Effect of nano-SiO2 on properties of wood/polymer/clay nanocomposites

Wood polymer nanocomposites (WPNC) based on nano-SiO₂ were prepared by impregnation of styrene acrylonitrile copolymer (SAN), SiO₂ nanoparticles modified with γ-trimethoxy silyl propyl methacrylate (MSMA), and nanoclay into wood. The structure of modified SiO₂ nanoparticles and WPNC was characterized by Fourier transform infrared spectroscopy (FTIR). XRD analysis showed the delaminated structure of SAN/SiO₂/clay-treated wood composites. The synergistic effect of nano-SiO₂ and nanoclay was investigated. Thermal stability of SiO₂ nanoparticles decreased after modification, while that of wood treated with SAN, SiO₂, and nanoclay improved. Morphological characteristics were examined by scanning electron microscopy (SEM). Mechanical properties, water uptake (%), dimensional stability, hardness, and flammability were found to improve due to incorporation of SiO₂ and nanoclay into wood polymer composites. Maximum improvement in properties was observed in the wood polymer composites containing SiO₂ and nanoclay at the ratio of 1:1.