The multiscale enhancement of mechanical properties of 3D MWK composites via poly(oxypropylene) diamines and GO nanoparticles

Abstract

AbstractInterfacial bonding between the fibers and matrix plays a large role in mechanical properties of composites. In this paper, poly(oxypropylene) diamines (D400) and graphene oxide (GO) nanoparticles were grafted on the desized 3D multi axial warp knitted (MWK) glass fiber (GF) fabrics. The surface morphology and functional groups of modified glass fibers were characterized by scanning electron microscopy (SEM) and fourier transform infrared spectra (FT-IR). Out-of-plane compression properties and the failure mechanisms of composites at different temperature were tested and analyzed. The results revealed that GO nanoparticles were successfully grafted on fibers under the synergistic effect of D400. In addition, D400-GO-grafted composite possessed the highest mechanical properties than desized composite and GO-grafted composite. Their strength and modulus were improved by 10.16%, 10.06%, 8.92%, 8.75%, 7.76% and 40.38%, 32.74%, 29.85%, 26.98%, 25.16% compared to those of desized composites at 30∘C, 60∘C, 90∘C, 120∘C, 150∘C, respectively. The damage to D400-GO-grafted composite was yarns fracture accompanied with fibers breakage, matrix cracking, interface debonding. At higher temperature, interlayer slipping with matrix plasticization was the main failure mode.