Synthesis of non-destructive amido group functionalized multi-walled carbon nanotubes and their application in antistatic and thermal conductive polyetherimide matrix nanocomposites

Abstract

Thermal conductive and antistatic polyetherimide (PEI) nanocomposites were fabricated by encapsulating non-destructive amido group functionalized multi-walled carbon nanotubes (MWCNTs) into the PEI matrix. Briefly, nearly half of acyl chloride groups in poly (acryloyl chloride) reacted with sodium azide and formed acyl azide groups, which could conjunct with MWCNTs via non-destruction nitrenes addition reaction. The remaining acyl chloride groups in poly (acryloyl chloride) hydrolyzed into carboxyl groups, therefore COOH-rich MWCNTs (MWCNTs@azide polyacrylic acid) were synthesized without serious damage to the MWCNTs. Then, MWCNTs@azide polyacrylic acid were then reacted with p-Phenylene diamine (PPD) and transformed to amido group functionalized MWCNTs (MWCNTs@PPD). MWCNTs@PPD could participate into the in situ polymerization of PEI matrix, where the conjunction between bisphenol A dianhydride and amido groups on MWCNTs@PPD guaranteed the strong covalent bonding at the PEI/MWCNTs interface, which directly avoided the aggregation of MWCNTs. Owing to the non-destructive modification of MWCNTs and tight matrix/filler interface, the volume electric and thermal conductivity of as-prepared nanocomposites was up to 6.4 × 10−8 S/cm (1.0 wt%, MWCNTs@PPD) and 0.43 W/(m · K) (4.0 wt%, MWCNTs@PPD), respectively. Copyright © 2016 John Wiley & Sons, Ltd.