Dielectric, mechanical and transport properties of bisphenol A polycarbonate/graphene nanocomposites prepared by melt blending

Abstract

Nanocomposites based on polycarbonate (PC) and different amounts of untreated graphene nanoplatelets (GnP) (from 1 to 7 wt %) were prepared by melt blending. The nanocomposites were thoroughly characterized employing the following techniques: broad band dielectric spectroscopy, thermally stimulated depolarization currents, differential scanning calorimetry, tensile testing, dynamic mechanical thermal analysis, and water vapor, carbon dioxide and oxygen permeability measurements. The presence of a MWS relaxation mode indicated the accumulation of electrical charges trapped at the interfaces of the polycarbonate with graphene 2D platelets. The addition of GnP produced nanocomposite materials with enhanced mechanical and barrier properties. The melt mixed PC/graphene nanocomposites prepared here exhibit well-balanced properties, even though unmodified graphene nanoplatelets were used. In addition, the nanocomposites were obtained by a single extrusion process, which is easily scalable for industrial applications.

Free volume correlation with electrical conductivity of polycarbonate/reduced graphene oxide nanocomposites studied by positron annihilation lifetime spectroscopy

“…Among these conductive fillers, graphene has recently gained importance due to its high aspect ratio, small size, and excellent electrical conductivity . Different methods have been used to fabricate graphene filled PC composites (PC/G) including solution mixing, melt intercalation, and in situ exfoliation . Kim and Macosko prepared PC reinforced with functionalized graphene sheets using melt compounding, and the seven orders of magnitude increase in electrical conductivity was obtained .…”

“…Oyarzabal et al . prepared the PC/G nanocomposites by melt blending . Yoon and Jung startlingly grafted hydroxyl‐terminated PC onto methylene diphenyl diisocyanate‐functionalized graphene nanosheets .…”

A review on the mechanical, electrical and EMI shielding properties of carbon nanotubes and graphene reinforced polycarbonate nanocomposites

“…King et al obtained an increase in elastic modulus by 9% and 50% for PC/GNP nanocomposites prepared by melt blending with contents of 3 and 7 wt%, respectively. Oyarzabal et al prepared nanocomposites on the basis of PC and different amounts of untreated graphene nanoplatelets (GnP) (from 1 to 7 wt%) by melt blending. The PC/GnP composites with 7 wt% GnP loading showed 52% increase in elastic modulus as compared with neat PC.…”

Physicochemical properties of reduced graphite oxide conglomerated polyethylene nanocomposites

“…Previous studies have indicated that addition of carbonaceous nanomaterials such as graphite, graphene, graphene oxide and carbon nanotubes into thermoplastics improves the physicochemical properties of the polyolefins . Several techniques such as melt mixing process, in situ synthesis and solvent casting have been implemented to fabricate polyolefin nanocomposites with enhanced mechanical, thermal and diffusion properties compared with the neat polyolefins. The incorporation of graphene with polyolefins has been proven to increase the degree of crystallinity, which leads to an increase in ductility, rigidity and strength of the nanocomposites …”