ANNEALING EFFECTS ON THE DYNAMIC MECHANICAL-PROPERTIES OF AROMATIC POLYPHENYLENE SULFIDE FIBER REINFORCED COMPOSITE

Polyphenylene sulphide is one of the recently developed aromatic semi-crystalline thermoplastic materials which, unlike conventional thermoset composites, can be hot-worked repeatedly. However, for the same reason, the degree of crystallinity is affected. This paper reports on the effects of annealing temperature and time on the storage modulus and the damping factor, as measured by the loss factor obtained from a three-point bending dynamic mechanical analyzer. Results indicate that quenching decreased the dynamic modulus values, but increased the damping factor significantly. Subsequent annealing had the effect of increasing the modulus values, but reducing the damping factor. A sharp decrease in the damping factor occurred after a critical annealing time, with the critical annealing time increasing with decreasing annealing temperature. A lower annealing temperature process would be more likely to successfully produce materials with a specified degree of crystallinity.