火场汽油检验鉴定基质干扰官能团的溯源研究  

Study on Functional Groups of Matrix Interference to Gasoline Identification for Fire Investigation

作　　者：张茜茜 臧政哲 金静 殷果 胡语嫣 钱佩雯 李秋璠梓 蒋宇杭 ZHANG Qian-Qian;ZANG Zheng-Zhe;JIN Jing;YIN Guo;HU Yu-Yan;QIAN Pei-Wen;LI Qiu-Fan-Zi;JIANG Yu-Hang(The Graduate School,China People's Police University,Langfang 065000,China;School of Criminal Investigation,China People's Police University,Langfang 065000,China)

机构地区：[1]中国人民警察大学研究生院,廊坊065000 [2]中国人民警察大学侦查学院,廊坊065000

出　　处：《分析化学》2024年第3期389-397,共9页Chinese Journal of Analytical Chemistry

基　　金：中国人民警察大学重点专项课题项目(No.ZDZX20200);河北省自然科学基金项目(No.E2021507001)资助。

摘　　要：火场助燃剂检验鉴定的基质干扰一直是法庭科学领域研究的重点和难点。为进一步探究C=C是否为基质干扰官能团,采用气相色谱-质谱联用(GC-MS)技术和裂解气相色谱-质谱联用(Py-GC/MS)技术,分别从化学结构和裂解过程的角度定性分析加氢处理(饱和丁二烯双键)前后的苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)和苯乙烯-乙烯-丁烯-苯乙烯(SEBS)燃烧/裂解产物对汽油鉴定的影响,利用二者的烷基苯、茚满类和稠环芳烃类组分提取离子流色谱图(EICs)与汽油燃烧残留物对应的EICs的谱图相似度对两类材料的干扰程度进行定量分析。定性和定量分析结果均表明,SEBS对汽油鉴定的干扰较小:相较于SBS,在SEBS燃烧残留物中无法检出茚满、二甲基茚满及二甲基萘等特征组分,并且烷基苯、茚满类和稠环芳烃类特征组分的相对含量均明显减少,即SEBS造成“假阳性”干扰的程度更低;加载汽油混合燃烧后,SBS和SEBS残留物的特征组分相对峰面积比例与汽油燃烧残留物仍存在较大差异,容易造成“假阴性”的结论;SEBS裂解过程中产生的含双键结构的裂解产物更少。结合SBS和SEBS双键结构的差异和裂解产物的差异,验证了C=C结构与汽油鉴定中的基质干扰程度存在关联。本研究结果为进一步了解火场残留物检验鉴定中产生基质干扰的官能团提供了重要参考。Matrix interference in inspection and identification of accelerant used in arson has always been a focus and difficulty in the field of forensic science.In this work,to further investigate whether carbon-carbon double bonds were functional groups that caused matrix interference,gas chromatography-mass spectrometry(GC-MS)and pyrolysis gas chromatography-mass spectrometry(Py-GC/MS)were used to qualitatively analyze the combustion/cracking products of styrene butadiene styrene block copolymer(SBS,before hydrogenation)and styrene ethylene butene styrene(SEBS,after hydrogenation saturated butadiene carbon-carbon double bonds)from the perspectives of chemical structure and cracking process,and their interference with gasoline identification.Quantitative analysis was conducted on the interference degree of the two types of materials using the similarity of ion flow chromatography(EICs)extracted from alkylbenzene,indene,and polycyclic aromatic hydrocarbon components and the EICs corresponding to gasoline combustion residues.Both qualitative and quantitative results indicated that SEBS had less interference in gasoline identification.Compared to SBS,the characteristic components such as indene,dimethylindene and dimethylnaphthalene could not be detected in SEBS combustion residues,and the relative content of alkyl benzene,indene,and polycyclic aromatic hydrocarbon characteristic components was significantly reduced,indicating that SEBS had a lower degree of"false positive"interference.After loading gasoline for mixed combustion,a significant dfference in the relative peak area ratio of characteristic components could be found between SBS and SEBS residues and gasoline combustion residues,which could easily lead to a"false negative"conclusion.During the cracking process of SEBS,fewer cracking products with double bond structures were produced.The correlation between the carbon-carbon double bond structure and the degree of matrix interference in gasoline identification was verified by combining the differences in SBS and S

关 键 词：火场残留物分析 基质干扰 汽油鉴定 碳碳双键结构 苯乙烯-丁二烯-苯乙烯嵌段共聚物 氢化苯乙烯-丁二烯-苯乙烯嵌段共聚物 

分 类 号：D918.9[政治法律—法学] O657.63[理学—分析化学]