{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T12:25:54Z","timestamp":1789129554344,"version":"build-2803163510"},"reference-count":42,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T00:00:00Z","timestamp":1789084800000},"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":["Gels"],"abstract":"<jats:p>Soybean protein isolate (SPI) adhesives are eco-friendly but suffer from poor water resistance and bonding strength. Waterborne epoxy (WE) can effectively improve these properties; however, WE-modified SPI adhesives can hardly satisfy the growing stringent flame-retardant demands for plywood. Herein, we report a composite adhesive (SPI\/20WE\/THPS@CS\/MMT) that simultaneously exhibits favorable flame retardancy and dry and wet shear strengths. In this system, a phosphorus-, nitrogen-, and sulfur-containing polyelectrolyte complex (THPS@CS) is fabricated by vacuum-drying an ionically crosslinked polyelectrolyte hydrogel derived from bis[tetrakis(hydroxymethyl)phosphonium] sulfate (THPS) and chitosan (CS) and subsequently incorporated into the SPI\/WE matrix (SPI\/20WE) together with montmorillonite (MMT). The plywood bonded with SPI\/20WE\/THPS@CS\/MMT achieves a limiting oxygen index (LOI) of 28.0% and shows significantly reduced heat release in cone calorimeter tests. Meanwhile, the resultant plywood possesses high dry and wet shear strengths that fulfill the interior-use plywood criteria specified in GB\/T 9846\u20132015. This work offers new insights into the design and fabrication of high-performance eco-friendly plywood adhesives.<\/jats:p>","DOI":"10.3390\/gels12090834","type":"journal-article","created":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T10:51:37Z","timestamp":1789123897000},"page":"834","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Polyelectrolyte Complex\/MMT Hybrid for SPI\/WE Adhesives with Balanced Flame Retardancy and Shear Strength"],"prefix":"10.3390","volume":"12","author":[{"given":"Han","family":"Yang","sequence":"first","affiliation":[{"name":"School of Materials Science and Engineering, Zhejiang University, Hangzhou 310058, China"},{"name":"Zhejiang Provincial Fire and Rescue Bureau, Hangzhou 310008, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuxin","family":"Luo","sequence":"additional","affiliation":[{"name":"School of Materials Science & Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiyi","family":"Ding","sequence":"additional","affiliation":[{"name":"Zhejiang Provincial Fire and Rescue Bureau, Hangzhou 310008, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunchun","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Zhejiang University, Hangzhou 310058, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9931-2765","authenticated-orcid":false,"given":"Tao","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Product Design, School of Art & Design, Zhejiang Sci-Tech University, Hangzhou 310018, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Oni, O.V., Lawrence, M.A., Zappi, M.E., and Chirdon, W.M. 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