LOW CHLORIDE COMPOSITIONS OF OLEFINICALLY FUNCTIONALISED SILOXANE OLIGOMERS BASED ON ALKOXYSILANES

摘要

The invention relates to a composition comprising olefinically functionalized siloxane oligomers derived from olefinically functionalized alkoxysilanes and optionally alkoxysilanes functionalized with saturated hydrocarbons, and also, optionally, a tetraalkoxysilane, which have not more than one olefinic radical on the silicon atom, and whose chloride content is reduced, and also to processes for preparing them and to the use thereof.

主权项

1. A process for preparing a composition comprising olefinically functionalized siloxane oligomers, the process comprising reacting:
(i) an olefinically functionalized alkoxysilane of formula II,
A-Si(R2)x(OR1)3-x  (II), wherein A in formula II corresponds to an olefinic radical and is a linear, branched or cyclic alkenyl- or cycloalkenyl-alkylene-functional group having in each case 2 to 16 C atoms; R2 independently corresponds to a linear, branched or cyclic alkyl radical having 1 to 15 C atoms and x is 0 or 1; and R1 independently corresponds to a linear, branched or cyclic alkyl radical having 1 to 4 C atoms, (ii) in the presence of a hydrolysis and/or a condensation catalyst; (iii) with a defined amount of water in the presence of alcohol as solvent, to produce the siloxane oligomers; and (iv) substantially removing the hydrolysis alcohol and the solvent present; and (v) at least once during step (iv) or subsequently, further adding alcohol and carrying out removal; and (vi) wherein the total chloride content of the composition is less than or equal to 100 mg/kg; and (vii) the weight-average molecular weight (Mw) is greater than or equal to 410 g/mol.