Wacker-chemie Gmbh

Erich Brunner

Bernward Deubzer

Konrad Sallersbeck

Jurgen Burkhardt

Herman Wilhelm

Hydrophilic, crosslinked organopolysiloxanes are obtained from the polymerization of hydroxyalkylmethacrylate and/or hydroxalkylacrylate in the presence of an organopolysiloxane containing at least 40 mol percent of monoorganosiloxane units. These hydrophilic, crosslinked, modified organopolysiloxanes are prepared by polymerizing hydroxyalkylmethacrylate and/or hydroxyalkylacrylate in the presence of free radical initiators and an organopolysiloxane containing at least 40 mol percent of monoorganosiloxane units which can be crosslinked or has been crosslinked by the condensation reaction in the presence of a condensation catalyst, the amount and type of condensation catalyst and/or catalytic system, including the inhibitor for the polymerization of the hydroxyalkylmethacrylate and/or hydroxyalkylacrylate, is selected so that the crosslinking of the organopolysiloxane which is substantially uniformly distributed in the hydroxyalkylmethacrylate and/or hydroxyalkylacrylate is initiated and preferably completed before the polymerization of the hydroxyalkylmethacrylate and/or hydroxyalkylacrylate is completed.

Hydrophilic, crosslinked, modified organopolysiloxanes and process for

Impregnated wood containing a polymer which is produced in the wood from the polymerization of a monomer and/or prepolymer having aliphatic multiple bonds and crosslinked organopolysiloxanes. The polymer impregnated wood is prepared by impregnating the wood with a mixture containing a monomer and/or prepolymer containing aliphatic multiple bonds which is capable of free radical polymerization and a crosslinkable organopolysiloxane and thereafter the monomer and/or prepolymer is polymerized and the organopolysiloxane is crosslinked in the wood.

Polymer impregnated wood and process for preparing the same

A process for preparing plastic wood which comprises impregnating wood with a mixture containing (1) an organopolysiloxane having groups which are capable of condensation and/or containing SiC-bonded alkenyl group having an average molecular weight of at least 500 when the organopolysiloxane contains from 0.5 to 1.89 SiC-bonded organic radicals for each silicon atom and when the organopolysiloxane (1) contains from 1.90 to 2 SiC-bonded organic radicals for each silicon atom, then the average molecular weight is at least 20,000 and (2) an organic silicon compound having at least three groups which are capable of condensation and/or atoms capable of condensation and a maximum of 10 silicon atoms per molecule; and other substances if desired; and thereafter crosslinking the organopolysiloxane (1) having groups capable of condensation and/or containing SiC-bonded alkenyl groups, which is present in the wood.

Process for the preparation of impregnated wood

Organopolysiloxane compositions which are stable at room temperature, but are curable when subjected to elevated temperatures comprising (1) an organosilicon compound containing Si-bonded hydrogen, (2) an organosilicon compound containing aliphatic multiple bonds, (3) a catalyst capable of promoting the addition of Si-bonded hydrogen to the aliphatic multiple bonds and (4) an organic compound as an additive containing at least one group of the formula ##STR1## in which the additive inhibits curing at room temperature.

Thermosetting organopolysiloxane compositions

A process for preparing cross-linked, modified organopolysiloxanes which comprises polymerizing at least one monomer having at least one aliphatic multiple bond in the presence of a free radical initiator and at least one cross-linked organopolysiloxane containing at least 40 mol percent of monoorganosiloxane units. When the organopolysiloxane is not crosslinked, then the polymerization of the monomer having at least one aliphatic multiple bond is conducted in the presence of an organopolysiloxane having at least 40 mol percent mono-organosiloxane units, and a free radical initiator and a catalyst which promotes cross-linking of the organopolysiloxane.

Growing community of inventors

Gmunden, Austria

Erich Brunner