Graft copolymers of organopolysiloxanes as free radical macroinitiators

US5523365A · kind A · utility

Assignee

• Wacker Chemie AG · DE

Inventors

• Michael Geck · Burghausen, DE
• Jochen Dauth · Burghausen, DE
• Bernward Deubzer · Burghausen, DE
• Helmut Oswaldbauer · Stubenberg, DE
• Manfred Schmidt · Krefeld, DE
• Frank Baumann · Mehring, DE

Key dates

• Filing date: Oct 11, 1994
• Grant date: Jun 4, 1996
• Expiry date: Oct 11, 2014

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G77/48
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention relates to crosslinked organopolysiloxanes which contain groups which form free radicals and are built up from units of the formula EQU [R.sub.a Si(O.sub.(3-a)/2)-R.sup.1 -X-(R.sup.1 -Si(O.sub.(3-a)/2)).sub.b R.sub.a ] (1), in which PA0 X is a radical from the group consisting of --N.dbd.N--, --O--O--, --S--S-- and --C(C.sub.6 H.sub.5).sub.2 --C(C.sub.6 H.sub.5).sub.2 --, and PA0 R is monovalent SiC-bonded, optionally substituted C.sub.1 - to C.sub.18 -hydrocarbon radicals, PA0 R.sup.1 is divalent SiC-bonded, optionally substituted C.sub.1 - to C.sub.18 -hydrocarbon radicals which can be interrupted by divalent radicals, bonded to carbon atoms on both sides, from the group consisting of --O--, --COO--, --OOC--, --CONR.sup.2 --, --NR.sup.2 CO-- and --CO--, PA0 R.sup.2 is a hydrogen atom or a radical R, PA0 a has the values 0, 1 or 2 and PA0 b has the values 0 or 1, and further organosiloxane units. The organopolysiloxanes are used as free radical macroinitiators for grafting polymerization of ethylenically unsaturated monomers.