کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5201945 | 1502910 | 2014 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Enzyme-catalyzed degradation behavior of l-lactide/trimethylene carbonate/glycolide terpolymers and their composites with poly(l-lactide-co-glycolide) fibers
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Enzyme-catalyzed degradation behavior of l-lactide/trimethylene carbonate/glycolide terpolymers and their composites with poly(l-lactide-co-glycolide) fibers Enzyme-catalyzed degradation behavior of l-lactide/trimethylene carbonate/glycolide terpolymers and their composites with poly(l-lactide-co-glycolide) fibers](/preview/png/5201945.png)
چکیده انگلیسی
A series of high molar mass terpolymers is synthesized by ring-opening polymerization of l-lactide (LLA), 1, 3-trimethylene carbonate (TMC) and glycolide (GA). A totally bioresorbable composite is obtained by reinforcing a terpolymer matrix with plasma treated poly (l-lactide-co-glycolide) (PLGA) short fibers. Solution cast films of the various materials are allowed to degrade at 37 °C at pH 8.5 Tris buffer using proteinase K, in comparison with a PLLA-TMC copolymer and a PLLA homopolymer. Degradation is monitored by using various analytical techniques such as gravimetry, DSC, GPC, 1H NMR and SEM. The results show that the enzymatic degradation rate of PLLA-TMC-GA terpolymers with predominant LLA component is affected by both the average LLA block length (lLLA) and crystallinity. A shorter average LLA block length results in lower crystallinity, which will lead to faster degradation. However, too short average LLA block length (i.e. lLLA â¤4.0) can retard the degradation process. The composition of the copolymers remains unchanged during degradation. In contrast, the molar mass decreases due to hydrolytic chain cleavage in the bulk. Similarly, thermal property changes are observed with increase of the melting temperature and melting enthalpy in most cases. SEM observation strongly supports a surface erosion mechanism. The composite PLTG95/5/5C exhibits lower mass loss rate as compared to neat PLTG95/5/5 due to the presence of PLGA fibers which are non-degradable by proteinase K. On the other hand, the composite shows much faster molar mass loss rate than PLTG95/5/5 because the rapid hydrolytic degradation of PLGA fibers speeds up the degradation of the matrix by internal autocatalysis.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer Degradation and Stability - Volume 103, May 2014, Pages 26-34
Journal: Polymer Degradation and Stability - Volume 103, May 2014, Pages 26-34
نویسندگان
Jianting Dong, Lan Liao, Yan Ma, Li Shi, Gongxi Wang, Zhongyong Fan, Suming Li, Zhiqian Lu,