▎ 摘　　要

NOVELTY - Pyrane functional group based ring-opening metathesis polymerization initiator i.e. 4-(pyren-1-yl)butyl bicyclo(2.2.1)hept-5-ene-2-carboxylate (I) is new. USE - (I) is useful in preparing graphene/polyionic liquid composite material for capacitors, photovoltaic devices, energy storage batteries and electrochemical sensors, and in antibacterial (all claimed). DETAILED DESCRIPTION - Pyrane functional group based ring-opening metathesis polymerization initiator i.e. 4-(pyren-1-yl)butyl bicyclo(2.2.1)hept-5-ene-2-carboxylate of formula (I) is new. INDEPENDENT CLAIMS are also included for: (1) preparing (I); and (2) preparation of graphene/polyionic liquid composite material, comprising dispersing (I) with graphene in a solvent for a period of time to obtain a initiator-modified graphene, then adding initiator-modified graphene as initiator and Grubbs second generation catalyst as catalyst into polyionic liquid monomer, and carrying out ring-opening metathesis polymerization to obtain final product.