Characterization of Functional Polyphenylsilsesquioxane (PhSiO3/2) Hybrid Glass Reinforced with MWCNTs

Hybrid (inorganic- organic) glass is an emerging material for engineering applications like protection and functional coatings. This material is very brittle and cannot stand mechanical loads. In this work, multi-wall carbon nanotubes were suggested as a reinforcing material to toughen the hybrid glass. Sol-gel method was used to prepare the hybrid glass (melting glass) by mixing two alkoxysilanes precursors, mono-substituted and di-substituted alkoxysilanes. Four weight ratios (0.0125, 0.025, 0.05, 0.25 wt%) of multi-wall carbon nanotubes were employed. The composite coatings were synthesized by mixing multi-wall carbon nanotubes with the sol once and with the gel another route. The mechanical, structural and functional properties to the yield composite films were characterized. The results showed that the addition of multi-wall carbon nanotubes to the hybrid glass has lowered the wettability of the resulting composite, where the maximum contact angle (θ) was 102°. Besides, existing of multi-wall carbon nanotubes in the matrix has increased the hardness of the hybrid glass to about 43 MPa at 0.0125 wt%. Correspondingly, the fracture toughness (kIC) has decreased in comparison to the hybrid glass alone. This refers to lower the glass ability to absorb the energy of fracture. The optical transmission has reduced as the weight ratio of multi-wall carbon nanotubes increased.