{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T03:43:30Z","timestamp":1791171810134,"version":"4.1.0"},"reference-count":52,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,5,31]],"date-time":"2024-05-31T00:00:00Z","timestamp":1717113600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guangxi Science and Technology Major Project","award":["AA23062008-1"],"award-info":[{"award-number":["AA23062008-1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>To broaden the applications of wood, it is necessary to prepare flame-retardant coatings that can protect wood substrates during combustion. In this study, a bio-based, intumescent, flame-retardant phytic acid\u2013melamine polyelectrolyte (PM) was prepared using phosphorus-rich biomass phytic acid and nitrogen-rich melamine as raw materials through an ion crosslinking reaction. Subsequently, a series of bio-based, flame-retardant wood coatings were prepared by optimizing the structure of urea\u2013formaldehyde resin with the addition of melamine, sodium lignosulfonate, and PM as a flame-retardant curing agent. Woods coated with PM-containing coatings displayed significantly improved flame-retardant performances in comparison to uncoated woods. For PM-cured woods, the measured values of total heat release and total smoke production were 91.51% and 57.80% lower, respectively, compared with those of uncoated wood. Furthermore, the fire growth index decreased by 97.32%, indicating a lower fire hazard. This increase in flame retardancy and smoke suppression performance is due to the dense expanded carbon layer formed during the combustion of the coating, which isolates oxygen and heat. In addition, the mechanical properties of the flame-retardant coatings cured with PM are similar to those cured with a commercial curing agent, NH4Cl. In addition, the prepared flame-retardant coating can also stain the wood. This study proves the excellent flame-retarding and curing effect of ammonium phytate in urea\u2013formaldehyde resin coatings and provides a new approach for the application of bio-based flame retardants in wood coatings.<\/jats:p>","DOI":"10.3390\/polym16111557","type":"journal-article","created":{"date-parts":[[2024,5,31]],"date-time":"2024-05-31T06:35:32Z","timestamp":1717137332000},"page":"1557","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Preparation of a Flame-Retardant Curing Agent Based on Phytic Acid\u2013Melamine Ion Crosslinking and Its Application in Wood Coatings"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-9510-9155","authenticated-orcid":false,"given":"An","family":"Wei","sequence":"first","affiliation":[{"name":"College of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shunxiang","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9012-2639","authenticated-orcid":false,"given":"Yongjin","family":"Zou","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China"},{"name":"Nanning Guidian Electronic Technology Research Institute Co., Ltd., Nanning 530000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cuili","family":"Xiang","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2900-1325","authenticated-orcid":false,"given":"Fen","family":"Xu","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4684-683X","authenticated-orcid":false,"given":"Lixian","family":"Sun","sequence":"additional","affiliation":[{"name":"College of Materials Science and Engineering, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9993","DOI":"10.1021\/acsnano.9b00089","article-title":"Clear Wood toward High-Performance Building Materials","volume":"13","author":"Jia","year":"2019","journal-title":"ACS Nano"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"224","DOI":"10.1038\/nature25476","article-title":"Processing bulk natural wood into a high-performance structural material","volume":"554","author":"Song","year":"2018","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1821","DOI":"10.1007\/s42114-022-00440-3","article-title":"Highly fire-retardant optical wood enabled by transparent fireproof coatings","volume":"5","author":"Chu","year":"2022","journal-title":"Adv. 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