Investigation on the isothermal crystallization of poly(phenlene sulfide) by rheology and polarized light microscopy

Multiwave frequency experiments were used to determine the critical gel behavior of the crystallizing melt of poly(phenylene sulfide) (PPS), which allowed for the simultaneous measurement of the viscoelastic properties at different oscillation frequencies. Therefore it was possible to determine the apparent critical gel point because of the shorter measuring time. The resulting critical gel time was related to the crystallization kinetics during the early stages. The isothermal crystallization kinetic of PPS was calculated by rheometer and hot stage-polarized light microscopy (PLM) experiments. The Avrami exponent n from PLM and rheological techniques was 2.9 and 2.7, therefore the two methods were around 3. The half crystallization time was 2025s for optical microscopy and 2112s for the rheological techniques, and were in good agreement with each other.