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. 15, 1982
Filed:
Mar. 03, 1981
John W Collette, Wilmington, DE (US);
Charles W Tullock, Landenburg, PA (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
A fractionable elastic polypropylene which has an inherent viscosity of 1.5-9, exhibits no yield point, has a tensile set not exceeding 150% and contains about 10 to 80% by weight of a diethyl ether-soluble fraction having an inherent viscosity exceeding 1.50. This polypropylene is a direct reaction product and thus need not be separated into its component parts to be a useful elastomer. Also described is the diethyl ether-soluble polypropylene fraction of the direct reaction product which has about 0.5% to about 5% isotactic crystallinity and exhibits birefringence when a film formed from said fraction is viewed under crossed Nicol prisms in a polarizing microscope at about 25.degree. C. or is stretched between crossed polarizing sheets at about 25.degree. C. The diethyl ether-soluble fraction itself is a useful elastomeric material.