Dielectric relaxation study of poly(styrene-co-4-vinylbenzoic acid)/poly(ethyl methacrylate-co-4-vinylpyridine) blends

Summary

The α-relaxations, located in the neighborhood of glass-transition region (Tg), of a styrene-co-4-vinylbenzoic acid (PSVBA) random copolymer blended in several weight proportions with an ethyl methacrylate-co-4-vinylpyridine (PEMAVP) random copolymer have been investigated by dielectric spectroscopy in the temperature and frequency ranging from 25 to 180 °C and 0.1 to 100 kHz, respectively. The analysis of the obtained results shows that the dielectric spectra of the miscible blends, essentially dominated by the response of PEMAVP, are composition dependent becoming broader with its content. These observations are correlated with segmental dynamic heterogeneities and blend concentration fluctuations.