-9);

[0072] The molar ratio of the dimercapto diphenyl ether compound to 3,5-dichloronitrobenzene is (1.2-2.0):1;

[0073] The molar ratio of the dimercapto diphenyl ether compound to sodium hydroxide is 1:(2.0-2.1); the concentration of the sodium hydroxide solution is 13-15%.

[0074] Further, the mass ratio of the phenyl sulfide compound, hydrazine hydrate, and palladium / carbon catalyst is 10:(16-18):(0.25-0.35);

[0075] The ratio of the phenyl sulfide compound to anhydrous ethanol is (8-9) g / 100 mL.

[0076] Further, the mass ratio of the aminophenyl sulfide compound, bismaleimide-dipolyethylene glycol (CAS No. 1070882-80-2), and 1-propanethiol-2-dimethoxysilane (CAS No. 94099-12-4) is 1:(1.68-1.77):(0.62-0.66);

[0077] The catalyst is BF3·OEt2, and the amount used is 5.0-6.5% of the mass of the aminophenyl sulfide;

[0078] The ratio of the amino phenyl sulfide compound and isopropanol is (5-10) g / 100 mL.

[0079] In the above technical solution, the dimercapto phenyl ether compound is reacted with 3,5-dichloronitrobenzene to obtain a phenyl sulfide compound; the formation of the phenyl sulfide chain segment can significantly improve the strength of the epoxy resin component and help to improve the mechanical properties and water resistance and heat resistance of the prepared sealant.

[0080] Then, the nitro group (3,5-dichloronitrobenzene residue) in the structure thereof is converted into an amino group to obtain a phenyl sulfide compound with an amino branched chain, which is denoted as an amino phenyl sulfide compound and has a double bond addition multifunctionality; the addition of the product to a maleimide in a bismaleimide-diphenyl glycol can improve the cohesive strength of the epoxy resin component, enhance the toughness of the epoxy resin component, and improve the strength and high-temperature resistance of the sealant, which is conducive to the improvement of the mechanical properties, heat resistance, reduction of processing difficulty, improvement of durability, improvement of service life and reliability.

[0081] Finally, 1-propanethiol-2-dimethoxysilane is used to introduce a moisture-curable silane, and thus the hydrogen silane described in the previous process is obtained. The hydrogen silane also has a silane-terminated polyether chain segment, which can be hydrolyzed to form Si-OH under the action of moisture, can form a chemical bond or a hydrogen bond with a substrate, and can enhance the adhesion of the sealant to the substrate, the mechanical properties of the sealant, the low-temperature resistance, the heat resistance, and the water resistance of the sealant, so that the durability of the sealant is improved. The hydrogen silane has a branched chain structure, and reacts with a diallyl cyclic sulfide resin to form an epoxy resin component with a branched structure, and the crosslinking degree in the sealant system is improved, which directly affects the modulus and strength of the sealant and improves the mechanical properties and heat resistance of the sealant. In combination with the cyclic sulfide group, the long and short chains of the crosslinking chain form an interpenetrating network in the sealant system, which makes the prepared sealant have more excellent mechanical properties and durable use ability. DETAILED DESCRIPTION

[0082] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative labor fall within the protection scope of the present application.

[0083] In the following specific embodiments, the "parts" are all mass parts;

[0084] The water removing agent is a siloxane type water removing agent, vinyl trimethoxysilane;

[0085] The catalyst is an organic tin compound, and the organic tin compound is dibutyltin dilaurate;

[0086] The co-promoter is a mixture of Tinuvin 770DF, an adhesion promoter ADP, and TEGO 245, a substrate wetting agent.

[0087] The aminosiloxane is N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

[0088] The epoxy curing agent is a mixture of EPIKURE 3175, a polyamide curing agent, D230, a polyetheramine curing agent, and T31, a phenolic amine curing agent, in a mass ratio of 4.5:1:1.2, respectively from Huntsman, Momentive, and Tianjin Sanhe;

[0089] The ultraviolet absorber is a mixture of 2,4-dihydroxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, and 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole in a mass ratio of 2:1:1.

[0090] The epoxy silane is γ-(2,3-epoxypropoxy)propyltrimethoxysilane.

[0091] The epoxy resin is bisphenol A epoxy resin CYD-128 from Baling Branch of China Petroleum Chemical Co., Ltd.

[0092] The toughening agent is polytetramethylene ether glycol bis-p-aminobenzoate.

[0093] The fillers include light calcium carbonate LJ-1250, heavy calcium carbonate LJ-800, and titanium white B101-B in a mass ratio of 100:55:15, all from Shanghai Liangjiang Titanium White Chemical Products Co., Ltd.

[0094] The polyether polyol is DL-18000 with a functionality of 2, a number average molecular weight of 8000, and a GPC molecular weight distribution of 1.1 from Shandong Lansheng Dongda Co., Ltd. The polyether polyol is dehydrated before use by heating to 110°C and vacuumizing for 3 hours, after which the moisture is below 200 ppm.

