Correlation equations describing retention index data forn-alkylcyclopentenes,n-alkylcyclohexenes andn-alkyl esters on OV-101, OV-225 and PEG 20M

Fourier-Transform Infrared Spectroscopy Studies of the Interaction of Functionalized Siloxane Polymers with Porous Silica

Adsorption behavior of the siloxane polymer, cyanopropylmethyl-phenyl-methyl-siloxane, in contact with a mesoporous silica has been investigated by Fourier-transform infrared spectroscopy (FT-IR) using a series of physically modified materials with different coating levels up to 20 w/w%. The nitrile stretch bands, which are observed in the 2150-2350 cm(1) range, exhibited complex profiles due to a variety of interactions of the cyano groups within the polymer and with the surface silanols. These complex bands have been resolved into multiple components using a curve-fitting procedure. Three major spectral components have been found and assigned to the nitrile stretch in the bulk polymer, interfacial polymer, and polymer attached to surface silanols via hydrogen bonding. The latter spectral component is dominating for the samples with low coating levels. Its relative contribution decreased with the increasing amount of the polymer on the silica surface due to increasing contribution of the pure-polymer spectral component. Copyright 2000 Academic Press.