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arXiv · 1805.08508

5D Entanglement in Star Polymer Dynamics

Airidas Korolkovas
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Abstract

Star polymers are within the most topologically entangled macromolecules. For a star to move the current theory is that one arm must retract to the branch point. The probability of this event falls exponentially with molecular weight, and a quicker relaxation pathway eventually takes over. With a simulation over a hundred times faster than earlier studies, we demonstrate that the mean square displacement scales with a power law 1/16 in time, instead of the previously assumed zero. It suggests that star polymer motion is the result of two linear relaxations coinciding in time. By analogy to linear polymers, which reptate with a random walk embedded in a 3D network, we show that star polymers relax by a random walk in a 5D network.

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Airidas Korolkovas. 2018-05-22. 5D Entanglement in Star Polymer Dynamics. https://doi.org/10.1002/adts.201800078

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