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. 27, 2003
Filed:
Sep. 28, 2001
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
An elastic-thermoplastic graft polymer prepared by a multi-stage free radical polymerization is described. The elastic-thermoplastic graft polymer is prepared by polymerizing (i) one or more monomers containing vinyl groups, and (ii) at least one molecular weight regulating compound, in the presence of (iii) at least one rubber in latex form. The ratio of monomers (M) to the molecular weight regulating compound (MWR) is altered throughout the various stages of the polymerization method. The M:MWR ratio is: from 50:1 to 400:1 in the first stage; from 100:1 to 800:1 in the second stage; and from 200:1 to 2000:1 in the third stage of the polymerization. In at least one further reaction stage of the polymerization, the monomers, in the absence of the molecular weight regulating compound, are polymerized in the presence of the rubber. This further reaction stage occurs before the first stage and/or after the third stage of the polymerization. The multi-stage polymerization is conducted such that: M:MWR (first stage)≦M:MWR (second stage)<M:MWR (third stage). Also described are compositions comprising the elastic-thermoplastic graft polymer, and shaped articles prepared from such compositions.