Intercalation Structure and Enhanced Thermal Oxidative\nStability of Polyamide 6/Graphene Nanocomposites Prepared through\nin Situ Polymerization

Abstract

Polyamide 6 (PA6)/graphene\noxide (GO) nanocomposites were prepared\nthrough the in situ polymerization method. GO layers were partially\nreduced, exfoliated by intercalation of PA6 molecules with a high\nintercalation ratio, and dispersed uniformly in the matrix without\nobvious aggregation. The crystalline form of PA6 transformed from\nthe γ-form to the α-form by addition of GO, and the network\nstructure centering on GO formed through the intermolecular interaction\nbetween the two phases. During the thermoaging process, compared with\npure PA6, the reduced viscosity and tensile strength of the composite\nremained at a high level, and the carbonyl index increased much more\nslowly. In addition, the degradation temperature increased, the degradation\nrate decreased, and the activation energy changed slightly, indicating\nthe enhanced thermal oxidative stability of PA6. With increasing GO\ncontent, the oxygen permeability coefficient decreased significantly,\nand the radical scavenging ratio increased, which was favorable for\ninhibiting the oxidative degradation of PA6 molecules.