14 декабря, 2015 
Pokraskin 4.4.3.1 Chlorinated hydrocarbons
Chlorinated hydrocarbons have higher solvency than corresponding hydrocarbons for most resins and polymers used in coatings. They are miscible with many other types of organic solvents, but are insoluble in water. Non-flammability and high specific gravity are unique characteristics of this class of solvents. In recent years, their use in coatings has been almost negligible due to environmental and health reasons, but solvents such as dichoromethane were long used in paint removers due to their very strong solvency and fast evaporation rate. Chlorinated hydrocarbons have also been used in metal pretreatment for degreasing purposes.
4.4.3.2 N-methyl-2-pyrrolidone
N-methyl-2-pyrrolidone (Figure 4.6) is a cyclic amide with very strong solvency, high specific gravity, high flash point and low order
of toxicity. It is completely water soluble and reported to be biodegradable. In the coating industry, N-methyl-2-pyrrolidone, an apro — tic polar solvent, is especially used as a solvent in polyurethane dispersions and as an active solvent for urethane lacquers. It is also used in paint strippers, printing inks and occasionally as a coalescing agent in latex systems.
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