Sulfoethyl acrylamide

Copolymers or terpolymers of acrylic acid, which contain from 5 to 50 mole-percent of sulfoethyl acrylamide, acrylamide and sulfoethyl acrylamide, ethyl acrylate and sulfoethyl acrylamide, acrylamide and sulfophenyl acrylamide, and acrylamide and sulfomethyl acrylamide, are claimed to be calcium-tolerant deflocculants for drilling fluids [704]. In general, 0.1 to 2 lb of polymer per barrel of drilling fluid is sufficient to prevent flocculation of the additives in the drilling fluid. 

General. Aqueous solutions of hydrophilic monomers were emulsified in xylene using water-in-oil emulsifiers, and polymerized using oil-soluble initiators. Typical hydrophilic monomers were sodium p-vinylbenzene sulfonate, sodium vinylbenzyl sulfonate, 2-sulfoethyl acrylate, acrylic acid, acrylamide, vinylbenzyl-trimethylammonium chloride, and 2-aminoethyl methacrylate hydrochloride. Typical oil-soluble initiators were benzoyl and lauroyl peroxides. In some cases, water-soluble potassium persulfate was used, both separately and in mixtures with oil-soluble peroxides. Of the water-in-oil emulsifiers, one of the most effective was Span 60 (technical sorbitan monostearate. Atlas Chemical Industries, Inc.). 

Nevertheless, if the oilfield can be preflushed by fresh water, satisfactory results can be obtained with hydrolyzed polyacrylamides. On the other hand, poly(acrylamide-co-sodium-2-sulfoethyl-methacrylate)... 

This hydroxamation reaction occurs under alkaline conditions (131-133). Carboxyl groups can be produced because of the hydrolysis of the amide (131, 132). Acrylamide polymers can also be reacted with primary amines such as 2-aminoethanesulfonic acid (taurine) [107-35-7] at high temperature and acid pH to yield N-substituted copolymers containing sulfoethyl groups (134). 

Carboxyethyl cellulose (CEC) obtained by reaction of acrylamide with alkaline cellulose and subsequent - hydrolysis. Properties are similar to CMC. Other cellulose ethers are sodium 2-sulfoethyl cellulose (SEC) and phosphonomethyl cellulose (PMC). The mixed ether of the latter with hydro-xyethylated cellulose (HEPMC) shows unusual gelling properties with multivalent cations at different pH values. 

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