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:
Jul. 24, 1990
Filed:
Jul. 29, 1988
James E McGrath, Blacksburg, VA (US);
Youngtai Yoo, Blacksburg, VA (US);
Robert B Turner, Lake Jackson, TX (US);
Diane M Lewis, Lake Jackson, TX (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
Polyether active hydrogen compounds having at least two terminal active hydrogen groups on primary carbon atoms are prepared by (a) forming polyoxyalkylene molecules each having at least one active hydrogen precursor, (b) linking at least two of the polyoxyalkylene molecules, and (c) converting the active hydrogen precursor groups to active hydrogen groups on primary carbon atoms. The polyoxyalkylene molecule is formed by exposing a reaction mixture comprising at least one alkylene oxide and at least one protective initiator to conditions effective for the polymerization of the alkylene oxides. Linking is accomplished at polyether chain ends distal to the protected active hydrogen precursor groups, such that the active hydrogen precursors remain on the linked polyether chains until they are converted to active hydrogen groups. The process is particularly useful to produce polyether compounds having at least about 80 mole percent primary active hydrogen groups, which compounds are useful, for instance, in forming polyurethanes.