Side chain design in brush block copolymer photonic crystals

Brush block copolymers feature polymeric side chains grafted to a linear backbone, and these materials display interesting properties due to their dense functionality, low entanglement, and ability to rapidly assemble to highly ordered nanostructures. Using ruthenium-catalyzed ring-opening metathesis polymn. (ROMP), our group has demonstrated the synthesis and self-assembly of brush block copolymers that behave as photonic crystals. Previous work has shown that the frequency of light reflected can be tuned from the visible to the near-IR regime by varying the backbone length or blending in polymeric additives. However, the impact of side chain phys. properties on self-assembly and photonic behavior remains poorly understood. Herein, we describe a series brush block copolymers featuring side chains with low glass transition temps. The photonic properties and self-assembly of these materials will be discussed