Analytical Technique
Gas phase molecular fragmentation represents the standard approach for identifying organic finishes and plasticizers extracted from textile products during compliance testing. In this process, electron ionisation utilizes a high-energy electron beam to bombard vaporized analyte molecules, causing them to lose an electron and form unstable cations. These cations then fragment into a predictable pattern of smaller ions.
The resulting mass spectrum is compared against reference libraries to identify unknown chemicals.
Ionization Mechanism
Energy transfer occurs when vaporized analyte molecules cross the path of the seventy electron volt beam. This high-energy collision of electron ionisation systematically breaks specific covalent bonds within the extracted textile auxiliaries, such as flame retardants or softeners. The reproducibility of this process ensures that different instruments produce almost identical spectra for the same compound.
This high reproducibility is why laboratories rely on this method for standard screening procedures.
Spectral Fingerprint
Molecular identification is achieved by analyzing the unique fragmentation patterns produced by the high-energy impact. Each chemical substance yields a specific spectral fingerprint that corresponds to its molecular structure, which allows for the rapid identification of restricted compounds like phthalates or alkylphenols in garment extracts. Because the fragmentation is so extensive, the diagnostic peaks remain highly visible even when the original parent molecule is completely decomposed during the ionization process.
Application Limit
Thermal instability represents the primary boundary of this technique. Compounds must be vaporized without decomposing, which limits the method to volatile or semi-volatile substances extracted from the fabric.
