Polyacrylate-based graft copolymer

A process for the preparation of a polyacrylate-based graft copolymer comprising a polyacrylate backbone and polyolefin side chains grafted thereon, wherein the graft copolymer is prepared by reacting a first polymer and a second polymer, wherein

• the first polymer comprises recurring units having the structure (I) and optionally further recurring units having the structures (II):
• wherein
• R1, R3 is H or CH3 and
• R2 is a hydrocarbon moiety comprising 1 to 6 carbon atoms,
• one of R4 and R5 is H and the other one of R5 and R4 is COOR2, C≡N, Cl, or an aliphatic or aromatic hydrocarbon moiety optionally containing one or multiple hetero atom functionalities, wherein R2 in (I) is different from R2 in (II), and
• the second polymer is a functionalized polyolefin having one or multiple hydroxyl functional groups,
• wherein the graft copolymer is formed by transesterification of the COOR2 group of (I) or (II) with the hydroxyl functional group of the functionalized polyolefin,
• the process comprising the step of reacting the first polymer with the second polymer by means of transesterification.