Dynamic-mechanical and differential scanning calorimetry measurements on crosslinked poly(ester-siloxane)-urethanes

Various crosslinked poly(ester-siloxane)-urethanes containing hard and soft segments, were prepared by a one-step melting/polyaddition. Thus, soft sequences based on poly(ethylene glycol adipate)diol (PEGA) or poly(diethylene glycol adipate)diol (PDEGA) as ester components, α,ω-poly(dimethylsiloxane)diol (PDMS) and/or polybutadienediol (PBD), were built. The hard segments were composed from diglycerin maleate tetrol (DGMA) and two aromatic diisocyanates, 4,4′-diphenylmethane diisocyanate (MDI) and 2,4-tolylene diisocyanate (TDI). Dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) were employed to characterise crosslinked polyurethane materials. The obtained data revealed that the thermal curves are influenced significantly by the soft and hard segment structures in the temperature range studied.