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. 22, 1994
Filed:
Jan. 29, 1993
George E Rotter, Clarendon Hills, IL (US);
John L Melquist, Naperville, IL (US);
Weilong Chiang, Naperville, IL (US);
Boh C Tsai, Inverness, IL (US);
John J Kelly, Warrenville, IL (US);
Amoco Corporation, Chicago, IL (US);
Abstract
Disclosed is a process for obtaining polyester articles, including foamed articles, containing low levels of extractable branching agent. The process comprises: (1) forming a molten mixture comprising (i) a major amount of a first resin composition comprising polyester and from 0 up to about 1 wt. % of a compound capable of branching the polyester, and (ii) a minor amount of a second polyester resin composition comprising at least about 50 wt. % polyester resin and greater than about 2 wt. % of a compound capable of branching the polyester, wherein the relative amounts of (i) and (ii) are such that said molten mixture comprises from about 0.1 wt. % to about 1 wt. % of said branching compound; (2) adding a blowing agent to the molten mixture; and (3) extruding the resultant mixture to obtain a foam. The invention is also directed to the second composition used in the above process, and foamed polyester articles obtained from the process.