Interfacial Microstructure and Properties of Carbon Fiber Composites Modified with Graphene Oxide

Abstract

The performance of carbon fiber-reinforced composites is dependent to a great extent on the properties of fiber-matrix interface. To improve the interfacial properties in carbon fiber/epoxy composites, we directly introduced graphene oxide (GO) sheets dispersed in the fiber sizing onto the surface of individual carbon fibers. The applied graphite oxide, which could be exfoliated to single-layer GO sheets, was verified by atomic force microscope (AFM). The surface topography of modified carbon fibers and the distribution of GO sheets in the interfacial region of carbon fibers were detected by scanning electron microscopy (SEM). The interfacial properties between carbon fiber and matrix were investigated by microbond test and three-point short beam shear test. The tensile properties of unidirectional (UD) composites were investigated in accordance with ASTM standards. The results of the tests reveal an improved interfacial and tensile properties in GO-modified carbon fiber composites. Furthermore, significant enhancement of interfacial shear strength (IFSS), interlaminar shear strength (ILSS), and tensile properties was achieved in the composites when only 5 wt % of GO sheets introduced in the fiber sizing. This means that an alternative method for improving the interfacial and tensile properties of carbon fiber composites by controlling the fiber-matrix interface was developed. Such multiscale reinforced composites show great potential with their improved mechanical performance to be likely applied in the aerospace and automotive industries.

Surface Modification of Carbon Fibres for Interface Improvement in Textile Composites

“…In order to exclude the possible effects of commercial sizing on the interfacial shear strength and to improve the uniformity of the porous Fig. 1 The methodology of in-situ growth of graphene-related coatings on the surface of carbon fibres carbon coating, the size on the fibre surface was removed using two different methods following the practice used by other researchers [2,11]. Using the first method, the carbon fibres were immersed into 65 wt% HNO 3 for 1.5 h. Another method allows the carbon fibres to be immersed in acetone solution for 48 h. After the removal of the size from the carbon fibre surface, the carbon fibres were fully immersed into the mixed solution mentioned above before drying the fibres in an oven at 80°C for 12 h. Then the samples were then transferred to the tube furnace with the protection of Ar/H 2 gas in a (95:5) ratio atmosphere.…”

“…Properties of fibre reinforced composites are affected by the interface between fibres and matrix [2]. Fibre-matrix interfacial adhesion is extremely important since carbon fibres have chemical inertness and poor wettability with most of the polymeric matrices [3].…”

“…Removal of commercial sizing can also improve the surface chemical reactivity, which is beneficial to the enhancement of the fibre/resin interface, and make the catalyst precursors and carbon sources locate on the carbon fibre easily [10]. Zhang et al have used acetone to treat the carbon fibre to remove the commercial size from the surface of the carbon fibre [2]. In the study by Li et al they used 65 wt% HNO 3 to remove the size and also to introduce some carboxyl groups on to the carbon fibre [11].…”

Effects of Graphene-Oxide-Modified Coating on the Properties of Carbon-Fiber-Reinforced Polypropylene Composites

“…Liu et al fabricated multiscale CFRTPs by directly dispersing carbon nanotube (CNT) in the CF sizing agent. The results of mechanical tests indicated that the CFRTPs with CNT modified sizing showed 115.4% and 27.0% increases in improved interlaminar shear strength (ILSS) and impact toughness, respectively [20].…”

Pitch-Based Carbon Fibre-Reinforced PEEK Composites: Optimization of Interphase Properties by Water-Based Treatments and Self-Assembly

“…Furthermore, to the best of our knowledge, there is a limited understanding about the fibre-matrix compatibilization and adhesion mechanisms in such high performance TP composites [7]. More precisely it is assumed that fibre-matrix interface is actually the key to improve CFRP composites [8]. Indeed, one of the challenges linked to these materials relate to the fibre-matrix interface compatibilization, adhesion promotion, ageing and improvement of damage tolerance.…”