两性高分子絮凝剂P(AM-DM-MA)的合成及性能评价

Synthesis and Performance Properties of P(AM/DM/MA) as Amphoteric Polymeric Flocculant

在引发剂存在下使丙烯酰胺 (AM)、二甲基二烯丙基氯化铵 (DM)、马来酸 (MA)在水溶液中共聚合 ,将共聚物提纯后得到了两性共聚物P(AM /DM/MA) ,收率约 92 %。红外光谱图、1H核磁共振谱图确证了共聚物的结构 ,用元素分析法测定了共聚物的组成 ,AM、DM、MA(以 COOH 计 )的摩尔分数分别为 87.5 %、8.9%和 3.6 %。以3%硅藻土水悬浮液充当模拟污水 ,考察了不同加剂量和 pH值下共聚物的絮凝性能 (通过沉降体积和透光率测定 )。共聚物加量为 8mg/L时透光率即高达 97.5 %,加量在 8～ 30 0mg/L时絮凝效果保持优良 ;pH <6 .7时透光率维持高值 ,pH值在 6 .7～ 9.3时 (等电点附近 )透光率很差 ,絮凝效果不良。P(AM/DM /MA)是一种极具发展潜力的水处理剂。

An amphoteric polymer, P(AM/DM/MA), is synthesized by copolymerization of acrylamide (AM), dimethyldiallylammonium chloride (DM), and maleic acid (MA) at the presence of initiator in aqueous solution and appropriate purification with yield ～92%. The terpolymer structure is identified by infrared spectroscopy and 1H NMR and the terpolymer composition determined from elemental analysis data is : 87.5 mol% of AM, 8.9 mol% of DM, and 3.6 mol% of acid (-COOH). The flocculating ability of the terpolymer for 3% aqueous celite suspensions is investigated through precipitate volume and light transmision measurements at different use levels and pH values. High light transmision of 97.5% is observed with terpolymer in amount of 8 mg/L and excellent flocculating ability is maintained with 8-300 mg of terpolymer per liter suspension added. The transmision is high at pH<6.7 and low at pH 6.7-9.3(near isoelectric point). P(AM/DM/MA) is a well promising water treating agent.