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:
May. 22, 2001
Filed:
Sep. 10, 1998
Jon S. Reed, Baton Rouge, LA (US);
Susan D. Landry, Baton Rouge, LA (US);
Daniel A. De Schryver, Bonheiden, BE;
Billie B. Dadgar, Baton Rouge, LA (US);
Donald E. Balhoff, Baton Rouge, LA (US);
Charles H. Kolich, Baton Rouge, LA (US);
Meng-Sheng Ao, Baton Rouge, LA (US);
Homer C. Lin, Baton Rouge, LA (US);
Albemarle Corporation, Richmond, VA (US);
Abstract
A polyalkylene terephthalate polymer, such as polyethylene terephthalate, polybutylene terephthalate, blends or copolymers thereof, and analogous polyester-type engineering thermoplastics, with which has been blended a flame retardant amount of brominated styrenic polymer, such as brominated polystyrene, that, prior to blending, is characterized by (a) containing less than 700 ppm Cl and having a TGA temperature for 1% weight loss of 340° C. or higher; and/or (b) having an actual M,which is within about 20%, and preferably within about 10%, of its calculated theoretical M,, the theoretical M,being based upon the actual bromine content of the brominated styrenic polymer and the M,of the styrenic polymer reactant used to produce the brominated styrenic polymer; and/or (c) being essentially free of each of the following impurities: (1) ethylene dichloride, (2) bromodichloroethane, (3) dibromochloroethane, (4) dibromodichloroethane, and (5) tribrormochloroethane. These compositions most preferably also further comprise a reinforcing amount of glass fiber and/or a flame retardant synergist dispersed therein. It is now possible to provide polyalkylene terephthalate compositions that have a UL-94 rating of V-O using both {fraction (1/16)}-inch test specimens and {fraction (1/32)}-inch test specimens, and that have superior electrical resistance characteristics as reflected by a higher comparative tracking index and greater melt stability as determined by capillary rheometry.