Thermally induced time dependence of mechanical properties in biomedical grade polyurethanes.

摘要: The time dependence of the mechanical properties segmented urethanes as well urethane-urea systems were monitored after materials had been given a short thermal treatment followed by rapid cooling. Both linear and crosslinked studied but major focus was on many common biomedical grade urethanes. As noted in earlier studies nonmedical from this laboratory, also showed time-dependent changes that can be directly related to degree domain structure (microphase separation) may occur these copolymers. Interestingly, those possessing significant amounts urea linkage show little or no following treatment. effect chemical cross-linking influence formation process its stability. ramifications dependent effects have bearing biomaterial applications urethane polymers.