Effect of Soft and Hard Segment Structures on Thermo-Mechanical Properties of Segmented Poly(ester-siloxane)urethanes

摘要

Various segmented poly(ester-siloxane)-urethanes containing hard and soft segntents, were prepared by melt polyaddition using a multistep procedure. Thus, soft sequences based on poly(ethylene glycol adipate)diol (PEGA) as ester components. a.ω- poly(dimethylsiloxane)diol (PDMS), were built. The hard segments were composed from 404- diphenylmethane diisocyanate (MDI). 2,4-tolylene diisocyanate (TDI) or hexamethylene diisocyanate (HDI). Dynamic mechanical analysis (DMA) and differential seanning calorimetry (DSC) (from other investigations) were employed to characterize segntented polyurthane materials. The obtained data revealed that the thermal curves are significantly influenced by the soft and hard segment structures in the temperature range studied.