Grafting of epoxy chains onto graphene oxide for epoxy composites with improved mechanical and thermal properties
作者：YJ Wan, LC Tang*, LX Gong, D Yan, YB Li, LB Wu, JX Jiang, GQ Lai
關鍵字：Epoxy, Graphene oxide, compoistes, Mechanical properteis, Thermal properties
論文來源：期刊
具體來源：Carbon
發表時間：2014年
Epoxy composites filled with both graphene oxide (GO) and diglycidyl
ether of bisphenol-A functionalized GO (DGEBA-f-GO) sheets were prepared at
different filler loading levels. The correlations between surface modification,
morphology, dispersion/exfoliation and interfacial interaction of sheets and
the corresponding mechanical and thermal properties of the composites were
systematically investigated. The
surface functionalization of DGEBA layer was found
to effectively improve the compatibility and dispersion of GO
sheets in epoxy matrix. The tensile test indicated that the DGEBA-f-GO/epoxy
composites
showed higher tensile modulus
and
strength than either the neat epoxy or the GO/epoxy composites. For epoxy composite with 0.25 wt% DGEBA-f-GO,
the tensile modulus and strength increased from 3.15±0.11 to 3.56±0.08 GPa (~13%) and 52.98±5.82
to 92.94±5.03 MPa (~75%),
respectively, compared to the neat epoxy resin. Furthermore, enhanced
quasi-static fracture toughness (
KIC) was measured in case of the surface functionalization.
The GO and DGEBA-f-GO at 0.25 wt% loading produced ~26% and ~41% improvements
in
KIC values of epoxy composites,
respectively. Fracture surface analysis
revealed improved interfacial interaction between DGEBA-f-GO and matrix. Moreover, increased glass
transition temperature and thermal stability of the DGEBA-f-GO/epoxy composites
were also observed in the dynamic mechanical properties and thermo-gravimetric
analysis compared to those of the
GO/epoxy composites.