Flow-Mediated Interaction between Graphene Oxide Nanosheets and Polycarbonate Chains

• Published in: Journal of physical chemistry. C 2021-02, Vol.125 (7), p.4146-4154
• Main Authors: Chen, Xiangfei, Xia, Lei, Huang, Yajiang, Lv, Yadong, Kong, Miqiu, Li, Guangxian
• Format: Article
• Language: English
• Subjects: C: Physical Properties of Materials and Interfaces
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.0c09218

Blending graphene oxide (GO) directly with polymers and then inducing the in situ reduction of GO is a promising method to alleviate the dilemma of dispersion. In this work, solution-mixed polycarbonate (PC)/GO composites were subjected to quiescent melt annealing and microextrusion, respectively, to reveal the effect of melt mixing conditions on the physicochemical structure of GO and the polymer/GO interactions. In both cases, the GO nanosheets experienced an in situ thermal reduction in the PC melt and a certain number of PC chains were bound tightly onto the surface of in situ thermally reduced GO (IrGO) nanosheets. For the melt-annealed samples without melt flow, PC chains were mainly adsorbed onto the surface of IrGO via π–π stacking and the number of attached chains increased with the elevation of temperature. For the microextruded samples, the presence of melt flow facilitated the transesterification reaction between the hydroxyl/carboxyl groups of GO and the carbonate groups of PC chains, although the number of adsorbed PC chains decreased slightly at high screw speeds. It is suggested that the melt mixing conditions, especially the melt flow, play a vital role in controlling the physicochemical structure of GO and in regulating the interaction between GO and polymer.