Tailoring Co-assembly of Nanodiscs and Block Copolymer-Based Supramolecules by Manipulating Interparticle Interactions

Anisotropic nanoparticles exhibit interesting properties and their controlled assemblies are highly desirable to generate functional materials. Different from their spherical counterparts, the incorporation of anisotropic nanoparticles in nanostructured polymeric matrices such as block copolymer or supramolecules depends not only on the particle/polymer interactions and relative size ratio between the particle and polymer features but also on the interparticle interactions. Here, we fill this knowledge gap by systematically studying the block copolymer-based supramolecular nanocomposite containing anisotropic copper sulfide nanodiscs, and evaluate the effect of competition between the ligand–polymer interaction and internanodisc interaction on the arrangement and interparticle spacing of nanodiscs once blended with supramolecules. The interdisc interaction was modulated by varying the ligand density and/or the ligand shell thickness on the surface of nanodiscs. Reduction in the interdisc interaction leads to isolated dispersion of nanodiscs in supramolecules. On the other hand, increasing the interdisc interaction results in simultaneous self-assembly of nanodiscs into "soft-rod" nanoparticles and co-assembly of nanodiscs with supramolecules. The length of the "soft-rod" nanoparticle and the interparticle spacing also shows a strong dependence on the interdisc interaction and can be tailored by adding free small molecules in the supramolecular matrix. These systematic studies provide valuable insights toward relative strength of various interactions that can be readily applied to achieve morphological control in anisotropic particle-containing nanocomposites.