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. 12, 1997
Filed:
Jun. 08, 1994
Applicant:
Inventor:
Christian Leboeuf, Kingston, CA;
Assignee:
Du Pont Canada Inc., Mississauga, CA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528349 ; 528335 ; 528338 ; 528339 ; 528340 ; 528347 ;
Abstract
A process for the copolymerization of (1) a carboxylic acid comprising terephthalic acid and mixtures thereof with isophthalic acid with (2) a mixture of hexamethylene diamine and 2-methyl pentamethylene diamine. The pressure in the polymerization process is maintained at at least about 2.15 MPa for a period of at least about 40 minutes so that the resultant copolyamide, when annealed, has less than 1% by weight based on the total weight of the copolyamide of fractions having melting points greater than 320.degree. C. Use of lower pressures and times tends to result in formation of a high melting fraction.