Industrial solvents acetamide

As a dipolar solvent, acetamide finds many uses as a solvent for both inorganic and organic compounds. The solvency has led to widespread uses in industry including applications in cryoscopy, soldering, and the textile industry. The neutral and amphoteric characteristics allow its use as an antacid in the lacquer, explosives, and cosmetics industries. Its hygroscopic properties make it useful as a plasticizer in coatings, fixtures, cloth, and leather, and as a hum-ectant for paper. It is also a raw material in organic synthesis of methylamine and thioacetamide and as an intermediate in preparation of medicines, insecticides, and plastics. 

The first industrial facility dates from 1965. Others have followed suit, but they are essentially built at locations belonging to Union Carbide. The process employs dimethyl-acetamide, containing 10 per cent weight water, as solvent In its latest version, it comprises a single absorption/regeneration step. 

Polyvinylpyrrolidone (PVP) is a synthetic polymer derived from the Reppe chemistry and is widely used in the pharmaceutical, personal care, cosmetic, agriculture, beverage, and many industrial applications. PVP is a polar and amorphous polymer which is soluble in water and some organic solvents, such as alcohols, chlorinated hydrocarbons, dimethyl formamide, dimethyl acetamide, and V-methyl pyrrolidone. 

Isophthaloyl dichloride and m-phenylene diamine dihydrochloride with trimethylamine hydrochloride as catalyst, dimethylacetamidc as solvent, and sodium hydroxide as HCl scavenger produce a polyamide by polycondensation that can only be spun from its solution in dimethyl acetamide after addition of 3% CaCl2 because of the high melting temperature of 375° C for the polyamide. The nondyeable yarn and fibers can be used for industrial purposes, for example as filter cloths for hot gases or for paper for electrical insulation. 

Polyvinylidene fluoride is used extensively in the electronics industry because of its piezoelectric and pyroelectric properties. Only two room temperature solvents, n-methylpyrrolidone and dimethyl acetamide, have been found. Still-wagon (37) used n-methylpyrrolidone as the solvent for low-angle laser light-scattering measurement because of the larger refractive index increment value (dn/dc) in that solvent. No SEC work in these solvents was mentioned. 

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