RHEOLOGICAL PROPERTIES OF POLY(EPSILON-CAPROLACTONE) AND POLY(STYRENE-CO-ACRYLONITRILE) BLENDS

Rheological properties of poly(epsilon-caprolactone) (PCL) and Poly(styrene-co-acrylonitrile) (SAN) blends were examined as a function of the acrylonitrile (AN) content in SAN, to systematically understand the correlation between the interaction parameter and the rheological properties of miscible polymer blends. When the plateau modulus (G(N)0) and zero shear viscosity (eta-0) of the PCL/SAN blends are plotted against the AN content in SAN, a minimum is observed. Qualitatively, the results obtained parallel the variation of the interchain interaction with the AN content. The negative deviation of G(N)0 and eta-0, from linearity seems to be attributed to the increase in the entanglement molecular weight between dissimilar chains which results from the chain extension caused by interchain interaction.