[0095] The organic polyisocyanate is hexamethylene diisocyanate from BASF.

[0096] The isocyanate silane is isocyanatomethyltriethoxysilane.

[0097] The organic tin catalyst is dibutyltin dilaurate.

[0098] The calcium carbonate is nano calcium carbonate from Ruicheng Xintai Nanometer Material Co., Ltd.

[0099] The palladium / carbon catalyst is 10% Pd from National Pharmaceutical Group Chemical Reagent Co., Ltd.

[0100] Chloroplatinic acid / isopropanol solution: Pt content 1000 ppm, from Beijing Bailingwei Technology Co., Ltd.

[0101] The diallyl cyclic sulfide resin was prepared by the following process:

[0102] 4,4'-diallyl bisphenol A, epichlorohydrin and tetramethyl ammonium bromide were mixed, and the temperature was raised to 95℃ under nitrogen atmosphere for 120 min; the temperature was lowered to 82℃, and sodium hydroxide solution was slowly added, and the reaction was continued for 35 min; excess epichlorohydrin was removed by distillation at 120℃ under reduced pressure, and toluene was added for dissolution, and deionized water was washed, and 5wt% sodium hydroxide solution was added, and the reaction was continued at 85℃ for 120 min, and the pH of the system was adjusted to neutral, and water was washed, and toluene was removed by distillation, to obtain a diallyl bisphenol A type epoxy resin; the mass ratio of 4,4'-diallyl bisphenol A, epichlorohydrin and tetramethyl ammonium bromide was 33:100:1.05; the ratio of 4,4'-diallyl bisphenol A and sodium hydroxide solution (48wt%) was 100g:52mL;

[0103] Deionized water and ethanol were mixed, and diallyl bisphenol A type epoxy resin and 90% of the mass of potassium thiocyanate were added, and the reaction was continued at 32℃ for 75 min; the remaining potassium thiocyanate was added, and the reaction was continued for 180 min; chloroform was added for phase separation, and the lower organic phase was washed with water until neutral, and was separated and dried with anhydrous sodium sulfate, and was filtered, and was rotary evaporated, to obtain a cyclic sulfide resin; the mass ratio of diallyl bisphenol A type epoxy resin and potassium thiocyanate was 1:1.05; the ratio of diallyl bisphenol A type epoxy resin, deionized water and ethanol was 10:258mL:602mL;

[0104] After the preparation of the alkoxysilane-terminated polyacrylate, the temperature was lowered to 30℃, 3% water-removing agent vinyltrimethoxysilane was added, and stirring was continued for 30 min, and the product was discharged.

[0105] Example 1: A preparation method of a moisture-curable alkoxysilane-terminated polyacrylate sealant, comprising the following process:

[0106] (1) 600 parts of butyl acrylate, 100 parts of methyl methacrylate, 20 parts of hydroxyethyl acrylate, 10 parts of mercaptoethanol and 5 parts of initiator were mixed to obtain a mixed solution; 160 parts of the mixed solution was slowly added to 1000 parts of polyether polyol, and the addition was completed in 5 h; after the addition was completed, the reaction was continued for 1 h; 1 part of initiator was added, and the reaction was continued for 1 h; the temperature was raised to 120℃, and vacuum was applied for 3 h to remove unreacted mercaptoethanol, to obtain an acrylic resin;

[0107] (2) The temperature was lowered to 40℃, 45.57 parts of isocyanate silane and 0.51 parts of organotin catalyst were mixed, and the reaction was continued for 6 h, to obtain an alkoxysilane-terminated polyacrylate;

[0108] (3) take the alkoxysilane-terminated polyacrylate, mixed with calcium carbonate, at a temperature of 100°C, vacuum for 12h; cooling to 18°C; adding water scavenger, stirring and mixing to obtain the first mixture; adding amino siloxane, epoxy curing agent and ultraviolet absorber, vacuum stirring for 30min, to obtain the second mixture;

[0109] The second mixture, epoxy siloxane, epoxy resin, toughening agent, filler, catalyst and co-promoter are mixed at 30°C under vacuum to obtain the sealant; the moisture-cured alkoxysilane-terminated polyacrylate sealant comprises the following mass components: 100 parts of alkoxysilane-terminated polyacrylate, 120 parts of calcium carbonate, 7 parts of water scavenger, 3.0 parts of amino siloxane, 18 parts of epoxy curing agent, 0.5 parts of ultraviolet absorber, 3.0 parts of epoxy siloxane, 50 parts of epoxy resin, 20 parts of toughening agent, 50 parts of filler, 0.5 parts of catalyst, 1.5 parts of co-promoter.

