Thermal Properties of Hyperbranched Polymer/HTPB-PU IPN

Hyperbranched polymer/HTPB-PU IPNs were prepared, when HTPB (hydroxyl-terminated polybutadiene) and IPDI (isophorone diisocyanate) were cured into polyurethane (HTPB-PU) at the existence of hyperbranched polymer. Differential scanning calorimetry (DSC) was adopted to study the influence of hyperbranched polymer on thermal properties of HTPB-PU, while IPNs were formed. The result shows that the existance of hyperbranched polymer makes glass transition temperature of HTPB-PU reduces by around 2°C and that HTPB-PU lowers the melting point of hyperbranched polymer. Hyperbranched polymer plays a role of internal plasticization on HTPB-PU, and HTPB-PU influences crystallization of hyperbranched polymer in return.