The application of conventional aqueous film-forming foam (AFFF) has been severely restricted due to the serious environmental hazard caused by the key component, fluorocarbon surfactants. Environmental-friendly fluorine-free firefighting foams need to be developed urgently. In this study, five silicone surfactants are chosen as key component to prepare fluorine-free firefighting foams. The aqueous solution properties of the fluorine-free firefighting foams are studied in details, including surface tension, interfacial tension, spreading property, viscosity and foaming ability. Foam drainage and foam spread on heptane surface are analyzed. Fire extinguishing and burn-back performance of fluorine-free foams is evaluated based on a small-scale standard method. Particularly, fire extinguishing and burn-back performance of a commercial AFFF is also evaluated as a comparison. Results show that fluorine-free foams cannot form aqueous film on cyclohexane surface, no matter whether spreading coefficient is greater than zero or not. Fluorine-free foams exhibit much better foam stability but worse foam spread property than commercial AFFF. Not all the fluorine-free foams containing silicone surfactant performed as well as AFFF containing fluorocarbon surfactant. Only fluorine-free foam containing silicone surfactant of OFX-5211 shows better fire extinguishing and burn-back performance than AFFF. The higher efficiency of fluorine-free foam in fire extinguishing and burn-back should be attributed to the stronger foam stability.

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基于碳氢化合物和有机硅表面活性剂混合物的环保灭火泡沫研究

传统的水性成膜泡沫（AFFF）由于其关键成分氟碳表面活性剂对环境造成严重危害而受到严重限制。环保无氟消防泡沫亟待开发。在本研究中，选择五种有机硅表面活性剂作为制备无氟消防泡沫的关键组分。详细研究了无氟消防泡沫的水溶液性能，包括表面张力、界面张力、铺展性、粘度和发泡能力。分析了泡沫排放和泡沫在庚烷表面的扩散。基于小规模标准方法评估无氟泡沫的灭火和回燃性能。特别，还评估了商用 AFFF 的灭火和回燃性能作为比较。结果表明，无论铺展系数是否大于零，无氟泡沫都不会在环己烷表面形成水膜。与商业 AFFF 相比，无氟泡沫表现出更好的泡沫稳定性但更差的泡沫扩散性。并非所有含有有机硅表面活性剂的无氟泡沫都与含有氟碳表面活性剂的 AFFF 一样好。只有OFX-5211的含硅表面活性剂的无氟泡沫表现出比AFFF更好的灭火和回烧性能。无氟泡沫灭火和回燃的效率更高，这应该归功于更强的泡沫稳定性。结果表明，无论铺展系数是否大于零，无氟泡沫都不会在环己烷表面形成水膜。与商业 AFFF 相比，无氟泡沫表现出更好的泡沫稳定性但更差的泡沫扩散性。并非所有含有有机硅表面活性剂的无氟泡沫都与含有氟碳表面活性剂的 AFFF 一样好。只有OFX-5211的含硅表面活性剂的无氟泡沫表现出比AFFF更好的灭火和回烧性能。无氟泡沫灭火和回燃的效率更高，这应该归功于更强的泡沫稳定性。结果表明，无论铺展系数是否大于零，无氟泡沫都不会在环己烷表面形成水膜。与商业 AFFF 相比，无氟泡沫表现出更好的泡沫稳定性但更差的泡沫扩散性。并非所有含有有机硅表面活性剂的无氟泡沫都与含有氟碳表面活性剂的 AFFF 一样好。只有OFX-5211的含硅表面活性剂的无氟泡沫表现出比AFFF更好的灭火和回烧性能。无氟泡沫灭火和回燃的效率更高，这应该归功于更强的泡沫稳定性。并非所有含有有机硅表面活性剂的无氟泡沫都与含有氟碳表面活性剂的 AFFF 一样好。只有OFX-5211的含硅表面活性剂的无氟泡沫表现出比AFFF更好的灭火和回烧性能。无氟泡沫灭火和回燃的效率更高，这应该归功于更强的泡沫稳定性。并非所有含有有机硅表面活性剂的无氟泡沫都与含有氟碳表面活性剂的 AFFF 一样好。只有OFX-5211的含硅表面活性剂的无氟泡沫表现出比AFFF更好的灭火和回烧性能。无氟泡沫灭火和回燃的效率更高，这应该归功于更强的泡沫稳定性。