灭火添加剂对木结构润湿性的影响研究

Effect of fire extinguishing additives on wettability of wooden structure

为寻找适用于扑灭木材火灾的水系灭火剂添加剂,通过分子模拟方法,构建水环境下的纤维素-添加剂吸附体系,以研究添加剂在纤维素表面的润湿机制。将两性离子碳氢表面活性剂BS-12、离子型碳氟表面活性剂Capstone1157、非离子碳氢表面活性剂AEO 9等3种灭火添加剂介入纤维素润湿体系,在298和498 K的条件下,模拟纤维素-添加剂体系对水分子的吸附过程,探讨其润湿性和界面行为。模拟结果表明:尽管温度不同,当3种添加剂介入纤维素润湿体系中时,均会明显增强体系对水分子的吸附性,吸附量均随着添加剂体积分数的增加而增加,最后趋于稳定。润湿过程中,添加剂自身静电势引起的体系内静电力作用是吸附行为的主要驱动力,其吸附方向的垂直程度决定了其吸附能力的强弱。接触角测量结果与3种添加剂体系的水分子吸附量模拟结果具有高度的一致性,BS-12和Capstone1157对纤维素润湿性的提升效果优于AEO 9。

In order to find water-based fire extinguishing agent additives suitable for fighting wood fires,a cellulose-additive adsorption system under water environment was constructed by molecular simulation method to study the wetting mechanism of additives on the cellulose surface.Three fire extinguishing additives,amphoteric hydrocarbon surfactant BS-12,ionic fluorocarbon surfactant Capstone1157,and nonionic hydrocarbon surfactant AEO 9,were intervened in the cellulose wetting system,and the adsorption simulation of the cellulose-additive system on water molecules was realized at 298 and 498 K to explore the wetting mechanism and interfacial behavior.The simulation results show that,despite the different temperatures,the three additives involved in the cellulose wetting system significantly enhance the adsorption of water molecules,and the adsorption amount increases with the increase in the volume fraction of additives,and finally tends to be stable.During the wetting process,the electrostatic force in the system caused by the additive's own electrostatic potential is the main driving force of the adsorption behavior,and the vertical degree of its adsorption direction determines the strength of its adsorption capacity.The contact angle measurements are in high agreement with the simulated results of water molecule adsorption for the three additive systems,and BS-12 and Capstone1157 are more effective than AEO 9 in enhancing the wettability of cellulose.