Induced Transcrystallization Behavior Of Poly(Phenylene Sulfide)in Static Non-fiber/Fiber System

Transcrystallinity(TC) is often occurred in fiber reinforced semi-crystalline polymer based composites.The mechanisms of forming transcrystallization of semi-crystalline polymer are still debated because the transcrystallization induced in complex environment.A new model that the transcrystallization induced in static non-fiber system is put forword for removing the mulriple factors which influnenced the transcrystallization. In the test of polarized optical microscope(POM), polymer’s interface must appear between the two glass slips, which can induce the transcrystallization. Meanwhile, the poly(phenylene sulfide)(PPS) is selected as the matrix in this project. The strength and crystallization behavior of matrix can be adhusted by controlling the thermal crosslinking of PPS under the same crystallization temperature. The internal curvature of polymer’s cylinder may be changed by means of adjusting the strength of PPS matrix,which can achieve the transcrystallization structure at the self-polymer interface. From the morphology studies, it has been found that the thickness of the transcrystalline layer decreases with the increases of thermal cross-linking temperature,the thickness of the transcrystalline layer decreases with the increases of thermal cross-linking time, the thickness of the transcrystalline layer decreases with the increases of crystallization temperature, the thickness of the transcrystalline layer decreases with the increases of cooling rate. The growth of transcrystalline layer is hindered by the spherulites nucleated in the bulk.The isothermal and non-isothermal crystallization behaviors of poly(phenylene sulfide)(PPS) are systematically investigated by differential scanning calorimetry(DSC). The results indicate that the thermal cross-linking temperature have an important impact on crystallization behaviors of PPS apparently. With the increasing of the thermal cross-linking temperature, the crystallization properties are promoted. It is attributed to the chemically cross-linking points and formation of network structures during the high thermal cross-linking temperature, which lead to increment of the effective nucleating sites. Meanwhile, kinetic analysis of crystal growth demonstrates that the regime transistions of PPS crystal growth, from regime III to regime II and from regime II to regime I, can be really observed at different thermal cross-linkingtemperature, respectively. The temperature of regime III/II and II/I transitions decrease with the growth of cross-linking temperature.