Patent ID: 7951876

Claim:
A process for preparing a multi-functional polymer comprising the steps of: preparing a multi-functional macroterminator by reacting a short-chain functionalized living polymer with a macroterminator linking agent defined by the formula L b Z(R 4 A) (m−b) where Z is a branch point, R 4 is a covalent bond or a multi-valent organic group, L is a leaving group, A is a leaving group that is less reactive than L, m is an integer equal to the valency of Z, and b is an integer from 2 to m−1, where the short-chain living polymer is characterized by a length that is longer than 0.05 times the entanglement length and shorter than 1.5 times the entanglement length of the short-chain polymer, where the said short-chain living polymer includes a functional group in addition to a living end, and where the functional group derives from synthesizing the short-chain living polymer with an initiator selected from the group consisting of trialkyltin lithium compounds, cyclic amino lithium compounds, and cyclic amino alkyllithium compounds; and terminating a long-chain living polymer with the multi-functional macroterminator, where the long-chain living polymer is characterized by a length that is longer than 1.5 times the entanglement length of the long-chain polymer.