Ethylene Oxide → Urethane acrylate

Participants

Reaction Steps

Into a reaction vessel equipped with a stirrer were charged 3.0 parts of tolylene diisocyanate, 50.5 parts of a ring-opening copolymer from ethylene oxide and butene oxide, having a number average molecular weight of 4,000, and 0.01 part of 2,6-di-t-butyl-p-cresol, as a polymerization inhibitor. The mixture was cooled with ice to a temperature of below 10° C., while stirring. When the temperature was lower than 10° C., 0.04 part of dibutyltindilaurate was added and the mixture was stirred for 2 hours while controlling the temperature at 20°-30° C. Then, after the addition of 0.3 part of γ-mercaptopropyltrimethoxy silane, the mixture was stirred for a further one hour at 30°-40° C., whereupon 1.2 parts of hydroxyethyl acrylate was added. The mixture was stirred for 4 hours at 50°-60° C., until the amount of remaining isocyanate is 0.1% by weight or less. The liquid urethane acrylate obtained in this manner is hereinafter referred to as UA-1.

Provenance & Evidence