Copolymer of anhydride of unsatd. carboxylic acid and cyclic ketene - used as dispersant, esp. in washing compsn., or support for active material

摘要

Copolymer contains (a) at least 12 wt. % of a mono-or poly-unsatd. carboxylic acid anhydride and (b) a ketone deriv. radically polymerising by ring opening. Pref. (a) the components are anhydrides of mono- or di-carboxylic acids, esp. anhydrides of methacrylic, maleic and/or itaconic acids. (b) the components are ketene monothio or aminoacetals or derivs. of formula (I), X = O, S or NR1, R = 2-7C alkylene opt. by C1 or 1-4C alkoxy, R1-1-8C alkyl. Claimed ketene derivs. are 2-methylenedioxepan-1, 3;2-methylene-dioxolan-1, 3;, N-R1-2-methylene-1, 3-hexahydrooxazepin, N-R1-2-methylene-oxazolidin-1,3-2-methyleneoxathiepan-1,3 or 2-methyleneoxathiolan-1, 3. The copolymer contains (a) 97.5-25% of an anhydride of a monoethylenically unsatd. mono or di-carboxylic acid, (b) 2.5-75% of the ketene deriv. and (c) 0-20% of another, copolymerisable, monomer and has K value of 8-100 as the water-sol. salts. USE - Copolymers are used, as water-sol. salts as dispersants and as soil-dispersants in washing compsns. (claimed). They are also used as supports for active materials, forming bio-erodible, slow-acting systems. The washing and cleaning compsn. are esp. low-phosphate or phosphate-free (pref).