Fabrication process for copolymers of controlled architecture via the use of functional radical initiators in a living radical polymerisation, and initiator compositions and corresponding copolymers

摘要

Method for preparation of sequence polymer comprises (1) radical polymerisation of monomer with the help of an initiator; (2) polymerizing polymer with a second monomer to produce an active copolymer which is then used as initiator for polymerisation of at least a third monomer. Method for preparation of a sequence polymer comprises the radical thermal polymerisation of at least one monomer, M1 with the help of an initiator of formula X-A-Y (I); X and Y = reactive monovalent functional group which can be reactivated in active radical polymerisation, and A = divalent group containing a bond capable of self-division to generate free radicals X-D and E-Y, to obtain a polymer of formula X-D-(or Y-E)PM1-T (II); T = terminal group X-D or Y-E formed by recombination and/or a terminal group with an unsaturated linkage and a saturated linkage which forms terminal groups by dismutation; and a second step in which (II) is subjected to active polymerisation, leading to insertion between X and D (or Y and E) of a sequence polymer PM2, the active copolymer thus produced being used as an initiator for a new step involving the active radical polymerisation of at least one monomer M3. The method is subject to the condition that PM2 does not represent a sequence polystyrene or a styrene-acrylonitrile copolymer when PM1 is methacrylic or dienic polymer or polyisoprene, in the case of bi- or tri-sequence polymers, polymers obtained using azoic, disulfide or peroxide initiator, or when X and Y represent groups producing nitroxide or 2,2,6,6-tetramethyl-1-piperidinyloxy radicals. An Independent claim is also included for a free radical initiator of formula X-L1-A'-L2-Y; A' = selected from e.g. -N=N-, and -O-O-C(O)-; L1 and L2 = represent divalent groups and X and Y are as previously described.