This paper reports the synthesis of methoxyoligo (oxyethylene) methacrylate (MEO_n , n is the repeating unit number of (CH_2CH_2O) in the macromonomer), and its polymerization in different solvents. MEO_n is prepared ...This paper reports the synthesis of methoxyoligo (oxyethylene) methacrylate (MEO_n , n is the repeating unit number of (CH_2CH_2O) in the macromonomer), and its polymerization in different solvents. MEO_n is prepared through such two independent reactions as (1) anionic polymerization of oxirane initiated by potassium alkoxide and (2) end-capping of methoxy oligo(oxyethylene) by methacrylic group. The n value can be conveniently controlled over the range of 5 ～ 30 by varying the molar ratio of oxirane to initiator and the molecular weight distribution of MEO_n be narrowed by increasing reaction time only in step (1). MEO_n thus obtained shows a rapid polymerization in water and benzene respectively, and both give water-soluble polymers as long as suitable conditions are used.展开更多
Ionomeric networks(IN)with lithium sulfate and sait-solvating oligo(oxyethylene)chain were synthesized on the purpose of improving the conductivity of single-Li^+-ionic conductors.Li^+-ionic conductivity depends consi...Ionomeric networks(IN)with lithium sulfate and sait-solvating oligo(oxyethylene)chain were synthesized on the purpose of improving the conductivity of single-Li^+-ionic conductors.Li^+-ionic conductivity depends considerably on the salt content of the INs although the apparent degree of cross- linking is fixed in a constant of 10 mol%.As salt content(Li/O value)equals 0.0467,conductivity of the IN containing neither small-molecular salt nor low molecular weight plasticizer reaches a maximum of 7×10^(-6) S/cm at 25℃.Temperature-conductivity relationship of the INs shows curved Arrhenins plots,suggesting that the ionic conduction is primarily influenced by segmental motion of the polymer host.In addition,WLF(Williams-Landel-Ferry)equation is used to analyze the conductivity data, from which the related WLF parameters are determined.展开更多
文摘This paper reports the synthesis of methoxyoligo (oxyethylene) methacrylate (MEO_n , n is the repeating unit number of (CH_2CH_2O) in the macromonomer), and its polymerization in different solvents. MEO_n is prepared through such two independent reactions as (1) anionic polymerization of oxirane initiated by potassium alkoxide and (2) end-capping of methoxy oligo(oxyethylene) by methacrylic group. The n value can be conveniently controlled over the range of 5 ～ 30 by varying the molar ratio of oxirane to initiator and the molecular weight distribution of MEO_n be narrowed by increasing reaction time only in step (1). MEO_n thus obtained shows a rapid polymerization in water and benzene respectively, and both give water-soluble polymers as long as suitable conditions are used.
文摘Ionomeric networks(IN)with lithium sulfate and sait-solvating oligo(oxyethylene)chain were synthesized on the purpose of improving the conductivity of single-Li^+-ionic conductors.Li^+-ionic conductivity depends considerably on the salt content of the INs although the apparent degree of cross- linking is fixed in a constant of 10 mol%.As salt content(Li/O value)equals 0.0467,conductivity of the IN containing neither small-molecular salt nor low molecular weight plasticizer reaches a maximum of 7×10^(-6) S/cm at 25℃.Temperature-conductivity relationship of the INs shows curved Arrhenins plots,suggesting that the ionic conduction is primarily influenced by segmental motion of the polymer host.In addition,WLF(Williams-Landel-Ferry)equation is used to analyze the conductivity data, from which the related WLF parameters are determined.
