Thermal-mechanical properties of a graphitic-nanofibers reinforced epoxy.
We previously developed a series of reactive graphitic nanofibers (r-GNFs) reinforced epoxy (nano-epoxy) as composite matrices, which have shown good wetting and adhesion properties with continuous fiber. In this work, the thermal-mechanical properties of the nano-epoxy system containing EponTM Resin 828 and Epi-cure Curing Agent W were characterized. Results from three-point bending tests showed that the flexural strength and flexural modulus of this system with 0.30 wt% of reactive nanofibers were increased by 16%, and 21% respectively, over pure epoxy. Fracture toughness increased by ca. 40% for specimens with 0.50 wt% of r-GNFs. By dynamic mechanical analysis (DMA) test, specimens with 0.30 wt% of r-GNFs showed a significant increase in storage modulus E' (by ca. 122%) and loss modulus E" (by ca. 111%) with respect to that of pure epoxy. Also thermo-dilatometry analysis (TDA) was used to measure dimensional change of specimens as a function of temperature, and then, coefficients of thermal expansion (CTE) before and after glass transition temperature (Tg) were obtained. Results implied that nano-epoxy materials had good dimensional stability and reduced CTE values when compared to those of pure epoxy.
Salehi-Khojin
Amin
A
Department of Mechanical Engineering and Applied Mechanics, North Dakota State University, Fargo, ND 58105, USA.
Jana
Soumen
S
Zhong
Wei-Hong
WH
D004853:Epoxy Resins; D006108:Graphite; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology; D013314:Stress, Mechanical; D013499:Surface Properties; D013816:Thermodynamics
D004853:Epoxy Resins; D006108:Graphite