{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T09:06:04Z","timestamp":1790067964898,"version":"4.0.1"},"reference-count":36,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T00:00:00Z","timestamp":1790035200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guangxi Science and Technology Major Program","award":["AA 23062009"],"award-info":[{"award-number":["AA 23062009"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>To overcome the flammability and formaldehyde-emission problems associated with plywood, a novel soy protein-based intumescent flame-retardant adhesive with phosphorus\u2013nitrogen\u2013silicon (P-N-Si) synergism (C@Si@APP) was developed in this study. C@Si@APP was initially prepared by coating silane-modified ammonium polyphosphate with collagen. Subsequently, C@Si@APP was combined with lignin and adenine and incorporated into a soy protein, collagen, and isocyanate (MDI)-based adhesive matrix to fabricate a flame-retardant adhesive for eucalyptus plywood. Cone calorimeter (CONE) analysis demonstrated that the flame-retardant plywood bonded with SPI\/C\/MDI\/C@SiAPP18 achieved the most effective flame-retardant and smoke-suppression performance, and the peak heat release rate, total heat release, and total smoke production were reduced by 23.5%, 20.7%, and 43.9%, respectively, and the release rates of CO and CO2 were also effectively suppressed. Mechanistic analysis indicated that the enhanced flame retardancy was mainly governed by a condensed-phase mechanism, in which phosphorylation and siloxane crosslinking promoted the formation of a compact and thermally stable char layer that protected the underlying material, whereas a gas-phase contribution involving the dilution of flammable volatiles by non-combustible gases (NH3, H2O, and CO2) and possible radical scavenging by phosphorus-containing species is proposed as a plausible complementary pathway inferred from the TGA-FTIR results and the previous literature.<\/jats:p>","DOI":"10.3390\/polym18192312","type":"journal-article","created":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T08:17:54Z","timestamp":1790065074000},"page":"2312","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Formaldehyde-Free, Soy Protein-Based Adhesive with P-N-Si Synergistic Flame Retardancy for Plywood Application"],"prefix":"10.3390","volume":"18","author":[{"given":"Han","family":"Yang","sequence":"first","affiliation":[{"name":"School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China"},{"name":"Hangzhou Municipal Fire and Rescue Bureau, Hangzhou 310008, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6434-5716","authenticated-orcid":false,"given":"Nicolas","family":"Gascoin","sequence":"additional","affiliation":[{"name":"PRISME UR 4229, F-18000 Bourges, France"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"}]},{"given":"Liping","family":"Jiang","sequence":"additional","affiliation":[{"name":"Hangzhou Municipal Fire and Rescue Bureau, Hangzhou 310008, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Xiaofeng","family":"Zhu","sequence":"additional","affiliation":[{"name":"Institute for Smart Ageing, Beijing Academy of Science and Technology, Beijing 100089, China"},{"name":"Beijing Key Laboratory of AgeTech and Health Engineering, Beijing Academy of Science and Technology, Beijing 100089, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"visualization","vocabulary":"credit"}]},{"given":"Xiang","family":"Huang","sequence":"additional","affiliation":[{"name":"Hangzhou Municipal Fire and Rescue Bureau, Hangzhou 310008, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"}]},{"given":"Khaled","family":"Chetehouna","sequence":"additional","affiliation":[{"name":"PRISME UR 4229, F-18000 Bourges, France"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6209-2006","authenticated-orcid":false,"given":"Ruihua","family":"Guo","sequence":"additional","affiliation":[{"name":"Institute for Smart Ageing, Beijing Academy of Science and Technology, Beijing 100089, China"},{"name":"Beijing Key Laboratory of AgeTech and Health Engineering, Beijing Academy of Science and Technology, Beijing 100089, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"122949","DOI":"10.1016\/j.indcrop.2026.122949","article-title":"Fabrication and characterization of multi-functional plywood with flame-retardant, mold-resistant, and dimensionally stable properties via a one-step soaking process","volume":"242","author":"Qin","year":"2026","journal-title":"Ind. 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