Studies on thermal and dielectric properties of Octa (maleimido phenyl) silsesquioxane (OMPS) - polybenzoxazine (PBZ) hybrid nanocomposites

Abstract

Polybenzoxazine (PBZ) hybrid nanocomposites were prepared from new type of allyl-terminated benzoxazine monomer and various weight percentage of Octa (maleimido phenyl) silsesquioxane (OMPS). The allyl terminal benzoxazine monomer was synthesized from 1,1-bis (3-methyl-4-hydroxy phenyl) cyclohexane with allyl amine and formaldehyde through Mannich condensation and it was characterized by using Fourier transform infrared, 1H-NMR and 13C-NMR spectroscopy. Data from differential scanning calorimetry (DSC) analysis shows that the newly synthesized benzoxazine monomer (BZ-Cy-al) begins to show ring opening polymerization at lower temperature than that of conventional allyl terminal benzoxazine (BZ-al).Thermal properties of hybrid nanocomposites were analysed by using DSC and thermogravimetric analyser. The POSS-PBZ nanocomposites possess higher glass transition temperature and thermal stability than that of neat PBZ. Dielectric properties of hybrid polybenzoxazine nanocomposites were found decreasing with an increase in the OMPS content. The water absorption properties of hybrid polybenzoxazine nanocomposites decrease with increase in OMPS content. A homogeneous morphological behavior of the hybrid nanocomposites were studied by X-ray diffraction, scanning electron microscopy and transmission electron microscopy analysis.