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:
Nov. 08, 2011
Filed:
Apr. 23, 2009
Evemarie Hamann, Halle, DE;
Hagen Bartossek, Schkopau, DE;
Evemarie Hamann, Halle, DE;
Hagen Bartossek, Schkopau, DE;
Styron Europe GmbH, Horgen, CH;
Abstract
The invention provides a process for polymerizing a polymer comprising monomeric units derived from styrene and 1,3-butadiene, said process comprising: A) adding less than 60 weight percent of the total amount of the butadiene used in the polymerization, to a reactor comprising the total amount of styrene used in the polymerization and solvent; B) adding at least one initiator to the reactor, and allowing the reaction to proceed for a time t; C) adding the remaining amount of butadiene to the reactor in two or more separate additions; and wherein for each butadiene addition, the amount of subsequent butadiene added is less than, or equal to, the amount of butadiene added in the immediately prior addition; and wherein for each butadiene addition, the butadiene is added over a time, t, and after each addition, the reaction is allowed to proceed for a time, t, wherein n is the number of the butadiene addition, and for each addition, n is independently greater than, or equal to, 1.