Chu C C, Browning A
Department of Textiles and Apparel, Martha Van Rensselaer Hall, Cornell University, Ithaca, New York 14853-4401.
J Biomed Mater Res. 1988 Aug;22(8):699-712. doi: 10.1002/jbm.820220804.
The objective of this study is to alter the fiber morphology of a linear aliphatic polyester, polyglycolic acid, by annealing treatment and to examine the changes of its degradation properties. The annealing was done at 150 degrees C, 170 degrees C, and 190 degrees C, and the specimens were annealed in four different strained conditions, freely hung, 0, 1, and 10%. After annealing treatments, the specimens were subject to in vitro hydrolytic degradation by immersing them in phosphate-buffer solution of pH 7.4 at 37 degrees C for up to 28 days. The thermal properties and gross morphology of the specimens were obtained. It was found that annealing treatments resulted in initial higher levels of crystallinity, which, in turn, influenced the hydrolytic degradation of the fiber. Among all the annealing conditions, the freely hung specimens annealed at 190 degrees C exhibited the most pronounced annealing effect on hydrolytic degradation, and was consistent with the observed gross morphologic changes. The change in the characteristics of fiber structure (i.e., the return to the stage of less oriented conformation upon freely hung annealing) was thought to be the cause.
本研究的目的是通过退火处理改变线性脂肪族聚酯聚乙醇酸的纤维形态，并研究其降解性能的变化。退火在150℃、170℃和190℃下进行，试样在四种不同的应变条件下退火，即自由悬挂、0%、1%和10%。退火处理后，将试样浸入37℃、pH值为7.4的磷酸盐缓冲溶液中进行体外水解降解，长达28天。获得了试样的热性能和总体形态。结果发现，退火处理导致初始结晶度较高，这反过来又影响了纤维的水解降解。在所有退火条件中，190℃退火的自由悬挂试样对水解降解表现出最明显的退火效果，这与观察到的总体形态变化一致。纤维结构特征的变化（即自由悬挂退火时回到取向较低构象的阶段）被认为是原因。
