Solution blending preparation of polycarbonate/graphene composite: boosting the mechanical and electrical properties

Abstract

We report on the preparation of polycarbonate-based graphene (PC/G) composites, by using a simple and scalable solution blending method to disperse single-(SLG) and few-layer (FLG) graphene flakes, prepared by liquid phase exfoliation (LPE), in the polymer matrix. A solvent-exchange process is carried out to re-disperse the exfoliated SLG/FLG flakes in an environmentally friendly solvent, i.e. 1,3-dioxolane, which is also used to dissolve the polycarbonate pellets, thus facilitating the mixing of the polymer dispersion with the SLG/FLG flakes. The loading of SLG/FLG flakes improves the mechanical and thermal properties, as well as the electrical conductivity of the polymer, reaching a +26 % improvement of the elastic modulus at 1 wt% loading, and an electrical conductivity 10−3 S m −1 at 10 wt% with a percolation threshold achieved at 0.55 vol%. The as-prepared PC/G composite with the aforementioned reinforced properties can be a promising material for 3D printing-based applications.

A Review of the Synthesis and Applications of Polymer–Nanoclay Composites

“…The produced composites exhibited an enhanced and stable dielectric constant, which was attributed to the proper dispersion of graphite nanoplates in the PS matrix. Lago et al [63] improved the mechanical and electrical properties of polycarbonate-based graphene composites using a simple and scalable solution blending method. A solvent-exchange process was carried out to re-disperse the exfoliated graphene flakes in an environmentally friendly solvent (1,3-dioxolane).…”

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 .…”

Grafting polycarbonate onto graphene nanosheets: synthesis and characterization of high performance polycarbonate–graphene nanocomposites for ESD/EMI applications

“…28 Further, liquidphase-exfoliated single-and few-layer graphenes and PC were mixed in 1,3-dioxolane. 31 The Young's modulus of the nanocomposite obtained via solvent mixing was found to be enhanced up to 26% at a loading of 1.0 wt% with respect to that of pristine PC, and its electrical conductivity was found to be 10 À3 S m À1 at a loading of 10 wt%.…”

“…Pristine graphene with a high specic surface area irreversibly aggregates or restacks in PC matrixes because the van der Waals forces and p-p stacking interactions between graphene layers are much stronger than the interfacial interaction between graphene and PC. 11,26,27 Conventional melt 28,29 and solvent 30,31 mixing methods have been used to disperse graphenes in PC matrixes. For example, thermally reduced graphite oxides and PC melts were mixed in a twinscrew extruder at 280 C, and found to exhibit an 80% improvement in the Young's modulus and an electrical resistivity of 3.2 Â 10 3 U cm at a loading of 10 wt%.…”