Abstract: The invention relates to a process for preparing silanes or siloxanes having carboxyl functionalities, wherein a hydrogen silane or hydrogen siloxane compound is reacted with a tertiary butyl ester having an olefinic double bond and the sil(ox) ane-bonded tertiary butyl ester group is subsequently converted into the corresponding carboxyl group with elimination of isobutene.

Abstract: A method of defoaming diesel fuel by adding an organofunctionally modified polysiloxane of the general Formula I ##STR1## wherein R.sup.1 are alkyl groups with 1 to 4 carbon atoms or aryl groups with the proviso that at least 80% of the R.sup.1 groups are methyl groups,R.sup.2 are the same or different in the molecule30 to 90% of R.sup.2 having the same meaning as R.sup.1, and70 to 10% of R.sup.2 consisting of a mixture of R.sup.2A and R.sup.2B groups which differ in polarity,is described. The inventive polysiloxane is added in an amount of 0.5 to 50 ppm, based on the diesel fuel.

Abstract: The invention relates to a method for the synthesis of organopoiysiloxanes of the general formula ##STR1## which contains cyclic carbonate groups. The inventive compounds have a high polarity, can be synthesized easily and, because of their compatibility with polar media, find use as additives for dispersion paints or lacquers and for coating the surfaces of pigments and fillers.

Abstract: Organopolysiloxanes, which terminally, laterally or both have at least one group of the formula ##STR1## well as at least one acrylate group, linked over a bridge element to this group, is obtained by hydrosilylation of organopolysiloxanes with at least one SiH group by compounds, which have at least two acrylate groups, in equimolar amounts at a temperature of 60.degree. to 130.degree. C. in presence of rhodium catalysts. The rhodium catalysts cause a 1,2 addition to take place during the addition reaction between polyacrylates and hydrogen siloxanes.

Abstract: An abhesive coating composition is based on an organopolysiloxane having radiation-curing (meth)acrylate ester groups, which contains an additive that affects the degree of abhesiveness, the additive being obtained by the reaction of an MQ resin with a polysiloxane containing (meth)acrylate ester groups.

Abstract: Polysiloxanes of the general formula ##STR1## which contain at least one sulfatohexyl group linked by an Si--C bond are prepared wherein R.sup.1 is a methyl or phenyl group with the proviso that at least 90% of the R.sup.1 groups are methyl groups, R.sup.2 either is identical with R.sup.1 or is --(CH.sub.2).sub.6 --OSO.sub.3.sup.-.M.sup.+, M.sup.+ being an alkali, 1/2 alkaline earth or optionally an alkyl-substituted ammonium ion, R.sup.3 is identical with R.sup.1 or R.sup.2, with the proviso that at least one R.sup.2 or R.sup.3 group in the average molecule is a --(CH.sub.2).sub.6 --OSO3.sup.-.M.sup.+ group, "a"=0 to 5 and b=0 to 5. A method for the synthesis of these compounds and their use as hydrolysis-resistant surfactants is also described.