Editing Polyelectrolyte (section)

{{Short description|Polymers whose repeating units bear an electrolyte group}}
[[File:polyelectrolyte examples.png|thumb|200px|Chemical structures of two synthetic polyelectrolytes, as examples. To the left is [[sodium polystyrene sulfonate|poly(sodium styrene sulfonate)]] (PSS), and to the right is [[polyacrylic acid]] (PAA). Both are negatively charged polyelectrolytes when dissociated. PSS is a 'strong' polyelectrolyte (fully charged in solution), whereas PAA is 'weak' (partially charged).]]

'''Polyelectrolytes''' are [[polymers]] whose repeating units bear an [[electrolyte]] group. [[Ion#Anions and cations|Polycations and polyanions]] are polyelectrolytes. These groups [[dissociation (chemistry)|dissociate]] in [[aqueous]] solutions (water), making the polymers [[charge (physics)|charged]]. Polyelectrolyte properties are thus similar to both electrolytes ([[salts]]) and polymers (high [[molecular weight]] compounds) and are sometimes called '''polysalts'''. Like salts, their solutions are electrically conductive. Like polymers, their solutions are often [[viscosity|viscous]]. Charged molecular chains, commonly present in soft matter systems, play a fundamental role in determining structure, stability and the interactions of various molecular assemblies. Theoretical approaches<ref name="Gennes1979">{{cite book|first=Pierre-Gilles |last=de Gennes|title=Scaling Concepts in Polymer Physics|url={{google books |plainurl=y |id=ApzfJ2LYwGUC}}|year=1979|publisher=Cornell University Press|isbn=0-8014-1203-X}}</ref><ref>{{cite journal | last1=Chremos | first1=A. | last2=Horkay | first2=F. | title=Disappearance of the polyelectrolyte peak in salt-free solutions | journal=Phys. Rev. E | publisher=American Physical Society (APS) | volume=102 | date=2020-07-27 | issue=1 | doi=10.1103/PhysRevE.102.012611 | pages=012611| pmid=32794995 | pmc=8243406 | bibcode=2020PhRvE.102a2611C }}</ref> to describe their statistical properties differ profoundly from those of their electrically neutral counterparts, while technological and industrial fields exploit their unique properties. Many biological molecules are polyelectrolytes. For instance, [[polypeptides]], [[glycosaminoglycan]]s, and [[DNA]] are polyelectrolytes. Both natural and synthetic polyelectrolytes are used in a variety of industries.
 {{Quote box|width = 35%
 |title = [[International Union of Pure and Applied Chemistry|IUPAC]] definition
 |quote = '''polyelectrolyte''': Polymer composed of macromolecules in which a substantial portion of the constitutional units contains ionic or ionizable groups, or both. (See Gold Book entry for note.)
<ref name='Gold Book "polyelectrolyte"'>{{cite journal |title=polyelectrolyte |url=https://goldbook.iupac.org/terms/view/P04728 |website=Gold Book |date=2014 |publisher=IUPAC |access-date=1 April 2024 |ref=Gold Book P04728 |doi=10.1351/goldbook.P04728|url-access=subscription }}</ref>
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