Hybrid composites are a class of material that have gained substantial recognition due to their highly sought-after properties of both organics and inorganics. A novel method for incorporating inorganic content into urethane materials is through the use of organically modified silicate cross-linkers. Glycol-modified silanes, in particular, allow for the facile preparation of highly cross-linked urethane materials with a wide range of bulk and surface characteristics including glass transition temperature (40.485.6 degrees C), storage modulus (0.71.62 GPa), and surface energy (19.062.4 dynes cm1). Importantly, control of the overall polymer properties remains achievable via the structural control of macrodiols and isocyanates. Additionally, incorporation of silicate cross-linkers into urethane systems provides these materials with a hydrolyzable character, which may be controlled by altering the bulk polymer composition, cross-link density, and surface energy. The unique nature of these systems also allows for the preparation of highly cross-linked urethanes in the absence of any heavy metal catalysts and depending on the composition, with the use of little to no solvent. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013