聚乳酸立构复合晶体的表面形貌及其力学性能-《郑州大学学报(工学版)》

文章信息/Info

Title:: The Morphology and Mechanical Properties of Poly(Lactic Acid) Stereocomplex Crystal

Author(s):: Liu Yanping Wei Hanghang; Li Qian; Zhengzhou university institute of mechanics and engineering science, henan zhengzhou 450001

Keywords:: Polylactic acid; Vertical structure composite crystals; The surface morphology; Mechanical properties of

摘要:: 采用溶液共混法制备了相同质量比的左旋聚乳酸(PLLA)和右旋聚乳酸(PDLA)的立构复合物。采用差示扫描量热仪、偏光显微镜、原子力显微镜、共聚焦显微镜和纳米压痕仪研究了聚乳酸立构复合物晶体的表面形貌及其力学性能的变化。结果表明，样品质量比为1:1时能够形成立构复合程度较高的立构复合晶体；晶体表面形貌出现比较明显的凹陷现象，这是由于结晶后分子链的收缩导致的；样品晶区的硬度和模量相比非晶区有所提升。

Abstract:: The surface morphology and the different mechanical properties between crystalline region and amorphous region of the stereocomplex crystal were studied in this paper. The same mass ratio of Poly (L-lactic acid) (PLLA) and poly (D-lactic acid) (PDLA) stereocomplex was prepared by solution blending. Differential Scanning Calorimetry, Polarizing Microscope, Atomic Force Microscopy, Confocal Laser Scanning Microscope and Nano Indentation Tester were used to list the surface morpholigy of PLA stereocomplex crystal and the diversification of mechanical properties. The result showed that a high degree of stereo-tacticity of PLLA/PDLA blend could be achieved from the mass ratio of 1/1 for sample.The research also showed that obviously depression phenomenon on the surface of crystal was formed due to the contraction of the molecular chain. Furthermore, the hardness and modulus of crystalline region were improved compared to the amorphous region.