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. 11, 2003
Filed:
Oct. 04, 2001
James C. Gill, Macedonia, OH (US);
James L. Dever, Medina, OH (US);
Albemarle Corporation, Richmond, VA (US);
Abstract
A brominated polystyrene product made by the process comprising pretreating a solution of a polystyrene reactant comprising from about five to about 20 percent by weight of the polystyrene reactant, in a halogenated hydrocarbon solvent with at least about 0.1 percent by weight of an additive to suppress halogenation of the polystyrene backbone, prior to brominating the polystyrene in the presence of a catalyst; subsequently adding a metal halide bromination catalyst to the solution, capable of effecting bromination of the ring without causing crosslinking of the polystyrene; adding to the solution from about 1 to about 3.4 moles of a brominating agent, per mole of polystyrene repeating units; reacting the polystyrene with the brominating agent at a temperature of from about −20° C. to about 50° C., and isolating the brominated polystyrene. A brominated polystyrene is provided having a backbone halogen content of less than about 750 ppm and a &Dgr;E color of from about 5 go about 19.