{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T22:18:17Z","timestamp":1788387497960,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,9,15]],"date-time":"2021-09-15T00:00:00Z","timestamp":1631664000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"Engineering and Physical Sciences Research Council","doi-asserted-by":"publisher","award":["EP\/R512205\/1"],"award-info":[{"award-number":["EP\/R512205\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Gels"],"abstract":"<jats:p>Resorcinol\u2013formaldehyde (RF) gels are porous materials synthesized via a sol\u2013gel reaction and subsequently dried, producing structures with high surface areas and low densities\u2014properties that are highly attractive for use in various applications. The RF gel reaction takes place in the presence of a catalyst, either acidic or basic in nature, the concentration of which significantly impacts final gel properties. The full extent of the catalyst\u2019s role, however, has been subject to debate, with the general consensus within the field being that it is simply a pH-adjuster. The work presented here explores this theory, in addition to other theories postulated in the literature, through the synthesis and analysis of RF gels catalysed by mixtures of relevant compounds with varying concentrations. The relationship between catalyst concentration and initial solution pH is decoupled, and the individual roles of both the cation and the anion within the catalyst are investigated. The results presented here point towards the significance of the metal cation within the RF gel reaction, with similar structural properties observed for gels synthesized at constant Na+ concentrations, regardless of the initial solution pH. Furthermore, through the use of alternative cations and anions within catalyst compounds, the potential effects of ions on the stabilization of macromolecules in solution are explored, the results of which suggest a \u2018Hofmeister-like\u2019 series could be applicable within the catalysis of RF gel reactions.<\/jats:p>","DOI":"10.3390\/gels7030142","type":"journal-article","created":{"date-parts":[[2021,9,15]],"date-time":"2021-09-15T21:47:11Z","timestamp":1631742431000},"page":"142","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Investigating the Role of the Catalyst within Resorcinol\u2013Formaldehyde Gel Synthesis"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4142-2093","authenticated-orcid":false,"given":"Elisha","family":"Martin","sequence":"first","affiliation":[{"name":"Department of Chemical and Process Engineering, University of Strathclyde, Glasgow G1 1XJ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5326-2408","authenticated-orcid":false,"given":"Martin","family":"Prostredny","sequence":"additional","affiliation":[{"name":"Department of Chemical and Process Engineering, University of Strathclyde, Glasgow G1 1XJ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3915-8887","authenticated-orcid":false,"given":"Ashleigh","family":"Fletcher","sequence":"additional","affiliation":[{"name":"Department of Chemical and Process Engineering, University of Strathclyde, Glasgow G1 1XJ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1002\/adma.200390020","article-title":"Preparation and Properties of Resorcinol\u2013Formaldehyde Organic and Carbon Gels","volume":"15","author":"Ritter","year":"2003","journal-title":"Adv. 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