Wacker-chemie Gmbh

Ralph Ottlinger

Reinhard Jira

Willi Streckel

Alfred Rengstl

Rudolf Reitmeier

The present invention provides a process for preparing disproportionation products of dichloromethylsilane in the presence of a catalyst, which comprises contacting dichloromethylsilane with a catalyst consisting of a carrier which is insoluble in the reaction medium and having NR.sub.3 groups or .sup.- X.sup.+ NR.sub.4 groups covalently bonded thereto, in which R represents the same or different alkyl, aryl, or alicyclic groups which may contain heteroatoms as constituents of the ring, or represents a hydrogen radical, and X.sup.- represents a chloride, bromide or iodide.

Process for preparing disproportionation products of

Organopolysiloxanes containing triorganosiloxy terminal units are obtained by a continuous process in which an organopolysiloxane mixture containing organo(poly)siloxanes having triorganosiloxy terminal units and cyclic organopolysiloxanes are introduced into a tube reactor that has been heated to at least 80.degree. C. and which contains a static catalyst bed. The organopolysiloxane composition containing triorganosiloxy terminal units, which exits from the tube reactor is different from the organo(poly)siloxanes containing triorganosiloxy terminal units which were introduced into the reactor. The contents of the reactor in the area between one-third and two-thirds of the distance between the point where the organopolysiloxanes are introduced into the tube reactor and the point where the organopolysiloxanes exit from the reactor, are maintained at a temperature which is at least 50.degree. C. below that which is immediately upstream from the outlet of the reactor.

Continuous process for preparing organopolysiloxanes containing

Linear organopolysiloxanediols are prepared by continuously introducing cyclic organopolysiloxanes, water in an amount of at least 14 mols per gram atom of silicon contained in the cyclic organopolysiloxanes used and water-soluble acid into a recirculating reactor and thereafter separating the aqueous phase from the organopolysiloxanediols more or less immediately after the reaction mixture exits from the recirculating reactor.

Method for preparing linear organopolysiloxanediols

A process for stabilizing organopolysiloxanes containing alkaline compounds such as alkali metal hydroxides, alkali metal silanolates, alkali metal siloxanolates, or a mixture of at least two such compounds, which comprises neutralizing the alkaline compound present in the organopolysiloxanes with a neutralizing agent selected from a compound containing carbon, hydrogen, and oxygen atoms, and optionally at least one halogen atom, in which the compound has 2, 3 or 4 hydrocarbon groups bonded to the same carbon atom via oxygen, or an acylacetic acid ester. The resultant organopolysiloxanes are stabilized against viscosity changes caused by the alkaline compounds.

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Murnau, Germany

Ralph Ottlinger