Fourier transform Raman spectroscopic studies of the curing of cyanoacrylate glue

The spontaneous polymerization of ethyl 2-cyanoacrylate ('superglue') in a sealed glass tube was studied using Fourier transform Raman spectroscopy with 1064 nm excitation. The spectra of the monomer and the polymer were characterized and the polymerization process was monitored qualitatively over a time interval of 92 days. Even after this time lapse from initiation, the reaction had not proceeded to completion and 15% monomer remained in the polymerized specimen, based on nu(C=C) band intensity depletion and on the evolution of the nu(CN) feature; the latter becomes asymmetric as the reaction proceeds owing to the appearance of the polymeric v(CN) stretch at 2247 cm(-1) and the diminution in intensity of the monomer band at 2239 cm(-1). The results of this work are of relevance to the non-destructive Raman spectroscopic analysis of cyanoacrylate-fumed latent fingerprints at forensic crime scenes. Copyright (C) 2004 John Wiley Sons, Ltd.