端基为C—Br键新型聚季铵盐的合成与表征

Synthesis and characterization of poly quaternary ammonium salt of the C—Br terminal bond

以N,N,N′,N′-四甲基乙二胺(TMEDA)和二溴乙烷(EDB)为原料,通过聚合反应制备了一种端基为C—Br键的高电荷密度聚季铵盐,考察了反应介质、原料摩尔比、物料总浓度、反应温度和反应时间对原料转化率及聚季铵盐相对分子质量的影响。试验结果表明,以乙醇为溶剂,二溴乙烷和四甲基乙二胺的摩尔比为1∶1,物料总浓度1.625mol/L,反应时间8h,反应温度75℃,四甲基乙二胺转化率为51.69%,聚季铵盐相对分子质量为5 035。红外光谱和核磁谱图表明聚季铵盐结构与预期的一致,热重曲线表明聚季铵盐有良好的热稳定性。

The polymeric quaternary ammonium salt （polyQACs） with C--Br end group and high charge density was synthesized by copolymerization of N,N,NI,NCtetramethyl ethylene diamine （TMEDA） and ethylene dibromide （EDB）. The influences of reaction medium, monomer molar ratio, raw material concentration, reaction temperature, reaction time on conversion and average molecular weight were studied. When ethanol as solvent, n（EDB） ： n（TMEDA） = 1 ： 1, the total concentration of raw materials was 1. 625 mol/L, reaction time was 8 h, reaction temperature was 75 ℃, the conversion rate of TMEDA and the average molecular weight of polymeric quaternary ammonium salt respectively reached 51.69% and 5 035. The structure of polyQACs was characterized by FT-IR and NMR, respectively. The result showed that the structure of product accorded with the anticipated structure. The TGA curves showed that the polymeric quaternary ammonium salt had good thermal stability.