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arXiv · 1204.5665

Self-assembly of spherical interpolyelectrolyte complexes from oppositely charged polymers

Vladimir A. Baulin·Emmanuel Trizac
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Abstract

The formation of inter-polyelectrolyte complexes from the association of oppositely charged polymers in an electrolyte is studied. The charged polymers are linear oppositely charged polyelectrolytes, with possibly a neutral block. This leads to complexes with a charged core, and a more dilute corona of dangling chains, or of loops (flower-like structure). The equilibrium aggregation number of the complexes (number of polycations m+ and polyanions m-) is determined by minimizing the relevant free energy functional, the Coulombic contribution of which is worked out within Poisson-Boltzmann theory. The complexes can be viewed as colloids that are permeable to micro-ionic species, including salt. We find that the complexation process can be highly specific, giving rise to very localized size distribution in composition space (m+,m-).

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Vladimir A. Baulin, Emmanuel Trizac. 2012-04-25. Self-assembly of spherical interpolyelectrolyte complexes from oppositely charged polymers. https://doi.org/10.1039/c2sm25423a

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