[0110] Example 2: A preparation method of a moisture-cured alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0111] (1) 600 parts of butyl acrylate, 100 parts of methyl methacrylate, 20 parts of hydroxyethyl acrylate, 10 parts of mercaptoethanol and 5 parts of initiator are mixed to obtain a mixed solution; 200 parts of the mixed solution is slowly added to 1000 parts of polyether polyol, and the addition is completed in 4h; after the addition is completed, the reaction is maintained for 1.5h; 1 part of initiator is added, and the reaction is continued for 1.5h; the temperature is raised to 125°C, and vacuum is applied for 2h to remove unreacted mercaptoethanol; the temperature is lowered to 50°C, and the product is discharged to obtain an acrylic resin;

[0112] (2) 51.42 parts of isocyanate silane and 0.51 parts of organotin catalyst are mixed and reacted for 4.5h to obtain an alkoxysilane-terminated polyacrylate;

[0113] (3) take the alkoxysilane-terminated polyacrylate, mixed with calcium carbonate, at a temperature of 110°C, vacuum for 12h; cooling to 25°C; adding water scavenger, stirring and mixing to obtain the first mixture; adding amino siloxane, epoxy curing agent and ultraviolet absorber, vacuum stirring for 45min, to obtain the second mixture;

[0114] The second mixture, epoxy siloxane, epoxy resin, toughening agent, filler, catalyst and co-promoter are mixed at 45°C under vacuum to obtain the sealant; the moisture-cured alkoxysilane-terminated polyacrylate sealant comprises the following mass components: 100 parts of alkoxysilane-terminated polyacrylate, 120 parts of calcium carbonate, 7 parts of water scavenger, 1.5 parts of amino siloxane, 30 parts of epoxy curing agent, 0.5 parts of ultraviolet absorber, 1.5 parts of epoxy siloxane, 75 parts of epoxy resin, 25 parts of toughening agent, 50 parts of filler, 0.5 parts of catalyst, 1.5 parts of co-promoter.

[0115] Example 3: A preparation method of a moisture-cured alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0116] (1) 800 parts of butyl acrylate, 150 parts of methyl methacrylate, 15 parts of hydroxyethyl acrylate, 15 parts of mercaptoethanol and 8 parts of initiator were mixed to obtain a mixed solution; 200 parts of the mixed solution were slowly added to 1000 parts of polyether polyol, and the addition was completed in 3h; after the addition was completed, the reaction was kept for 2h; 2 parts of initiator were added, and the reaction was continued for 2h; the temperature was raised to 130℃, and vacuum was applied for 1h to remove unreacted mercaptoethanol; the temperature was lowered to 60℃, and the product was discharged to obtain an acrylic resin;

[0117] (2) 45.57 parts of isocyanate silane and 0.51 parts of organotin catalyst were mixed and reacted for 3h to obtain an alkoxysilane-terminated polyacrylate;

[0118] (3) The alkoxysilane-terminated polyacrylate was mixed with calcium carbonate, vacuum was applied at a temperature of 120℃ for 12h; the temperature was lowered to 40℃; a water removal agent was added and stirred to obtain a first mixture; amino siloxane, epoxy curing agent and ultraviolet absorber were added, and vacuum stirring was performed for 60min to obtain a second mixture;

[0119] The second mixture, epoxy siloxane, epoxy resin, toughening agent, filler, catalyst and co-promoter were mixed at 65℃ under vacuum to obtain a sealant; the moisture-cured alkoxysilane-terminated polyacrylate sealant comprises the following mass components: 100 parts of alkoxysilane-terminated polyacrylate, 120 parts of calcium carbonate, 7 parts of water removal agent, 0.2 parts of amino siloxane, 40 parts of epoxy curing agent, 0.5 parts of ultraviolet absorber, 0.2 parts of epoxy siloxane, 100 parts of epoxy resin, 30 parts of toughening agent, 50 parts of filler, 0.5 parts of catalyst and 1.5 parts of co-promoter.

[0120] Example 4: A preparation method of a moisture-cured alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0121] (1) 600 parts of butyl acrylate, 100 parts of methyl methacrylate, 20 parts of hydroxyethyl acrylate, 10 parts of mercaptoethanol and 5 parts of initiator were mixed to obtain a mixed solution; 100 parts of the mixed solution were slowly added to 1000 parts of polyether polyol, and the addition was completed in 5h; after the addition was completed, the reaction was kept for 1h; 1 part of initiator was added, and the reaction was continued for 1h; the temperature was raised to 120℃, and vacuum was applied for 3h to remove unreacted mercaptoethanol to obtain an acrylic resin;

[0122] (2) The temperature was lowered to 40℃, 45.57 parts of isocyanate silane and 1.0 parts of organotin catalyst were mixed and reacted for 6h; the product was discharged to form a prepolymer to obtain an alkoxysilane-terminated polyacrylate;

[0123] Step (3) is the same as that of Example 1 to obtain a sealant.

