Interfacially reinforced carbon fiber composites by grafting modified methylsilicone resin

Modified methylsilicone resin (12EO(15)-MA-SiO2/MSR) containing nano-silica grafted hyperbranched polymer (12EO(15)-MA-SiO2) was grafted successfully onto carbon fibers (CFs) surface to enhance the interfacial properties of carbon fiber/methylsilicone resin composites. Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) confirmed the chemical bonding nature between 12EO(15)-MA-SiO2/MSR and CFs. Scanning electron microscopy (SEM) and interfacial shear strength (IFSS) indicated that the surface morphology and interfacial properties of carbon fibers were highly dependent on the concentration of 12EO(15)-MA-SiO2 and 12EO(15)-MA-SiO2/MSR. The results showed that the optimal condition was that the concentration of 12EO(15)-MA-SiO2/MSR was 1%, in which containing 6%-12EO(15)-MA-SiO2. Furthermore, significant enhancement of interfacial shear strength was achieved in the composites after modified methylsilicone resin introduced on the fiber. The tensile strength of the carbon fibers remained stable after the grafted treatment. Thus, it is a facile and effective interface design strategy to develop multifunctional fibers with desirable properties in industry applications. (C) 2016 Elsevier Ltd. All rights reserved.