多壁碳纳米管-聚乳酸复合材料的原位聚合制备及热性能和导电性能(英文)

Enhanced thermal and electrical properties of poly (D,L-lactide)/ multi-walled carbon nanotubes composites by in-situ polymerization

采用原位聚合的方法,制备了多壁碳纳米管聚乳酸复合材料。通过红外光谱、X射线衍射仪、差示扫描量热分析、热分析、扫描电镜和高阻计等对材料的结构性能进行分析。结果表明:多壁碳纳米管经混合酸处理,表面引入了有机基团,从而具有有机活性,与聚乳酸分子链之间的作用力加强,并可能存在部分聚乳酸分子链接枝于碳纳米管上;引入碳纳米管,使聚乳酸的玻璃化转变温度升高,但热降解温度降低。扫描电镜分析发现,多壁碳纳米管均匀分散于基体中,聚乳酸基体包覆在碳纳米管表面,界面作用增强。高阻计分析结果表明,随着碳纳米管含量的增加,材料的导电性能得到增强,从而克服了PLA材料本身存在的介电常数大、易带静电等不足。

Biodegradable poly （D,L-lactide） （PLA）/carboxyl-functionalized multi-walled carbon nanotubes （c-MWCNTs） composites were achieved via in-situ polymerization. These as-prepared composite materials were characterized with FT-IR, XRD, TG, DSC, SEM, and high insulation resistance meter. The results demonstrate that the multi-walled carbon nanotube was carboxyl functionalized, which improved the collection between c-MWCNTs and PLA, and further realized the graft copolymerization of c-MWCNTs and PLA. There is a higher glass transition temperature and a lower pyrolysis temperature of PLA/c-MWCNTs composites than pure PLA. The c-MWCNTs gave a better dispersion than unmodified MWCNTs in the PLA matrix, and an even coating of PLA on the surface of c-MWCNTs was obtained, which increased the interfacial interaction. High insulation resistance analysis showed that the addition of c-MWCNTs increased the electric conductivity, and c-MWCNTs performed against the large dielectric coefficient and electrostatic state of PLA. These results demonstrated that c-MWCNTs modified PLA composites were beneficial for potential application in the development of heat-resisting and conductivity plastic engineering.