Polyolefine type poriisoshianeto constituent

摘要

PURPOSE:A polyurethane prepolymer (aliphatic polyisocyanate), prepared by reacting 1,8-diisocyanato-4-isocyanatomethyloctane with a bifunctional polyolefin- diol. CONSTITUTION:A polyurethane prepolymer of formula I, wherein R1, R2 and R3 are each -N=C=O or a group of formula II provided that at least one of them is a group of formula II, R4 and R5 are each -N=C=O or a group of formula III, Z is a trifunctional residue of formula IV, and Q is a residue derived by removing both of the terminal hydroxyl groups from a bifunctional polyolefin- diol. Said polyurethane prepolymer is a heat- or light-stable, nonyellowing aliphatic polyisocyanate, is freed from care for irritating odors and inhalation toxicity, is good in compatibility with a polyolefin resin, and is suitable as an isocyanate component of a two-component curing nonyellowing polyurethane resin or as the principal component of a one-component nonyellowing moisture- curable resin.