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DOE OSTI · 1574901

Controlling Complex Coacervation via Random Polyelectrolyte Sequences

Rumyantsev, Artem M.·Jackson, Nicholas E.·Yu, Boyuan·Ting, Jeffrey M.·Chen, Wei·Tirrell, Matthew V.·de Pablo, Juan J.
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Abstract

The utilization of chemical sequence control in polymeric materials is key to enabling material design on par with biomacromolecular systems. One important avenue for scalable sequence-controlled polymers leverages the random copolymerization of distinct monomers, with the statistical distribution of the monomeric sequence arising from reaction kinetics following a first-order Markov process. Here we utilize the framework of the random phase approximation (RPA) to develop a theory for the phase behavior of symmetric polyelectrolyte coacervates whose chemical sequences are dictated by simple statistical distributions. We find that a high charge "blockiness" within the random sequences favors the formation of denser and more salt-resistant coacervates while simultaneously increasing the width of the two-phase region. Here, we trace these physical effects to the increased cooperativity of Coulomb interactions that results from increased charge blockiness in oppositely charged polyelectrolytes.

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Rumyantsev, Artem M., Jackson, Nicholas E., Yu, Boyuan, Ting, Jeffrey M., Chen, Wei, Tirrell, Matthew V., de Pablo, Juan J.. 2019-09-23. Controlling Complex Coacervation via Random Polyelectrolyte Sequences. https://doi.org/10.1021/acsmacrolett.9b00494

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