synthesis of some network polymers with siloxane units as a drug delivery system

new biodegradable network polymers containing siloxane-linked polymeric prodrugs of 5-ammino-2-hydroxybenzoic acid (5-asa) in the main chain were prepared by ter polymerization of methacrylic acid (ma), 2-hydroxyethylmethacrylate (hema), and bis (trimethylsilyloxy) methylsilane (vbm) in the presence of some new cross-linking agents.the monomers and polymers were characterized by ft-ir and 1h-nmr spectroscopy, and their thermal stability studied by dsc analysis. the hydrolysis of them were carried out in cellophane membrane dialysis bags containing aqueous buffer solution at 37 c. detection of the hydrolysis product by uv spectroscopy method showed that attaching of siloxane units in these hydrogels modified this drug delivery system.