NCJ Number
183388
Journal
Journal of Forensic Sciences Volume: 44 Issue: 2 Dated: March 1999 Pages: 275-282
Date Published
March 1999
Length
8 pages
Annotation
This article describes a new method for fiber comparison using polarized infrared microspectroscopy.
Abstract
Polarized infrared (IR) microspectrometry was used to measure the changes in infrared absorption resulting from the molecular orientation of single textile fibers. The model chosen for preliminary single-fiber stretching experiments was acrylic (polyacrylonitrile) fibers. Dichroic ratios were determined from single experimental fibers subjected to incremental elongation from an unstretched to a stretched condition. Similar measurements were made on commercial fibers of the same polymer with known draw ratios. These infrared spectroscopic measurements provided a direct means for comparing fibers drawn under production conditions with single fibers stretched in controlled experiments. The dichroic ratio data are indicative of the molecular orientation that occurs when fibers are drawn in the manufacturing process. Dichroic ratio data of commercial fibers can be used to monitor textile fiber quality and to compare fiber evidence in forensic investigations. Tables, figures, references