聚乳酸形状记忆发泡材料制备与形状记忆性能研究

Preparation and Shape Memory Properties of Polylactic Acid Shape Memory Foam

利用超临界CO;间歇性降压法,制备一系列不同微观结构的聚乳酸(PLA)发泡材料,并探究环境温度、保压压强对PLA发泡材料微观形貌、孔隙率、泡孔尺寸的影响,并分析PLA发泡材料的形状记忆性能。结果表明:制备的PLA发泡材料具有结构可调控、形状记忆性能良好等特点。当保压压强为17.24 MPa,环境温度为140℃,PLA发泡材料具有较大膨胀率,且泡孔形貌均匀,具有良好形状记忆性能。低于20℃的变形温度下,PLA发泡材料的形状记忆固定率与回复率较好,其形状记忆回复率达到90%以上。

A series of polylactic acid(PLA) foams with different microstructures were prepared by supercritical CO;intermittent depressurization. The effects of ambient temperature and holding pressure on the microstructure, porosity and pore size of PLA foaming materials were investigated, and the shape memory performance of PLA foaming materials were analyzed. The results show that the prepared PLA foam has the characteristics of controllable structure and good shape memory performance. When the holding pressure is 17.24 MPa and the ambient temperature is 140 ℃, PLA foam plastic has large expansion rate, uniform pore morphology and good shape memory performance. When the deformation temperature is lower than 20 ℃, the shape memory fixation rate and recovery rate of PLA foam are better, and the shape memory recovery rate is more than 90%.