Low residual monomer IPDI-PPG prepolymer

摘要

A prepolymer composition includes at least 70 wt. % of a 2:1 adduct of isophorone diisocyanate (IPDI) and polypropylene glycol (PPG), and includes less than 1 wt. % residual IPDI. A process for preparing the composition, includes reacting IPDI with polypropylene glycol at an NCO:OH ratio greater than 2:1 to provide a product mixture containing the 2:1 adduct, wherein residual IPDI is distilled from the product mixture such that a concentration of residual IPDI in the product mixture is less than 1%.