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Identification Characteristics of PLA Fibers: A New Generic Fiber Type

NCJ Number
218719
Author(s)
Heather A. Velez
Date Published
July 2003
Length
8 pages
Annotation
This study established a criterion for identification of PLA fiber (also called polylactide) in anticipation of this material presenting as evidence.
Abstract
The analysis indicates that solubility testing can be used as a rapid screening tool because the samples under examination dissolved in hexaflouroisopropanol (HFIP) in less than 5 seconds. PLA can be distinguished from other generic fiber types by using a routine fiber analysis protocol that includes solubility testing as well as Fourier transform infrared (FT-IR) spectra testing. The analysis involved examining five samples of PLA microscopically to obtain interference colors, birefringence by compensator and refractive index oils, melting point, solubility behavior, and FT-IR spectra. The five samples were provided by Cargill Dow LLC. The study was undertaken because the Federal Trade Commission recently awarded generic fiber status to PLA and it is anticipated that PLA will turn up as evidence in courtrooms around the country. As such, it is necessary to establish an identification protocol for identifying this material. Figures, tables, references