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61.
62.
We undertook numerical and experimental studies to develop a better incineration method for the destruction of CC14. A phenomenological model for the turbulent reaction of CC14, including a flame inhibition feature, has been successfully incorporated into a commercial code, simulating the incineration
processes of this compound. The gaseous flow solution was obtained using SIMPLEST, a derivative of Patankar’s SIMPLE algorithm,
with a k-ε turbulence model. A modified fast chemistry turbulent reaction model was developed to describe the flame inhibition
due to the presence of CC14, considering the corresponding burning velocity data of these mixtures. An experiment was carried out on a 5.2 kW laboratory
scale, transportable, cavity-type incinerator, which warrants a sufficient residence time and effective turbulent mixing by
the formation of a strong recirculation region in a combustor. To this end, the specific configuration of the incinerator
was manufactured to consist of two opposing jets and a rearward facing step. The calculated data were in close agreement with
the experimental data for the concentrations of major species, such as CCI4 and HCl, together with the temperature profiles. The experimental test gave the desired DRE of above 99.99%. 相似文献
63.
Three kinds of organically modified Na+-montmorillonites (OMMTs), including two kinds of octadecylammonium modified montmorillonite with different contents of octadecylammonium and a kind of sodium dodecylsulfonate (SDSo) modified montmorillonite, were used to prepare polyamide 12 (PA12)/OMMT nanocomposites. Effects of the modifiers on degradation and fire retardancy of PA12/OMMT nanocomposites were investigated. Acid sites formed in cationic surfactant modified MMT via Hoffman decomposition could accelerate degradation of PA12 at high temperature. However, catalytic effect of the acid sites on carbonization of the degradation products promoted char barrier formation, which reduced heat release rate (HRR). Higher content of cationic surfactant in OMMT is beneficial to fire retardancy of PA12 nanocomposites and the dispersion states of OMMT have assistant effects. In contrast, Na+-montmorillonite (Na-MMT) and anionic surfactant modified MMT (a-MMT) could not form acid sites on the MMT layers; in this case, fire retardancy of PA12/Na-MMT appears to have no improvement and PA12/a-MMT appears to have limited improvement. 相似文献
64.
65.
马来酸酐接枝聚乙烯对无卤阻燃PE-HD护套料的改性研究 总被引:3,自引:0,他引:3
研究了马来酸酐接枝聚乙烯对无卤抑烟阻燃PE-HD护套料的改性效果,并进行了增韧机理上的探讨。采用扫描电镜对复合材料进行了断面观察,并测试了材料的力学性能、流变性能、耐热性能和氧指数。结果表明,马来酸酐接枝聚乙烯能够极大地提高复合材料的界面相容性,增强材料的界面相互作用,提高阻燃剂微粒在树脂基体中的分散效果,同时形成了一个可塑性界面层,所以能够提高材料的韧性。 相似文献
66.
Tomoyuki Ishikawa Kenji Takasa Takehiko Yamashita Kohshiroh Mizuno Kunihiko Takeda 《应用聚合物科学杂志》2007,104(1):156-161
The thermal behaviors and the flame‐retardancy of styrene–ethylene–butadiene–styrene–block copolymer containing various additives were studied. The combustion was measured by the Underwriter laboratory (UL) test and cone calorimeter test and thermogravimetric analysis and program‐mass spectroscopy were applied to analyze the thermal behaviors. The blend with halogen additives showed the best result in the UL test. However, the blend with red‐phosphorous was the best in the cone calorimeter test. As the styrene sequence in the copolymer tended to degradate at a lower temperature, the major scission products spouted out from the polymer surface originated from polystyrene. The shorter the ignition times of the blends with red‐phosphorous were, the lower the peak heat release rates were. It was an interesting phenomenon because it suggested that the chemical structure of the residue changed to more stable polymers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 156–161, 2007 相似文献
67.
利用锥形量热仪对添加了不同阻燃剂的软质聚氨酯泡沫,在25kW/m^2下,其热释放速率、产烟量、一氧化碳产生量、二氧化碳产生量和点燃时间等进行了试验研究。结果表明,含氯化铵的聚氨酯泡沫燃烧时热释放速率最小,仅是未经阻燃处理的聚氨酯泡沫的热释放速率的11.5%;含硫酸铵的聚氨酯泡沫的产烟量最少,仅是未经阻燃处理的聚氨酯泡沫的产烟量的6.4%;含氯化铵的聚氨酯泡沫燃烧时产生的一氧化碳和二氧化碳都是最少的,分别是未经阻燃处理的聚氨酯泡沫的2,4%和1.6%;点燃时间最长的是含四硼酸钠的聚氨酯泡沫,几乎是未经阻燃处理的聚氨酯泡沫的15倍,其它阻燃剂对聚氨酯泡沫的燃烧性能都有不同程度的影响。 相似文献
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69.
采用线性低密度聚乙烯(LLDPE)、低密度聚乙烯(LDPE)作为阻燃体系的主体,用表面处理过的氢氧化镁(Mg(OH)2)作主阻燃剂,微胶囊化红磷作阻燃增效剂,重点探讨了Mg(OH)2和微胶囊化红磷的阻燃效果。结果表明:Mg(OH)2与红磷并用具有良好的协同效应,是LLDPE/LDPE的高效阻燃体系。 相似文献
70.
采用熔融共混法制备了纳米锡酸锌/丙烯腈-丁二烯-苯乙烯共聚物(ABS)/聚氯乙烯(PVC)复合材料。并对复合材料的冲击强度、阻燃性能进行了测试。结果表明,纳米锡酸锌不但可以提高复合材料的缺口冲击强度,还可以改善复合材料的抑烟阻燃性能。特别是当纳米锡酸锌添加量为6份时,复合材料的阻燃抑烟性能最佳。与未添加纳米填料时相比,纳米锡酸锌/ABS/PVC复合材料的缺口冲击强度达到69.93 kJ/m~2,提高幅度达49.71%。扫描电镜(SEM)分析表明,当纳米锡酸锌在6份时,其在复合材料中呈纳米级分散,且与塑料基体结合良好。 相似文献