A new effecient catalyst system(FeCl 3/2PPh 3) for the “living”/controlled radical polymerization of butyl methacrylate by a reverse ATRP process was reported in this paper.With the presence of this catalyst system,...A new effecient catalyst system(FeCl 3/2PPh 3) for the “living”/controlled radical polymerization of butyl methacrylate by a reverse ATRP process was reported in this paper.With the presence of this catalyst system,the number average molecular weights of the obtained polymer increased in direct proportion with monomer conversion,and the MWDs (molecular weight disctributions) were narrow throughout the reactions(1 17< w/ n<1 22).This reaction system did not include the conventional initiators which were used to generate the primary radicals.展开更多
通过扫描电子显微镜观察了天然橡胶和高吸水树脂共混体系的微观相态结构 ,研究了两亲性嵌段共聚物PEO b PBA结构本身的吸水能力对天然橡胶和高吸水性树脂共混体系吸水性能及力学性能的影响。结果表明 ,PEO b PBA结构本身的吸水强弱对共...通过扫描电子显微镜观察了天然橡胶和高吸水树脂共混体系的微观相态结构 ,研究了两亲性嵌段共聚物PEO b PBA结构本身的吸水能力对天然橡胶和高吸水性树脂共混体系吸水性能及力学性能的影响。结果表明 ,PEO b PBA结构本身的吸水强弱对共混体系的吸水能力贡献很小 ,但却可以显著提高共混体系的吸水膨胀能力和力学性能 。展开更多
The poly(2,5-dipentyloxy-para-phenylene ethynylene)(P) was synthesized by Pd-catalyzed Sonogashira coupling reaction.Due to causing energy transfer between the nitrobenzene’s quenchers and the polymer chains through ...The poly(2,5-dipentyloxy-para-phenylene ethynylene)(P) was synthesized by Pd-catalyzed Sonogashira coupling reaction.Due to causing energy transfer between the nitrobenzene’s quenchers and the polymer chains through the charge-transfer interaction,the fluorescence quenched properties of P varied obviously with the para-substituting group’s structure in the nitrobenzene derivatives.The fluorescence quenching efficiency of quenchers improved with increasing of electron repulsion capability of the para-substituting group.The fluorescence quenching efficiency increased nonlinearly with the concentration of the quenchers and had,however,no relation with the quenching time.展开更多
文摘A new effecient catalyst system(FeCl 3/2PPh 3) for the “living”/controlled radical polymerization of butyl methacrylate by a reverse ATRP process was reported in this paper.With the presence of this catalyst system,the number average molecular weights of the obtained polymer increased in direct proportion with monomer conversion,and the MWDs (molecular weight disctributions) were narrow throughout the reactions(1 17< w/ n<1 22).This reaction system did not include the conventional initiators which were used to generate the primary radicals.
文摘通过扫描电子显微镜观察了天然橡胶和高吸水树脂共混体系的微观相态结构 ,研究了两亲性嵌段共聚物PEO b PBA结构本身的吸水能力对天然橡胶和高吸水性树脂共混体系吸水性能及力学性能的影响。结果表明 ,PEO b PBA结构本身的吸水强弱对共混体系的吸水能力贡献很小 ,但却可以显著提高共混体系的吸水膨胀能力和力学性能 。
文摘The poly(2,5-dipentyloxy-para-phenylene ethynylene)(P) was synthesized by Pd-catalyzed Sonogashira coupling reaction.Due to causing energy transfer between the nitrobenzene’s quenchers and the polymer chains through the charge-transfer interaction,the fluorescence quenched properties of P varied obviously with the para-substituting group’s structure in the nitrobenzene derivatives.The fluorescence quenching efficiency of quenchers improved with increasing of electron repulsion capability of the para-substituting group.The fluorescence quenching efficiency increased nonlinearly with the concentration of the quenchers and had,however,no relation with the quenching time.