[0124] Example 5: A method for preparing a moisture-curable alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0125] (3) The phenyl sulfide compound is mixed with a 13% sodium hydroxide solution, heated to 38°C, and 3,5-dichloronitrobenzene is added, and refluxed for 5h; extracted with ethyl acetate, combined the oil layer, acidified, filtered, washed with water, and dried to obtain a phenyl sulfide compound; the phenyl sulfide compound is 4,4'-dithiobisphenyl ether; the molar ratio of the phenyl sulfide compound to 3,5-dichloronitrobenzene is 2:1; the molar ratio of the phenyl sulfide compound to sodium hydroxide is 1:2;

[0126] The phenyl sulfide compound, palladium / carbon catalyst and anhydrous ethanol are mixed, heated to 70°C, and hydrazine hydrate is slowly added, and refluxed for 7h; decolorized with activated carbon for 15min, and filtered hot to remove the catalyst and activated carbon, and distilled water is added, filtered, and recrystallized with methanol and water to obtain an aminophenyl sulfide compound; the mass ratio of the phenyl sulfide compound, hydrazine hydrate, and palladium / carbon catalyst is 10:16:0.25; the ratio of the phenyl sulfide compound to anhydrous ethanol is 8.5g / 100mL;

[0127] The aminophenyl sulfide compound, bismaleimide-dipropylene glycol and isopropanol are mixed, a catalyst is added, heated to 83°C, and refluxed for 12h; 1-propanethiol-2-dimethoxysilane is added, and the reaction is continued for 12h; distilled under reduced pressure, washed, and dried to obtain a hydrosilane; the mass ratio of the aminophenyl sulfide compound, bismaleimide-dipropylene glycol, and 1-propanethiol-2-dimethoxysilane is 1:1.68:0.62; the catalyst is BF3·OEt2, and the amount used is 5.0% of the mass of the aminophenyl sulfide compound; the ratio of the aminophenyl sulfide compound to isopropanol is 10g / 100mL;

[0128] The diallyl cyclic sulfide resin, hydrosilane, and toluene are mixed, heated to 30°C, and a platinum catalyst is added; heated to 70°C, and reacted at constant temperature for 65min to obtain a silicone-cured cyclic sulfide resin; the molar ratio of the allyl double bond and the silicon-hydrogen bond is 1:1.1; the platinum catalyst is chloroplatinic acid / isopropanol solution, and the amount of chloroplatinic acid used is 1 / 4200 of the molar amount of the allyl group; the ratio of the diallyl cyclic sulfide resin to toluene is 80g / 100mL;

[0129] Steps (1-2, 4) are the same as (1-3) in Example 1, and the epoxy resin is replaced with a silicone-cured cyclic sulfide resin to obtain a sealant.

[0130] Example 6: A method for preparing a moisture-curable alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0131] (1) 600 parts of butyl acrylate, 100 parts of methyl methacrylate, 20 parts of hydroxyethyl acrylate, 10 parts of mercaptoethanol and 5 parts of initiator were mixed to obtain a mixed solution; the polyether polyol was dehydrated before use; then the temperature was lowered to 30°C, and an organic polyisocyanate (1.0% of the mass of the polyether polyol) was added, mixed at 40°C, the temperature was raised to 70°C, and reacted for 3h to obtain a hydroxyl-terminated prepolymer; 160 parts of the mixed solution was slowly added to 1000 parts of the hydroxyl-terminated prepolymer, and the addition was completed in 5h; after the addition was completed, the reaction was maintained for 1h; 0.5 parts of initiator was added, and the reaction was continued for 1h; the temperature was raised to 120°C, and vacuum was applied for 3h to remove unreacted mercaptoethanol, to obtain an acrylic resin;

[0132] (2) The temperature was lowered to 55°C, 45.57 parts of isocyanate silane, 0.51 parts of organotin catalyst were mixed and reacted for 4h to obtain an alkoxysilane-terminated polyacrylate;

[0133] (3) The dimercapto diphenyl ether compound was mixed with 14% sodium hydroxide solution, the temperature was raised to 40°C, 3,5-dichloronitrobenzene was added, and refluxed for 5.5h; extracted with ethyl acetate, combined the oil layer, acidified, filtered, washed with water, and dried to obtain a phenyl sulfide compound; the dimercapto diphenyl ether compound was 4,4-dimercapto diphenyl sulfide; the molar ratio of the dimercapto diphenyl ether compound to 3,5-dichloronitrobenzene was 1.6:1; the molar ratio of the dimercapto diphenyl ether compound to sodium hydroxide was 1:2.05;

[0134] The phenyl sulfide compound, palladium / carbon catalyst and anhydrous ethanol were mixed, the temperature was raised to 72°C, hydrazine hydrate was slowly added, and refluxed for 7.5h; activated carbon was added for decolorization for 18min, the catalyst and activated carbon were removed by hot filtration, distilled water was added, filtered, recrystallized with methanol and water to obtain an aminophenyl sulfide compound; the mass ratio of the phenyl sulfide compound, hydrazine hydrate and palladium / carbon catalyst was 10:17:0.30; the ratio of the phenyl sulfide compound to anhydrous ethanol was 8.5g / 100mL;

