Grieve M C, Griffin R M
KT 33 Forensic Science Institute, Wiesbaden, Germany.
Sci Justice. 1999 Jul-Sep;39(3):151-62. doi: 10.1016/S1355-0306(99)72040-X.
This study describes the characteristics of modacrylic fibres and includes over 80 samples (previous and current) representing 15 trade names. Fibre morphology was examined using brightfield microscopy. Signs of elongation were determined using polarised light microscopy. Fibre cross sections were also examined. The generic class of fibre was divided into sub groups using polymer composition as determined by FTIR-microscopy. Microscopically, some modacrylic fibres cannot be distinguished from acrylic fibres. Others display unusual optical and morphological features which are a strong indication of their generic class. The infrared spectra provide information about the co-monomer, termonomers added to produced dye sites, the presence of solvent residue, dyes, and additives, e.g. flame retardant material. The infrared spectra should always be recorded before and after any thin layer chromatographic examination of the dye, otherwise peaks attributable to dyes, which may be a valuable comparative feature in casework will be lost.
本研究描述了变性腈纶纤维的特性，包括代表15个商品名的80多个（既往和当前的）样本。使用明场显微镜检查纤维形态。使用偏振光显微镜确定伸长迹象。还检查了纤维横截面。根据傅里叶变换红外显微镜测定的聚合物组成，将纤维的通用类别分为亚组。在显微镜下，一些变性腈纶纤维无法与腈纶纤维区分开来。其他纤维则呈现出不寻常的光学和形态特征，这强烈表明了它们的通用类别。红外光谱提供了有关共聚单体、添加到生产的染色位点的第三单体、溶剂残留物、染料和添加剂（例如阻燃材料）的信息。在对染料进行任何薄层色谱检查之前和之后，都应始终记录红外光谱，否则可归因于染料的峰将丢失，而这些峰在案件工作中可能是有价值的比较特征。
