Chain elongation suppression of cyclic block copolymers in lamellar microphase-separated bulk.

The Journal of chemical physics

PubMedID: 15260649

Matsushita Y, Iwata H, Asari T, Uchida T, ten Brinke G, Takano A. Chain elongation suppression of cyclic block copolymers in lamellar microphase-separated bulk. J Chem Phys. 2004;121(2):1129-32.
Chain elongation suppression of cyclic block copolymers in microphase-separated bulk was determined quantitatively. Solvent-cast and annealed films are confirmed to show alternating lamellar structure and their microdomain spacing D increases with increasing total molecular weight M according to the relationship D proportional, variant M0.59, which agrees quite consistently with the theoretically predicted power law, i.e., D proportional, variant M3/5. This result is in contrast to the well-established issue for linear block copolymers, where the relationship D proportional, variant M2/3 has been confirmed to hold both experimentally and theoretically. This means that chain elongation of each component block is suppressed considerably, owing to their looped conformation in strongly segregated bulk.