[0135] The aminophenyl sulfide compound, bismaleimide-dipolyethylene glycol and isopropanol were mixed, a catalyst was added, heated to 85°C, and refluxed for 24h; 1-propanethiol-2-dimethoxysilane was added, and the reaction was continued for 14h; vacuum distillation, washing and drying were performed to obtain a hydrosilane; the mass ratio of the aminophenyl sulfide compound, bismaleimide-dipolyethylene glycol and 1-propanethiol-2-dimethoxysilane was 1:1.72:0.64; the catalyst was BF3·OEt2, and the amount was 5.8% of the mass of the aminophenyl sulfide; the ratio of the aminophenyl sulfide compound to isopropanol was 8g / 100mL;

[0136] The diallyl cyclic sulfide resin, hydrogen silane and toluene are mixed, heated to 40℃, and then a platinum catalyst is added; the temperature is raised to 72℃, and constant temperature reaction is carried out for 90 min to obtain a siliconized cyclic sulfide resin; the molar ratio of the allyl double bond in the diallyl cyclic sulfide resin and the silicon hydrogen bond in the hydrogen silane is 1:1.15; the platinum catalyst is chloroplatinic acid / isopropanol solution, and the amount of chloroplatinic acid is 1 / 3100 of the molar amount of the allyl double bond; the ratio of the diallyl cyclic sulfide resin and toluene is 80 g / 100 mL;

[0137] Step (4) is the same as (3) in Example 1, and the epoxy resin is replaced by a siliconized cyclic sulfide resin to obtain a sealant.

[0138] Example 7: A preparation method of a moisture-curable alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0139] (2) 6 parts of an organic polyisocyanate and 0.85 parts of an organotin catalyst are added and mixed, and reaction is carried out for 3.5 h; the temperature is raised to 65℃, then 39 parts of isocyanate silane and 0.15 parts of an organotin catalyst are added, and reaction is continued for 2.5 h to obtain an alkoxysilane-terminated polyacrylate;

[0140] (3) The dimercapto diphenyl ether compound is mixed with 15% sodium hydroxide solution, the temperature is raised to 43℃, and 3,5-dichloronitrobenzene is added, and reflux reaction is carried out for 6 h; ethyl acetate is used for extraction, the oil layer is combined, acidified, filtered, washed with water, and dried to obtain a phenyl sulfide compound; the dimercapto diphenyl ether compound is 4,4'-thiobis[3,5-dimethyl]-benzenethiol; the molar ratio of the dimercapto diphenyl ether compound and 3,5-dichloronitrobenzene is 1.2:1; the molar ratio of the dimercapto diphenyl ether compound and sodium hydroxide is 1:2.1;

[0141] The phenyl sulfide compound, palladium / carbon catalyst and anhydrous ethanol are mixed, the temperature is raised to 75℃, and hydrazine hydrate is slowly added, and reflux reaction is carried out for 8 h; activated carbon is added for decolorization for 20 min, and the catalyst and activated carbon are removed by hot filtration, distilled water is added, filtered, and recrystallized with methanol and water to obtain an aminophenyl sulfide compound; the mass ratio of the phenyl sulfide compound, hydrazine hydrate and palladium / carbon catalyst is 10:18:0.35; the ratio of the phenyl sulfide compound and anhydrous ethanol is 8.5 g / 100 mL;

[0142] An aminophenyl sulfide compound, bismaleimide-diethylene glycol, and isopropyl alcohol were mixed, a catalyst was added, and the mixture was heated to 88°C and refluxed for 36 hours. 1-Propanethiol-2-dimethoxysilane was added and the reaction was continued for 16 hours. The mixture was then distilled under reduced pressure, washed, and dried to obtain hydrosilane. The mass ratio of the aminophenyl sulfide compound, bismaleimide-diethylene glycol, and 1-Propanethiol-2-dimethoxysilane was 1:1.77:0.66. The catalyst was BF3·OEt2, the amount of which was 6.5% of the mass of the aminophenyl sulfide. The ratio of the aminophenyl sulfide compound to isopropyl alcohol was 5 g / 100 mL.

[0143] Diallyl episulfide resin, hydrosilane, and toluene were mixed, heated to 50°C, and a platinum catalyst was added; the temperature was raised to 75°C and the reaction was kept constant for 120 minutes to obtain an organosiliconized episulfide resin; the molar ratio of the allyl double bond in the diallyl episulfide resin to the silicon-hydrogen bond in the hydrosilane was 1:1.2; the platinum catalyst was a chloroplatinic acid / isopropanol solution, and the amount of chloroplatinic acid was 1 / 2100 of the amount of the allyl double bond; the ratio of the diallyl episulfide resin to toluene was 80g / 100mL;

[0144] Steps (1, 4) are the same as (1, 3) in Example 1, except that the epoxy resin is replaced by an organosiliconized episulfide resin to obtain a sealant.

