Functionalized graphene oxide as coupling agent for graphene nanoplatelet/epoxy composites

Abstract

AbstractThe interface design plays a crucial role in developing superior mechanical performance of graphene nanoplatelets (GnP)/epoxy composite. Here, graphene oxide (GO) was applied as the coupling agent, because of π‐π interaction it formed with GnP and its rich surface functional groups. GO‐GnP couple was prepared and further it was treated separately with two diamines with different chain length (p‐phenylenediamine [PPDA] and Jeffamine D2000) producing functionalized GO‐GnP couple (f‐(GO‐GnP)). The chemical bonds formed between the amine functional groups on GO surface and epoxy resin during the curing process providing strong sheet/matrix interfacial adhesion. GO‐GnP/f‐(GO‐GnP) filler with two different weight ratios between GO and GnP (1:10 and 1:50) used as the fillers for preparing epoxy based composite with 0.43 and 0.86 wt% filler loading. For the tensile modulus, PPDA‐f‐(GO‐GnP: 1:10) sample gave ~40% improvement under 0.43 wt%, while at 0.86 wt%, the reinforcing result raised up to ~60% for PPDA‐f‐(GO‐GnP:1:50) sample. GO‐GnP couple/functionalized GO‐GnP couple gave up to ~110% improvement in toughness compared to simply using GnP at 0.86 wt% filler loading.