高分子燃燒與熱裂解反應之研究

A Study of Polymers Combustion and Pyrolysis

林如瑩(Lin Ju Ying)

指導教授 ： 廖義田

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2006年)

摘要

以往火場殘跡促燃劑之分析是使用氣相層析法（GC），將火場殘跡之萃取物直接以GC分析後，再將層析圖與標準品層析圖做譜型之比對，以判定火災現場殘跡中是否含有促燃劑。此法之最大缺點係由於現場裂解物之干擾對證物所造成誤判。現今以氣相層析質譜法（GC/MS）之技術，配合標的化合物法，做促燃劑之確認，此法雖已可大大降低基質干擾之問題，但因火場中之日常用品，經高溫燃燒、裂解後，常會產生大量的可燃性氣體及其他產物，而這些產物很有可能會對縱火案件之證物判定上造成干擾。
本研究針對塑膠中較為泛用的聚苯乙烯（PS）及丙烯晴-丁二烯-苯乙烯（ABS）來探討，了解此兩類原料及加工後之產品燃燒、裂解後對火場殘跡鑑定之影響。實驗結果發現PS及ABS產品之原料和產品，在未燃燒、燃燒及高溫熱裂解後，以GC/MS分析所得結果，均會產生芳香族碳氫化合物成分，會在判定火場殘跡中之促燃劑時造成干擾。
另以MS的選擇離子式監測模式（SIM）分析上述高分子聚合物，針對汽油標的化合物成分作掃描，以進一步了解是否含有汽油成分，並可了解這些殘跡中含有哪些成分可能會造成鑑定上之干擾。經實驗發現此兩類原料及加工後之產品雖含有部分汽油標的化合物成分，但均無法完全符合汽油的標的化合物成分，故使用SIM方法可作為檢測汽油成分之再次確認方式。

關鍵字

火場殘跡 ； GC/MS ； 促燃劑 ； PS ； ABS ； SIM

並列摘要

In the past, Gas Chromatography (GC) was applied in the analysis of the accelerants in the fire debris. The chromatogram of the fire debris is compared with the standard sample to examine whether the accelerants exist or not. The maximum drawback of this approach is the evidence that may be interfered from the pyrolysis products and lead erroneous judgment. Nowadays, gas chromatography-mass spectrometry (GC/MS) tied in with Target Compound Chromatography (TCC) is used to do the same work. Despite this approach can greatly diminish the influence of interference from substrate. However, the articles for daily use blazed or cracked in the conflagration could produce a great deal of flammability gas and other products, which may cause interference with evidences of the police cases of arson and result in erroneous judgment.
In this study, the degradation behaviors of PS and ABS were investigated to understand the effect of the combustion and pyrolysis of the two materials. The experimental results show that not only the PS and ABS but also the products made from PS and ABS produce aromatic compounds regardless of being treated with un-combustion, combustion and pyrolysis. Those aromatic compounds may affect the judgment of the accelerants in the fire debris.
Moreover, the above polymers were analyzed by selected ion monitoring (SIM) model in mass spectrometry. This analysis is to investigate whether the composition of gasoline exist and understand which compounds may result in the interference of the examination. It is found that the two series of materials and manufactured products only contain part of the composition in target compound of gasoline; however, their composition does not fit with those in target compound of gasoline completely. Hence, the use of SIM method could be an good approach to double check the composition of gasoline.

並列關鍵字

fire debris ； GC/MS ； accelerant ； PS ； ABS ； SIM

參考文獻

【38】黃敬德、謝有容，"固相微萃取技術之原理及其應用"，化學，第56卷第4期，1998，第311-318頁。

【1】D.C. Mann , ”Comparison of Automotive Gasolines using Capillary Gas Chromatography.Ⅱ.Limitations of Automotive Gasolines Comparisons in Casework,” Journal of Forensic Sciences Vol.32 , 1987 , pp616-628.

【2】J.P. Jackowski , ”The Incidence of Ignitable Liquid Residues in Fire Debris as Determined by a Sensitive and Comprehensive Analytical Scheme,” Journal of Forensic Sciences Vol.42 , 1997 , pp828-832.

【6】D.Drysdale,An Introduction to Fire Dynamics , Chichestwe: John Wiley and Sons, 1985.

【8】J.D.DeHaan , Kirk’s Fire Investigation ,N.J.:Upper Saddle River, 1997 , pp38-67.