聚乙烯/马来酸酐接枝聚合物修饰多壁碳纳米管

摘要

Multiwalled carbon nanotubes (MWCNTs) were oxidized by an acid mixture (concentrated It,SO, :HNO3 = 3 :lv/v) to form carboxyl groups, which were then reacted with anhydride ethylene diamine by an ami-dation reaction to introduce amine end groups that were subsequently grafted to polyethylene/maleic anhydride copolymer (PE-g-MA) to increase the dispersion of the modified MWCNTs in a polyethylene (PE) matrix. The chemical modification of the MWCNTs was verified by FTK, XPS and Raman spectroscopy. The modified MWCNT/PE composites exhibited an electrical percolation threshold at 0.67 vol% MWCNTs. The volume resistivities of the modified MWCNT/PE composites decreased from 1016 to 105Ω· m with increasing MWCNT content from 0.1 to 1.2 vol%.%多壁碳纳米管( MWCNTs)与混酸(浓硫酸∶浓硝酸体积比为3∶1)和无水乙二胺进行酸化、胺化反应使MWCNTs表面产生羧基和氨基基团,进而与聚乙烯/马来酸酐接枝聚合物(PE-g-MA)发生开环反应制备PE-g-MWCNTs,以提高MWCNTs在聚乙烯基体中的分散性.采用红外光谱、X-射线光电子能谱(XPS)和拉曼光谱对MWCNTs的化学修饰进行定性表征.结果表明:当MWCNTs的体积分数为0.67％时,MWCNT/PE复合材料的体积电阻率发生渗流突变.MWCNTs的体积分数在0.1％ ～1.2％时,MWCNT/PE复合材料体积电阻率由1016Ω·m下降至105Ω·m.