高导电、低逾渗PLA/CNTs导电复合材料的结构设计及性能研究  

Structural design and properties of PLA/CNTs conductive composites with high conductivity and low percolation

作　　者：孛海娃[1] 赵中国 王筹萱 薛嵘 BO Haiwa;ZHAO Zhongguo;WANG Chouxuan;XUE Rong(School of Materials Science and Engineering,Shaanxi University of Technology,Hanzhong 723000,China)

机构地区：[1]陕西理工大学材料科学与工程学院,陕西汉中723000

出　　处：《中国塑料》2024年第4期13-18,共6页China Plastics

基　　金：陕西理工大学博士人才启动项目(SLGRCQD2329)。

摘　　要：通过溶液吸附⁃熔融法制备了具有低逾渗高导电性能的左旋聚乳酸/右旋聚乳酸/碳纳米管(PLA/PDLA/CNTs)复合材料。在PLA/CNTs复合材料内部通过添加PDLA以提高复合材料的结晶性能,起到良好的体积排斥作用,促进了CNTs的分散,对PLA/PDLA/CNTs复合材料的导电网络结构进行有效调控;随着PDLA含量的增加,PLA/PDLA/CNTs复合材料的导电性能表现出了先增加后降低的趋势,当PDLA的含量仅为0.2%时,PLA/0.2%PDLA/0.6%CNTs的电导率从10^(-6) S/m提升到了10^(-4) S/m,提高了2个数量级,并且复合材料的导电逾渗值从0.58%(PLA/CNTs)降低到0.45%(PLA/PDLA/0.6%CNTs)。此外,CNTs和PDLA的引入可以有效的提高复合材料的结晶性能和复数黏度,相比于纯PLA,PLA/0.5%PDLA/0.6%CNTs的开始结晶温度(T_(o))和最大峰结晶温度(T_(p))分别提高了30.6℃和20.8℃。通过力学性能数据分析发现,在CNTs和PDLA的协同作用下,PLA/PDLA/CNTs复合材料的拉伸强度得到进一步的改善。因此,在PLA/CNTs复合材料中通过添加PDLA可以对导电网络结构进行有效调控的同时,改善其力学性能,为提升导电复合材料的综合性能提供了新方法。In this paper,PLA/PDLA/CNTs composites with low over diffusion and high conductivity were prepared by us⁃ing a solution adsorption⁃melting method.The PDLA component in the composites plays a good role of volume repulsion in promoting the dispersion of CNTs and enhancing the crystalline properties of PLA,thus effectively regulating the conductive network structure of the composites.The conductivity of the composites showed an increasing trend at first and then tended to decrease with an increasing in the PDLA content.The composite containing 0.2 wt%PDLA and 0.6 wt%CNTs ob⁃tained an increase in electrical conductivity from 10^(-6) to 10^(-4) S/m,which were improved by two orders of magnitude.Its conductive percolation value was reduced to 0.45 wt%compared to the PLA/CNTs composite(0.58 wt%).In addition,the introduction of CNTs and PDLA effectively improved the crystallization properties and complex viscosity of the compo⁃sites.The onset crystallization temperature and the maximum peak crystallization temperature of the composite with 0.5 wt%PDLA and 0.6 wt%CNTs increased by 30.6℃and 20.8℃,respectively,compared to those of pure PLA.The mechanical investigation indicated that the tensile strength of the composites was further improved as a result of the synergistic effect of CNTs and PDLA.Therefore,the conductive network structure could be effectively regulated through incorpo⁃rating PDLA into the PLA/CNTs composites,along with an improvement in the mechanical properties of the composites.This work provides a new method for improving the comprehensive performance of conductive composites.

关 键 词：聚乳酸 结晶性能 导电性能 力学性能 

分 类 号：TQ321[化学工程—合成树脂塑料工业]