{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,7]],"date-time":"2026-09-07T21:41:28Z","timestamp":1788817288872,"version":"build-2803163510"},"reference-count":31,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2025,7,21]],"date-time":"2025-07-21T00:00:00Z","timestamp":1753056000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Universidad de Guadalajara","award":["PROSNII-2024"],"award-info":[{"award-number":["PROSNII-2024"]}]},{"name":"Universidad de Guadalajara","award":["PROSNII-2025"],"award-info":[{"award-number":["PROSNII-2025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Poly(acrylic acid) (PAA) and hydroxypropylcellulose (HPC) hydrogels were synthesized in the absence of a crosslinker. Chemical crosslinking between PAA and HPC was demonstrated through free radical polymerization by a precipitation reaction in acetone as the solvent. These hydrogels exhibited smaller swelling ratios (1 to 5 g H2O\/g) than homo PAA hydrogels synthesized in water as the solvent. They were swollen in a 0.1 M NaOH solution and subsequently used to remove Ni2+ ions from aqueous solutions with concentrations ranging from 1000 to 4000 ppm. The absorption capacity of these hydrogels ranged from 91 to 340 mg of Ni2+\/g in a rapid 1 h process, and from 122 to 435 mg of Ni2+\/g in a 24 h process, demonstrating an improvement in Ni2+ absorption compared to previously reported hydrogels. The colored 1000 and 2000 ppm Ni2+ solutions became clear after treatment, while the PAA-HPC hydrogels turned green due to the uptake of Ni2+ ions, which were partially chelated by carboxylate groups as nickel polyacrylate and partially precipitated as Ni(OH)2, resulting in an average absorption efficiency of 80%. The hydrogel was able to release the absorbed Ni2+ upon immersion in an HCl solution, with an average release percentage of 76.4%, indicating its potential for reuse. These findings support the use of PAA-HPC hydrogels for cleaning Ni2+-polluted water. The cost of producing 1 g of these hydrogels in laboratory conditions is approximately 0.2 USD.<\/jats:p>","DOI":"10.3390\/gels11070560","type":"journal-article","created":{"date-parts":[[2025,7,21]],"date-time":"2025-07-21T13:59:11Z","timestamp":1753106351000},"page":"560","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Poly(Acrylic Acid)-Based Hydrogel Crosslinked with Hydroxypropylcellulose as a Clarifying Agent in Nickel(II) Solutions"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2667-2158","authenticated-orcid":false,"given":"Rub\u00e9n Octavio","family":"Mu\u00f1oz-Garc\u00eda","sequence":"first","affiliation":[{"name":"Departamento de Qu\u00edmica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas, Universidad de Guadalajara, Boulevard Marcelino Garc\u00eda Barrag\u00e1n 1421, Guadalajara 44430, Jalisco, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cesar Alexis","family":"Ruiz-Casillas","sequence":"additional","affiliation":[{"name":"Licenciatura en Qu\u00edmica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas, Universidad de Guadalajara, Boulevard Marcelino Garc\u00eda Barrag\u00e1n 1421, Guadalajara 44430, Jalisco, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9949-5829","authenticated-orcid":false,"given":"Diego Alberto","family":"Lomel\u00ed-Rosales","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas, Universidad de Guadalajara, Boulevard Marcelino Garc\u00eda Barrag\u00e1n 1421, Guadalajara 44430, Jalisco, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6869-8167","authenticated-orcid":false,"given":"Jorge Alberto","family":"Cort\u00e9s-Ortega","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas, Universidad de Guadalajara, Boulevard Marcelino Garc\u00eda Barrag\u00e1n 1421, Guadalajara 44430, Jalisco, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9535-827X","authenticated-orcid":false,"given":"Juan Carlos","family":"S\u00e1nchez-D\u00edaz","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas, Universidad de Guadalajara, Boulevard Marcelino Garc\u00eda Barrag\u00e1n 1421, Guadalajara 44430, Jalisco, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2295-3059","authenticated-orcid":false,"given":"Luis Emilio","family":"Cruz-Barba","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda Qu\u00edmica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas, Universidad de Guadalajara, Boulevard Marcelino Garc\u00eda Barrag\u00e1n 1421, Guadalajara 44430, Jalisco, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1016\/j.resconrec.2013.01.019","article-title":"Nickel recovery\/removal from industrial wastes: A review","volume":"73","author":"Coman","year":"2013","journal-title":"Resour. 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