New crosslinking reagent that has silyl group together with ethyl hydroxyl methacrylate was successfully synthesized. Network polymers with this crosslinked reagent, methacrylic acid, and silyl monomers of 2-hydroxyethyl methacrylate ester were synthesized and studied their properties. These sily monomers are: 2-[(triethylsilyl)oxy] ethyl methacrylate, 2-((tert-butyldimethylsilyl) oxy) ethyl methacrylate, and 2-((triphenylsilyl) oxy) ethyl methacrylate. All monomers and polymers were identified by spectroscopic methods. Then mesalasine was entrapped in these network polymers and the in vitro release profiles were established separately in both enzyme-free simulated gastric and intestinal fluids (SGF, pH 1) and (SIF, pH 7.4), respectively. In vitro release studies showed that these network polymers can be good candidates for colon-specific drug delivery. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 2368-2373, 2011