The urgent demand for fire-safe coatings in bamboo furniture has driven significant progress in developing halogen-free flame-retardant technologies. This study presents a new multi-synergistic flame-retardant hydrogel coating, composed of methylcellulose (MC), polyacrylamide (PAAm), and tetraethyl orthosilicate (TEOS)-pretreated ammonium polyphosphate (SiO₂@APP) for bamboo veneers. The uniformly dispersed SiO₂@APP serves as an acid catalyst and an incombustible gas source, while MC and PAAm act as carbon sources in the fire-resistant C-Si-P-N coating system. Additionally, the hydrogel containing MC and water provides significant heat absorption, improving its flame-retardant efficacy. The limiting oxygen index (LOI) of the resultant hydrogel-coated bamboo (HB) increases significantly from 22.1 % to 55.9 %. Notable reductions of 20.3 % and 53.1 % in the peak heat release rate (PHRR) and total heat release (THR) of the hydrogel-coated bamboo (HB) are observed, respectively, in comparison to the original bamboo. After combustion, the dense hybrid char layer incorporating P, N, and Si effectively impedes heat release and combustible gas diffusion. Additionally, the hydrogel coating exhibits excellent interfacial adhesive strength (125.9 kPa) on the bamboo surface. Through this simple and facile sol-gel preparation process, efficient flame-retardant coatings demonstrate promising potential for biomass-based materials in diverse applications, including furniture, commercial buildings, and industrial uses.

中文翻译：

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用于竹单板的多效阻燃水凝胶涂料


竹家具对防火涂料的迫切需求推动了无卤阻燃技术开发取得重大进展。本研究提出了一种新的多协同阻燃水凝胶涂层，由甲基纤维素 （MC）、聚丙烯酰胺 （PAAm） 和正硅酸四乙酯 （TEOS） 预处理的聚磷酸铵 （SiO₂@APP） 组成，用于竹单板。均匀分散的 SiO₂@APP 用作酸催化剂和不燃气源，而 MC 和 PAAm 在防火 C-Si-P-N 涂料系统中用作碳源。此外，含有 MC 和水的水凝胶具有显著的吸热性，提高了其阻燃效果。所得水凝胶涂层竹子 （HB） 的极限氧指数 （LOI） 从 22.1 % 显著增加到 55.9 %。与原始竹子相比，观察到水凝胶涂层竹子 （HB） 的峰值热释放率 （PHRR） 和总热释放 （THR） 分别显着降低了 20.3% 和 53.1%。燃烧后，含有 P、N 和 Si 的致密混合炭层有效阻止了热量释放和可燃气体扩散。此外，水凝胶涂层在竹子表面表现出优异的界面粘合强度 （125.9 kPa）。通过这种简单易用的溶胶-凝胶制备工艺，高效的阻燃涂料在家具、商业建筑和工业用途等各种应用中显示出生物质基材料的潜力。