Polyacrylamide flocculent synthesis

The process of formation of polyacrylamide flocculant on the basis of acrylonitrile and sulphuric acid in one stage was investigated. The required properties of flocculant can be obtained as result of achievement of the optimal rates ratio of reactions of polymerization and hydrolysis, which proceeds in the synthesis conditions simultaneously. 

Finally, the preparation of nonaqueous polymer dispersions has been used as a technique for polymer production. Process advantages such as the use of lower temperatures for polyamide and polyester synthesis can be obtained [3.70]. Products such as synthetic elastomers can be obtained in powder form [3.104]. The fine particulate form of dispersions of water-soluble polymers (e.g., polyacrylamide) offers a convenient route to aqueous solutions of polymeric flocculants and thickeners [3.105]. 

S. Mishra, G. Sen, G.U. Rani, and S. Sinha, Microwave assisted synthesis of polyacrylamide grafted agar (Ag-g-PAM) and its apphcation as flocculant for wastewater treatment, Int. J. 

Sen G, Mishra S, Rani GU, Rani P, Prasad R. Microwave initiated synthesis of polyacrylamide grafted Psyllium and its application as a flocculant. Int J Biol Macromol 2012 50 369-375. 

Rani P, Sen G, Mishra S, Jha U. Microwave assisted synthesis of polyacrylamide grafted gum ghatti and its application as flocculent. Carbohydr Polym 2012 89 275-281. 

A variety of commercially useful polyacrylamides obtained via the derivatization of polyacrylamide are reported. These include the formation of anioiuc polyacrylamide through hydrolysis [17], the synthesis of sulfomethylated derivatives from the reaction of polyacrylamide with formaldehyde and sodium bisulfate [18], the formation of aminomethylated polyacrylamide from the reaction of polyacrylamide with formaldehyde and dimethylamine (Mannich reaction) [19], and the generation of various derivatives by transamidation reactions including hydroxamated polyacrylamides used as a flocculant in the Bayer process [20, 21]. Huorescent polyacrylamide or polyacrylate derivatives, useful for monitoring polymer concentration in industrial applications, are obtained by the incorporation of a small amount of fluorescent monomer into the polymer backbone [22]. 

Many creative methods for modifying polyacrylamides formed by inverse emulsion polymerization for enhanced activity in target applications are found in the patent literature. Flesher reported the synthesis of a cross-linked, water swellable polymer, useful for flocculation in high shear dewatering devices, by adding a small amount of a divinylic cross-linking agent [10]. 

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