title: Highly populated and nearly monodispersed nanosilica particles in an organic medium and their epoxy nanocomposites.
abstract: An organic aminopropyl-functionalized nanosilica sol was synthesized in the presence of ethyl silicate, γ-(aminopropyl)triethoxysilane (KH550), and N,N-dimethylformamide (DMF) via a sol-gel technique and then used to prepare epoxy nanocomposites. Structure and morphology analyses of the obtained aminopropyl-functionalized nanosilicas were observed by dynamic light scattering (DLS), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM). TEM and DLS showed that modified nanosilicas with an average diameter of 30 nm dispersed homogeneously in DMF. The effects of the aminopropyl-functionalized nanosilica particles on the flexural modulus, impact strength, glass transition temperature (Tg), and bulk resistivity (ρv) of the epoxy nanocomposites were investigated. The toughening mechanisms and microstructures were determined in terms of the impact fracture surface morphology using scanning electron microscopy.
authors.affiliation: Nano-Science & Technology Research Center and ‡Department of Chemistry, College of Science, Shanghai University , 99 Shangda Road, Shanghai 200444, People's Republic of China.
authors.forename: Wenqi
authors.initials: W
authors.lastname: Yu
authors.forename: Jifang
authors.initials: J
authors.lastname: Fu
authors.forename: Xing
authors.initials: X
authors.lastname: Dong
authors.forename: Liya
authors.initials: L
authors.lastname: Chen
authors.forename: Haisen
authors.initials: H
authors.lastname: Jia
authors.forename: Liyi
authors.initials: L
authors.lastname: Shi