Trichloroacetic acid methylene chloride

The rate of stripping or the stripabiUty on cataly2ed urethane and epoxy resin finishes can be increased by adding formic acid, acetic acid, and phenol. Sodium hydroxide, potassium hydroxide, and trisodium phosphate [10101-89-0] may be added to the formula to increase the stripabiUty on enamel and latex paints. Other activators include oleic acid [112-80-17, trichloroacetic acid [76-85-9], ammonia, triethanolamine [102-71-6], and monoethyl amine. Methylene chloride-type removers are unique in their abiUty to accept cosolvents and activators that allow the solution to be neutral, alkaline, or acidic. This abihty gready expands the number of coatings that can be removed with methylene chloride removers. 

Future work. With modifiers less polar than methanol, low concentrations of some additives dramatically increase the apparent solvent strength of ternary mixtures, as shown in Figure 8. Thus, 20 % methylene chloride containing 1.0 % trichloroacetic acid (TCA) produces an apparent solvent strength greater than pure methanol (compare Figures 4 8). 

Test C About 25 mg of the acid sample is dissolved in 15 mL of methylene chloride. The solution is examined in ultraviolet light at 365 nm to exhibit a strong greenish-yellow fluorescence. Carefully add 0.5 mL of a saturated solution of trichloroacetic acid dropwise and examine under ultraviolet light at 365 nm. The solution does not exhibit fluorescence. 

Austin suggested organic solvents containing acids such as chloroethanol, sulfuric acid and trichloroacetic acid (TCA) for the direct dissolution of chitin in 1975 [23]. A filament was extmded from the spin solution made with chitin in a mixture of 40% TCA, 40% chloral hydrate, and 20% methylene chloride. The filaments were solidified in the coagulating bath containing acetone, neutralized with potassium hydroxide (KOH) in 2-propanol followed by washing in deionized water, and, then, cold drawn. Other solvent systems for chitin have been proposed [24]. However, they require fairly drastic conditions to dissolve chitin and some are very corrosive or expensive. It is hard to maintain the chitin molecule without depolymerization during the dissolution process. 

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