| 摘要 |
PURPOSE:To lower the viscosity, to make it possible to shorten the curing time, and to improve the electrical properties by reacting a specific polyether polyol with an aliphatic or alicyclic polyisocyanate, followed by a reaction with an acrylate compound. CONSTITUTION:A polyether polyol (A) of the given formula (wherein n and m are each 0 or more with n+m>=2) (e.g., a poly-1,2-butylene glycol) is reacted with an aliphatic or alicyclic polyisocyanate having a ratio of NCO/OH of 1.2-5.0 (e.g., isophorone diisocyanate), if necessary, in the presence of a reaction initiator (C) (e.g., dibutyltin dilaurate), thereby producing a prepolymer having NCO at its end. The obtained prepolymer is reacted with an acrylate compound (D) having a ratio of the NCO groups of the prepolymer to the OH groups of the component (D), NCO/OH ratio, of 1 or more and hydrogen active with an NCO group (e.g., 2-hydroxyethyl acrylate), thereby producing the title composition comprising a urethane-modified acrylate. |
