Study On Silicane Modified Copolymer Hydrogel For Contact Lens

In this paper, silicane modified copolymer hydrogel for contact lens with high oxygen permeability were prepared by copolymerization of KH570, N-Vinylpyrrolidone (NVP) and Hydroxyethylmethacrylate (HEMA) , influence of monomers on the properties of the hydrogel were studied, and delayed release of chloramphenicol by the hydrogel were studied as well.When AIBN was used as initiator and the reaction carried on for 28 hours under the temperature of 80℃, the copolymer of KH570-NVP-HEMA was transparent hydrogel after fully swollen, and the stretch intensity of the hydrogel increases with decreasing of the content of NVP and increasing of the content of KH570 in the hydrogel.The swelling behavior of the copolymer hydrogel were studied by weight and TG analysis, the results showed that EWC of the hydrogel change little with the change of temperature, and decreases with the content of NaCl increasing. Excess swelling were observed and the swelling index was different with Fick's swelling index, the swelling kenetics was non-Fick type. The EWC of the copolymer hydrogel increases with increasing of the content of NVP in the hydrogel, while decreases with increasing of the content of KH570 in the hydrogel.The dehydration mechanism of the copolymer hydrogel were studied, and 2 mechanisms were given to explain different dehydration mechanism at different dehydration stages. At the first dehydration stage, the kenetics index was 1 and the evaporation was the key factor which influence the dehydration process, and the kenetics index was 0.5 at the second dehydration stage. The dehydration rate of the copolymer hydrogel increased with temperature and the content of NVP, while decreased with increases of the concentration of NaCl in the solution and the content of KH570.Permeability of the copolymer hydrogel in case of Na~+ and oxygen was...