裂解气相色谱-质谱法检测常见塑料制品高聚物

Analysis of Common Plastic Products by Pyrolysis-gas Chromatography/Mass Spectrometry

目的运用裂解气相色谱-质谱法(Py-GC/MS)对常见不同材质塑料制品的主体成分进行分析,并对每种塑料的裂解产物进行解析,为相似塑料物证的比对分析奠定基础。方法建立了塑料制品的Py-GC/MS分析方法,并对10种常见塑料制品进行分析,解析其裂解总离子流图,确认这10种塑料制品的主要裂解产物和主体成分,同时考察了裂解重复性。结果 10种塑料制品有9种可根据裂解总离子流图确认其主体成分,分别是聚丙烯、聚苯乙烯、聚碳酸酯、ABS塑料、聚氯乙烯、乙烯-乙酸乙烯共聚物,与标准谱库的匹配度均在81%以上。结论运用PyGC/MS法检测塑料物证,裂解产物各组分的分离度较好,测试结果的重现性较好。该方法所需试样量少,无需任何样品前处理,减少了因前处理带来的测试误差。该研究为犯罪现场不同来源的塑料物证的比对分析提供了可行方法。

Objective To establish a new method for the comparative analysis of plastic samples by pyrolysis -gas chromatography/mass spectrometry （Py-GC/MS）. Method The Py-GC/MS method was established and the repeatability was validated. Ten kinds of common plastic products are analyzed. The main pyrolyzed compounds of each sample were identified, and the polymers of the ten plastic samples were determined through library search. Results Nine out of the ten samples were identified as PP,PS,PC,ABS, PVC and EVA plastics, respectively, with similarities no less than 819 . Conclusion The established Py-GC/MS method is suitable for plastic analysis. It is sensitive and of good repeatability. The solid sample could be analyzed directly, which reduces the error brought by the sample preparation procedure. This study provides a practical method for the comparative analysis of plastic samples in trace evidence examination.