In situ vacuum exfoliation plus microwave curing: A facile and green technique for preparing polymeric composites with very good dispersion based on expanded graphite

Functional polymeric composites based on expanded graphite (EG) have obtained wide attentions worldwide owing to their great potential in many fields. Poor dispersion is the main problem limiting the full exploitation of outstanding properties of these composites. To solve the problem, a facile and green method, named as in situ vacuum exfoliation plus microwave curing (VEMC) technique, is developed. The biggest merit of the VEMC process is that worm‐like EG particles are directly used to prepare composites, and no solvent or other chemical is needed, so the chemical structure and original advantages of exfoliatable fillers can be fully utilized in the composites. A series of composites based on EG particles and epoxy (EP) resin, coded as new‐EG/EP, were fabricated using the VEMC technique. Interestingly, worm‐like EG particles are found to be in situ exfoliated into nanosheets, and these sheets are well dispersed in the resin. Compared with the composites prepared using traditional processes, new‐EG/EP composites have much higher dielectric constants, demonstrating that the VEMC technique is efficient to prepare composites with good dispersion based on exfoliatable fillers. POLYM. COMPOS., 36:385–388, 2015. © 2014 Society of Plastics Engineers