Preparation and characterization of functionalized graphene oxide/carbon fiber/epoxy nanocomposites

Abstract

a b s t r a c tGraphene oxide (GO) was functionalized using three different diamines, namely ethylenediamine (EDA), 4,4 0 -diaminodiphenyl sulfone (DDS) and p-phenylenediamine (PPD) to reinforce an epoxy adhesive, with the aim of improving the bonding strength of carbon fiber/epoxy composite. The chemical structure of the functionalized GO (FGO) nanosheets was characterized by elemental analysis, FT-IR and XRD. Hand lay-up, as a simple method, was applied for 3-ply composite fabrication. In the sample preparation, the fiber-to-resin ratio of 40:60 (w:w) and fiber orientations of 0 , 90 , and 0 were used. The GO and FGO nanoparticles were first dispersed in the epoxy resin, and then the GO and FGO reinforced epoxy (GO-or FGO-epoxy) were directly introduced into the carbon fiber layers to improve the mechanical properties. The GO and FGO contents varied in the range of 0.1e0.5 wt%. Results showed that the mechanical properties, in terms of tensile and flexural properties, were mainly dependent on the type of GO functionalization followed by the percentage of modified GO. As a result, both the tensile and flexural strengths are effectively enhanced by the FGOs addition. The tensile and flexural moduli are also increased by the FGO filling in the epoxy resin due to the excellent elastic modulus of FGO. The optimal FGO content for effectively improving the overall composite mechanical performance was found to be 0.3 wt%. Scanning electron microscopy (SEM) revealed that the failure mechanism of carbon fibers pulled out from the epoxy matrix contributed to the enhancement of the mechanical performance of the epoxy. These results show that diamine FGOs can strengthen the interfacial bonding between the carbon fibers and the epoxy adhesive.

Optimization of mechanical properties of polypropylene/talc/graphene composites using response surface methodology

“…Similar results have also been reported in previous studies. Ashori et al [24] investigated the effect of functionalized graphene oxide (FGO) on the properties of carbon fiber (CF)/epoxy composites and found that the FGO creates difficulties to pull out carbon fibers from the matrix. Their SEM micrographs showed that the addition of FGO miniaturized the gaps between the pulled-out carbon fibers and the epoxy matrix.…”

Using maleic anhydride functionalized graphene oxide for improving the interfacial properties of carbon fiber/BMI composites

“…The flexural The improvement of flexural strength should be attributed to the enhancement of the interfacial adhesion between the CFs and MAH-GO (or GO). The enhanced interfacial adhesion allows better load transfer from the resin matrix to the CFs [2,23]. Another possible reason is the synergistic effects [24] of microscopic CFs and nanoscale MAH-GO (or GO).…”

“…Carbon fiber (CF) reinforced polymer composites have been widely used in aerospace, automobiles, constructions and other industry fields because of their excellent mechanical properties, such as high specific strength, specific modulus and damping capacity [1][2][3]. As well known, the mechanical properties of fiber reinforced composites are largely dominated by the fiber-matrix interfacial adhesion.…”

“…[5][6][7][8]. Recently, the utility of graphene oxide (GO) or functionalized GO as additives to enhance the interfacial properties of CF reinforced polymer composites has begun to attract more attention [2,9]. Because the functionalized GO has various functional groups and large specific surface area, it can be uniformly dispersed and firmly adsorbed on the surface of CFs to prepare a new hierarchical reinforcement.…”

Effects of surfactants on the properties of epoxy/graphene nanocomposites

“…The strong van der Waals force makes graphene attracts each other, and thus induces the reaggregation of graphene. 19,20 To solve this problem, surface functionalization of graphene is commonly used. [21][22][23][24] Without forming actual chemical bonds, surfactant functionalization connects the graphene and functional groups by only physical adsorption, which involves the advantage of easy processability and high de-bundling effectiveness.…”