Preparation and Characterization of GNP/Nylon Composites

Abstract

Graphene nanoplatelets (GNP) and nylon (PA) have been often used as thermal filler and matrix and respectively to produce composites. In this work, PA6/PA66/GNP thermal composites were prepared via a melt blending method. Mechanical properties, morphology, and thermal properties of PA6/PA66/GNP composites were investigated. Because the GNP is very expensive, we investigated to use Al2O3 and graphite and examined the characteristics of the prepared composites. Thermal conductivity values of PA6/PA66/GNP composites remarkably increased with increase of GNP contents mainly via layered dispersion in nylon matrix. The thermal conductivity of composite containing 50 wt % of GNP was measured as 5.03 W·m–1·K–1 at 30 °C, indicating an increase of more than 15 times compared with that of the neat PA6. When the Al2O3 was replaced for GNP, the thermal conductivity of composites decreased, but the mechanical properties improved. When graphite was used to replace for GNP, thermal conductivity basically remained unchanged but mechanical properties decreased.

Review on recent progress in synthesis of graphene–polyamide nanocomposites

“…The flame-retardant properties of PA6 were significantly improved. Xu et al 46 developed PA6/PA66/GNP thermal composites by melt-blending method. The thermal conductivity of composite containing 50 wt% of GNP was measured as 5.03 W m –1 K –1 at 30°C, indicating an increase of more than 15 times compared with that of the neat PA6.…”

Carboxyl-functionalized graphene reinforced aromatic polyamide nanocomposites

“…Methods such as solvent blending and melt blending can provide uniform dispersion of graphene in PA. Zhang et al 25 prepared graphene/PA6 composites by melt processing and showed the effect of graphene nanofiller on crystalline temperature of PA6 was increased due to heterogeneous nucleation. Xu et al 26 produced PA6/PA66/GNP thermal composites by the melt-blending method with improved thermal properties of composite compared to the neat PA6. Roy et al 27 also improved the thermal stability of PA12/ polyethylenimine (PEI)-RGO composites by the melt-mixing process.…”