Fabrication of polyamide 6/reduced graphene oxide nano-composites by conductive cellulose skeleton structure and its conductive behavior

Abstract

Benefited from hierarchical porous structure of Loofah sponge (LS) fibers, a 3D electrically and thermally conductive network structure termed conductive cellulose skeleton (Cellulose-RGO-TDI) was fabricated. In addition, PA6 molecular chains were covalently bonded with conductive cellulose skeleton by reaction between imino groups of PA6 and isocyanate groups of Cellulose-RGO-TDI. As a result, PA6/Cellulose-RGO-TDI nano-composite with high electrical and thermal conductivity was fabricated via reactive melt processing. Both RGO outside the fiber and RGO inside the 3D-bundled micro-channel work together to assemble omnibearing trans-scale conductive networks in the whole hierarchical porous structure of the cellulose skeleton. Finally, more integral conductive pathways are established by RGO along the cellulose fiber, which is more beneficial to transmission of charge carrier and phonons in the whole cellulose skeleton. Exfoliated RGO nano-sheets homogeneously dispersed between matrix and cellulose skeleton and a good interface forms, which promoted formation of electrically and thermally conductive network, resulting in the remarkably improved electrically conductivity of 5.8 × 10−1 S/m and thermally conductivity of 0.419 W m−1 K−1 of the composite with 1.2 vol% RGO loading.