DIELECTRIC AND THERMOANALYTICAL BEHAVIOR OF POLY(P-PHENYLENE SULFIDE)POLYMERS

Poly(p-phenylene sulfide) polymers, which are either highly linear or crosslinked, were investigated both dielectrically and thermoanalytica lly, in order to estimate how the structural differences affect the di electric and thermoanalytical behavior over a temperature range from r oom temperature to 300-degrees-C. It was found that the T(g) of the cr osslinked type is 3-degrees-C higher than that of the linear type acco rding to the DSC measurement, suggesting the slight lag in micro-Brown ian motion in the amorphous phase, while both polymers show similar pe rmittivity and dielectric dissipation factors in respect to frequency and temperature as well as global TSC spectra below T(g). Further, it became clear from the dielectric measurements from T(g) to 200-degrees -C that the linear type shows larger permittivity and dielectric dissi pation factor values above T(g) as compared with the crosslinked type, due to the Maxwell-Wagner-Sillars interfacial polarization. The linea r type shows a strong p peak at approximately 160-degrees-C in the glo bal TSC spectra, proposing the release of injected space charges trapp ed at the crystal/amorphous interfaces, while the crosslinked type one shows a weak p peak at approximately 190-degrees-C in the spectra, su ggesting a decrease of the interface effect due to crosslinking. Hence , the structural differences of PPS polymers have been demonstrated by using dielectric and thermoanalytical measurements.