Structural Evolution of Polyglycolide and Poly(glycolide-co-lactide) Fibers during the Heat-Setting Process
Structural Evolution of Polyglycolide and Poly(glycolide-co-lactide) Fibers during the Heat-Setting Process
复制标题
聚乙交酯和聚乙交酯-丙交酯纤维在热定形过程中的结构演变
DOI：
10.1021/acs.biomac.1c00449
复制
发表时间：
2021-07-02
影响因子：
6.2
通讯作者：
Wang, Zongbao
中科院分区：
文献类型：
--
作者：
Dong, Zhimin;Miao, Yushuang;Wang, Zongbao
PGA and P(GA-co-LA) fibers applied as surgical sutures strongly depend on their microstructure. The structural evolution in both the relaxed and tensioned states during heat-setting after hot stretching, which included heating and postannealing, was investigated using in situ WAXD/SAXS and DSC techniques. We found that the fibers of both PGA and P(GA-co-LA) with 8% LA content under the relaxed state were more advantageous than the fibers under the tensioned state indicated by the larger crystallite sizes and unit cell parameters and the higher crystallinity. The mechanical properties of the samples increased after heat-setting. Heat-setting at 120 degrees C was more suitable for promoting the fiber properties, which can be ascribed to crystal formation and perfection. During the heating, the thermal expansion increased the unit cell parameters and the long period of PGA linearly, whereas the unit cell parameters of P(GA-co-LA) had an obvious turning point at 60-80 degrees C, and the long period showed a sudden decline in the temperature range of 60-80 degrees C, which was mainly the result of the discharge of LA units. The unit cell parameters and the long period of both PGA and P(GA-co-LA) decreased during the isotherm process due to crystal perfection. However, the P(GA-co-LA) decrease was more prominent than PGA because of the inclusion of LA monomers in the crystal structure of GAs.