[0145] Comparative Example 1: A method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant, comprising the following steps:

[0146] (3) Diallyl bisphenol A epoxy resin, hydrosilane, and toluene were mixed, heated to 30° C., and a platinum catalyst was added; the temperature was raised to 70° C. and the reaction was carried out at a constant temperature for 65 minutes to obtain an organosiliconized epoxy resin; the molar ratio of the allyl double bond to the silicon-hydrogen bond was 1:1.1; the platinum catalyst was a chloroplatinic acid / isopropanol solution, and the amount of chloroplatinic acid was 1 / 4200 of the amount of the allyl substance; the ratio of diallyl bisphenol A epoxy resin to toluene was 80 g / 100 mL; the preparation process of hydrosilane was the same as that in Example 5;

[0147] Steps (1-2, 4) are the same as (1-3) in Example 5, except that the epoxy resin is replaced with a siliconized epoxy resin to obtain a sealant.

[0148] Comparative Example 2: A method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant, comprising the following steps:

[0149] (3) mixing 1-propanethiol-2-dimethoxysilane, bismaleimide-dipropylene glycol and isopropanol, adding catalyst, heating to 80℃, refluxing for 12h; distilling under reduced pressure, washing, drying to obtain hydrosilane; the mass ratio of bismaleimide-dipropylene glycol and 1-propanethiol-2-dimethoxysilane is 1:0.74; the catalyst is BF3·OEt2, and the amount is 5.0% of the mass of bismaleimide-dipropylene glycol; the ratio of bismaleimide-dipropylene glycol and isopropanol is 10g / 100mL;

[0150] mixing diallyl bisphenol A type epoxy resin, hydrosilane and toluene, heating to 30℃, adding platinum catalyst; heating to 70℃, constant temperature reaction for 65min to obtain silicone-epoxy resin; the molar ratio of allyl double bond and silicon hydrogen bond is 1:1.1; the platinum catalyst is chloroplatinic acid / isopropanol solution, and the amount of chloroplatinic acid is 1 / 4200 of the molar amount of allyl; the ratio of diallyl bisphenol A type epoxy resin and toluene is 80g / 100mL;

[0151] Steps (1-2, 4) are the same as (1-3) in Example 5, and the epoxy resin is replaced by silicone-epoxy resin to obtain the sealant.

[0152] Comparative Example 3: A preparation method of a moisture-curable alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0153] (3) mixing diallyl bisphenol A type epoxy resin, trimethoxysilane and toluene, heating to 30℃, adding platinum catalyst; heating to 70℃, constant temperature reaction for 65min to obtain silicone-epoxy resin; the molar ratio of allyl double bond and silicon hydrogen bond is 1:1.1; the platinum catalyst is chloroplatinic acid / isopropanol solution, and the amount of chloroplatinic acid is 1 / 4200 of the molar amount of allyl; the ratio of diallyl bisphenol A type epoxy resin and toluene is 80g / 100mL;

[0154] Steps (1-2, 4) are the same as (1-3) in Example 5, and the epoxy resin is replaced by silicone-epoxy resin to obtain the sealant.

[0155] Comparative Example 4: A preparation method of a moisture-curable alkoxysilane-terminated polyacrylate sealant, comprising the following processes:

[0156] (1) mixing polyether polyol and isocyanate silane (5.0% of the mass of polyether polyol), heating to 55℃, adding 0.51 parts of organotin catalyst, mixing, and reacting for 4h; discharging to obtain alkoxysilane-terminated polyether;

[0157] Step (2) is the same as (3) in Example 1, and the alkoxysilane-terminated polyacrylate is replaced by alkoxysilane-terminated polyether to obtain the sealant.

[0158] Experiment: Take the alkoxysilane-terminated polyacrylates in Examples 1-4, 6-7 and the alkoxysilane-terminated polyether in Comparative Example 4 as samples, and measure their viscosities at 25°C;

[0159] The sample was uniformly mixed with N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane (mass ratio of 100:3), and cured for one week in humid air at 25°C and 90RH% to prepare a gel. The surface drying time (test reference GB / T13447.5 finger touch method), Shore A hardness (test reference GB / T531.1), tensile strength (dumbbell-shaped specimen, test reference GB / T528, tensile rate 500mm / min) and cure depth (tested using a curing speed plate) of the gel were tested.

[0160] Table 1. Performance data of alkoxysilane-terminated polyacrylate:

[0161]

[0162] The sealants obtained in Examples 1-7 and Comparative Examples 1-4 were degassed and pressed onto the surface of an aluminum sheet, and then cured and maintained in humid air at 25°C and 90 RH% for 14 days before testing.

