以异山梨醇(IS)和碳酸二苯酯(DPC)为主要原料,利用熔融酯交换法合成了异山梨醇型聚碳酸酯(PIC)。考察了原料摩尔比、缩聚温度、预聚温度、预聚压力、催化剂种类及用量对PIC特性黏度的影响,并对其外观、结构、热性能和分子质量进行了测...以异山梨醇(IS)和碳酸二苯酯(DPC)为主要原料,利用熔融酯交换法合成了异山梨醇型聚碳酸酯(PIC)。考察了原料摩尔比、缩聚温度、预聚温度、预聚压力、催化剂种类及用量对PIC特性黏度的影响,并对其外观、结构、热性能和分子质量进行了测试。较优的合成工艺条件为:乙酰丙酮锂为催化剂,用量为13.5×10-4mol/(mol IS),DPC和IS的摩尔比为1∶1,缩聚温度为210℃,预聚温度为110℃,预聚压力为0.04 MPa。在该条件下所得PIC的特性黏度为46.72 m L/g,数均分子质量为1.98×104,色差为3.89,玻璃化转变温度(Tg)为144℃。展开更多
Bisphenol-A polycarbonate/dioctyl phthalate blend samples crystallized at a hydrostatic pressure were investigated by WAXD,DSC and SEM measurements.Some novel stereo-open spherulitic structures,i.e.,peony-,cabbage-,se...Bisphenol-A polycarbonate/dioctyl phthalate blend samples crystallized at a hydrostatic pressure were investigated by WAXD,DSC and SEM measurements.Some novel stereo-open spherulitic structures,i.e.,peony-,cabbage-,seaweed-,and lotus-like spherulites,were observed which belong to a three-dimensional structure and were only composed of crystalline region.The foleded-chain lamellar crystal was proved to be the sub-structure of these spherulites.This study also suggests a new route to grow such crystals so as to promote the understanding of the formation process and mechanism of polymer spherulites.展开更多
文摘以异山梨醇(IS)和碳酸二苯酯(DPC)为主要原料,利用熔融酯交换法合成了异山梨醇型聚碳酸酯(PIC)。考察了原料摩尔比、缩聚温度、预聚温度、预聚压力、催化剂种类及用量对PIC特性黏度的影响,并对其外观、结构、热性能和分子质量进行了测试。较优的合成工艺条件为:乙酰丙酮锂为催化剂,用量为13.5×10-4mol/(mol IS),DPC和IS的摩尔比为1∶1,缩聚温度为210℃,预聚温度为110℃,预聚压力为0.04 MPa。在该条件下所得PIC的特性黏度为46.72 m L/g,数均分子质量为1.98×104,色差为3.89,玻璃化转变温度(Tg)为144℃。
文摘Bisphenol-A polycarbonate/dioctyl phthalate blend samples crystallized at a hydrostatic pressure were investigated by WAXD,DSC and SEM measurements.Some novel stereo-open spherulitic structures,i.e.,peony-,cabbage-,seaweed-,and lotus-like spherulites,were observed which belong to a three-dimensional structure and were only composed of crystalline region.The foleded-chain lamellar crystal was proved to be the sub-structure of these spherulites.This study also suggests a new route to grow such crystals so as to promote the understanding of the formation process and mechanism of polymer spherulites.
