期刊
JOURNAL OF APPLIED POLYMER SCIENCE
卷 104, 期 2, 页码 831-841出版社
WILEY
DOI: 10.1002/app.25602
关键词
biodegradable polyesters; blends; degradation; enzymes; shear
Biodegradable polyester blends were prepared from poly(L-lactic acid) (PLLA) and poly(F-caprolactone) (PCL) (50/50) by melt-blending, and the effects of processing conditions (shear rate, time, and strain) of melt-blending on proteinase-K- and lipase-catalyzed enzymatic degradability were investigated using gravimetry, differential scanning calorimetry, and scanning electron microscopy. The proteinase-K-catalyzed degradation rate of the blend films increased and leveled off with increasing the shear rate, time, or strain for melt-blending, except for the shortest shear time of 60 s. The optimal processing conditions of melt-blending giving the maximum rate of lipase-catalyzed degradation were 9.6 x 10(2) s(-1) and 180 s, whereas a deviation from these conditions caused a reduction in lipase-catalyzed enzymatic degradation rate. At the highest shear rate of 2.2 x 10(3) s(-1), PCL-rich phase was continuous in the blend films, irrespective of the shear time (or shear strain), whereas PLLA-rich phase changed from dispersed to continuous by increasing the shear time (or shear strain). This study revealed that the biodegradability of PLLA/PCL blend materials can be manipulated by altering the processing conditions of melt-blending (shear rate, time, or strain) or the sizes and morphology of PLLA-rich and PCL-rich domains. The method reported in the present study can be utilized for controlling the biodegradability of other biodegradable polyester blends. (c) 2007 Wiley Periodicals, Inc.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据