Synthesis Of Hybrid Organic Silica With High Silanol Content And Low Amount Of Adsorbed Water Intended To Be Used As Filler In Polyurethane Adhesive

L. MUSANTE, P. VÁZQUEZ, J. VEGA-BAUDRIT, J.M. MARTÍN-MARTÍNEZ

Buenos Aires

Workshop; COMAT 2005; 2005

Hybrid organic-inorganic materials can be synthesized through a sol-gel process in the presence of organic species able to chemically interact with the metal alkoxides. Hybrid material means a disordered physical-chemical system that forms intricate organic and inorganic networks. The degree of linking and cross-linking of the organic and inorganic networks influences the mechanical and chemical properties and can be controlled by varying, for example, the amount of organic precursor, the catalyst or time of stirring mixture. The relative simplicity and versatility of the sol?gel process, when compared to covalent-bonding methods to obtain hybrid materials, associated with low cost, are responsible for its extensive use. The novelty of this study was the preparation method of silica having a high number of surface silanol groups but very low number of adsorbed water molecules. The synthesis procedure consisted in obtaining a sol-gel silica co-synthesized or functionalized by covalent attachment of 3-aminopropyltriethoxysilane (APS) and 1,1,1,3,3,3?hexamethyldisilazane (HDMS), respectively.