Analytical Instrument Documents

The characteristics of polymeric materials vary depending on the additives. Consequently, a variety of additives can be added into the raw polymer resin in order to achieve the required characteristics for the product. PY/GC/MS is often used as an analytical method for the analysis of polymeric materials. However, PY/GC/MS is often insufficient for the chromatographic separation of additives and thermal decomposition products from the polymer. As a result, it is often difficult to assign compound identities. On the other hand, comprehensive two-dimensional gas chromatography/high resolution time-of-flight mass spectrometry (GCxGC/HRTOFMS) is a well-known technique that provides high chromatographic separation by using two different polarity GC columns. Additionally, when this technique is used with high resolution mass measurements, it can be a powerful tool for estimating elemental compositions of analytes found within a complex mixture. In this application note, the additives were identified within a commercially available molded polymer by using pyrolysis (PY)/GCxGC/HRTOFMS.

The high boiling point compounds cholesterol and Irganox® 1010, an anti-oxidant additive for polymers, were analyzed by GC/MS. The analyses were performed using electron ionization (EI) and field ionization (FI), which is a soft ionization method, to show the difference in mass spectral patterns that result from these two ionization techniques.

Advances in mass spectrometry are enabling analysis of micro samples and unknown components that were not observable before. As the volume of information acquired from mass spectrometry increases, researchers are calling for simple techniques to analyze numerous components observed, and as a result, there is a rise in demand for comprehensive analytical techniques including multiple classification analysis. In this work, we will introduce a new technique for non-target analysis, which combines comprehensive analysis using high resolution GC-TOFMS and unknown component analysis using soft ionization.

Compounds which are generated upon heating polymer materials include monomers, additives and fragments characteristic of the polymer materials. Low molecular weight compounds generated by pyrolysis and/or locally desorption are observed. The relationship between the behavior of evolved gas compounds and the heating temperature is important for understanding the chemical characteristics of polymer materials. A gas chromatograph (GC) - mass spectrometer (MS) with thermogravimetric / differential thermal analyzer (TG/DTA) or pyrolyzer (Py) is generally used to identify the thermally evolved gas compounds from polymer materials. However, GC with a low-resolution MS such as quadrupole MS (QMS) may have difficulty monitoring low molecular-weight compounds generated by heating, since the GC is not used to provide chromatographic separation and QMS has poor mass spectrometric separation in the low mass region. (For example, N2+·, CO+· and C2H4+· are detected as the same signal of nominal mass m/z 28.) We report the use of Py - GC - high resolution time-of-flight MS (HRTOFMS) for monitoring the low-molecular weight compounds generated upon heating the polymer materials. This report focuses on the generation of low molecular weight compounds near m/z 18, 28, and 4.

This report shows the analyses of the phenolic polymer antioxidants shown in Fig. 1. These samples were analyzed by using the AccuTOF-GCV with both direct insertion probe(DIP)electron ionization (EI) and field desorption (FD).

Three polydimethylsiloxane compounds: octamethylcyclotetrasiloxane (sample 1), decamethylcyclopentasiloxane (sample 2) and octa(dimethylsiloxy)silsesquioxane (sample 3), were analyzed using a GC/TOFMS. The first two samples are relatively small molecules with molecular weights of 296 and 370, respectively, so they were introduced into the system through the mass reference sample inlet (reservoir). Sample 3 is a much bigger molecule with a molecular weight of 1,016 that could not be introduced through the reservoir. As a result, this sample was introduced by injecting it into the GC.

A UV and visible light curing adhesive is a liquid composed of monomer, oligomer, initiator and additives. These adhesives cure over a short period of time when they are exposed to the appropriate light. In this report, a photo polymerization initiator found in a UV light curing adhesive was analyzed by electron ionization (EI) and field ionization (FI) using the high resolution and high mass accuracy capabilities of the AccuTOF-GC.

Ionic liquids are liquids that are predominantly comprised of ions and ion-pairs. More recently, this term has generally referred to salts that are in a liquid state at room temperature. Ionic liquids are electrically conductive and have an extremely low vapor pressure. Additionally, many of these liquids have low combustibility and excellent thermal stability. As a result of these properties, ionic liquids are expected to find many applications as functional materials.

A commercially available polyoxypropylene (PO) - polyoxyethylene (EO) block copolymer was analyzed by using the JMS-T100GC “AccuTOF GC” field desorption (FD) method. A group-type analysis was performed on the resulting mass spectrum.

Field desorption (FD) is an ionization method that utilizes electron tunneling in a high electric field near the emitter surface or whisker tip. Sample is applied directly on the emitter, and is then heated by applying an electric current through the emitter for desorption and ionization. FD has been used to analyze nonvolatile compounds, polymers, etc. as a soft ionization method that produces intact molecular ions with very few fragment ions in most cases. In this work, we used FD to analyze several near infrared (NIR) photosensitive dyes that were designed as photoinitiators for the polymerization of functional polymers.

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