检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
出 处:《合成化学》2006年第5期516-519,共4页Chinese Journal of Synthetic Chemistry
摘 要:以N,N,N,′N′-四甲基乙二胺-过硫酸钾为氧化-还原引发体系,用水相沉淀聚合法合成了超高相对分子质量的聚醋酸乙烯(PVAc)。研究了引发剂浓度、反应温度、单体与水用量比、转化率等对聚合反应的影响。其结构用IR表征,相对分子质量及其分布和支化度用GPC测定。结果表明,醋酸乙烯最终转化率为90%~95%,PVAc的平均聚合度为8 000~15 000,相对分子质量分布指数为2.12~2.24,支化度为2.10~2.80。Using N, N, N', N'-tetramethylethylenediamine and potassium persulphate as a redox initiation system, high molecular weight poly( vinyl acetate) (PVAc) was synthesized by aqueous deposi^d polymerization. The effects of concentration of initiator, polymerization temperature, the ratio of VAc to water and conversion of VAc to PVAc on polymerization were discussed. The structure of PVAc was characterized by IR and the relative molecular weight and relative molecular weight distribution were determinated by GPC. The results showed that ultimate conversion of VAc to PVAc was 90% - 95%, the average degree of polymerization of PVAc was 8 000 - 15 000, the relative molecular weight distribution index of PVAc was 2.12 - 2.24, and the degree of branching of PVAc was 2.10 - 2.80.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.182