Solvent annealing-induced microphase-separation of polystyrene-b-polylactide block copolymer aimed at preparation of ordered nanoparticles/block copolymer hybrid thin film

摘要

A facile way to prepare a Nanoparticles/Block Copolymer (NPs/BCP) hybrid thin film with highly ordered cylindrical nanodomains of vertical orientation is presented in the current work. First, structurally well-defined polystyrene-b-poly(D-lactide) (PS-b-PDLA) and thiol-endfunctionalized PDLA stabilized NPs (PDLA@CdSe) are efficiently synthesized and fully characterized. A neutral surface for PS-b-PDLA is obtained through simple hydrophobic modification on a natural Si (100) wafer. The self-assembled pattern of PS-b-PDLA thin film on the neutral surface is investigated in detail, mainly by Atomic Force Microscope (AFM) under various solvent annealing conditions. The results show that the surface morphology of the thin film is dependent not only on the film thickness, but also on the selectivity of the solvent, vapor pressure and annealing time. A small amount of NPs incorporated into the BCP thin film can promote its microphase separation, resulting in the formation of highly ordered cylindrical nanodomains of vertical orientation in the inorganic NPs/BCP hybrid thin film.