Interfacial properties and impact toughness of methylphenylsilicone resin composites by chemically grafting POSS and tetraethylenepentamine onto carbon fibers

• Published in: Composites. Part A, Applied science and manufacturing Vol. 84; pp. 1 - 8
• Main Authors: Wu, Guangshun, Ma, Lichun, Wang, Yuwei, Liu, Li, Huang, Yudong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2016
• Subjects: A. Carbon fibers; A. Polymer-matrix composites (PMCs); atomic force microscopy; B. Impact behavior; B. Interface/interphase; Carbon fiber reinforced plastics; carbon fibers; chemical bonding; composite materials; energy; epoxides; Fibers; Fourier transform infrared spectroscopy; Fourier transforms; Grafting; Impact strength; moieties; Polyhedral oligomeric silsesquioxane; Polymer matrix composites; Resins; shear strength; surface roughness; tensile strength; wettability; X-ray photoelectron spectroscopy; A. Carbon fibers; A. Polymer-matrix composites (PMCs); B. Interface/interphase; B. Impact behavior
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/j.compositesa.2015.12.015

Octaglycidyl polyhedral oligomeric silsesquioxane (gly-POSS) was successfully grafted on carbon fibers (CFs) surface to enhance interfacial properties and impact toughness of CFs reinforced methylphenylsilicone resin (MPSR) composites. After gly-POSS modification, POSS grafted CF (CF-POSS) with many epoxy functional groups was modified with tetraethylenepentamine (TEPA) to further enhance the interfacial strength. Atomic force microscopy (AFM) images showed that POSS and TEPA were grafted onto CFs surface uniformly and the surface roughness enhanced obviously. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) confirmed the chemical bonding nature between CFs and POSS, as well as between POSS and TEPA. POSS and TEPA modification could increase the fiber polarity, wettability and surface energy significantly. The interlaminar shear strength (ILSS) and impact toughness of composites showed a dramatic improvement, especially for grafting with POSS and further with TEPA (CF-POSS-TEPA). Additionally, the reinforcing and toughening mechanisms were also analyzed. Meanwhile, single fiber tensile strength (TS) had no decrease after modification.