聚乳酸/无机填料复合材料结构与性能的研究

Study on Structure and Properties of PLA/Inorganic Filler Composites

采用密炼器熔融共混法,将聚乳酸(PLA)分别与碳酸钙(CaCO3)、蒙脱土(MMT)及滑石粉(Talc)共混制备成生物降解复合材料,研究了PLA/无机填料共混物的力学性能、断面微观结构及结晶性能。结果表明:CaCO3、MMT和Talc均降低了PLA的断裂伸长率;Talc和CaCO3对PLA的拉伸强度影响不大,MMT明显降低了PLA的拉伸强度;Talc和CaCO3相对MMT在PLA基体中的分散较均匀;CaCO3和MMT改善PLA结晶性能的效果不明显,而Talc大大提高了PLA的结晶性能使,PLA的结晶温度下降约20℃结,晶度提高近3%。

Biodegradable composite materials were prepared with poly（lactic acid） and calcium carbonate,montmorillonite and talc by means of melt blending method in a mixing device,and then the mechanical properties,fractured surfaces microstructure and crystal properties of the blends were investigated.The results indicate that： the elongation at break of poly（lactic acid） is decreased with the addition of calcium carbonate,montmorillonite and talc;the tensile strength has no obvious changes with the addition of talc and calcium carbonate,but has a obviously descent with the addition of montmorillonite.Compared with montmorillonite,talc and calcium carbonate disperse more evenly in poly（lactic acid） matrix.The addition of calcium carbonate and montmorillonite can＇t improve significantly the crystal properties of poly（lactic acid）,but talc can increase the crystal property.The crystallization temperature of poly（lactic acid） decreases by about 20℃ and the crystallinity of poly（lactic acid） increases by 3% with the addition of talc.