Synergistic effect of three-dimensional multi-walled carbon nanotube-graphene nanofiller in enhancing the mechanical and thermal properties of high-performance silicone rubber

The homogeneous dispersion of nanofillers and filler-matrix interfacial interactions are important factors in the development of high-performance polymer materials for various applications. In the present work, a simple solution-mixing method was used to prepare multi-walled carbon nanotube(MWCNT)-graphene (G) (3: 1, 1: 1, 1: 3) hybrids followed by their characterization through wide-angle X-ray diffraction, transmission electron microscopy and thermogravimetric analyses. Subsequently, MWCNT-G (1: 1) hybrid was used as reinforcing filler in the formation of silicone rubber (VMQ) nanocomposites by solution intercalation, and their morphology and properties were investigated. Our findings showed that MWCNT-G (0.75 wt%)/VMQ composite exhibited significant improvements in tensile strength (110%) and Young's modulus (137%) compared to neat VMQ. The thermal stability of MWCNT-G (1 wt%)/VMQ was maximally improved by 154 degrees C compared to neat VMQ. Differential scanning calorimetry demonstrated the maximum improvement of glass transition temperature (4 degrees C), crystallization temperature (8 degrees C) and melting temperature (5 degrees C) for MWCNT-G (1 wt%)/VMQ nanocomposite with respect to neat VMQ. Swelling measurements confirmed that the crosslink density and solvent resistance were a maximum for hybrid nanocomposites. Such improvements in the properties of MWCNT-G/VMQ nanocomposites could be attributed to a synergistic effect of the hybrid filler. (C) 2013 Society of Chemical Industry