{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T11:43:50Z","timestamp":1782992630190,"version":"3.54.5"},"reference-count":32,"publisher":"AIP Publishing","issue":"1","funder":[{"DOI":"10.13039\/501100001843","name":"Science and Engineering Research Board","doi-asserted-by":"publisher","award":["SRG\/2023\/000202"],"award-info":[{"award-number":["SRG\/2023\/000202"]}],"id":[{"id":"10.13039\/501100001843","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,7,7]]},"abstract":"<jats:p>Mixtures of weakly and strongly hydrated anions induce non-additive changes in the LCST of thermoresponsive polymers, such as PNIPAM and PEO. Large-scale atomistic simulations of PNIPAM\u2013NaI\u2013Na2SO4 mixtures have shown that these effects arise from the interplay between favorable PNIPAM\u2013iodide interactions and depletion of strongly hydrated sulfate ions. Here, we investigate whether chemically specific polymer\u2013anion interactions are necessary to reproduce such behavior. To this end, we study the coil\u2013globule transition of a generic uncharged linear polymer with non-specific polymer\u2013water and polymer\u2013ion van der Waals interactions in atomistic aqueous solutions of single and mixed salts. Simulations are performed at fixed concentrations of the strongly hydrated salt, Na2SO4, and increasing concentrations of the weakly hydrated salts, NaSCN and NaI. The generic polymer qualitatively reproduces experimentally observed trends in pure NaSCN and Na2SO4 solutions, as well as the non-additive behavior in mixed salt solutions. In particular, the model captures the mutually reinforcing preferential accumulation of weakly hydrated SCN\u2212 ions and the depletion of strongly hydrated SO42\u2212 ions near the polymer that underlies the non-additive behavior. This mutual enhancement correlates with the partitioning of sodium ions from the counterion cloud of SCN\u2212 ions to that of SO42\u2212 ions and is consistent with atomistic simulations of PNIPAM solutions. The model also reproduces the effects of background salt concentration and weakly hydrated anion identity on the non-additive behavior. These results demonstrate that non-specific polymer\u2013ion and polymer\u2013water interactions are sufficient to reproduce non-additive salt effects, suggesting a dominant role of bulk ion\u2013ion and ion\u2013water interactions.<\/jats:p>","DOI":"10.1063\/5.0336301","type":"journal-article","created":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T10:57:04Z","timestamp":1782989824000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":0,"title":["Non-additive ion effects on the coil\u2013globule equilibrium of a generic polymer in aqueous salt solutions"],"prefix":"10.1063","volume":"165","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-2814-0269","authenticated-orcid":false,"given":"Kushagra","family":"Goel","sequence":"first","affiliation":[{"name":"1 Department of Chemistry, Shiv Nadar Institution of Eminence, Greater Noida, Gautam Buddha Nagar, Uttar Pradesh 201314, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8191-0318","authenticated-orcid":false,"given":"Monika","family":"Choudhary","sequence":"additional","affiliation":[{"name":"2 Department of Chemical Engineering, Shiv Nadar Institution of Eminence, Greater Noida, Gautam Buddha Nagar, Uttar Pradesh 201314, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6875-3506","authenticated-orcid":false,"given":"Swaminath","family":"Bharadwaj","sequence":"additional","affiliation":[{"name":"2 Department of Chemical Engineering, Shiv Nadar Institution of Eminence, Greater Noida, Gautam Buddha Nagar, Uttar Pradesh 201314, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2026,7,2]]},"reference":[{"key":"2026070206565635000_c1","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1007\/bf01838161","volume":"25","year":"1888","journal-title":"Arch. 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