Reactivity of Organosilane Reagents on Microparticulate Silica

Article abstract of DOI:10.1021/ac00295a021

Competitive surface reactions between binary organosilane mixtures and microparticulate silica were undertaken to determine if the surface composition of chemically modified silicas could be controlled by varying the molar composition and addition rate of the reagent mixture.X-ray fluorescence (XRF) spectroscopy and elemental carbon analysis permitted differences in silane reactivity to be evaluated as a function of alkyl chain length for a series of haloalkylsilanes.The rate of addition and the presence of a catalyst were found to control the surface composition of silicas derivatized from binary si lane mixtures.Comparison of X-ray photoelectron spectroscopy data with XRF results was used to determine the spatial distribution of the immobilized silanes in order to evaluate the extent to which diffusion controls the relative reactivity of organosilane reagents.