J. Howarter, J. Youngblood
Jan 30, 2007
Citations
0
Influential Citations
63
Citations
Journal
Macromolecules
Abstract
Various polymer surfaces were analyzed for reactivity toward 3-aminopropyltriethoxysilane (APTES). Results indicate that the method described here is useful as a general surface-selective modification technique for polar polymers such as polyesters, polyamides, polycarbonates, polyimides, cellulosics, polyacrylics, etc. X-ray photoelectron spectroscopy (XPS) showed an average of 10% silicon and nitrogen atomic concentrations at 75° takeoff for all successfully modified surfaces. The APTES multilayers were subsequently hydrophobized with perfluorinated chlorosilanes giving 40% fluorine atomic concentration by XPS and 120°/90° (advancing/receding) dynamic contact angle averages. APTES modifications were successful in all solvents with the exception of protic solvents. On the basis of these and other observations, a new model for the reaction pathway is proposed. We propose the reaction proceeds by initial APTES adsorption (likely through hydrogen bonding by the amine) to the substrate, lateral bond formatio...