EPOXY NETWORKS MODIFIED BY AMINE- AND CARBOXYL-FUNCTIONALIZED SILSESQUIOXANES

I. E. DELL'ERBA; R. J. J. WILLIAMS

Viña del Mar

Simposio; IV Argentine-Chilean Polymer Symposium"; 2007

Universidad de Chile

Silsesquioxanes (SSO) are a unique class of organic-inorganic compounds consisting of a silicon ? oxygen polyhedral framework with a silicon atom in each vertex and an organic group (R) covalently bonded to it[1]. Diameter of the Si-O core is about 0.55 nm. General formula for SSO is RnSinO(3n/2)-x(OH)2x, (abbreviated Tn(OH)m). For completely condensed species (x = 0 and n = even number ³ 6) formula reduces to RnSinO3n/2 (abbreviated Tn). Silsesquioxanes are widely used in the preparation of organic ? inorganic materials, mainly by introducing them into the formulations of thermosetting polymers. Mechanical and thermal properties of the polymer are often improved by the addition of SSO. When organic groups (R) of the SSO bear reactive functionalities (C=C, OH, NH, COOH), silsesquioxane is able to form covalent bonds with the polymer network, leading to a nano-reinforced material. In this work, we show the synthesis of two particular silsesquioxanes: An amine-functionalized silsesquioxane (SSO1) and a carboxyl-functionalized silsesquioxane (SSO2). These silsesquioxanes were then used to modify an epoxy network based on the homopolymerization of diglycidylether of bisphenol A (DGEBA). Main features of the polymerization process and properties of the final material are discussed