EFFECTS OF ASPECT RATIO OF CARBON NANOTUBES ON CRYSTALLIZATION BEHAVIOR OF POLYLACTIDE IN ITS MULTIWALLED CARBON NANOTUBES COMPOSITES
Biodegradable polylactide (PLA) composites filled with acid-treated multiwalled carbon nanotubes (AMWNTs) with two obviously different aspect ratios (length to diameter) were prepared by coagulation method (see Fig. 1). A-MWNTs-S and A-MWNTs-L represent the low and high aspect ratio A-MWNTs, respectively. The percolation A-MWNTs concentrations for PLA/A-MWNTs-L and PLA/A-MWNTs-S composites are 2.5 and 4.0 wt%, respectively, which were determined by rheological method (see Fig. 2). Isothermal crystallization kinetics and morphology of neat PLA and its composites were further investigated to clarify the effects of aspect ratio and concentration of A-MWNTs on the crystallization behaviors of PLA in its composites. Results show that the different aspect ratio A-MWNTs exhibit substantially different effects on PLA crystallization. It is quite interesting to find that A-MWNTs-S promotes nucleation rate much more significantly than A-MWNTsL (see Fig. 3), which can be attributed to less sidewalls carboxyl on A-MWNTs-S surface and less entanglements of A-MWNTs-S man A-MWNTs-L. The sidewalls of A-MWNTs-S supply more nucleation sites than that of A-MWNTs-L at the same concentrations resulting in the faster crystallization rates for PLA/A-MWNTs-S composites (see Fig. 3).
Zhaohua Xu Heng Li Yanhua Niu Zhieane Wane
CAS Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Inst CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, Hefei Na
国际会议
PP’2010，Jinan International Symposium on Polymer Physics(2010济南国际高分子物理学术研讨会)
济南
英文
175-176
2010-06-06（万方平台首次上网日期，不代表论文的发表时间）