Patent · US Expired

Basic condensation catalyst systems for siloxanes

US6313253A · kind A · utility

1Cited by

4References

20Claims

0Family size

Assignee

Wacker Chemie AG · DE

Inventors

Frank Baumann · Mehring, DE
Bernward Duebzer · Burghausen, DE
Chantal Delagnes · Cosne-Cours-sur-Loire, FR

Key dates

Filing date	Jan 6, 2000
Grant date	Nov 6, 2001
Priority date	—
Expiry date	Jan 6, 2020

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08K5/3467
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

The invention relates to a process for the condensation of compounds which carry silanol groups and have at least one unit of the general formula (III) EQU A.sub.c E.sub.d SiO.sub.(4-c-d)/2 (III) in which PA1 A is a hydroxyl group, PA1 E is an inert radical, PA1 c is 1, 2, 3 or 4 and PA1 d is 0, 1 or 2, PA1 with the proviso that c+d .ltoreq.4, in which higher molecular weight organosiloxane compounds are prepared by employing with a catalyst system comprising a catalyst which is chosen from basic alkali metal and alkaline earth metal compounds and a cocatalyst which is an at least bidentate chelating ligand and contains units of the general formula (I) EQU N--R.sup.1-- N (I) PA1 in which PA1 R.sup.1 is a divalent linear, cyclic and/or aromatic C.sub.1 -to C.sub.30 -hydrocarbon radical.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.