Improved dielectric and mechanical properties of silica/epoxy resin nanocomposites prepared with a novel organic-inorganic hybrid mesoporous silica: POSS-MPS

The novel organic-inorganic particles (denoted POSS-MPS) were synthesized by the reaction of amino-functionalized mesoporous silica (NH2-MPS) with a wormhole framework structure and glycidyl polyhedral oligomeric silsesquioxane (G-POSS), and were employed as reinforcing agents to prepare POSS-MPS/epoxy resin (EP) nanocomposites. The retaining mesoporous structure of POSS-MPS was verified by TEM and N-2 adsorption-desorption. The excellent improvement in dielectric properties, thermal properties and mechanical properties of the POSS-MPS/EP nanocomposites is ascribed to increase of voids volume and reinforcement of interfacial interaction between organic and inorganic phase in the composites. The POSS-MPS/EP nanocomposites containing 5 wt% of POSS-MPS showed a lower dielectric constant (kappa=3.66) and loss factor (tan delta=0.017) in comparison to pristine EP with the value of 4.03 and 0.031, respectively. Moreover, the composites exhibited 23.8%, 43.5%, 159.8% and 59.8% enhancement in tensile strength, tensile modulus, elongation at break and glass transmission temperature (T-g) in comparison to pristine EP, respectively. The results manifested that introduction of POSS-MPS improved the mechanical properties, heat resistance and dielectric properties of EP. (C) 2014 Elsevier B.V. All rights reserved.