Crystallization, mechanical properties, and controlled enzymatic degradation of biodegradable poly(epsilon-caprolactone)/multi-walled carbon nanotubes nanocomposites.
Crystallization, mechanical properties, and controlled enzymatic degradation of biodegradable poly(epsilon-caprolactone)/multi-walled carbon nanotubes nanocomposites.
复制标题
DOI：
10.1166/jnn.2011.4714
复制
发表时间：
2011-09
影响因子：
--
通讯作者：
Zhaobin Qiu;Huishan Wang;Changlin Xu
中科院分区：
文献类型：
--
作者：
Zhaobin Qiu;Huishan Wang;Changlin Xu
采用简单熔融共混法制备了可生物降解的聚己内酯(PCL)/多壁含羧基碳纳米管(f-MWNTs)纳米复合材料。扫描和透射电子显微镜观察表明，f-MWNTs均匀而细小地分布在PCL基质中。采用多种技术详细研究了低载量的f-MWNTs对PCL在纳米复合材料中的结晶、力学性能和受控酶降解的影响。实验结果表明，与纯PCL相比，f-MWNTs的加入提高了PCL/f-MWNTs纳米复合材料中PCL的非等温结晶峰温度和总等温结晶速率，而且少量的f-MWNTs的加入明显提高了PCL/MWNTs纳米复合材料的力学性能。对纯PCL和PCL/f-MWNTs纳米复合材料在低f-MWNTs负载量下的酶降解进行了详细的研究。失重率随酶解时间的变化、表面形貌的变化、膜厚的减小、膜表面f-MWNTs的出现以及酶降解后的相对分子质量几乎不变，表明PCL和PCL/f-MWNTs纳米复合材料的酶降解可能是通过表面侵蚀机理进行的。与纯PCL膜相比，f-MWNTs的存在降低了PCL基质在纳米复合材料中的酶降解速率。
Biodegradable poly(epsilon-caprolactone) (PCL)/multi-walled carbon nanotubes containing carboxylic groups (f-MWNTs) nanocomposites were prepared via simple melt compounding at low f-MWNTs loading in this work. Scanning and transmission electron microscopy observations indicate a homogeneous and fine distribution of f-MWNTs throughout the PCL matrix. The effect of low f-MWNTs loading on the crystallization, mechanical properties, and controlled enzymatic degradation of PCL in the nanocomposites were studied in detail with various techniques. The experimental results indicate that the incorporation of f-MWNTs enhances both the nonisothermal crystallization peak temperature and the overall isothermal crystallization rate of PCL in the PCL/f-MWNTs nanocomposites relative to neat PCL; moreover, the incorporation of a small quantity of f-MWNTs has improved apparently the mechanical properties of the PCL/MWNTs nanocomposites compared to neat PCL. The enzymatic degradation of neat PCL and the PCL/f-MWNTs nanocomposites at low f-MWNTs loading was studied in detail. The variation of weight loss with enzymatic degradation time, the surface morphology change, the reduced film thickness, the appearance of f-MWNTs on the surface of the films, and the almost unchanged molecular weight after enzymatic degradation suggest that the enzymatic degradation of neat PCL and the PCL/f-MWNTs nanocomposites may proceed via surface erosion mechanism. The presence of f-MWNTs reduces the enzymatic degradation rate of the PCL matrix in the nanocomposites compared with that of the pure PCL film.