The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 24, 1980
Filed:
Dec. 28, 1978
Werner Graf, Burghausen, DE;
Volker Frey, Burghausen, DE;
Peter John, Burghausen, DE;
Norbert Zeller, Burghausen, DE;
Wacker-Chemie GmbH, Munich, DE;
Abstract
This invention relates to an improved process for preparing polysiloxanes having hydrocarbon radicals bonded to silicon atoms via oxygen, by reacting a halosilane with an alcohol and water in the presence of the desired polysiloxane, the improvement which comprises continuously introducing into a reactor equipped with a column and possibly a reflux condenser and the desired polysiloxane, an alcohol, water and, if necessary, an acid catalyst which promotes the condensation of Si-bonded condensable groups, in an amount such that the reactor contains at least 5 percent by weight of alcohol and 0.001 to 5 percent by weight of catalyst, based on the weight of the alcohol, catalyst and polysiloxane present in the reactor in which the contents of the reactor are heated to the reflux temperature and the halosilane is introduced into the column at least one meter above the bottom of the column while continuously removing the polysiloxane from the reactor at the same rate as it is formed.