Effect of fluorinated hydrophobic monomer on the drug release behavior for the thermosensitive hydrogels

Three series of copolymeric gels based on N-isopropylacrylamide (NIPAAm) and perfluoroalkyl methacrylate such as 2,2,3,3,4,4,5,5-octafluoropentyl methacrylate (OFPMA), 4,4,5,5,6,7,7,7-octafluoro-2-hydroxy-6-(trifluoromethyl)heptyl methacrylate (OFHHMA), and 3,3,4,4,5,6,6,6-octafluoro-5-(trifluoromethyl)hexyl methacrylate (OFHMA), were prepared by emulsion polymerization. The effect of perfluoroalkyl methacrylate and sodium lauryl sulfate (SLS), which can act as a surfactant and a pore-forming agent, on the equilibrium swelling ratio and mechanical properties of the present hydrogels was investigated. Results show that hydrophobic monomers made the swelling ratio of the gel decrease and the mechanical property of the gel increase; however, SLS exhibits a contrary result. In addition, the effect of perfluoroalkyl methacrylate on the drug release behavior was also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4661–4667, 2006