Abstract: The production of SiOC-bonded, linear polydimethylsiloxane-polyoxyalkylene block copolymers comprising repeating (AB) units by reaction of polyether diols with trifluoromethanesulfonic acid-acidified, equilibrated ?,?-diacetoxypolydimethylsiloxanes is described, wherein the reaction is undertaken by adding a solid, liquid or gaseous base, optionally using inert solvents.

Abstract: Process for producing SiOC-bonded, linear polydimethylsiloxane-polyoxyalkylene block copolymers comprising repeating (AB) units, comprising pretreating acidified, end-equilibrated ?,?-diacetoxypolydimethylsiloxanes with a base and reacting the ?,?-diacetoxypolydimethylsiloxanes resulting therefrom with polyether diols in the presence of a solid, liquid or gaseous base, optionally using inert solvents.

Abstract: Processes are described for purifying acidic, preferably superacidic, in particular trifluoromethanesulfonic acid-acidified, end-equilibrated acetoxysiloxanes, wherein the acidic, preferably superacidic, in particular trifluoromethanesulfonic acid-acidified, acetic anhydride-containing and optionally acetic acid-containing equilibrated, preferably end-equilibrated acetoxysiloxane, which is optionally dissolved in an inert solvent, is contacted with a base, the precipitate is filtered off thereafter and then the filtrate obtained is optionally purified by distillation.

Abstract: Branched SiOC-linked polyethersiloxanes have the following formula (I) where R1 is an alkyl radical having 1 to 4 carbon atoms or a phenyl radical, but preferably 90% of the radicals R1 are methyl radicals; b has a value of from 1 to 10; a has a value of from 1 to 200, preferably 10 to 100, a value of from 3 to 70 when b is ?1 and ?4, or a value of from 3 to 30 when b is >4; and R2 denotes identical or different polyether radicals, but at least one radical R2 is a structural element radical of formula (II): where p=at least 2, preferably p=2-6, particularly preferably p=3.

Abstract: Process for producing SiOC-bonded, linear polydimethylsiloxane-polyoxyalkylene block copolymers comprising repeating (AB) units, comprising pretreating acidified, end-equilibrated ?,?-diacetoxypolydimethylsiloxanes with a base and reacting the ?,?-diacetoxypolydimethylsiloxanes resulting therefrom with polyether diols in the presence of a solid, liquid or gaseous base, optionally using inert solvents.

Abstract: Process for producing PU foams by reacting at least one polyol component with at least one isocyanate component in the presence of one or more catalysts that catalyze the isocyanate-polyol and/or isocyanate-water and/or isocyanate trimerization reactions, and optionally one or more chemical or physical blowing agents, with use of SiOC-linked, linear polydialkylsiloxane-polyoxyalkylene block copolymers having repeat (AB) units, obtainable through the reaction of polyether diols with equilibrated ?,?-diacetoxypolydialkylsiloxanes, wherein a sufficient amount of the SiOC-linked, linear polydialkylsiloxane-polyoxyalkylene block copolymers having repeat (AB) units is added such that the proportion by mass of said component based on the finished PU foam is from 0.0001% to 10% by weight, preferably 0.01% to 6% by weight, especially 0.05% to 5% by weight.

Abstract: The production of SiOC-bonded, linear polydimethylsiloxane-polyoxyalkylene block copolymers comprising repeating (AB) units by reaction of polyether diols with trifluoromethanesulfonic acid-acidified, equilibrated ?,?-diacetoxypolydimethylsiloxanes is described, wherein the reaction is undertaken by adding a solid, liquid or gaseous base, optionally using inert solvents.

Abstract: The production of SiOC-bonded, linear polydimethylsiloxane-polyoxyalkylene block copolymers comprising repeating (AB) units by reaction of polyether diols with trifluoromethanesulfonic acid-acidified, equilibrated ?,?-diacetoxypolydimethylsiloxanes is described, wherein the reaction is undertaken by adding a solid, liquid or gaseous base, optionally using inert solvents.

Abstract: Processes are described for purifying acidic, preferably superacidic, in particular trifluoromethanesulfonic acid-acidified, end-equilibrated acetoxysiloxanes, wherein the acidic, preferably superacidic, in particular trifluoromethanesulfonic acid-acidified, acetic anhydride-containing and optionally acetic acid-containing equilibrated, preferably end-equilibrated acetoxysiloxane, which is optionally dissolved in an inert solvent, is contacted with a base, the precipitate is filtered off thereafter and then the filtrate obtained is optionally purified by distillation.

Abstract: Branched SiOC-linked polyethersiloxanes have the following formula (I) where R1 is an alkyl radical having 1 to 4 carbon atoms or a phenyl radical, but preferably 90% of the radicals R1 are methyl radicals; b has a value of from 1 to 10; a has a value of from 1 to 200, preferably 10 to 100, a value of from 3 to 70 when b is ?1 and ?4, or a value of from 3 to 30 when b is >4; and R2 denotes identical or different polyether radicals, but at least one radical R2 is a structural element radical of formula (II): where p=at least 2, preferably p=2-6, particularly preferably p=3.

Abstract: The production of SiOC-bonded, linear polydimethylsiloxane-polyoxyalkylene block copolymers comprising repeating (AB) units by reaction of polyether diols with trifluoromethanesulfonic acid-acidified, equilibrated ?,?-diacetoxypolydimethylsiloxanes is described, wherein the reaction is undertaken by adding a solid, liquid or gaseous base, optionally using inert solvents.

Abstract: A process for preparing SiC-bonded polyethersiloxanes by precious metal-catalysed addition of olefinically unsaturated polyethers onto siloxanes having SiH groups is described, wherein, prior to commencement of reaction, the siloxane having SiH groups is mixed with an olefinically unsaturated polyether and with a polyethersiloxane by stirring, and then contacted with a precious metal catalyst and optionally further additives, and the SiC bond formation reaction is conducted up to an SiH conversion, determined by gas-volumetric means, of at least 97%.

