A series of poly(N-isopropylacrylamide-co-methacryloyloxyethyl dimethyloctyl ammonium bromide) [P (NIPAM-co-ADMOAB)] hydrogels were prepared.The influences of the amount of ADMOAB in copolymeric gels on the swelling b...A series of poly(N-isopropylacrylamide-co-methacryloyloxyethyl dimethyloctyl ammonium bromide) [P (NIPAM-co-ADMOAB)] hydrogels were prepared.The influences of the amount of ADMOAB in copolymeric gels on the swelling behavior were investigated.The deswelling and reswelling kinetics were also studied.Results showed that the equilibrium swelling ratios (ESRs) of copolymeric gels increased with the enhanced ADMOAB content in the composition at temperatures below LCST,and the maximum ESR was 126 compared with a value of 28 for homopolymeric gel P(NIPAM),and the ESR for all copolymeric gels tended to zero independent of the composition when the temperature was above LCST.The rate constants in deswelling process increased at first and then decreased with increasing the ADMOAB amount,and the final water retention for copolymeric gels(about 1%) was much lower than that of P(NIPAM)(20%).The swelling ratios during reswelling process increased with the ADMOAB amount,and the diffusion of water into P(NIPAM-co-ADMOAB) gels was found to be a non-Fickian mode.Though decreased in saline solutions,swelling ratios for copolymeric gels were not significantly influenced by ionic strength with NaCl concentration from 0.1 to 0.3 mol/L and higher than those of homopolymeric gels in deionized water with the same swelling time.P(NIPAM-co-ADMOAB) hydrogels can be expected as good candidates for controlled drug delivery systems and separation processes.展开更多
文摘通过光化学合成方法分别在高温(50℃)和室温(28℃)下实现了N,N-二甲基丙烯酰胺(DMAA)和N-异丙基丙烯酰胺(NIPAm)的交联共聚,制备了两种不同结构的P(DMAA-co-NIPAm)共聚物水凝胶.对两种温度下制备的P(DMAA-co-NIPAm)共聚物水凝胶的网络结构、溶胀与消溶胀速率和温度敏感性等方面进行了比较研究.结果发现,50℃下制备的P(DMAA-co-NIPAm)共聚物凝胶具有较为疏松的网络结构和相对较快的溶胀速率及温度响应特性.光化学合成方法较传统的热聚合制备方法具有简便、快捷的特点,合成过程仅需2 min.
文摘A series of poly(N-isopropylacrylamide-co-methacryloyloxyethyl dimethyloctyl ammonium bromide) [P (NIPAM-co-ADMOAB)] hydrogels were prepared.The influences of the amount of ADMOAB in copolymeric gels on the swelling behavior were investigated.The deswelling and reswelling kinetics were also studied.Results showed that the equilibrium swelling ratios (ESRs) of copolymeric gels increased with the enhanced ADMOAB content in the composition at temperatures below LCST,and the maximum ESR was 126 compared with a value of 28 for homopolymeric gel P(NIPAM),and the ESR for all copolymeric gels tended to zero independent of the composition when the temperature was above LCST.The rate constants in deswelling process increased at first and then decreased with increasing the ADMOAB amount,and the final water retention for copolymeric gels(about 1%) was much lower than that of P(NIPAM)(20%).The swelling ratios during reswelling process increased with the ADMOAB amount,and the diffusion of water into P(NIPAM-co-ADMOAB) gels was found to be a non-Fickian mode.Though decreased in saline solutions,swelling ratios for copolymeric gels were not significantly influenced by ionic strength with NaCl concentration from 0.1 to 0.3 mol/L and higher than those of homopolymeric gels in deionized water with the same swelling time.P(NIPAM-co-ADMOAB) hydrogels can be expected as good candidates for controlled drug delivery systems and separation processes.
