Open Access

Structural analysis and the study of degradation properties are important in order to understand and improve performance characteristics of synthetic polymers and copolymers in many industrial applications. Polymers/copolymers are inherently difficult to analyze because of their high molecular weight and lack of volatility. Traditionally, various analytical techniques are used to characterize polymers/copolymers including physical testing (rheological testing), thermogravimetric analysis (TGA), electron microscopy, Fourier transform infrared (FTIR) spectroscopy, size-exclusion chromatography (SEC)/gel permeation chromatography (GPC), and mass spectrometry (MS). Often, time consuming sample preparation, including hydrolysis, dissolution, or derivatization is needed before analysis.

Gas chromatography with simultaneous flame-ionization detection (FID) and a nitrogen-phosphorus detection (NPD) as well as gas chromatography-mass spectrometry (GC/MS) has been used to characterize some long-chain primary alkyl amines and alkyl diamines after derivatization with trifluoroacetic anhydride (TFAA).

Die analytische Pyrolyse ist ein universelles Analysenverfahren für hochmolekulare organische Verbindungen. Unter Pyrolyse (griech.: Pyros = Feuer, Lyso = zersetzen) versteht man die chemische Umsetzung von Substanzen mittels Wärme. Bei der Pyrolyse von hochmolekularen Substanzen handelt es sich um eine thermische Zersetzung unter kontrollierten Bedingungen in niedermolekulare Verbindungen. Die niedermolekularen Pyrolyseprodukte werden dann den herkömmlichen Analysenverfahren unterworfen, welche Rückschlüsse auf chemische Zusammensetzung, Struktur und Eigenschaften der Ausgangsstoffe erlauben.

The analytical pyrolysis technique hyphenated to gas chromatography–mass spectrometry (GC–MS) has extended the range of possible tools for the characterization of synthetic polymers and copolymers. Pyrolysis involves thermal fragmentation of the analytical sample at temperatures of 500–1400 °C. In the presence of an inert gas, reproducible decomposition products characteristic for the original polymer or copolymer sample are formed. The pyrolysis products are chromatographically separated using a fused-silica capillary column and are subsequently identified by interpretation of the obtained mass spectra or by using mass spectra libraries. The analytical technique eliminates the need for pretreatment by performing analyses directly on the solid or liquid polymer sample. In this article, application examples of analytical pyrolysis hyphenated to GC–MS for the identification of different polymeric materials in the plastic and automotive industry, dentistry, and occupational safety are demonstrated. For the first time, results of identification of commercial light-curing dental filling material and a car wrapping foil by pyrolysis–GC–MS are presented.

Gas chromatography with flame-ionization detection (FID) and gas chromatography-mass spectrometry (GC/MS) with electron impact ionization (EI) and chemical ionization (PCI and NCI) were successfully used for separation and identification of commercially available longchain primary alkyl amines. The investigated compounds were used as corrosion inhibiting and antifouling agents in a water-steam circuit of energy systems in the power industry. Solidphase extraction (SPE) with octadecyl bonded silica (C18) sorbents followed by gas chromatography were used for quantification of the investigated Primene JM-T™ alkyl amines in boiler water, condensate and superheated steam samples from the power plant. Amine formulations from Kotamina group favor formation of protective layers on internal surfaces and keep them free from corrosion and scale. Alkyl amines contained in those formulations both render the environment alkaline and limit the corrosion impact of ionic and gaseous impurities by formation of protective layers. Moreover, alkyl amines limit scaling on heating surfaces of boilers and in turbine, ensuring failure-free operation. Application of alkyl amine formulation enhances heat exchange during boiling and condensation processes. Alkyl amines with branched structure are more thermally stable than linear alkyl amines, exhibit better adsorption and effectiveness of surface shielding. As a result, application of thermostable long-chain branched alkyl amines increases the efficiency of anti-corrosive protection. Moreover, the concentration of ammonia content in water and in steam was also considerably decreased.

Analytical pyrolysis technique hyphenated to gas chromatography/mass spectrometry (Py-GC/MS) has extended the range of possible tools for characterization of synthetic polymers/copolymers. Pyrolysis involves thermal fragmentation of the analytical sample at elevated temperature between 500 and 1400 °C. In the presence of an inert gas, reproducible decomposition products characteristic for the original polymer/copolymer sample are formed. The pyrolysis products are chromatographically separated by using a fused silica capillary column and subsequently identified by interpretation of the obtained mass spectra or by using mass spectra libraries. The analytical technique eliminate the need for pre-treatment by performing analyses directly on the solid or liquid polymer sample. In this paper, application examples of the analytical pyrolysis hyphenated to gas chromatography/mass spectrometry for the identification of different polymeric materials in the plastic and automotive industry, dentistry and occupational safety are demonstrated. For the first time results of identification of commercially light-curing dental filling material and a car wrapping foil by pyrolysis-GC/MS are presented.