BLENDS OF PROLACTONE-POLY(DIMETHYLSILOXANE)-POLYCAPROLACTONE TRIBLOCKCOPOLYMER WITH POLY(VINYL CHLORIDE) - PREPARATION AND CHARACTERIZATION

Miscibility, thermal, mechanical, gas permeation, morphological and su rface properties of poly(vinyl chloride) (PVC) blends containing 1-10% triblock prolactone-poly(dimethylsiloxane)-polycaprolactone (PCL-PDMS -PCL) copolymer were investigated by using several techniques. Fourier transform infra-red analysis of blends reveal the existence of specif ic interactions via hydrogen bonding between the alpha-hydrogen of PVC and the carbonyl group of PCL in the triblock copolymer. This PCL-PDM S-PCL/PVC blend system exhibited a single glass transition according t o differential scanning calorimetry and dynamic mechanical thermal ana lysis results. Stress-strain results showed that PCL-PDMS-PCL triblock copolymer is a very effective plasticizer for PVC. Gas permeability o f the blends increased with the copolymer content. Morphological and s urface properties of the blend system were examined by scanning electr on microscopy and contact angle measurements. (C) 1997 Elsevier Scienc e Ltd.