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, 2005
Filed:
Apr. 05, 2001
Gian Tommaso Viola, Cervia-Ravenna, IT;
Luca Soddu, San Pietro Terme Bologna, IT;
Sabrina Isidori, Ravenna, IT;
Attilio Taccioli, Milanese-Milan, IT;
Francesco Masi, Lodigiano-Lodi, IT;
Gian Tommaso Viola, Cervia-Ravenna, IT;
Luca Soddu, San Pietro Terme Bologna, IT;
Sabrina Isidori, Ravenna, IT;
Attilio Taccioli, Milanese-Milan, IT;
Francesco Masi, Lodigiano-Lodi, IT;
Polimeri Europa S.p.A., Brindisi, IT;
Abstract
Process for the production of statistic elastomeric conjugated diene-vinyl arene copolymers having a branched structure which comprises: (1) anionic copolymerization in solution of the conjugated diene and vinyl arene monomers, in the presence of randomizing agents and an initiator selected from the group of Lithium alkyls, the copolymerization being carried out until the almost total disappearance of the monomers; (2) addition to the solution of step (1) of a quantity of Lithium alkyl from 1 to 4 times the molar quantity of the Lithium alkyl of step (1); (3) addition to the polymeric solution of step (2) of a compound having the general formula R—Br, the molar ratio between R—Br and the total Lithium alkyl ranging from 0.6/1 to 1/1, preferably from 0.7/1 to 0.9/1, thus obtaining an elastomeric branched copolymer.