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:
Oct. 17, 2000
Filed:
Apr. 24, 1998
Jon S Reed, Baton Rouge, LA (US);
Charles H Kolich, Baton Rouge, LA (US);
Billie B Dadgar, Baton Rouge, LA (US);
Donald E Balhoff, Baton Rouge, LA (US);
Meng-Sheng Ao, Baton Rouge, LA (US);
Homer C Lin, Baton Rouge, LA (US);
Thorsten W Brockmann, Columbia, SC (US);
David R Brackenridge, Baton Rouge, LA (US);
Albelmarle Corporation, Richmond, VA (US);
Abstract
This invention relates to a thermally stable brominated polystyrene composition which contains alkali metal base (e.g., NaOH) in an amount less than about 1 wt % such that if the flame retardant is dissolved in bromochloromethane and the resultant solution is extracted with water, the resultant water extract exhibits a pH of at least about 9.0. A preferred composition of this type even when heated to 315.degree. C. for one hour did not undergo darkening--the color remained tan. Comparative samples not containing the base turned black under these same conditions. Especially useful compositions additionally have less than 500 ppm, and better still, less than 100 ppm total Cl, and at least about 67 wt % bromine. Processes for producing the compositions are also described.