P(AM-DMDAAC-AA)两性聚电解质的合成及其对白水中Ca^(2+)吸附性能的研究

Synthesis of AM-DMDAAC-AA Polyampholyte and its Application as Adsorbent of Calcium Ions in White Water

以丙烯酰胺(AM)为分子骨架,丙烯酸(AA)和二甲基二烯丙基氯化铵(DMDAAC)分别为阴、阳离子单体,采用过硫酸钾(KPS)与偶氮二异丁脒盐酸盐(AIBA.2HCl)组成的复合引发体系,在水相中共聚合成了一种具有两性特征的水溶性高聚物P(AM-DMDAAC-AA)。通过考察单体质量分数、引发剂用量、单体配比等因素对产物特性黏数和Ca2+吸附性能的影响,确定了反应的最佳合成条件:单体摩尔比n(AM)∶n(DMDAAC)∶n(AA)=1∶0.3∶0.8,单体质量分数22.5%(单体总质量对反应体系总质量),引发剂用量0.2%(相对于单体总质量),其中KPS与AIBA.2HCl的质量比为3∶1,反应温度70～75℃,反应时间10 h。合成的聚合物特性黏数为231.48 mL/g,Ca2+吸附量最高能达到2.028 mmol/g。运用FT-IR和1H-NMR对聚合物结构进行了表征。

Using acrylamide（AM） as the molecular backbone,acrylic acid（AA） as anionic monomer,and dimethyl diallyl ammonium chloride（DMDAAC） as the cationic monomer,complex of KPS and azo-compounds AIBA·2HCl as initiator,the water-soluble polyampholyte P（AM-DMDAAC-AA） was prepared in the aqueous solution.The influences of monomer concentration,dosage of initiator and monomer molar ratio on intrinsic viscosity and adsorption property of Ca2＋ of the polyampholyte were investigated.The optimal conditions were found as follows： n（AM）∶ n（DMDAAC）∶ n（AA）=1∶ 0.3∶ 0.8,monomer concentration 22.5%,dosage of initiator 0.2%,while mass ratio of KPS and AIBA·2HCl 3∶ 1,reaction temperature 70~75℃,reaction time 10 h.Under these conditions,intrinsic viscosity of the polyampholyte was 231.48 mL/g,maximum adsorption capacity of Ca2＋ was 2.028 mmol/g.The structure of the polymer was characterized and studied by the FT-IR and 1H-NMR.