| 摘要 |
Compsns. for dispersing hydrophobic particles in water comprise esters (I) prepd. by partial esterification of (a) polymerised fatty acids, polymerised resin acids and/or opt. polymerised fatty or rosin acid derivs. with (b) polyalkylene glycols or their monoesters or monoethers, provided that (I) have a residual acid value above 3. - Specifically component (a) is esp. crude tall oil (CTO) which has been polymerised (e.g. with BF3) and opt. distd. to remove volatiles. Component (a) may also be a residue obtd. by distn. of fatty acids from animal or vegetable fats or oils, or a prod. obtd. by Diels-Alder reaction of conjugated polyunsatd. fatty or rosin acids or by reaction of fatty or rosin acids with polyfunctional alcohols and/or carboxylic acids. Component (b) is pref. a polyethylene glycol (PEG) with a molecular wt. above 600, esp. 4000-10,000. (I) may be used in an amt. of 0.01-5 (pref. 0.3-1) wt.% for dispersing coal particles in water, esp. where the coal has a particle size of 1-200 microns. |
