2-氢七氟丙烷熄灭聚甲基丙烯酸甲酯燃烧火焰的实验研究  

Experimental Investigations on Suppression of Combustion Flames of Poly(Methyl methacrylate) by 2H-Heptafluoropropane

作　　者：胡永华[1] 李疏芬[1] 

机构地区：[1]中国科学技术大学火灾科学国家重点实验室和化学物理系,安徽合肥230026

出　　处：《火灾科学》2008年第1期34-39,共6页Fire Safety Science

摘　　要：采用二视窗小型燃烧室和数码摄像技术分别研究了2-氢七氟丙烷和二氧化碳对聚甲基丙烯酸甲酯(PMMA)燃烧火焰的熄灭过程;探讨了2-氢七氟丙烷对PMMA的点火延迟时间、火焰形貌和燃烧速率的影响;同时,运用傅立叶变换红外光谱(FTIR)对PMMA熄火表面的化学成份进行了分析。结果发现:极低浓度的2-氢七氟丙烷不仅不能灭火反而还能够促进PMMA的点火和燃烧,但在灭火剂浓度相对较高的情况下,2-氢七氟丙烷抑制样品点火和燃烧的能力要远高于二氧化碳。与二氧化碳灭火剂相比,2-氢七氟丙烷具有灭火浓度低、灭火效率高和灭火速度快等明显优点。此外,FTIR的分析结果显示PMMA熄火表面的化学成份没有明显变化,这表明2-氢七氟丙烷对PMMA燃烧火焰的熄灭作用可能主要是发生在气相中。The extinguishment processes of combustion flames of PMMA by 2H-heptafluoropropane and CO2 were investigated through using a laboratory-scale combustion chamber with two parallel glass windows, and the digital photographing technology. The effects of 2H-heptafluoropropane on the ignition delay time, the shape of combustion flame and the burning rate of PMMA were explored. At the same time, chemical compositions of extinguished surfaces of PMMA at different ambiences were analyzed by FTIR. The results indicated that 2H-heptafluoropropane at extremely low concentration can promote the ignition and combustion of PMMA, but the ability of suppressing sample ignition and combustion by 2H-heptafluoropropane is far higher than that by CO2 when the two inhibitors＇ concentrations are relatively higher. Compared with CO2 fire-suppressing a- gent, 2H-heptafluoropropane possesses some remarkable strongpoints, such as low fire-suppressing concentration, high efficiency of suppressing a flame and quick fire-fighting speed. Moreover, the results of FTIR analysis further show that the existence of 2H-heptafluoropropane hasn＇t obvious effects on the chemical constitution of extinguished surfaces of samples. Therefore, the inhibition of PMMA flame by 2H-heptafluoropropane is likely to mainly happen in gaseous phase.

关 键 词：2-氢七氟丙烷 聚甲基丙烯酸甲酯 燃烧火焰 灭火 傅立叶变换红外光谱 

分 类 号：TK16[动力工程及工程热物理—热能工程]