Antibacterial polymers of dimethylaminoethyl methacrylate benzyl ammonium chloride（DMAEMA-BC） with various molecular weights（Mws） were prepared under controlling radical polymerization conditions. The Mws of these...Antibacterial polymers of dimethylaminoethyl methacrylate benzyl ammonium chloride（DMAEMA-BC） with various molecular weights（Mws） were prepared under controlling radical polymerization conditions. The Mws of these polymers were determined by means of static multiangle laser light scattering and viscosity method. A Mark-Houwink equation was established to be [η]=0.154M0.764 for the Mw evaluation of poly（DMAEMA-BC）s. The effects of the Mws of these poly（DMAEMA-BC）s on their antibacterial activities against E. coli and S. aureus were investigated by various methods including viable cell counting, electrical conductivity titration, intracellular constituent leakage tests and electron microscopy. Our results indicate that the antibacterial efficiency of DMAEMA-BC was significantly enhanced after the monomers were polymerized into a polymer and increased obviously with the Mws,as a result of the increase of charge density. Further investigation of the molecular basis underlying the anti-bacterial role of these polymers revealed that poly（DMAEMA-BC） promoted the release of potassium ion from the membrane of bacterial cells and the release increased significantly with the Mws of the polymers used.展开更多
使用自制的低分子质量壳聚糖季铵盐对亚麻织物进行改性,绘制改性后亚麻织物活性染料染色上染速率曲线和吸附等温线,并进行热力学和动力学的拟合、计算.结果发现:改性后亚麻织物活性染料染色上染速率曲线符合准二级模型,较符合准一级模型...使用自制的低分子质量壳聚糖季铵盐对亚麻织物进行改性,绘制改性后亚麻织物活性染料染色上染速率曲线和吸附等温线,并进行热力学和动力学的拟合、计算.结果发现:改性后亚麻织物活性染料染色上染速率曲线符合准二级模型,较符合准一级模型,属于非定位多分子层吸附;吸附等温线符合Langmuir(朗格缪尔)模型,较符合Freundlich(弗罗因德利希)模型,同时存在定位吸附和非定位吸附,染色平衡吸附量随着温度的升高而降低;亲和力随着染色温度的升高而降低,染色热为-27.586 k J/mol,染色过程是放热反应,染色熵为-0.056 5 k J/(mol·K),染料在纤维上的取向程度较小.展开更多
基金Supported by the National Natural Science Foundation of China(No.50673101)the Project of Department of Education of Guangdong Province,China(No.cgzhzd0901)
文摘Antibacterial polymers of dimethylaminoethyl methacrylate benzyl ammonium chloride（DMAEMA-BC） with various molecular weights（Mws） were prepared under controlling radical polymerization conditions. The Mws of these polymers were determined by means of static multiangle laser light scattering and viscosity method. A Mark-Houwink equation was established to be [η]=0.154M0.764 for the Mw evaluation of poly（DMAEMA-BC）s. The effects of the Mws of these poly（DMAEMA-BC）s on their antibacterial activities against E. coli and S. aureus were investigated by various methods including viable cell counting, electrical conductivity titration, intracellular constituent leakage tests and electron microscopy. Our results indicate that the antibacterial efficiency of DMAEMA-BC was significantly enhanced after the monomers were polymerized into a polymer and increased obviously with the Mws,as a result of the increase of charge density. Further investigation of the molecular basis underlying the anti-bacterial role of these polymers revealed that poly（DMAEMA-BC） promoted the release of potassium ion from the membrane of bacterial cells and the release increased significantly with the Mws of the polymers used.
文摘使用自制的低分子质量壳聚糖季铵盐对亚麻织物进行改性,绘制改性后亚麻织物活性染料染色上染速率曲线和吸附等温线,并进行热力学和动力学的拟合、计算.结果发现:改性后亚麻织物活性染料染色上染速率曲线符合准二级模型,较符合准一级模型,属于非定位多分子层吸附;吸附等温线符合Langmuir(朗格缪尔)模型,较符合Freundlich(弗罗因德利希)模型,同时存在定位吸附和非定位吸附,染色平衡吸附量随着温度的升高而降低;亲和力随着染色温度的升高而降低,染色热为-27.586 k J/mol,染色过程是放热反应,染色熵为-0.056 5 k J/(mol·K),染料在纤维上的取向程度较小.
