碳纳米管和立构复合晶对聚乳酸/碳纳米管复合材料结构和性能调控

摘要通过溶液-熔融共混的方法制备了不同导电填料含量的多壁碳纳米管(MWCNT)/立构复合晶(SC)/聚乳酸(PLA)导电复合材料,借助差式扫描热量仪(DSC)、热台偏光显微镜(POM)和自组装电阻仪详细地研究了MWCNT/SC/PLA导电复合材料的结晶性能与导电性能的关系。结果表明,通过溶液-机械共混的方式制备的MWCNT/PLA导电复合材料具有较低的导电填料逾渗阀值,约为0.6%,并且随着高熔点SC的引入,导电性能先提高后稳定。MWCNT的加入够显著提高复合材料的起始结晶温度、热力学分解温度和成核速度,而SC的加入增加了聚乳酸基体的球晶尺寸,抑制了成核效应,并表现出显著的晶体排斥效应。通过温度-电阻测试发现,在不同的热处理温度(T_s=60、80、100、120℃)下,复合材料的电导率降低;而随着热处理温度的提高和SC的引入,电导率稳定区的出现时间逐渐缩短,从20 min缩短到了8 min,并且复合材料的结晶度也表现出了先增加后降低的现象,PLA+0.6%MWCNT的结晶度从15.7%(T_s=60℃)增加到了68.1%(T_s=100℃)。 Multiwalled carbon nanotube(MWCNTs)/stereocomplex crystallization(SC)/polylactic acid(PLA)conductive composites with different conductive filler contents were prepared by solution-melt blending method,and the relationship between crystallization and conductivity of MWCNTs/SC/PLA conductive composites was studied by differential scanning calorimeter(DSC),thermal polarizing microscope(POM)and self-assembled resistance meter.The results show that MWCNTs/PLA conductive composites prepared by solution-mechanical blending have a low percolation threshold of about 0.6%of conductive filler,and with the introduction of vertical composite crystal(SC),the conductivity first increases and then becomes stabilized.The addition of MWCNTs significantly increases the initial crystallization temperature,thermodynamic decomposition temperature and nucleation velocity of the composite material,while the addition of vertical composite crystals(SC)increases the spherulite size of the polylactic acid matrix,inhibites the nucleation effect,and shows significant crystal rejection effect.It is found by temperature-resistance test that the conductivity of composites decreases at different heat treatment temperatures(T_s=60,80,100 and 120℃).With the increase of heat treatment temperature and the introduction of SC,the appearance time of the conductivity stability zone is gradually shortened from 20 min to 8 min,and the crystallinity of the composite material also increases firstly and then decreases,the crystallinity(PLA+0.6%MWCNTs)increases from 15.7%(T_s=60℃)to 68.1%(T_s=100℃).

作者贾旭妙刘欣月刘少飞王权张鑫赵中国陈立贵 JIA Xu-miao;LIU Xin-yue;LIU Shao-fei;WANG Quan;ZHANG Xin;ZHAO Zhong-guo;CHEN Li-gui(National and Local Engineering Laboratory for Slag Comprehensive Utilization and Environment Technology,School of Materials Science and Engineering,Shaanxi University of Technology,Hanzhong 723000,China)

机构地区陕西理工大学材料科学与工程学院

出处《塑料工业》 CAS CSCD 北大核心 2021年第4期54-59,共6页 China Plastics Industry

基金大学生创新创业大赛国家级项目(S202010720010) 中国博士后面上资助项目(2020M673585XB)。

关键词多壁碳纳米管聚乳酸导电性能立构复合晶 Multiwalled Carbon Nanotube Polylactic Acid Conductivity Stereocomplex Crystallization

分类号 TB332 [一般工业技术—材料科学与工程]