Abstract: The invention relates to the use of copolymers of the average formula ##STR1## in which R is an alkyl radical with 1 to 4 carbon atoms or a hydrogen radical;n=10 to 200;m=1 to 25;o=1 to 100 with the proviso that o is not less than m, and 3 o is less than n in the average molecule;p=7 to 17; andwherein the molecular weight of the (C.sub.2 H.sub.4 O--).sub.x (C.sub.3 H.sub.6 O--).sub.y R radical is 250 to 2,000 with x and y being selected so that the weight ratio of oxyethylene to oxypropylene is 100:0 to 20:80, as emulsifiers for the preparation of W/O emulsions, whose oily phase consists of or contains silicone oil.