Patent ID: 8492479

Claim:
A process for preparing a diene block copolymer, of which at least one of said blocks is constituted of a diene elastomer and at least the other of said blocks is constituted of a polyether, wherein the process comprises a step of reacting a living diene elastomer with a functionalizing agent having a functional polyether block of number-average molecular weight from 150 to 5000 g/mol, represented by general formula I: R 1 A) m Formula I in which: R 1 represents a C 1 -C 15 alkyl, C 6 -C 15 aryl or C 7 -C 15 aralkyl hydrocarbon-based derivative of valency m; m is an integer from 1 to 4; and A represents, identically or differently when m is greater than 1, the group of general formula II in which: R 2 represents a C 1 -C 10 alkylene radical; R 3 represents a divalent hydrocarbon derivative from C 1 -C 50 alkyl, C 6 -C 50 aryl or C 7 -C 50 aralkyl hydrocarbon-based derivative; R 4 represents a C 1 -C 50 alkyl, C 6 -C 50 aryl or C 7 -C 50 aralkyl radical; X represents, identically or differently when i is equal to 0 or 1, a group chosen from a halogen atom and a group of formula —OR 5 in which R 5 represents a C 1 -C 18 alkyl, C 5 -C 18 cycloalkoxyl or C 6 -C 18 aryl radical; n is a number greater than 1, so that the polyether block has a number-average molecular weight from 150 to 5000 g/mol; and i is an integer from 0 to 2.