摘要
本研究通过溶液-熔融共混的方法制备了不同导电填料含量的聚丙烯/碳纳米管(PP/MWCNTs)导电复合材料,通过DSC、SEM和自组装电阻仪详细地研究了PP/MWCNTs导电复合材料的结晶性能与导电性能的关系及其在外场作用下的响应行为。通过溶液-机械共混方式制备的PP/MWCNTs导电复合材料具有较低的导电填料逾渗阈值,约为2.1%(质量分数,下同),并且随着导电填料含量的增加,聚丙烯的导电性能、热力学稳定性和结晶性能显著提高,热力学分解温度从410.1℃提高到了435.2℃。通过分析PP/MWCNTs导电复合材料在单次循环的温度-电阻响应的数据发现,PP/MWCNTs导电复合材料在25~180℃内一直表现为正温度效应(PTC),且最大和最小电阻值基本上未发生明显变化,具有较好的单调性。在多次温度循环实验(25~145℃)过程中,复合材料的电阻率表现出良好的重复性和稳定性。此外,对恒温-电阻响应行为数据进行分析发现,导电网络随时间的变化出现破坏与重组的现象,晶体排斥效应起到了主要作用。随着恒温温度的升高,导电网络的重组时间逐渐延长,从大约5 min延长到了15 min。
In this paper,PP/MWCNTs conductive composites with different contents of conductive fillers were prepared through melt blending.The relationship between temperature and conductivity were studied in detail by DSC,SEM and resistance meter.PP/MWCNTs conductive composites prepared by solution-mechanical blending had a low percolation threshold of about 2.1 wt%,and with the increase of conductive filler,the thermodynamic stability and crystallization properties of polypropylene were significantly improved,and the thermodynamic decomposition temperature increased from 410.1℃to 435.2℃.The analysis of temperature-resistance behavior of PP/MWCNTs conductive composites in single process temperature found that the conductive composites of PP/MWCNTs exhibited PTC effect in the temperature range from 25℃to 180℃,and the maximum and minimum resistance values basically did not change,showing good monotonicity.The temperature-resistance behavior of PP/MWCNTs conductive composites exhibited good repeatability and stability in the cyclic process temperature between 25℃and 145℃.In addition,in the analysis of resistance change at different heat treatment temperatures,it is found that the conductive network is destroyed and recombined with time going,and the crystal repulsion effect is also discerned.With the increase of the heat treatment temperature,the recombination time of the conductive network increases gradually,from about 5 min to 15 min.
作者
赵中国
贾旭妙
程少华
王渺
梁攀旭
李万顺
贾仕奎
ZHAO Zhongguo;JIA Xumiao;CHENG Shaohua;WANG Miao;LIANG Panxu;LI Wanshun;JIA Shikui(National and Loal Engineering Laboratory for Slag Comprehensive Utilization and Environment Technology,School of Materials Science and Engineering,Shaanxi University of Technology,Hanzhong 723000,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2021年第8期191-195,共5页
Materials Reports
基金
陕西省教育厅基金(20JK0564)
陕西理工大学人才启动基金(SLGRCQ2001)。
关键词
多壁碳纳米管
聚丙烯
导电复合材料
温敏行为
导电网络
MWCNTs
polypropylene
conductive composites
temperature-resistance behavior
conductive network
