Non-destructive modification of aramid fiber by building nanoscale-coating solution to enhance the interfacial adhesion properties of the fiber-reinforced composites

Abstract

The poor interfacial adhesion between the aramid fiber (AF) and the matrix limits the application of the final composites. In this study, a novel coating method was adopted to modify AF Through metallization/grafting reaction, the copolymer synthesized by the low-temperature poly-condensation of p-phenylenediamine (PPDA), 4,4′-diaminodiphenyl ether (ODA) and terephthaloyl dichloride (TPC), was added into the dimethyl sulfoxide/sodium hydride (DMSO/NaH) solution, and a nano AF solution was obtained. Then epoxy groups were introduced to the amide bond by grafting Epichlorohydrin (ECH). By further grafting on Poly (propylene glycol) bis (2-aminopropyl ether) (PEA), more functional groups were introduced, which could increase the polarity of the fiber and the interfacial adhesion of the composites. The results show that not only the interfacial shear strength (IFSS) and the flexural strength of the aramid-reinforced composites has a significant increase compared with the untreated fibers, but the modification still maintains the mechanical properties of the fiber, indicating that building nanoscale coating solution is a very effective method to achieve non-destructive modification to ehance its interfacial adhesion with epoxy resin.

A promising method for promoting interfacial adhesion of aramid/rubber composite using atmospheric pressure plasma surface modification

“…Based on the results of the pullout test, the pullout force between modified aramid fiber and rubber reached 147 N. The results show that the pullout force with this method is comparable with the level of a traditional resorcinolformaldehyde-latex dipping system (154 N) while using harmful resorcinol and formaldehyde was avoided Yin et al 55 Surface construction of ANF/CNT onto aramid fibers to enhance interfacial adhesion and provide real-time monitoring of deformation In this study, functional groups, such as hydroxyl and amino groups were introduced on the surface of aramid fiber by tannic acid and polyethyleneimine. Then, to prepare a surface-coated fiber, the modified aramid fiber was impregnated in the aramid nanofiber/carbon nanotube aqueous dispersion…”

A review of the emerging approaches for developing multi‐scale filler‐reinforced epoxy nanocomposites with enhanced impact performance

“…Epoxy composites reinforced with epichlorohydrin coating followed by poly(propylene glycol)bis (2-aminopropyl ether) coating para-aramid fibers showed 29% and 24% improvement in IFSS and flexural strength, respectively, over pristine para-aramid fiber reinforced epoxy composites. 158 A summary of additional literature on para-aramid fiber/epoxy nanocomposites is presented in Table 4. A comparison of tensile strength as a function of the paraaramid fiber concentration in a para-aramid fiber reinforced composite system is given in Figure 9.…”

“…[64, [158][159][160][161][162][163][164][165][166][167][168] 2 Matrix: epoxy reinforcements: para-aramid fibers and nano-fillers (graphene oxide, silicon carbide, carbon nanotubes, etc. )…”

“…Consequently, compatibilized para‐aramid fibers reinforced epoxy composites exhibited better mechanical performance. Epoxy composites reinforced with epichlorohydrin coating followed by poly(propylene glycol)bis(2‐aminopropyl ether) coating para‐aramid fibers showed 29% and 24% improvement in IFSS and flexural strength, respectively, over pristine para‐aramid fiber reinforced epoxy composites 158 …”

Secondary silane grafting on aramid fibers improves the interfacial bonding performance in textile composite materials

“…1 As a common choice of reinforcement material, aramid fibers (AFs) have been employed in many textile reinforced structural composites for advanced practical applications in aerospace, transportation, military sectors and many others. [2][3][4] However, the molecular structure on the surface of AFs consists of rigid straight chains lacking active functional groups. The inert and smooth surface of the fiber leads to weak interaction and low friction along the interface between the fiber and resin matrix.…”