外消旋聚乳酸/多壁碳纳米管复合材料的制备及性能研究

Preparation and Properties of Poly(D,L-lactide)/ Multi-Walled Carbon Nanotubes Composites

采用溶液共混法制备了外消旋聚乳酸/多壁碳纳米管(PDLLA/MWNT-COOH)复合材料.分别采用差示扫描量热仪(DSC)、热重分析仪(TGA)、扫描电镜(SEM)对复合材料进行了表征,并借助纳米压痕测试系统和高阻计对复合材料进行了力学和电学性能测试.结果显示,复合材料的玻璃化温度都在53℃左右;热稳定性能随着碳纳米管的加入而提高;当碳纳米管的重量分数不高于5%时,其团聚现象比较轻微;弹性模量和硬度在碳纳米管重量分数为5%时达到最大值;体积电导率随碳纳米管含量的增加不断提高,当碳纳米管含量为7%时,复合材料的体积电导率较纯的PDLLA增加了8个数量级.

Poly（D,L-lactide）（PDLLA） with different components multi-walled carbon nanotubes（MWNT-COOH） composites were prepared by solution co-blending method.Differential scanning calorimeter（DSC）,thermo gravimetric analyzer（TGA）,scanning electron microscopy（SEM） were used to characterize the composites,the mechanical and electrical properties of the composites were measured using a nanoindentation system and High Resistance Meter,respectively.The results indicated that the glass temperatures of the composites were all about 53 ℃,the thermal stabilities were improved by the addition of the MWNT-COOH,and the agglomeration of MWNT-COOH was slight when its weight fraction was not more than 5%.Both the elastic modulus and hardness of the composites reached a maximum value when the weight fraction of MWNT-COOH was 5%.The volume electrical conductivities of the composites increased continuously with the increasing of MWNT-COOH,and it was almost 8 orders of magnitude improvement for composite with 7% MWNT-COOH compared with that of the pure PDLLA.