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.