変性ポリウレタンの物理特性

Abstract

The urethane linkage is kown to have low thermal stability whereas the isocyanurate ring has high thermal stability by reason of its irreversible reactivity at elevated temperature. Polyurethane elastomers containing isocyanurate cross-links have been produced with a wide range of modulus by means of triethylenediamine - high molecular epoxide catalyst combinations. This co-catalyst system appeared to promote the urethane reaction initially and, then, the trimerization in a second stage. Some of the formulations prepared by adding vinylacetate or acrylonitrile to the one-shot polymerization system have excellent dynamic mechanical properties at elevated temperature.