有机蒙脱土对PLA/PBS共混物相结构及性能的影响

Effect of Organic Montmorillonite on Phase Structure and Properties of PLA/PBS Blends

通过熔融共混的方法制备了聚乳酸/聚丁二酸丁二醇酯/有机蒙脱土(PLA/PBS/OMMT)复合材料,研究了OMMT对不同组成的PLA/PBS共混物微观结构的影响,进而研究其对热性能、热稳定性以及拉伸性能的影响。微观结构结果表明,添加OMMT到PLA/PBS共混物中,能够降低分散相的尺寸,均化分散相尺寸分布,使PLA/PBS(50/50)共混物的双连续相结构改变为海-岛结构。DSC结果表明,PBS能够提高PLA的结晶能力,添加OMMT后,PLA相的冷结晶温度和熔点明显提高,结晶度达到39.5%,PLA的结晶形貌更加完善。TG结果表明,PBS能够提高PLA/PBS共混物热稳定性,添加OMMT后,进一步提高了共混物的热稳定性,起始分解温度提高至307.3℃。添加OMMT后,PLA/PBS/OMMT复合材料的拉伸性能得到提高,PLA/PBS/OMMT(80/20/1)复合材料的拉伸强度和断裂伸长率分别达到53.9 MPa和34.2%,在保证材料强度的前提下,得到了较好的延展性。

Poly(lactic acid)/poly(butylene succinate)/organic montmorillonite(PLA/PBS/OMMT)blends were prepared by melt blending.The effect of OMMT on the microstructure of PLA/PBS blends with different compositions as well as thermal properties,thermal stability and tensile properties were studied.The microstructure results showed that addition of OMMT into the PLA/PBS blends could reduce the particle size and uniform size distribution of the dispersed phase significantly.In addition,bi-continuous phase structure of the PLA/PBS(50/50)blend was transformed into a sea-island structure after addition of OMMT.The DSC results showed that PBS could improve the crystallization ability of PLA.The crystallization temperature and melting point of the PLA phase were improved significantly by addition of OMMT.In addition,the crystallization of PLA reached up to 39.5%and the crystalline morphology of PLA was more perfect.The TG results showed that PBS could improve the thermal stability of PLA/PBS blends,and the addition of OMMT could further improve the thermal stability of the blends,resulting in higher The tensile properties of PLA/PBS/OMMT composite were improved by the addition of OMMT.The tensile strength and elongation at break of PLA/PBS/OMMT(80/20/1)composite were 53.9 MPa and 34.2%,respectively.It was achieved with better ductility under the premise of ensuring the strength.