PLA/PTL/SiO2纳米离子复合材料的制备及形状记忆性能研究

摘要

为提高生物医用材料聚乳酸的形状记忆性能.文中采用熔融共聚合的方法合成丙交酯与三亚甲基碳酸酯的共聚物(PLT),利用纳米离子共混的方法将合成的共聚产物与聚乳酸(PLA)以及二氧化硅(SiO2)复合制备了聚乳酸纳米离子复合材料PLA/PLT/SiO2.采用差示扫描量热(DSC)、热重分析(TGA)及X-射线衍射(XRD)等方法对复合材料的性能进行了研究,采用动态热力学分析仪(DMA)研究了复合材料的形状记忆性能.研究结果表明:复合材料为结晶聚合物,具有良好的热稳定性.可形变记忆区间为33～53℃,在室温状态下材料保持其优良的力学性能.PLA/PLT/SiO2复合材料在拉伸率为150％时形状固定率均不小于88.9％,形状回复率大于87.5％,表现出良好的形状记忆性能.说明通过纳米离子复合的方法不仅改善了聚乳酸的热力学性能,也增强了聚乳酸的形状记忆性能.%The study aims to improve the shape memory performance of the biomedical material-polylactic acid.In this work,lactide and trimethylene carbonate copolymers(PLT)were synthesized by melt condensation.And PLA/PLT/SiO2composites were prepared by blending the copolymer with polylactic acid and silicon dioxide nanoparticles.The obtained composites were characterized by differential scanning calorimetry (DSC),thermogravimetric analysis (TGA)and X-ray diffraction (XRD),and their shape memory performance was studied with a dynamic thermodynamic analyzer (DMA).The results indicate that the obtained polylactide composites are crystalline polymer with good thermal stability.Their deformable memory temperature interval is between 33to 53℃,having excellent mechanical properties at room temperature.Their shape retention rate is 88.9％and the recovery rate is greater than 87.5％at a stretch of 150％,showing good shape memory performance.It is concluded that the modified method not only improves PLA's thermodynamic performance,but also enhances its shape memory property.