Synthesis of a novel Si-N-S flame retardant and its application on cotton cellulose biomacromolecule

• Published in: International journal of biological macromolecules Vol. 273; no. Pt 2; p. 132775
• Main Authors: Tian, Jialong, Yu, Wenhui, Pan, Jiang, Qi, Zhenming, Lin, Ling, Wang, Jinmei, Wang, Chunxia
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.07.2024
• Subjects: Cellulose - analogs & derivatives; Cellulose - chemistry; Cotton; Cotton Fiber - analysis; Flame retardancy; Flame Retardants - analysis; Flame Retardants - chemical synthesis; Macromolecular Substances - chemical synthesis; Macromolecular Substances - chemistry; Nitrogen - chemistry; Si-N-S; Silicon - chemistry; Spectroscopy, Fourier Transform Infrared; Thermogravimetry; Cotton; Flame retardancy; Si-N-S
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2024.132775

A novel flame retardant containing Si, N, and S elements, ((2-(triethoxysilyl)ethyl)thio)ethan-1-amine hydrochloride (TETEA), was synthesized via a click reaction and characterized using nuclear magnetic resonance spectroscopy (NMR) and fourier transform infrared spectroscopy (FTIR). Subsequently, the flame-retardant cotton fabric was fabricated by sol-gel method. The results indicated that TETEA was successfully loaded on cotton fabric and formed a uniform protective layer on the surface of cotton fabric, exhibiting excellent flame retardancy. The flame-retardant cotton fabric achieved limiting oxygen index (LOI) of 28.3 % and passed vertical combustion test without after-flame or afterglow time at TETEA concentration of 500 g/L. Thermogravimetric analysis revealed that the residual carbon content of the flame-retardant cotton fabric was much higher than that of the control under air and N2 conditions. Besides, the flame-retardant cotton fabric was not ignited in cone calorimeter test with an external heat flux of 35 kW/m2. The peak heat release rate and the total heat release decreased from 133.4 kW/m2 to 25.8 kW/m2 and from 26.46 MJ/m2 to 17.96 MJ/m2, respectively. This phosphorus-free flame retardant offers a simplified synthesis process without adverse environmental impacts, opening up a new avenue for the development environmentally friendly flame retardants compared to traditional alternatives. •A new phosphorus-free flame retardant was synthesized under solvent-free conditions.•The preparation process was simple, cost-effective and environmentally friendly.•Cotton fabric achieved the LOI of 28.3 % and passed vertical combustion test.•The hydrophobicity of the flame-retardant cotton fabric was also enhanced.