New prepolymers derived from polymeric MDI and polytetramethylene ether glycols.

摘要

The present invention is a prepolymer or quasi-prepolymer formed from the reaction of a given amount of a diisocyanate having at least 5 percent of polymethylene polyphenyl isocyanate and polytetramethylene ether glycols having a molecular weight between 150 and 3000. The glycol may be combined with other polyether or polyester glycols. The resulting NCO-terminated prepolymer or quasi polymer is a liquid which is stable at a temperature of 0 DEG C for at least 24 hours.