{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T23:34:27Z","timestamp":1790638467690,"version":"4.1.0"},"reference-count":16,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,4,25]],"date-time":"2025-04-25T00:00:00Z","timestamp":1745539200000},"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"]}]},{"name":"Guangxi Science and Technology Major Project","award":["AA23062008-2"],"award-info":[{"award-number":["AA23062008-2"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Recent research has focused on developing environmentally friendly flame-retardant coatings to improve the fire resistance of wood. In this study, phytic acid\u2013guanazole (PG), a dual-functional compound synthesized through an ionic reaction between phytic acid and guanazole, was added to KH550-modified urea\u2013formaldehyde resin (KUF) as both a curing agent and flame retardant. The \u2212PO43\u2212 groups from phytic acid act as an acid source to accelerate char formation during combustion, while the \u2212NH2 groups introduced by guanazole release non-combustible gases to dilute oxygen in the air, synergistically enhancing flame retardancy. Additionally, the hygroscopic \u2212PO43\u2212 groups absorb free water in the resin, reducing the curing temperature and accelerating coating solidification. The KH550 coupling agent improves compatibility between KUF and PG while introducing silicon, which forms SiO2 during combustion to strengthen the char layer and further enhance flame resistance. Evaluations showed that PG outperforms conventional tannic acid (TA) in curing efficiency and fire resistance. Comprehensive analyses, including Differential Scanning Calorimetry (DSC), Limiting Oxygen Index (LOI), vertical flame tests, and cone calorimetry, confirmed PG\u2019s dual functionality. Scanning Electron Microscope (SEM) and Raman spectroscopy revealed that PG-modified coatings form denser post-combustion char layers, directly linked to improved fire resistance. As a multifunctional additive, PG eliminates the need for separate curing agents and utilizes bio-based phytic acid, offering cost-effective and sustainable advantages for industrial applications.<\/jats:p>","DOI":"10.3390\/polym17091169","type":"journal-article","created":{"date-parts":[[2025,4,25]],"date-time":"2025-04-25T08:02:57Z","timestamp":1745568177000},"page":"1169","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Dual Flame-Retardant and Curing-Agent Effects of Phytic Acid\u2013Guanazole as an Additive in Fire-Protective Coatings for Wood"],"prefix":"10.3390","volume":"17","author":[{"given":"Xue","family":"Zheng","sequence":"first","affiliation":[{"name":"School of Materials Science and Engineering, Guilin University of Electronic Science and 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":"School of Materials Science and Engineering, Guilin University of Electronic Science and Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cuili","family":"Xiang","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Guilin University of Electronic Science and Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-9510-9155","authenticated-orcid":false,"given":"An","family":"Wei","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Guilin University of Electronic Science and Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuhong","family":"Wei","sequence":"additional","affiliation":[{"name":"Guangxi Zhiguang Office Furniture Co., Ltd., Liuzhou 545006, 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":"School of Materials Science and Engineering, Guilin University of Electronic Science and Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1007\/s00226-022-01415-9","article-title":"A flame-retardant densified wood as robust and fire-safe structural material","volume":"57","author":"Fan","year":"2022","journal-title":"Wood Sci. 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