**2.2 ERFG particle synthesis**

ERFG particles were synthesized using the same experimental procedure as in our earlier published work [28, 30], and is presented in **Figure 2**. Briefly, fluorographite was dispersed and solvent exfoliated in TETA, then the C-F bonds on the fluorographite were substituted with amine groups from TETA at high temperature under argon gas protection, thereby producing amine-reacted fluorographene (ARFG). The ARFG particles were recovered from the TETA via filtration, washed, and then dispersed into epoxy resin (EPON 826), to synthesize epoxy-monomerreacted fluorographene (ERFG).

## **2.3 CFRP fabrication**

The formulation was prepared by a two-step procedure. Firstly, ERFG particles were added into an epoxy resin by centrifugal mixing. Immediately before use for CFRP fabrication, the epoxy resin containing ERFG particles was mixed with a hardener. The optimum weight ratio between the epoxy/ERFG mixture to the hardener was determined by a dynamic DSC screening for the maximum curing enthalpy. The CFRP panels were fabricated according to literature [31]. Next, the formulation consisting of epoxy with ERFG particles and hardener was spread onto each layer of CF fabric. After piling and spreading, accessories like the vacuum bagging were added. The impregnated CF fabrics were cured at room temperature for 5 hr. under vacuum, and then post-cured at 100°C for another 5 hr. The cured CFRP was removed from vacuum and bagging and was then cut into specific shapes according to ASTM D3039 by a water-cooled diamond saw for tensile testing.

#### **2.4 Characterization**

The chemical functionalization of the particles was characterized by an ATR FT-IR (Perkin Elmer). The morphology of the ERFG particles was imaged by a TEM (Jeol 1200).

The mechanical properties of CFRP were measured according to ASTM 3039 using a universal tester (AGS-X, Shimadzu). The through-plane thermal conductivity was measured as per ASTM D7984 using a thermal conductivity analyzer (TCi, C-Therm). Hydrogen permeability tests were performed by a professional testing lab (Versaperm Ltd.) in accordance with ASTM G148.

*Mechanically Improved and Multifunctional CFRP Enabled by Resins with High Concentrations… DOI: http://dx.doi.org/10.5772/intechopen.100141*
