聚苯硫醚及其纤维增强复合材料的等温结晶形态

采用热台偏光显微镜技术观察了聚苯硫醚(PPS)及其玻璃纤维、 炭纤维及芳纶纤维增强复合材料等温结晶过程中球晶结构形态的变化。研究了等温结晶温度对PPS的晶体形态及球晶生长速率的影响。结果表明, 结晶温度对PPS的结晶影响非常明显。在235~265℃, 随着等温结晶温度的升高, 聚苯硫醚球晶形态发生了从细小而具有部分束状结构到大而完善再到细小而不完善的变化过程, 球晶的生长速率随着结晶温度的增大呈非线性下降。而纤维的存在使PPS的结晶形态发生了从球晶结构到横穿晶的变化, 且不同纤维诱导形成横穿晶的程度有所不同。其中玻璃纤维和芳纶纤维可以诱导形成较为明显的横穿晶形态, 而炭纤维则不能诱导形成明显的横穿晶。 

Morphologies of isothermal crystallized pure poly and fiber-reinforced poly composites

The morphologies of pure poly (phenylene sulfide) (PPS) and glass, carbon, aramid fiber-reinforced poly (phenylene sulfide) composites crystallized isothermally from the melt were investigated by a polarized light microscope equipped with a hot-stage in real time. The spherulite growth rates of PPS were measured in the range of crystallization temperature from 235℃ to 265℃ as a function of crystallization time. The results show that the crystal growth rate decreases as the isothermal crystallization temperature increases, and the crystalline morphology of pure PPS varies from fine spherulite with sheaflike structure in part to bigger and perfect spherulite and then to fine and imperfect spherulite. The presence of fibers plays an important role in the morphologies of PPS which transformed from spherulite structure to the transcrystallization. And to what degree the transcrystallization induced depends on the kinds of the fibers. Among these fibers, glass fibers and aramid fibers possess the ability for inducing the transcrystallization of PPS while carbon fibers can not induce PPS to form the transcrystallization obviously.