摘要
在软硬段质量恒为5∶5,PEG分子量1000的PBT/PEG体系中添加一定摩尔含量的乳酸,合成了一系列PBT/PEG/LA嵌段共聚醚酯,其中乳酸占PBT硬段摩尔分数的0-30%。采用FT-IR,1^H-NMR,DSC等方法表征了材料的结构,并测试了力学性能及降解性能。主链硬段和热学性质分析表明,随着乳酸占原PBT/PEG共聚物中PBT摩尔分数的百分比由0增加至30%时,PBT摩尔分数从83.70%下降至58.58%,硬段熔点（Tm,h）也从196.3℃下降至170.1℃。力学性能测试表明,较高的LA摩尔含量有利于纤维降解,但使其断裂强度有所下降。PBT/PEG/LA纤维的可降解性能主要取决于其主链结构、聚集态以及LA的摩尔含量,降解后纤维的断裂强度保留率Y（%）与降解时间t（week）的关系满足回归方程：Y=A＋B1×t＋B2×t^2＋B3×t^3＋B4×t^4,相关系数R^2〉0.997。
A series of PBT/PEG/LA block copoly（ether-ester） with the constant mass ratio （r = 1 ） of soft to hard segment of PBT/PEG （Mn= 1000） and LA molar fraction to PET hard segment varying from 0 -30% were synthesized and characterized by means of intrinsic viscosity [ η], FF - IR, 1^H - NMR, DSC, mechanical properties and degradation behavior. The analysis on the hard segments in the copolymer chain and the thermodynamic properties showed that the molar faction of PBT decreased from 83.70% to 58.58% and the melting points （Tm.h） of hard segments decreased from 193.6 ℃ to 170.1 ℃ ,with the increase of LA molar ratio from 0 to 30% to the molar faction of PBT in the initial PBT/PEG copolymer. The mechanical properties testing showed that the higher molar fraction of LA impacts degradation of fibers, while the lower one improves the tensile strength. The biodegradable properties of PBT/PEG/LA fibers are related to its chain structure, collective structure and the molar faction of LA. The regression equation based on the correlations between the remaining percent of tensile strength Y（ % ） of degradable fi bers and time of degradation t（week） is Y =A ＋ B1 × t ＋ B2 × t^2 ＋ B3 × t^3 ＋ B4 × t^4, and the coefficient of determi nation R^2 〉 0.997.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2007年第5期92-96,共5页
Journal of Sichuan University (Engineering Science Edition)
基金
成都市科学计划资助项目(200538121)
