Janus Graft Block Copolymers: Design of a Polymer Architecture for Independently Tuned Nanostructures and Polymer Properties

The graft‐through synthesis of Janus graft block copolymers (GBCPs) from branched macromonomers composed of various combinations of homopolymers is presented. Self‐assembly of GBCPs resulted in ordered nanostructures with ultra‐small domain sizes down to 2.8 nm (half‐pitch). The grafted architecture introduces an additional parameter, the backbone length, which enables control over the thermomechanical properties and processability of the GBCPs independently of their self‐assembled nanostructures. The simple synthetic route to GBCPs and the possibility of using a variety of polymer combinations contribute to the universality of this technique. Independently tunable polymer properties: Janus graft block copolymers were synthesized with different backbone length, which serves as a handle for tuning of the thermomechanical properties of the polymer. Simultaneously, the size of the ultra‐small nanodomains is controlled by the side chain length. A broad range of monomers can be used.