Patent ID: 7750087

Claim:
A functionalized polymer prepared by a process comprising the steps of: preparing a pseudo-living polymer by polymerizing conjugated monomer with a lanthanide-based catalyst, where said pseudo-living polymer is characterized by having greater than about 85 percent of the polymer in the 1,4-cis microstructure and less than about 3 percent of the polymer is in the 1,2- or 3,4-microstructure; and reacting the pseudo-living polymer with a functionalizing agent defined by the formula (I) where A is a substituent that will undergo an addition reaction with a pseudo-living polymer, R 1 is a divalent organic group, R 2 is a monovalent organic group, and each R 4 , which may be the same or different, is a monovalent organic group or a substituent defined by —OR 5 where R 5 is a monovalent organic group, with the proviso that A, R 1 , R 2 , R 4 , and R 5 are substituents that will not protonate a pseudo-living polymer.