表面活性剂图书之三.pdfVIP

3.4.6. SULFO-CARBOXYLIC COMPOUNDS These compounds display at least 2 hydrophilic groups: the sulfonate group and one (or two) carboxylic group(s) as carboxylate or ester. The monocarboxylic compounds are not very important in practice, and the best known product of this category is the sodium lauryl sulfo- acetate which is found in tooth pastes, shampoos, cosmetics and slightly alkaline soaps. NaOOC-(CH ) -SO -Na+ 2 11 3 C18 compounds are used in butter and margarine as anti-splattering agents, because they are able to fix the water in food emulsions so that the evaporation is not explosive when they are heated in a pan. On the other hand sulfo-dicarboxylic compounds, such as sulfosuccinates and sulfosuccinamates are well know and used in many applications. Succinic acid is a diacid which should be named: 2-butene 1,4 dicarboxylic. The diester (succinate) is produced by direct reaction of maleic anhydride with an alcohol, followed by a sulfonation. O O C C O + 2 R-OH Æ ROOC-CH -CH Æ ROOC-CH -CH-COOR 2 2 2 HC CH -COOR SO3-Na+ succinate sulfosuccinate O O C C O R 1 R 1 + NH Æ HOOC-CH=CH-CON Æ ZOOC-CH -CH-CONR 1R2 2 HC CH R 2 R 2 SO3-Na+ succinamic acid sulfosuccinamate where Z represents a sodi