Sealant of silane-terminated polymer and preparation method thereof

Abstract

The invention discloses a sealant of a silane-terminated polymer and a preparation method thereof. The sealant comprises the following main components by mass: 25%-55% of a silane-terminated polymer, 0.5%-10% of a catalytic silane coupling agent, 0.1%-1% of a self-polymeric silane coupling agent, 5%-40% of a plasticizer, 10%-60% of a filling material, 0.1%-2.5% of an ultraviolet absorber, 0.1%-2.5% of a hindered amine ultraviolet stabilizer, and 0.01%-0.5% of an organotin catalyst. The method specifically consists of: (1) adding high molecular weight and low-unsaturation polyether polyol, an isocyanate compound, and an organotin catalyst into a stirring tank in order at room temperature, and heating the mixture to a temperature of 40DEG C-60DEG C, then conducting heat preservation till isocyanate content in the mixture stabilized; (2) then adding an active group methyldimethoxysilane as an end capping agent, continuing preserving heat for reaction till the isocyanate content becomes 0, thus obtaining a silane-terminated polymer; (3) adding the above silane-terminated polymer, the catalytic silane coupling agent, the self-polymeric silane coupling agent, the plasticizer, the filling material, the ultraviolet absorber, and the hindered amine ultraviolet stabilizer into the stirring tank, carrying out blending for 30-45min under vacuum protection, thus obtaining the sealant of a silane-terminated polymer.

Description

Technical field [0001] The invention relates to a sealant and its preparation, in particular to a silane-terminated polymer sealant and a preparation method. Background technique [0002] At present, the sealants used in various industrial fields mainly include polyurethane, silicone, and polysulfide. The silicone sealant has good weather resistance, but its strength is slightly lower and the surface cannot be sprayed, which greatly limits its application range; Polysulfide sealant due to the pollution problem in the preparation process of the raw material polysulfide polysulfide rubber, the odor problem of the sealant, and the poor weather resistance of the polysulfide sealant, its use opportunities are becoming less and less, but it is the hollow glass field and the integral fuel tank sealing of the aircraft. Aspects are still in use. At present, polyurethane sealant is the most widely used industrial and construction assembly sealant, but polyurethane also has the problems of...

AI Technical Summary

Problems solved by technology

Although MS polymers have excellent overall performance, they are slightly inferior in terms of media resistance. At the same time, the preparation process of polymers is relatively complicated and the cost is high. Therefore, in recent years, silane-terminated polymers have been prepared by silane-terminated polyurethane prepolymers. technology has been greatly developed

[0004] Generally, silane-terminated polyurethane polymers are terminated by α or γ-secondary aminotrimethoxysilane, but the trimethoxysilane has high activity, is very easy to hydrolyze, and is easy to react with active groups in fillers or other additives, which affects the Storage stability of sealants based on such prepolymers

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