Cotton fabrics are highly flammable, significantly hampering their availabilities and even leading to unacceptable adverse consequences. Flame-retardant coating is deemed to be the most promising strategy to overcome this problem. In this work, a double-layered ammonium alginate/phytic acid@trimethoxy(octyl)silane (AA/PA@TMOS) flame-retardant coating for cotton fabrics was developed. The AA layer protected the cotton fabric from PA to preserve the robustness of the cotton fabric and assisted PA in generating a stable and dense char layer, while the PA@TMOS layer inherited both flame retardancy and wash durability of their ingredients. Consequently, the AA/PA@TMOS-C achieved a high limiting oxygen index of 38.7% and low peak smoke produce rate of 0.0014 m 2 /s, demonstrating low-smoke flame retardancy. Even after 12 laundering cycles, the developed AA/PA@TMOS-C still showed incombustibility in air. The integration of extraordinary flame retardancy, smoke suppression and durability on the developed double-layered coating rendered its promising potential as a compelling flame-retardant coating for cotton fabrics or other materials.
Yanghang Liu,Lizhi Wang,Zirun Zhan,Yu Jiang,Xun Zhang,Yunhe Li,Xin Zhong,Dan Yu,Wei Wang
Real-time visual detection of ammonia (NH₃) is crucial for environmental safety and food quality, yet traditional sensors often suffer from slow response, poor selectivity, and limited adaptability. Here, we innovatively report an ammonium alginate (AL) and cellulose nanofiber-based colorimetric aerogel (APPC aerogel) with a sea anemone-inspired structure for rapid, sensitive, and reversible NH₃ detection. The aerogel is prepared by embedding a sulfonated indole photoacid (PMU H) into a matrix of AL, cellulose nanofibers (CNF), and phytic acid (PA), cast into a 3D-printed template, and directionally frozen to form an ordered porous bionic structure. Upon NH₃ exposure, PMU-H undergoes fast, reversible proton transfer and enol-keto tautomerization, producing a color change from yellow to purplish-red within 5 s. The aerogel shows a detection limit of 0.65 ppm, a linear range of 1–250 ppm, and maintains performance over 50 cycles. FTIR and DFT analyses reveal the sensing mechanism. The material remains stable under humidity, temperature variations, and complex gases, enabling effective visual monitoring of NH₃ during seafood spoilage and offering promise for food packaging, environmental monitoring, and safety applications.
危险品化学品经营许可证（带存储）