Abstract:

In this paper, polyether-modified trisiloxane and CTAB as surfactants, and nano-magnesium hydroxide and xanthan gum as stabilizing agent were prepared for preparation of fluorine-free foam fire extinguishing agent. L₉(3⁴) orthogonal table was used to analyze surface tension, foaming performance and foam stability of foam solution, and orthogonally optimized foam formula was selected for fire fighting and anti-burning experimental research. The results showed that the viscosity of the compound system was low between 1.00—1.21mPa·s. The foam solution composed of CTAB with mass fraction of 0.8% and 12% polyether-modified trisiloxane had the lowest surface tension of 19.73mN/m. Polyether-modified trisiloxane cooperated with CTAB to enhance the solution foaming performance and foam stability. When the mass fraction of nanometer magnesium hydroxide was 0.5%, the solution foaming was highly optimal, reaching 207mm, and the 25% solution time increased from 205s to 216s. The foam fire extinguishing agent prepared with the mass fraction of 1.2% CTAB, 12% polyether-modified trisiloxane, 0.5% nano-magnesium hydroxide and 0.05% xanthan gum was used to extinguish the n-heptane fire with the oil pan area of 0.25m², and the fire extinguishing time was 107s with the anti-burning time of 372s.

Key words: nano-magnesium hydroxide, surfactant, foam stability, fire extinguishing performance, fluorine-free foam extinguishing agent

摘要：

以聚醚改性三硅氧烷、CTAB为表面活性剂，以纳米氢氧化镁、黄原胶为稳泡剂制备无氟泡沫灭火剂，采用L₉(3⁴)正交表分析泡沫溶液表面张力、发泡性能及稳泡性能，选用正交优化后的泡沫配方进行灭火和抗烧实验研究。研究结果表明：复配体系泡沫溶液黏度较低，在1.00~1.21mPa·s之间；由质量分数为0.8%的CTAB与12%的聚醚改性三硅氧烷组成的泡沫溶液表面张力最低，为19.73mN/m；聚醚改性三硅氧烷与CTAB协同作用，增强了溶液发泡性能与泡沫稳定性，当纳米氢氧化镁的质量分数为0.5%时，溶液的发泡高度最优，达到207mm，25%析液时间从205s增长到216s；用质量分数为1.2% CTAB、12%聚醚改性三硅氧烷、0.5%纳米氢氧化镁及0.05%黄原胶制备的泡沫灭火剂扑灭油盘面积为0.25m²的正庚烷火，灭火时间为107s，抗烧时间达到372s。

关键词: 纳米氢氧化镁, 表面活性剂, 泡沫稳定性, 灭火性能, 无氟泡沫灭火剂