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:
Feb. 20, 1979
Filed:
Jan. 12, 1978
Robert M Lafferty, Graz, AT;
Elmar Heinzle, Graz, AT;
Agroferm A.G., Chur, CH;
Abstract
The use of cyclic carbonic acid esters of the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be the same or different, are hydrogen or alkyl with 1 to 6 C-atoms, as a solvent for racemic or optically active poly-(.beta.-hydroxybutyric acid). The preferred embodiment uses hot (120 to 150.degree. C) ethylene carbonate or 1,2-propylene carbonate to extract poly-(.beta.-hydroxybutyric acid) from moist or dry fermentation masses. These solvents have the advantage that the extracted poly-(.beta.-hydroxybutyric acid) is precipitated in good yield from them on cooling. In addition they may be recycled without the need for a solvent regeneration step. These cyclic carbonic acid esters may also be used as the solvent in the processing of poly-(.beta.-hydroxybutyric acid) by e.g. wet spinning.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile