对有机添加剂聚丙烯酰胺进行羟胺化改性,得到非离子型聚丙烯酰胺,在pH值为11,温度为80℃,羟胺和酰胺的量比为1∶2,加入强电解质的条件下,产品的羟胺化程度较高.先将铝酸钠溶液加入反应釜中,再将有机混合添加剂稀释后与晶种充分混匀加入反应釜中进行种分实验,并与无添加剂的情况进行对比.结果表明:相对分子质量为800万或1000万的改性非离子型聚丙烯酰胺分别与相对分子质量为1 000万的聚丙烯酸钠混合对加速铝酸钠溶液种分分解的效果比未改性的效果好,与无添加剂相比其种分分解速率分别提高1.64%和2.53%,比加入未改性有机添加剂的种分分解速率分别提高0.42%和0.45%;35%和50%改性阳离子型聚丙烯酰胺分别和相对分子质量为1000万的聚丙烯酸钠混合可显著提高种分分解速率,与无添加剂相比,分解速率分别提高3.52%和5.61%,比加入未改性有机添加剂的种分分解速率分别提高0.88%和1.55%,且添加剂的相对分子质量越大,其效果越好.
Organic additives polyacry lamide was modified by chemical reactions, the high yield of non-ionic polyacry lamide grafted by hydroxylamine was obtained in the solution of strong electrolyte under the condition of temperature 80 ℃, pH = 11, proportion of hydroxylamine to amide 1 : 2. The decomposition experiment was carried out as follows: after caustic aluminate solution was added to the stainless reactor, the mixed organic additives were diluted and mixed with seeds, and then added to the reactor. It is found that when the mixed additives of the modified non-ionic polyacry lamide with relative molecular mass of 8X 106 or 1× 10^7 and sodium polyacrylic acid with relative molecular mass of 1 ×10^7 were added in the sodium aluminate solutions, the precipitation ratios are increased by 1.64% and 2.53% respectively in contrast to no additives added, and also the precipitation ratios are increased by 0. 42% and 0. 45% in contrast to unmodified mixed additives, when the mixed additives of 35 % or 50 % modified positive polyacry lamide and sodium polyacrylic acid with relative molecular mass of 1 ×10^7 are added in the sodium aluminate solutions, the precipitation ratios are increased by 3.52 % and 5.61% respectively in contrast to no additives added, and also the precipitation ratios are increased by 0.88 % and 1.55 % in contrast to unmodified mixed additives. And the more the relative molecular mass, the better the effect of mixed additives.