In this work, an epoxy resin was modified by stiff multi-walled carbon nanotubes (MWCNTs) and soft n-butyl glycidyl ether (BGE) and the modified epoxy resins were employed as the matrices for improvement of the tensile performance of glass fiber reinforced composites. The results indicated that the simultaneous addition of MWCNTs and BGE led to the greatest enhancements in the composite strength and modulus, demonstrating that their simultaneous introduction yielded a synergistic effect on the matrix modification for the improvement of the tensile performance of the GF/epoxy composites. The scanning electron microscope observations showed that the modified epoxy resins were substantially coated on the surfaces of GFs while the un-modified matrix was lightly attached on the GFs. The enhancements in the composite tensile performance were attributed to two aspects of enhanced GF strength/modulus and improved interfacial adhesion for the modified matrix compared to the un-modified case. Composites Part A: Applied Science and Manufacturing, 2014 Low magnification (left) and high magnification (right) TEM micrographs of MWCNTs used in this study. Optical micrographs of glass fiber bundle reinforced composites based on four different matrices: (A) unmodified epoxy resin, (B) MWCNT modified epoxy resin, (C) BGE modified epoxy resin and (D) both MWCNT and BGE modified epoxy resin. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) Optical images of the glass fibers extracted from the plain woven fabrics: (a) one GF bundle and (b) one single GF. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) |