Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two-Phase Change in Thickness and Viscoelasticity of Polyelectrolyte
  Multilayers Swollen with Ionic Liquid Solution   Polyelectrolyte multilayers (PEM) in combination with good electrolyte
solvents, e.g., ionic liquids (ILs) are potential candidates for the new
generation of electrochemical separators. Swelling PEM with aqueous IL
solutions is one way to incorporate IL in PEM. In addition to quantifying the
IL uptake in PEM, physical characterization of the swollen PEM is essential for
their potential applications and to uncover the underlying molecular process of
the swelling. In this article, thickness and viscoelasticity of
PEI(PSS/PADMAC)4PSS and PEI(PSS/PAH)4PSS multilayers were determined upon
uptake of aqueous solutions of 1-Ethyl-3methylimidazolium chloride, a
water-soluble IL. This was done by employing the Kelvin-Voigt model in
combination with the frequency and dissipation shifts measured using quartz
crystal microbalance with dissipation technique. The modeled thickness and
viscoelasticity of the multilayers change in two phases with increasing IL
concentration. In the first phase, a small increase in PEM thickness
accompanies a two to three-fold increase in PEM viscoelasticity, whereas the
changes are other ways around in the second phase. Two phenomenon contributes
to the two-phase changes: 1) the exchange between hydrated ions of IL and
in-situ water of PEM influencing the overall ion and water content in PEM and
2) the hydrophobic and electrostatic interactions between incorporated IL and
PEM influencing the structural integrity of PEM.

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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
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The categories of this paper are: acc-phys
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The categories of this paper are: plasm-ph
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The categories of this paper are: math-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-th
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The categories of this paper are: supr-con
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The categories of this paper are: hep-ph
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The categories of this paper are: econ
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The categories of this paper are: gr-qc
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The categories of this paper are: ao-sci
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The categories of this paper are: cs
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The categories of this paper are: nucl-ex