Mechanically strong polystyrene nanocomposites by peroxide-induced grafting of styrene monomers within nanoporous cellulose gels

Nanocellulose is a promising candidate as a green reinforcing nanofiller for polymer nanocomposites. Three-dimensionally nanoporous cellulose gels (NCGs) have been demonstrated to exhibit significant dispersibility and compatibilization with hydrophobic polymers. We report a simple and versatile process for the fabrication of NCG/polystyrene (PS) nanocomposites by the in situ free radical polymerization of styrene monomers within the NCG. The volume fraction of the NCG in the NCG/PS nanocomposites could be controlled from 10% to 60%. The interconnected nanofibrillar cellulose networks of the NCG were finely distributed and well preserved in the PS matrix after polymerization. Dynamic mechanical analysis revealed a remarkable reinforcement in the tensile storage modulus of the NCG/PS nanocomposites, especially above the glass transition temperature (T-g) of the PS matrix. The modified percolation model was in good agreement with the mechanical properties of the NCG/PS nanocomposites. The introduction of the NCG into the PS matrix significantly improved the flexural and tension properties of the NCG/PS nanocomposites.