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Chain Diffusion in Lamellar Block Copolymers

Michael Murat·Gary S. Grest·Kurt Kremer
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Abstract

Diffusion of symmetric diblock copolymer chains in macroscopically oriented lamellar block copolymers are studied in a molecular dynamics simulation. Results for diffusion constant both parallel $D_\parallel$ and perpendicular $D_\perp$ to the lamellar planes are compared to results in the disordered one phase region. For diblocks of length N=40 (1.1 N_e) and $100 (3N_e)$, where $N_e$ is the entanglement length of a homopolymer melt at the same density, $D_\parallel$ is nearly independent of $χ$, while $D_\perp$ is strongly suppressed as $χ$ is increased. These results are in agreement with theoretical predictions based on the Rouse model. The isotropic diffusion constant of quenched disordered systems is approximated fairly well by $(2D_\parallel+D_\perp)/3$ of the corresponding lamellar system.

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Michael Murat, Gary S. Grest, Kurt Kremer. 1997-05-28. Chain Diffusion in Lamellar Block Copolymers. https://arxiv.org/abs/cond-mat/9705293

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