Liquid crystalline orientation of semiconducting nanorods in a semiconducting matrix

This paper describes the synthesis of narrowly distributed block copolymers consisting of a hole conducting triarylamine block and an anchor block via RAFT polymerization. The anchor block is thereby introduced via a reactive ester approach. Block copolymers with dopamine anchor groups bind to oxidic semiconductors like TiO2, SnO2, and ZnO. Thus, it becomes possible to cover inorganic electron conducting (acceptor) nanomaterials with a Corona of an organic hole conducting (donor) polymer like poly(triphenylamine), giving new hybrid materials. The poly(triphenylamine) grafted to inorganic nanorods allows the preparation of stable nanorod dispersions in appropriate solvents. At higher concentration the nanorods form liquid crystalline phases in various solvents and in a low T-g oligotriphenylamine matrix. This offers the potential to orient semiconducting inorganic nanorods in a hole conducting polymer matrix by self-assembly.