Gas chromatography (GC) is a common chromatography method that relies on differences in partitioning behavior between a flowing mobile phase and a stationary phase in order to separate volatile or semi-volatile organic or inorganic compounds.
The GC technique is used for a large variety of analyses including:
- identification and quantification of residual monomers or solvents in resins and coatings
- analysis of volatile components or impurities
- verification of additive levels in polymer formulations and finished products
- quantification of trace contaminants
- analysis of gas mixtures
- on-line or at-line monitoring of reactions.
A number of specialized detectors are available, including FID (flame ionization), AED (atomic emission), FPD (flame photometric) and TCD (thermal conductivity). In addition, mass spectrometry (MS) is available, allowing great flexibility in both qualitative and quantitative evaluation of materials containing species that are difficult to separate.
Arkema Analytical Solutions also offers several specialized gas chromatography services:
Pyrolysis GC and Pyrolysis GC/MS analysis
Pyrolysis is used to break down molecules thermally to compounds that are volatile enough to be analyzed using gas chromatography. The degradation products of the original molecule create a pattern of peaks that is characteristic for the particular material. When coupled with mass spectrometry, pyrolysis is an invaluable tool for identifying unknown polymer materials and copolymer composition. Pyrolysis is also used to deformulate polymers and to identify thermal decomposition products of both polymers and non-polymers.
Headspace GC, Headspace GC/MS analysis
Headspace analysis allows study of the components present in the gas phase above a sample in a chromatography vial. Headspace GC is used for the analysis of volatiles and semi-volatile organics in solid, liquid and gas samples. Arkema Analytical Solutions uses multiple stage headspace analysis to simplify the quantification process.