Chemistry Colloquium: Dr. Javid Rzayev

The Department of Chemistry in the College of Arts and Sciences is pleased to welcome Dr. Javid Rzayev, Professor and Chair, Department of Chemistry at University at Buffalo.

Title: Nanostructured materials from bottlebrush copolymers

Abstract:

Bottlebrush copolymers are comb-like macromolecules with densely grafted side chains that offer an increased persistence length, cylindrical shape, and low density of entanglements as compared to linear polymers. Materials with nanostructured domains are typically prepared from bottlebrush copolymers with at least two different types of side chains that are distributed along the backbone in a statistical, Janus, core-shell or blocky arrangement. In the first part of this talk, we will present the synthesis and phase behavior of a new type of bottlebrush architecture with a compositional gradient along the backbone. Gradient bottlebrush copolymers were prepared by one-shot copolymerization of endo- and exo-norbornene functionalized macromonomers. Phase behavior of gradient polystyrene-polylactide bottlebrush copolymers was shown to differ significantly from their block bottlebrush analogs as evidenced by the presence of a large cylindrical morphology window, the observation of the elusive bicontinuous gyroid morphology, and consistently smaller domain spacings when compared to bottlebrush block analogs with identical molecular dimensions and compositions. In the second part of this talk, we will describe the fabrication of robust, covalently connected percolating bottlebrush networks from end-reactive and peripherally-reactive bottlebrush copolymers that allow for the replication of molecular dimensions of the bottlebrush copolymer building blocks and the preparation of nanoporous materials with BJH pore sizes as low as 4 nm.