INTERACTIONS IN POLYMER BLENDS BASED ON POLYESTERURETHANES INVESTIGATED BY THERMAL-ANALYSIS

TPU and chlorinated thermoplastic polyurethane (CTPU) were synthesized by using a two-step solution polymerization technique from poly(capro lactone) (CAPA), 4',4-diphenyl-methanediisocyanate (MDI) and 1,2-propa ndiol(PD) or 3-chloro-1,2-propandiol(CPD) for CTPU, respectively. TPU and CTPU were blended with styrene/acrylonitriles (SANs) with a differ ent amount of acrylonitrile within the entire compositional range. The blends were prepared as films from 15 wt% solution in dimethylformami de (DMF). The thermal properties of TPU, CTPU, SANs and their blends, as well as the influence of the amount of acrylonitrile (AN) component in SANs on the thermal behavior of blends, were studied by differenti al scanning calorimetry (DSC). The Flory-Huggins interaction parameter (chi(12)) was estimated.