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:
Dec. 29, 1992
Filed:
Dec. 27, 1990
Sibbley P Gauntt, Richmond, VA (US);
Hua-Feng Huang, Chadds Ford, PA (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A process is disclosed for heating never-dried para-aramid fibers containing 20 to 200 wt % water, based on dry polymer weight to form a fiber having a modulus of greater than 800 gpd while retaining a high tenacity. The fibers are heated in one or more microwave resonant cavity applicators to a temperature of 250.degree. C. to 425.degree. C. and preferably 270.degree. C. to 310.degree. C. while under a tension of 0.2 to 10 grams per denier. The preferred para-aramid is poly(p-phenylene terephthalamide). Fibers having a density of less than 1.43 g/cc can be made; and fibers having moduli greater than 1100 gpd can be made.