In-situ polymerization and covalent modification on aramid fiber surface via direct fluorination for interfacial enhancement

One Surface Treatment, Multiple Possibilities: Broadening the Use-Potential of Para-Aramid Fibers with Mechanical Adhesion

“…For example, by increasing mechanical adhesion together with chemical interactions, Nasser et al [ 30 ] have been able to increase short beam strength of laser-induced graphene-coated aramid fabric by 70% in epoxy matrix. Lv et al [ 13 ] have achieved similar results with in-situ polymer grafting and carbon nanotubes on aramid in the epoxy matrix, but they concluded the increase in interfacial shear strength (IFSS) to be due to increased polarity rather than topography. However, by purely increasing mechanical adhesion with adsorbed aramid nanofibers, Nasser et al [ 27 ] have been able to increase short beam strength by 26% and IFSS by 70% in epoxy, which shows what the imminent potential mechanical adhesion has in terms of composite applications.…”

“…On the other hand, with a chemical surface treatment, reactive side groups are grafted to the fiber surface, which can react with the matrix material and create a strong covalent bond between the fiber and the matrix [ 9 , 10 ]. However, these methods are often suitable for only one type of matrix material [ 11 , 12 , 13 ], may lose their effectiveness rapidly during storage [ 7 ] and may drastically reduce the mechanical properties of the fibers [ 14 , 15 , 16 ]. Thus, new approaches are needed, and research is increasingly directed towards utilizing mechanical adhesion between fibers and matrix [ 17 ].…”

“…Mechanical adhesion or interlocking can be formed between the fiber and matrix, for example, by adding nanowires [ 18 , 19 , 20 ], nanoparticles [ 21 , 22 , 23 ], nanotubes [ 13 , 24 , 25 , 26 ], or nanofibers [ 27 , 28 , 29 ] to the fiber surface. These structures simultaneously increase the surface area and the surface roughness of the fiber.…”

Enhanced mechanical and tribological properties of Kevlar/PTFE‐phenolic composites by improving interfacial properties by aramid nanofibers

“…In recent studies, the methods of introducing nanomaterials (eg, MWCNTs, ZnO, and GO) onto the surface of PTFE and aramid fibers have been widely adopted to enhance the surface roughness and activity. [ 17–19 ] Zhang et al [ 20 ] proved that the tribological behaviors of Nomex/PTFE‐phenolic composites were obviously enhanced, which was mainly attributed to increasing surface roughness, reactive functional groups, and wettability by coating MWCNTs on fibers surface. Tu et al [ 21 ] reported that polyethyleneimine/graphene oxide (PEI/GO) was noncovalently grafted onto the poly(p‐phenylene terephthalamide) (PPTA) fibers by the LbL assembly method, in which the poly‐dopamine was used as the “bridge” between PPTA fibers and PEI/GO multilayer films.…”

Surface Structured Polymer Blend Fibers and Their Application in Fiber Reinforced Composite

“…However, disadvantages including weak interfacial adhesion between fibers and matrix, smooth surface, and low modulus of elasticity all need to be improved to meet the application of fibers in extreme conditions. Thus, lots of works have focused on using oxidative, plasma polymerization, gamma radiation, polymer grafting methods to modify the fiber surface, aiming to increase the surface roughness, surface area, and interaction between fibers and matrix [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ]. These methods still need to solve environmental and process problems.…”