Synthesis of polyethylene-polyacrylate block copolymers in continuous flow

Continuous flow reactions for the synthesis of block copolymers are a useful synthetic strategy because they provide better control over the polymerization reactions with easy scaling-up ability. Herein, a continuous flow system has been designed to combine two adverse polymerization processes, coordination-insertion using gaseous ethylene and free radical polymerization utilizing monomers of the acrylate family, to form polar polyethylene block copolymers. We demonstrate that a gas-liquid heterogeneous droplet flow system can lead to a successful living ethylene polymerization in which the gaseous component contains the reactive monomer. The addition of acrylates switches the reaction location to the liquid phase through the formation of a macroinitiator for the radical pathway and retarding the ethylene polymerization. We demonstrate that block copolymer segments can engage all phases of the droplet flow system and enable the synthesis of polar polyolefin block copolymers employing a single catalyst.