Synthesis and self-assembly of brush block copolymers with various grafting densities

Brush block copolymers are of intensive interest due to their abilities to undergo rapid self-assembly, leading to potential applications in the field of nanoscience. The relatively low kinetic barrier to reach an ordered equil. structure can be, in part, attributed to the reduced chain entanglement engendered by the densely grafted polymeric side-chains. To better understand the effects of side-chains on the self-assembly and phys. properties, we have prepd. a series of di-block copolymers with various side-chain densities. These copolymers, synthesized by ring-opening metathesis polymn. (ROPM), are designed so that the sidechains are evenly spaced out across the entire backbone. The self-assembly of these copolymers have been investigated by SEM, TEM, and SAXS