[0163] Peel strength test: GB / T 2790 is used as the reference standard, and an electronic tensile machine is used to test the 180° peel strength of the sample;

[0164] Water resistance test: Place the sample in a 50℃ constant temperature water bath and soak for 7 days. Take it out and wipe it dry with filter paper. Test the peel strength of the sample and calculate its water immersion reduction rate.

[0165] High and low temperature resistance test: Place the sample in a high and low temperature test chamber for a high and low temperature cycle test, with 20 / ℃ 30min→50 / ℃ 30min→20 / ℃ 30min→50 / ℃ 30min→20 / ℃ 30min as one cycle. Test the peel strength of the sample after four cycles and calculate its high and low temperature cycle drop rate;

[0166] Tensile performance test: GB / T 528 was used as the reference standard. Dumbbell-shaped specimens were used to test their tensile properties. The tensile speed was 50 mm / min and the test temperature was 25°C.

[0167] Table 2, sealant performance data:

[0168] Peeling strength (N / mm) Water immersion reduction rate (%) High-low temperature cycle reduction rate (%) Tensile strength (MPa) Example 1 15.4 20.2 26.7 3.2 Example 2 18.2 21.6 28.8 3.9 Example 3 16.5 23.9 29.6 4.3 Example 4 17.8 19.3 27.0 3.0 Example 5 21.9 14.4 21.1 5.1 Example 6 24.5 12.9 18.5 5.4 Example 7 26.3 10.7 15.2 5.8 Comparative Example 1 19.2 16.4 23.7 4.7 Comparative Example 2 17.8 17.0 24.9 4.3 Comparative Example 3 16.3 18.2 26.0 3.7 Comparative Example 4 14.0 27.4 42.3 2.5

[0169] According to the data in Table 1, the following conclusions can be clearly obtained: the alkoxysilane-terminated polyacrylate in Examples 1-4 and 6-7, the alkoxysilane-terminated polyether in Comparative Example 4 are compared, and the test results show that, compared with Comparative Example 4, the alkoxysilane-terminated polyacrylate in the examples has good performance data. This fully shows that the application improves the processability and mechanical properties of the sealant component silane-terminated polyether resin (alkoxysilane-terminated polyacrylate).

[0170] According to the data in Table 2, the following conclusions can be clearly obtained: the sealant obtained in Examples 1-7 is compared with the sealant obtained in Comparative Examples 1-4, and the test results show that: compared with Examples 1-4, the epoxy resin in Examples 5-7 is modified by silicone, and the obtained sealant has higher peel strength and mechanical properties, and still maintains good peel strength after immersion in water and high-low temperature cycle. This fully shows that the application improves the mechanical properties, water resistance and high-low temperature resistance of the prepared sealant, so as to have more excellent durable use ability.

[0171] Compared with Example 5, the organosiliconated episulfide resin in Comparative Example 1 is replaced by organosiliconated epoxy resin; its reactivity is relatively low, and under the influence of long chain structure, the crosslinking degree of the sealant system decreases, so that the performance data of the sealant decreases. In Comparative Example 2, the organosiliconated episulfide resin is replaced by organosiliconated epoxy resin, and the hydrogen silane is prepared from 1-propanethiol-2-dimethoxysilane and bismaleimide-dipropylene glycol; the sealant system does not introduce phenyl sulfide segment, so that the water resistance decreases, the sensitivity to high and low temperature increases, and the mechanical properties decrease to some extent. In Comparative Example 3, the organosiliconated episulfide resin is replaced by organosiliconated epoxy resin prepared from diallyl bisphenol A type epoxy resin and trimethoxysilane. Compared with Example 1, the water resistance is improved, but compared with Example 5, the long chain is not provided, so that the water resistance decreases greatly, and the mechanical properties also deteriorate. Compared with Example 1, the alkoxysilane-terminated polyacrylate in Comparative Example 4 is replaced by alkoxysilane-terminated polyether, and the mechanical properties and peel strength decrease. It can be seen that the setting of the sealant component and its preparation process in the application can comprehensively improve the mechanical properties, water resistance and high-low temperature resistance, and improve the service life.

[0172] It is apparent for those skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments, and the application can be implemented in other specific forms without departing from the spirit or essential characteristics of the application. Therefore, the embodiments should be considered as exemplary and non-limiting, and the scope of the application is defined by the appended claims rather than the foregoing description, and all changes falling within the meaning and range of equivalent elements of the claims are intended to be embraced in the application.

Claims

1. A process for the preparation of a moisture-curable alkoxysilane-terminated polyacrylate sealant, characterized in that: The process comprises the following steps: Step 1: mix the alkoxysilane-terminated polyacrylate and calcium carbonate, and heat; add a water-removing agent, and stir and mix to obtain a first mixture; Step 2: add aminosiloxane, an epoxy curing agent and an ultraviolet absorber to the first mixture obtained in Step 1, and stir under vacuum for 30-60 min to obtain a second mixture; Step 3: mix the second mixture obtained in Step 2, epoxy siloxane, epoxy resin, toughening agent, filler, catalyst and co-promoter under vacuum at 30-65℃ to obtain the sealant. The epoxy resin is a silicone-modified episulfide resin, which is prepared by the following process: Mix diallyl episulfide resin, hydrosilane and toluene, heat to 30-50℃, and add platinum catalyst; heat to 70-75℃, and keep the temperature constant for 65-120 min to obtain the silicone-modified episulfide resin.

