SILOXANE-OXYALKYLENE COPOLYMER SURFACTANT COMPOSITIONS

Siloxane-oxyalkylene copolymer surfactants in combination with alkyl esters of fatty acids are disclosed. Alkyl esters of fatty acids are represented by the general formula Z-COO-Y where Z is a saturated or unsaturated C10-24 alkyl or alkylene group and Y is typically a C1-6 alkyl, alkylene linear or branched group. The siloxane- oxyalkylene copolymer surfactants that are typically used with the fatty esters have the general formula MDxD'yM wherein M represents (CH3)3SiO1/2 or R(CH3)2SiO1/2, D represents (CH3)2SiO2/2, D' represents (CH3)RSiO2/2, and the value of x+y is from 50 to 220, and the ratio x/y is from 5 to 15 inclusive. In the above formulae for M and D', R is a polyether-containing substituent. The siloxane-oxyalkylene copolymer surfactants used in conjunction with the fatty ester contains a major fraction (60-80 wt.%) of siloxane- oxyalkylene with one pendant R typically defined as CnH2nO(C2H4O) a (C3H6O)bR' moieties having weight average molecular weights of from about 1400-2000 and wherein n is 1 -4 and typically 3, the values of "a" are in the range 12-22 and typically 16-20 and the values of "b" are in the range of 12-22 and typically 16-20, R' typically represent acyl group -C(0)CH3. The surfactant of the invention also contains a minor fraction of a siloxane-oxyalkylene copolymer (6-10 wt.%) having two pendant R typically defined as CnH2nO(C2H40)a(C3H60)bR' moieties having average molecular weights of about 1000- 3500 and wherein n is 1 -4 and typically 3, the values of "a" are in the range 8-40 and typically 10-35 and the values of "b" are in the range of 8-40 and typically 10-35, R' typically represent acyl group C(O)CH3. L'invention concerne des tensioactifs à base de copolymères de siloxane-oxyalkylène en combinaison avec des esters alkyliques d'acides gras. Les esters alkyliques d'acides gras sont représentés par la formule générale Z-COO-Y, où Z représente un groupe alkyle ou alkylène en C10-24, saturé ou insaturé et Y représente généralement un groupe alkyle, alkylène en C1-6 linéaire ou ramifié. Les tensioactifs à base de copolymères de siloxane-oxyalkylène qui sont généralement utilisés avec les esters gras présentent la formule générale MDxD'yM, dans laquelle M représente (CH3)3SiO1/2 ou R(CH3)2SiO1/2, D représente (CH3)2SiO2/2, D' représente (CH3)RSiO2/2 et la valeur de x + y est de 50 à 220 et le rapport x/y est de 5 à 15, valeurs extrêmes incluses. Dans les formules ci-dessus pour M et D', R représente un substituant contenant