Method for producing branched sih functional polysiloxanes and the use thereof for producing sic- and sioc-linked, branched organomodified polysiloxanes
AssigneeEvonik Goldschmidt GmbH
InventorsFrauke Henning, Wilfried Knott, Horst Dudzik
Life of this patent
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Abstract
The invention provides a process for preparing branched SiH-functional siloxanes by converting a mixture of one or more low molecular weight SiH-functional siloxanes, one or more low molecular weight SiH-free siloxanes and one or more trialkoxysilanes with addition of water and in the presence of at least one Brønsted-acidic catalyst, which is characterized in that the reaction is performed in one process step.
Claims16
A process for preparing a branched SiH-functional siloxane comprising:
- reacting a mixture of
- a) one or more SiH-functional siloxanes,
- b) one or more SiH function-free siloxanes, and
- c) one or more trialkoxysilanes,
- with addition of water and in the presence of at least one Brönsted-acidic catalyst to form a branched SiH-functional siloxane, wherein the reacting is performed in one process step.
A method for preparing organically modified polysiloxanes branched in the siloxane chain comprising:
- providing a hydrosiloxane with branching in the siloxane chain of general formula (I)
- in which
- n and n1 are each independently 0 to 500 and (n+n1) is <500,
- m and m1 are each independently 0 to 60 and (m+m1) is <60,
- k is 1 to 10,
- R is at least one radical from the group of linear, cyclic or branched, aliphatic or aromatic, saturated or unsaturated hydrocarbon radicals having 1 up to 20 carbon atoms,
- R1 is independently hydrogen or R,
- R2 is independently hydrogen, R or a heteroatom-substituted, functional, organic, saturated or unsaturated radical selected from the group of the alkyl, chloroalkyl, chloroaryl, fluoroalkyl, cyanoalkyl, acryloyloxyaryl, acryloyloxyalkyl, methacryloyloxyalkyl, methacryloyloxypropyl or a vinyl radical,
- R3 is independently hydrogen or R,
- with the proviso that at least one of the R1, R2 and R3 radicals is hydrogen, wherein said providing includes reacting a mixture of a) one or more SiH-functional siloxanes, b) one or more SiH function-free siloxanes and c) one or more trialkoxysilanes,
- with addition of water and in the presence of at least one Brønsted-acidic catalyst, wherein the reacting is performed in one process step;
- and
- reacting, partially or fully, said hydrosiloxane with at least one compound that has one double bond per molecule in the presence of a noble metal catalyst.
16-17. (canceled)
Dependencies are inferred from the claim text.