2. The method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant according to claim 1, characterized in that: The sealant comprises the following components by mass: 100 parts of alkoxysilane-terminated polyacrylate, 50-200 parts of calcium carbonate, 3-10 parts of water-removing agent, 0.2-3.0 parts of aminosiloxane, 18-40 parts of epoxy curing agent, 0.1-1.0 parts of ultraviolet absorber, 0.2-3.0 parts of epoxy siloxane, 50-100 parts of epoxy resin, 20-30 parts of toughening agent, 20-75 parts of filler, 0.1-1.0 parts of catalyst and 1.0-2.5 parts of co-promoter.

3. The method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant according to claim 1, wherein: The alkoxysilane-terminated polyacrylate is prepared by the following process: mix acrylic resin, isocyanate silane and organotin catalyst at 40-50℃, and react for 3-6 h to obtain the alkoxysilane-terminated polyacrylate.

4. The method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant according to claim 1, wherein: The alkoxysilane-terminated polyacrylate is prepared by the following process: Mix acrylic resin, organic polyisocyanate and 83-91% of organotin catalyst by mass at 40-50℃, and react for 3-6 h; heat to 60-70℃, then add isocyanate silane and the remaining organotin catalyst, and continue to react for 2-3 h to obtain the alkoxysilane-terminated polyacrylate.

5. The method of preparing a moisture curing alkoxysilane terminated polyacrylate sealant according to claim 3 or 4, characterized in that: The acrylic resin is prepared by the following process: Mix butyl acrylate, methyl methacrylate, hydroxyethyl acrylate, mercaptoethanol and 80-90% of initiator by mass to obtain a mixed solution; Slowly add the mixed solution to polyether polyol, and add completely in 3-5 h; after the addition, keep the temperature constant for 1-2 h; add the remaining initiator, and continue to react for 1-2 h to obtain the acrylic resin.

6. The method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant according to claim 5, characterized in that: The acrylic resin comprises the following components by mass: 1000 parts of polyether polyol and 100-200 parts of mixed solution; the mixed solution comprises the following components by mass: 600-800 parts of butyl acrylate, 50-150 parts of methyl methacrylate, 10-20 parts of hydroxyethyl acrylate, 5.5-12.0 parts of initiator and 5-10 parts of mercaptoethanol.

7. The method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant according to claim 1, characterized in that: The alkoxysilane-terminated polyacrylate comprises the following components by mass: 1000-1200 parts of acrylic resin, 0-8 parts of organic polyisocyanate, 0.30-1.25 parts of organotin catalyst and 40-60 parts of isocyanate silane.

8. The method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant according to claim 1, characterized in that: The diallyl episulfide resin is prepared by the following process: Mixing 4,4'-diallyl bisphenol A, epichlorohydrin and tetramethyl ammonium bromide, under the protection of nitrogen atmosphere, heating to 90-100℃ for 100-150min; cooling to 80-85℃, slowly adding sodium hydroxide solution, continue to react for 30-40min; distillation under reduced pressure, adding toluene, washing with water, adding sodium hydroxide solution, 80-90℃ for 100-150min, adjusting the pH of the system to neutral, washing with water, distillation, to obtain a diallyl bisphenol A type epoxy resin; Mixing deionized water, ethanol, adding diallyl bisphenol A type epoxy resin, 88-91% component mass of potassium thiocyanate, at 30-35℃ temperature for 60-90min; adding the rest of the potassium thiocyanate, continue to react for 150-200min, to obtain a diallyl ring sulfur resin.

9. The method for preparing a moisture-curing alkoxysilane-terminated polyacrylate sealant according to claim 1, characterized in that: The hydrosilane is prepared by the following process: Mixing dimercapto diphenyl ether compound and sodium hydroxide solution, heating to 38-43℃, adding 3,5-dichloronitrobenzene, refluxing for 5-6h, to obtain a phenyl sulfide compound; Mixing phenyl sulfide compound, palladium / carbon catalyst and anhydrous ethanol, heating to 70-75℃, slowly adding hydrazine hydrate, refluxing for 7-8h, to obtain an aminophenyl sulfide compound; Mixing aminophenyl sulfide compound, bismaleimide-dipolyethylene glycol and isopropyl alcohol, adding catalyst, heating to 83-88℃, refluxing for 12-36h; adding 1-propanethiol-2-dimethoxysilane, continue to react for 12-16h, to obtain a hydrosilane.

Images