PVA-g-NIPAAm凝胶的辐射制备与缓释研究

Preparation of PVA-g-NIPAAm Hydrogel by γ Radiation and Its Controlled Release Research

研究了在均相体系中通过共辐射接枝法将ＮＩＰＡＡｍ 接枝到ＰＶＡ上。测定了不同因素如剂量，剂量率及酸度对接枝率的影响。采用冷冻熔融的方法制备了ＰＶＡ，ＰＶＡｇＮＩＰＡＡｍ 凝胶，发现ＰＶＡｇＮＩＰＡＡｍ 凝胶具有温度敏感性，用相同方法对ＭＢ包埋固定并研究了不同温度下缓释规律。

Thermosensitive PVA\|g\|NIPAAm copolymers was prepared by grafting copolymerization of N\|isopropylacrylamide (NIPAAm) onto poly(vinyl alcohol) (PVA) in homogeneous system by 60 Co\|γ irradiation at room temperature. The effects of radiation grafting conditions, such as absorption dose, dose rate, acid concentration on grafting yield were investigated. It was found that dose rate and acid concentration had obvious influence on the grafting yield. Then the hydrogels of PVA and PVA\|g\|NIPAAm copolymer were made through freezing\|thawing processes and the later hydrogels obtained in this method were found to exhibit obvious thermal sensitivity. In addition, the slow release of Methylene Blue (MB) from this kind of hydrogels was studied.