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:
Aug. 22, 2000
Filed:
May. 26, 1999
Stephen Dennis Janny, Nazareth, PA (US);
Brian Thomas Carvill, Houston, TX (US);
Timothy Wayne Womer, Edinburg, PA (US);
Air Products and Chemicals, Inc., Allentown, PA (US);
Abstract
A method for producing a high solids aqueous solution of poly(vinyl alcohol) in which substantially dry poly(vinyl alcohol) is first fed into a specially designed single screw extruder. Heated water is introduced through a separate entry port downstream of the feed end of the extruder. A temperature of 38 to 121.degree. C. and a back pressure of at least 20,786 kPa are applied to the extruder. The mixture of poly(vinyl alcohol) and water is conveyed through transition and metering sections of the single screw extruder to dispersive and distributive mixing sections to produce a high solids poly(vinyl alcohol) solution which is substantially free of gels. The high solids poly(vinyl alcohol) solution can be used directly in the production of products such as fibers and sheets.