Effect of polycarbonate structure and reduction time on graphene oxide dispersion

Abstract

Polycarbonate (PC)/graphene oxide (GO) composites with different GO reduction time and PC types were prepared by using a twin screw extruder at 260 °C after solution mixing with chloroform. The chemical reaction degree of PC/GO composites with GO reduction time was confirmed by C–H stretching peak at 3000 cm −1, and the chemical reaction degree decreased with GO reduction time. The slope for storage (G′) versus loss (G″) modulus plot decreases with an increase in heterogeneous property of the polymer melts. So we can check the GO dispersion of the PC/GO composites using by the slop for G′–G″ plot. According to the G′–G″ slopes for PC/GO composite with GO reduction time, GO was well dispersed within PC matrix when the reduction time decreased. It was re‐confirmed by atomic force microscope (AFM) results. Based on the degradation temperature by Thermogravimetric analysis, G′–G″ slopes, and surface roughness by AFM, the branched PC was better than linear PC for the GO dispersion within PC matrix. The fact was also confirmed by tensile test results that the Young's modulus increased with the improvement of GO dispersion. Copyright © 2015 John Wiley & Sons, Ltd.

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

“…They reported an increase in 23% at 7 wt % content. Several authors have obtained larger increments in modulus using thermally reduced graphite oxides (TrGO), in contrast with the nanocomposites obtained in this work, where no surface treatment is applied to the graphene.…”

“…The same complex preparation method (solution mixing followed by melt mixing) was also used by Lee et al . to prepare nanocomposites of linear (L‐PC) and branched (B‐PC) polycarbonates with thermally reduced graphene oxides.…”

Flow-Mediated Interaction between Graphene Oxide Nanosheets and Polycarbonate Chains

“…As an effective method to avoid restacking, blending the graphene oxide (GO) with polymers directly and inducing the in situ thermal reduction of GO within the polymer melt have attracted increasing attention. − It is because the dispersion of GO in composites can be greatly promoted due to the interaction between the oxygen-containing groups on the surface of GO and the polymeric matrix. − The in situ thermal reduction of GO nanosheets depends largely on the chemical properties of polymer matrixes. For example, Ye et al .…”

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

“…Currently, to the best of our knowledge, there is not reported any PC/graphene (PC/G) composite where LPE of natural graphite has been exploited, whereas primarily graphene derivatives such as GO or RGO have been previously used. 53,[71][72][73][74] In particular, for what concerns the solution blending approach, the solvents used for the dissolution of PC are chloroform 72 and THF, 71 both suspected of being carcinogenic substances. 75,76 In this work, we developed a simple solution blending process, to produce PC/G composite pellets using a 1,3-dioxolane-based dispersion, having a twofold function, acting as a dispersant for the graphene flakes and able to dissolve the PC for the realization of the final polymer composite.…”