Promoting dispersion of graphene nanoplatelets in polyethylene and chlorinated polyethylene by Friedel–Crafts reaction

Graphene nanoplatelets (GNPs) are the stacks of multi-layered graphene sheets which can be incorporated with different polymers in order to gain outstanding performance in mechanical, thermal, electrical, optical and barrier properties. However, the strong van der Waals interactions between graphene sheets make GNPs tend to agglomerate in polymer matrix, resulting in the concentration of stresses. In this paper, GNPs were compounded with high density polyethylene (HDPE) and chlorinated polyethylene (CPE) in the presence of a Lewis acid catalyst (AlCl3). The macrocarbocations in polymer chains, initiated by Friedel–Crafts reaction, formed strong interaction with delocalized conjugated π electrons of graphene sheets, which benefited to unfolding the aggregations of GNPs and improving its dispersion in the composites.