Interfacial Coupling by Alkoxytitanium and -Zirconium Tricarboxylates

Abstract

i-Propoxytitanium trilaurate and i-propoxyzirconium tristearate, prepared by established methods from the appropriate tetraalkoxide and fatty acid, have been shown to contain traces of i-propyl laurate and stearate respectively. This finding has an important bearing upon the potential ability of certain commercially marketed alkoxytitanium tricarboxylates to act as coupling agents for bonding epoxy adhesives to metals and to other substrates. I.r. spectral studies show that i-propoxytitanium and -zirconium tristearate interact with silica and alumina powders by exclusive loss of i-propanol, rather than a stearic acid residue, and that the titanate (or zirconate) is largely resistant to desorption from the substrate by treatment with hot water.