Preparation, properties, and crosslinking studies on polyurethane elastomers

Abstract

Polyurethane elastomers were prepared from structurally distinct hydroxyterminated polybutadiene and polyether-ester based prepolymers with diisocyanates such as hexamethyl-enediisocyanate, toluenediisocyanate, and diphenylmethanediisocyanate by the one short polymerization process. The effect of crosslinking by polyfunctional alcohols such as castor oil, trimethylolpropane, and poly(vinyl alcohol) on mechanical properties is compared in case of hydroxyterminated polybutadiene based polyurethane systems. The effect of crosslinking by trimethylolpropane on the mechanical properties was quantitatively studied in all the prepolymers based polyurethane systems. Crosslinking was also induced in the polyurethanes by taking higher NCO/OH ratio (R value) and the observations on mechanical properties are compared with those prepared with trimethylolpropane crosslinking. The thermal degradation of the polymers was studied in an oxygen atmosphere and interpreted with respect to their structure. © 1989 The Society of Polymer Science, Japan.