{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T07:57:02Z","timestamp":1783411022259,"version":"3.54.6"},"reference-count":21,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2022,8,18]],"date-time":"2022-08-18T00:00:00Z","timestamp":1660780800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Over the years, many materials have been used to restore buildings, paintings, ceramics, and mosaic pieces exhibiting different types of dyes and colour hues. Recently, geopolymers have been used for restoration purposes owing to their high chemical and mechanical resistance. In this work, white metakaolin was used to obtain white geopolymers, cured at 25 and 40 \u00b0C, as bulk materials to be coloured with synthetic organic dyes, i.e., bromothymol blue, cresol red, phenolphthalein, and methyl orange. These dyes were added during the fresh paste preparation to obtain dyed geopolymeric solids. Ionic conductivity and pH measurement confirmed the chemical stability of the consolidated materials, while FT-IR analyses were used to follow the geopolymerisation occurrences at different ageing times (from 7 to 56 days). Finally, the colour hues and properties were assessed in the CIELAB colour space before and after immersion in water.<\/jats:p>","DOI":"10.3390\/polym14163380","type":"journal-article","created":{"date-parts":[[2022,8,18]],"date-time":"2022-08-18T23:28:41Z","timestamp":1660865321000},"page":"3380","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Characterisation of White Metakaolin-Based Geopolymers Doped with Synthetic Organic Dyes"],"prefix":"10.3390","volume":"14","author":[{"given":"Antonio","family":"D\u2019Angelo","sequence":"first","affiliation":[{"name":"Department of Engineering, University of Campania \u201cLuigi Vanvitelli\u201d, Via Roma n. 29, 81031 Aversa, Italy"},{"name":"Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania \u201cLuigi Vanvitelli\u201d, Via Vivaldi 43, 81100 Caserta, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giovanni","family":"Dal Poggetto","sequence":"additional","affiliation":[{"name":"Department of Engineering \u201cEnzo Ferrari\u201d, University of Modena and Reggio Emilia, Via P. Vivarelli 10, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3150-7886","authenticated-orcid":false,"given":"Simona","family":"Piccolella","sequence":"additional","affiliation":[{"name":"Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania \u201cLuigi Vanvitelli\u201d, Via Vivaldi 43, 81100 Caserta, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8524-8715","authenticated-orcid":false,"given":"Cristina","family":"Leonelli","sequence":"additional","affiliation":[{"name":"Department of Engineering \u201cEnzo Ferrari\u201d, University of Modena and Reggio Emilia, Via P. Vivarelli 10, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4448-6984","authenticated-orcid":false,"given":"Michelina","family":"Catauro","sequence":"additional","affiliation":[{"name":"Department of Engineering, University of Campania \u201cLuigi Vanvitelli\u201d, Via Roma n. 29, 81031 Aversa, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"98834","DOI":"10.1039\/C5RA14076E","article-title":"The Maya Blue Nanostructured Material Concept Applied to Colouring Geopolymers","volume":"5","author":"Aranda","year":"2015","journal-title":"RSC Adv."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Dal Poggetto, G., D\u2019Angelo, A., Catauro, M., Barbieri, L., and Leonelli, C. (2022). Recycling of Waste Corundum Abrasive Powder in MK-Based Geopolymers. 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