Preparation of PHEMA Hydrogels with a Nano Cagelike POSS as Cross Linker and Its Drug Release Behaviour of Norfloxacin

A novel series of P(OVPS-co-HEMA) hydrogels were prepared by the solution free radical polymerization using hydroxyethyl methacrylate(HEMA) as monomer and octavinyl polyhedral oligomeric silsesquioxane(OVPS) as the cross linker. The structure and properties of hydrogels were characterized by 1H-NMR, FT-IR, SEM, DSC, TG, DMA and UV technologies. Results show that the mass fraction of OVPS in P(OVPS-co-HEMA) hybrid hydrogels can be controlled by the feed ratios of the copolymerization. The cross linking density of P(OVPS co HEMA) hydrogels increases with the increasing of the OVPS mass fraction. The sizes of the hydrogel holes decrease from 10-15 μm to 5-10 μm. The mechanical property of P(OVPS-co-HEMA) hydrogels is improved with the incorporation of OVPS. The P(OVPS-co-HEMA) hydrogels display an excellent norfloxacin controlled release behavior. The drug release time is about 96 h and the cumulative release percentage can reach 99.56%. The P(OVPS-co-HEMA) hydrogels can be potentially used as contact lens, keratoprosthesis and tissue engineering materials.