热解条件对典型杂原子橡胶干扰火场残留物检验鉴定的影响研究  

Research on the influence of pyrolysis condition on the interferenceof typical heteroatom rubber to fire debris analysis

作　　者：钱佩雯 张茜茜 李秋璠梓 张冠男[2] 金静 蒋宇杭 孙振文[2] QIAN Peiwen;ZHANG Qianqian;LIQIU Fanzi;ZHANG Guannan;JIN Jing;JIANG Yuhang;SUN Zhenwen(Chinese People’s Police University,Langfang 065000,China;Institute of Forensic Science,Ministry of Public Security,Beijing 100038,China)

机构地区：[1]中国人民警察大学,廊坊065000 [2]公安部物证鉴定中心,北京100038

出　　处：《火灾科学》2023年第2期67-76,共10页Fire Safety Science

基　　金：河北省自然科学基金面上项目(E2021507001);中国人民警察大学校级科研重点专项科研重点攻关课题(ZDZX202003)。

摘　　要：为探究杂原子的存在以及热解条件对橡胶干扰汽油检验鉴定程度的影响,选取火场常见的氯丁橡胶和丁腈橡胶作为研究对象,同时结合燃烧化学理论,借助锥形量热仪模拟火场条件制备了不同热辐射强度下杂原子橡胶的热解/燃烧残留物,采用气相色谱-质谱技术分析了产物中烷烃类、烷基苯、茚满及稠环芳烃类组分的变化情况及其对汽油检验鉴定的干扰性。结果表明:氯丁橡胶和丁腈橡胶中均能检出十一烷、十三烷、十五烷、甲苯、C2苯、C3苯、C4苯、茚满、甲基茚满、二甲基茚、乙基茚满、萘、甲基萘和二甲基萘等特征组分,对汽油检验鉴定干扰性较大。随着热解程度的增加,氯丁橡胶和丁腈橡胶热解产物中烷烃类组分数的减少,烷基苯类组分中C2苯未发生变化,C3苯和C4苯组分的数量减少,而茚满类和稠环芳烃类组分丰度降低,且橡胶中的杂原子易与烷烃和苯及其同系物发生取代反应,最终生成含杂原子的热解产物,可作为确定杂原子橡胶存在的依据。本研究分析比较了不同热解条件下氯丁橡胶和丁腈橡胶对汽油燃烧残留物检验鉴定的干扰性,可为分析杂原子橡胶的基质干扰性及全面科学理解火场基质干扰提供科学参考。It is of great theoretical and practical significance to study matrix interference on fire debris analysis at fire scenes.According to the previous results of our group,it is known that olefin rubber caused remarkable interference on gasoline identification.To further explore the influence of heteroatoms on rubber interference on gasoline identification,neoprene rubber and NBR(nitrile butadiene rubber)rubber were selected and the corresponding pyrolysis/combustion residues under different radiation intensities were prepared via cone calorimeter to stimulate fire scenes.Combined with combustion chemistry theory,the interference on gasoline identifications through gas chromatography mass spectrometry was analyzed based on the results of alkanes,alkylbenzenes,indanes and condensed ring aromatics in the residues.The characteristic compounds,including undecane,tridecane,pentadecane,toluene,C2-alkylbenzenes,C3-alkylbenzenes,C4-alkylbenzenes,indane,methylindane,dimethylindene,ethylindane,naphthalene,methylnaphthalene and dimethylnaphthalene,can be detected in both residues of neoprene rubber and NBR rubber,which caused nonnegligible interference of‘false positive’interference on gasoline residue.With the increase of pyrolysis degree,the alkylbenzenes in neoprene rubber and NBR rubber residues remained stable,while it became rather hard to extract indanes and condensed ring aromatics in the residues then.Moreover,the presence of heteroatom components is easy to substitute with alkanes,benzene and their homologues,and finally generate pyrolysis products containing heteroatom,which can be used as the basis for determining the existence of heteroatom rubber.Through the study of the interference from neoprene rubber and NBR rubber on gasoline identifications under different pyrolysis degrees,the study herein provided important references for analyzing matrix interference and eliminating matrix interference from the typical heteroatom rubbers.

关 键 词：火场残留物 助燃剂检验鉴定 基质干扰 杂原子橡胶 热解程度 

分 类 号：X928.7[环境科学与工程—安全科学] X915.5