Graft Polymerization of Acrylamide and 2-Acrylamido-2-methylpropanesulfonic Acid onto Starch
Graft Polymerization of Acrylamide and 2-Acrylamido-2-methylpropanesulfonic Acid onto Starch
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DOI：
10.1002/app.1979.070240909
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发表时间：
1979-11
影响因子：
3
通讯作者：
G. F. Fanta;R. C. Burr;W. Doane
中科院分区：
文献类型：
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作者：
G. F. Fanta;R. C. Burr;W. Doane
以丙烯酰胺和2-丙烯酰胺基-2-甲基丙磺酸（AASOsH）为单体，采用钴-60辐照法在淀粉上进行接枝聚合，并测定了产物的吸水率和水溶性。当预胶化小麦淀粉和两种单体的水溶液被同时照射（同时照射条件）时，单体向聚合物的转化几乎是定量的。当丙烯酰胺与AASOsH的质量比为9：1 ~ 1：3时，淀粉与总单体的质量比相同时，产物的吸水率较高。这些聚合物的水溶性均在50%以上。当单独接枝聚合到淀粉上时，这两种单体都没有得到吸收性聚合物。尽管在总单体：淀粉比为2：5时也获得了高吸收性产品，但1：5和更低的比例得到了吸收性差的产品。在接枝聚合之前用氢氧化钠中和AASOsH，大大降低了最终产物的水溶性和吸收性。与颗粒状淀粉的反应也在同时照射下进行，总单体：淀粉比为2：5并且两种单体的重量相等。单体向聚合物的转化再次接近定量。为了从该粒状产物获得良好的吸水性，必须首先用碱中和AAS 03 H部分，然后将聚合物分散在热水中，最后干燥所得的水分散体。通过将预辐照淀粉加入丙烯酰胺和AAS 03 H的水溶液中，也获得了具有良好吸水性的接枝共聚物，尽管仅实现了单体向聚合物的部分转化。通过用水或1%氯化钠溶液萃取，将来自各种接枝聚合的选定产物分级。测定所得级分的合成聚合物含量和每种聚合物的合成部分中AAS 03 H的百分比。一些合成的聚合物的Mn也确定后，通过酶水解除去碳水化合物。
Mixtures of acrylamide and 2-acrylamido-2-methylpropanesulfonic acid (AASOsH) were graft polymerized onto starch by cobalt-60 irradiation, and the water absorbency and water solubility of the resulting products were determined. The conversion of monomers to polymer was nearly quantitative when pregelatinized wheat starch and a water solution of the two monomers were si multaneously irradiated (simultaneous irradiation conditions). Products with high \vater absorbency were obtained with equal weights of starch and total monomers when acrylamide:AASOsH ratios ranged from 9:1 to 1:3. Water solubility of these polymers was over 50%. Neither of the two monomers gave absorbent polymers when graft polymerized individually onto starch. Although highly absorbent products were also obtained at a total monomer:starch ratio of 2:5, ratios of 1:5 and lower gave products with poor absorbency. Neutralization of AASOsH with sodium hydroxide before graft polymerization drastically reduced both the water solubility and absorbency of the final products. A reaction with granular starch was also carried out under simultaneous irradiation with a total monomer:starch ratio of 2:5 and with equal weights of the two monomers. Conversion of monomers to polymer was once again nearly quantitative. To obtain good water absorbency from this granular product, it was necessary to first neutralize the AAS03H portion with alkali, then disperse the polymer in hot water, and finally dry the resulting water dispersion. Graft copolymers with good water absorbency were also obtained by adding preirradiated starch to a water solution of acrylamide and AAS03H, although only partial conversions of monomers to polymer were realized. Selected products from the various graft polymerizations were fractionated by extractiqn with either water or a 1% solution of sodium chloride. The synthetic polymer content of the resulting fractions and the percentage of AAS03H in the synthetic portion of each polymer were determined. The M n of some of the synthetic polymers was also determined after removal of carbohydrate by enzymatic hydrolysis.