Abstract: A process for preparing SiC-bonded polyethersiloxanes by precious metal-catalysed addition of olefinically unsaturated polyethers onto siloxanes having SiH groups is described, in which, prior to commencement of reaction, the siloxane having SiH groups is mixed together with a polyethersiloxane, preferably by stirring, and then, in a second step, this preliminary mixture is contacted with an olefinically unsaturated polyether and with a precious metal catalyst and optionally further additives, preferably with further stirring, and the SiC bond formation reaction is conducted up to an SiH conversion, determined by gas-volumetric means, of at least 97%.

Abstract: A process for preparing SiC-bonded polyethersiloxanes by precious metal-catalysed addition of olefinically unsaturated polyethers onto siloxanes having SiH groups is described, wherein, prior to commencement of reaction, the siloxane having SiH groups is mixed with an olefinically unsaturated polyether and with a polyethersiloxane by stirring, and then contacted with a precious metal catalyst and optionally further additives, and the SiC bond formation reaction is conducted up to an SiH conversion, determined by gas-volumetric means, of at least 97%.

Abstract: A process for preparing SiC-bonded polyethersiloxanes by precious metal-catalysed addition of olefinically unsaturated polyethers onto siloxanes having SiH groups is described, in which, prior to commencement of reaction, the siloxane having SiH groups is mixed together with a polyethersiloxane, preferably by stirring, and then, in a second step, this preliminary mixture is contacted with an olefinically unsaturated polyether and with a precious metal catalyst and optionally further additives, preferably with further stirring, and the SiC bond formation reaction is conducted up to an SiH conversion, determined by gas-volumetric means, of at least 97%.

Abstract: The invention relates to a process for the preparation of SiOC-linked, linear polydimethylsiloxane-polyoxyalkylene block copolymers having (AB) repeat units, via reaction by methods known per se of polyetherdiols with a stoichiometric excess of ?,?-dihydropolydimethylsiloxanes, in the presence of one or more compounds of elements of main group 13 and/or of transition group 3 as catalyst, which comprises, after completed reaction of the alcohol component, continuing the reaction until no remaining ?Si(H) groups are detectable by a gas-volumetric method, and also to the compounds thus prepared, and to their use as surfactant additives for the production of polyurethane ether foams.

Abstract: The invention relates to a process for the preparation of SiOC-linked, linear polydimethylsiloxane-polyoxyalkylene block copolymers having (AB) repeat units, via reaction of one or more polyetherdiols with a stoichiometric excess of ?,?-dihydropolydimethylsiloxanes and at least one tertiary amine as catalyst, which comprises, after completed reaction of the alcohol component, continuing the reaction in the presence of small amounts of water until no remaining ?Si(H) groups are detectable by a gas-volumetric method.

Abstract: The invention provides linear polydimethylsiloxane-polyoxyalkylene block copolymers containing Si—C groups and carboxylic ester groups and having repeating (A1BA2B) units where A1 and A2 are two different polydimethylsiloxane units of the general formula (I) with a number of Si atoms N=(n+2) of 15?N?30 and NA1?NA2 and B is a unit of the formula (II) —CH2—CH2—(CH2)a—CO[O—CH2—CH(R)]c—O-[D-O]e—[—CH2—CH(R)—O]d—OC—(CH2)b—CH2—CH2— (II) where R independently at each occurrence is H, —CH3 or —C2H5, a and b independently of one another are 0 to 20, c and d independently of one another are values?1, e is 0 or 1 and D is a hydrocarbon radical having 2 to 10 C atoms, the overall molar weight of the unit of the formula II being from 600 to 10 000 g/mol, with the proviso that the average mixed molar weight of the polydimethylsiloxane units (A1+A2) is from >1665 to <1998 g/mol and the fraction of [O—CH2—CH(R)] with R?H is >0% to ?50% by weight, based on the overall weight of [O—CH2—CH(R)] in B, a process for p

Abstract: The invention therefore relates to a process for preparation of SiOC-linked, linear (AB)d polydimethylsiloxane-polyoxyalkylene block copolymers of the general formula [(R2SiO)x(CnH2nO)y]d, in which R are monovalent C1-C18, preferably C1-C4, hydrocarbon radicals, n is a number from 2 to 4, preferably 2 or 3, x ?5, y ?10, d ?3, via reaction of aminosiloxanes having primary amino groups with polyoxyalkylenediols, which comprises concomitant use of one or more tertiary amines as catalyst.

Abstract: The invention provides linear polydimethylsiloxane-polyoxyalkylene block copolymers containing Si—C groups and carboxylic ester groups and having repeating (A1BA2B) units where A1 and A2 are two different polydimethylsiloxane units of the general formula (I) with a number of Si atoms N=(n+2) of 15?N?30 and NA1?NA2 and B is a unit of the formula (II) —CH2—CH2—(CH2)a—CO[O—CH2—CH(R)]c—O-[D-O]e—[—CH2—CH(R)—O]d—OC—(CH2)b—CH2—CH2— (II) where R independently at each occurrence is H, —CH3 or —C2H5, a and b independently of one another are 0 to 20, c and d independently of one another are values ?1, e is 0 or 1 and D is a hydrocarbon radical having 2 to 10 C atoms, the overall molar weight of the unit of the formula II being from 600 to 10000 g/mol, with the proviso that the average mixed molar weight of the polydimethylsiloxane units (A1+A2) is from >1665 to <1998 g/mol and the fraction of [O—CH2—CH(R)] with R?H is >0% to ?50% by weight, based on the overall weight of [O—CH2—CH(R)] in B, a process fo