EFFECTS OF FIBERS ON THE CRYSTALLIZATION OF POLY(PHENYLENE SULFIDE)

The isothermal crystallization of unreinforced poly(phenylene sulfide) (PPS) and PPS filled with glass, carbon, and aramid fibers was studied by differential scanning calorimetry. The Avrami exponent and rate constant are reported, but the crystallization half‐times were used to compare the effects of different fibers on the rate of PPS crystallization. The aramid and carbon fibers decreased the crystallization half‐time with the aramid fiber having the most pronounced effect. The glass fibers affected the crystallization half‐time only at the higher crystallization temperatures. The aramid filled PPS exhibited anomalous degree of crystallinity behavior in that the degree of crystallinity passed through a minimum as a function of temperature. The other systems all exhibited increasing degree of crystallinity with increasing crystallization temperature. Finally, the Avrami plot for the aramid filled PPS is not linear, and the data are fitted better with two linear regions indicating that two types of crystallization processes may be present. Copyright © 1990 John Wiley & Sons, Inc.