Fe、Mn掺杂APP/硅凝胶对泡桐的阻燃抑烟性能

Flame retardancy and smoke suppression of APP/silicon gel doped with Fe and Mn on Paulownia

【目的】利用氮-磷阻燃剂和金属盐/介孔凝胶的高效协同阻燃作用,减少木质材料热量释放的同时,降低其烟雾毒气,探索木质材料高效阻燃基础上解决火灾烟雾毒气问题。【方法】通过真空加压浸渍处理将硅源前驱物和APP的复合阻燃剂负载于泡桐细胞腔中,并原位构建APP/硅凝胶复合体系。采用SEM、CONE、TGA等测试与分析手段研究APP/硅凝胶复合体系对泡桐的阻燃减毒作用。【结果】SEM显示掺杂改性的凝胶颗粒成功地沉积在木材导管和细胞腔中,与细胞壁结合紧密。CONE试验表明,APP/硅凝胶能高效抑制木材的热释放,但却无法减少烟雾毒气的生成,这一直是APP阻燃剂需要克服的缺点。Fe、Mn掺杂的PF-Fe/APP/Gel与PF-Mn/APP/Gel的PHRR、THR等热释放值比PF-APP/Gel试样下降更为显著,其THR较于泡桐素材PF-UN也分别下降了66.05%、75.62%,比PF-APP/Gel减少了7.7、10.8 MJ/m2。同时PF-Fe/APP/Gel与PF-Mn/APP/Gel表现了优异抑烟作用,不仅其TSP2较PF-UN分别下降了13.9%、13.43%,SPR降低了64.9%、66.2%,其SPR、TSP、YCO也明显低于PF-APP/Gel。由TGA可知,APP的加入可明显提高浸渍泡桐成炭量,使其在更低的温区成炭,但PF-APP/Gel在600~800℃高温区稳定性下降,Fe、Mn掺杂可提高试样在高温下的稳定性。PF-Fe/APP/Gel和PF-Mn/APP/Gel在800℃的残炭量从PF-UN的19.9%上升到38.3%、38.2%,比PF-APP/Gel也提高约4%。残炭分析发现PF-Fe/APP/Gel和PF-Mn/APP/Gel的CONE试验残炭形成了一个绵延致密的整体炭层。【结论】研究表明,在木材催化成炭的过程中,Fe、Mn盐能明显促进APP/硅凝胶与泡桐的成炭作用,形成的Fe(Mn)-Si-磷酸盐炭层质量高,是抵挡材料的热量释放和烟气产生的致密坚固屏障。

【Objective】To use the efficient synergistic flame retardant effect of nitrogen-phosphorus flame retardant and metal salt/mesoporous gel to reduce the heat release of wood material while reducing its smoke toxic gas,and to explore the efficient flame retardant basis of wood material to solve the fire smoke toxic gas problem.【Method】The composite flame retardant of silica source precursors and APP was loaded into the cell cavity of Paulownia by vacuum pressurized impregnation treatment,and the APP/silica gel composite system was constructed in situ.SEM,CONE,TGA and other testing and analysis methods were used to study the flame retardant and toxicity reduction effects of APP/silica gel composite system on phellodendron.【Result】SEM showed that the doped modified gel particles were successfully deposited in the wood ducts and cell cavities and tightly bonded to the cell walls.CONE experiments showed that APP/silica gel could efficiently inhibit the heat release from wood,but could not reduce the generation of smoke toxic gas,which has been a shortcoming to be overcome by APP flame retardant.Fe,Mn doped PF-Fe/APP/Gel and PF-Mn.The heat release values of PHRR and THR of PF-Fe/APP/Gel decreased more significantly than those of PFAPP/Gel specimens,and its THR also decreased by 66.05%and 75.62%respectively compared to PF-UN of blister material,and decreased by 7.7 MJ/m2 and 10.8 MJ/m2 compared to PF-APP/Gel.Meanwhile,PF-Fe/APP/Gel and PF-Mn/APP/Gel.The TGA showed that the addition of APP significantly improved the char formation of impregnated soaking pine at a lower temperature zone into carbon,but the stability of PF-APP/Gel in the high temperature zone of 600-800°C decreased,and Fe and Mn doping improved the stability of the specimens at high temperature.The residual carbon amount of PF-Fe/APP/Gel and PF-Mn/APP/Gel at 800°C increased from 19.9%to 38.3%and 38.2%for PF-UN,which was also higher than that of PF-APP/Gel about 4%higher than PF-APP/Gel.The residual carbon analysis revealed that the residual carbon of PF-Fe/APP/Gel and PF-Mn/APP/Gel in the CONE experiment formed a stretched and dense overall carbon layer.【Conclusion】It is shown that Fe and Mn salts can significantly promote the char formation of APP/Si-gel with puffballs in the process of wood catalytic char formation,and the Fe(Mn)-Si-phosphate char layer formed is of high quality and is a dense and strong barrier against heat release and smoke generation from the material.