Effect of carbon nanotube grafting on the wettability and average mechanical properties of carbon fiber/polymer multiscale composites

Abstract

An experimental investigation is performed to relate the wetting behavior of unsized and carbon nanotube (CNT) grafted carbon fibers to the average mechanical properties of unsized and CNT grafted carbon fiber/polymer multiscale composites. Contact angle measurements and single fiber pull out tests show that the choice of polymer matrix plays a crucial role in determining whether the incorporation of CNTs on the fiber surface enhances or degrades the wettability and hence average mechanical properties of carbon fiber/polymer composites. CNT grafting leads to a significant improvement in interfacial shear strength as well as flexural and tensile response of carbon fiber/polymer composites with the epoxy resin. However, incorporation of CNTs on fiber surface has no significant effect on the average mechanical properties of carbon fiber/polyester composites. Moreover, it is recorded that the relative enhancement in properties after CNT grafting depends on the fiber orientation in CNT grafted carbon fiber/epoxy composites. POLYM. COMPOS., 39:E1184–E1195, 2018. © 2018 Society of Plastics Engineers

Interfacial shear strength of carbon nanotubes based hybrid composites: effect of loading rate

“…Once the unsized fibers are coated with catalyst, they are subjected to the reactive environment of argon, hydrogen and acetylene gases inside a Chemical Vapour Deposition (CVD) reaction chamber (Technos Instruments, India) as per the procedure detailed in Ref. [14]. After the successful completion of a CVD cycle, the catalyst coated CFs gets transformed into CNT coated CFs.…”

“…Interfacial strength primarily depends on the area of contact available on the fiber surface to interact with the matrix [9] which can be increased by synthesizing CNTs on the surface of fiber [10,11]. Additionally, grafted nanotubes improve the wettability of fiber with matrix by increasing the surface energy of unsized carbon fiber [10] ultimately enhancing the ability of the fiber to attract the matrix [14] and spread it more efficiently. This leads to an improvement in stress transfer between fiber and matrix through an enhanced interfacial area, mechanical interlocking and localized stiffening of the matrix [8].…”

Single‐stage plasma‐chemical synthesis and characterization of carbon nanoparticle‐polymer suspensions

“…[ 1–3 ] The most common reason is poor wettability of carbon particles by the polymer, which leads to the agglomeration of these particles and their nonuniform distribution throughout the material. [ 4,5 ] The main approach to solve this problem is functionalizing the surface of carbon particles, for example, by chemical grafting of hydroxyl groups [ 6,7 ] or forming a shell on surfaces of the particles. [ 8–10 ] These procedures require the introduction of additional operations into the workflow for the pretreatment of filler particles.…”

“…[ 11,12 ] It was shown in our preliminary studies that it is possible to obtain a more uniform distribution of carbon particles in the polymer matrix, [ 11 ] compared with the conventional methods of their introduction. [ 4,5 ] The gas‐discharge technique forms a shell, for example, an oligomer or polymer on the particles' surface corresponding to the initial monomer. [ 11 ] Such a shell can enhance the adhesion of particles to the polymer matrix, and, as a result, significantly affects the mechanical characteristics of the polymer compositions.…”

Synergistic effect of nano‐SiO2 and small‐sized graphene oxide on carbon fiber/epoxy composite

“…Therefore, it is of great importance to improve interfacial structure in composites . There are many kinds of surface treatment methods by controlling and modifying interfacial properties to improve mechanical performance of CF composites, among which sizing of nano‐materials on fiber surface is an important method by improving interfacial adhesion and roughness . Nano‐materials coated on CF surface can improve mechanical interlocking and chemical bonding with matrix resins.…”