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JEOL Resources

Documentation in support of your JEOL product.

Rapid Analysis of p-Phenylenediamine Antioxidants in Rubber

p-Phenylenediamine (PPD) and derivative compounds are commonly used as antioxidants and antiozonants in black rubber. These compounds can cause sensitization leading to contact dermatitis in susceptible individuals. Detection of additives in polymers such as rubber can be important for clinical, forensic, and manufacturing applications. Here we show that DART can be used to identify the presence of these compounds within seconds without requiring any solvents or sample preparation.

Rapid Analysis of Glues, Cements, and Resins

DART™ can be used to analyze polymers, cements, resins, and glues by increasing the gas temperature to 450-550°C to induce pyrolysis. This has been applied to a variety of glues and resins, including epoxies, polyimide resins, PVD cement, and cyanoacrylates. Examples are shown here for cured and uncured epoxy resin and cyanoacrylate glues. The DART was operated with helium in positive-ion mode. The gas heater was set to 475°C. Resins were cured in an oven for several hours before analysis; some resin samples had been cured for longer periods of time (months or years). Exact masses and accurate isotopic abundances were used to assign elemental compositions for peaks in the mass spectra. Nominal-mass spectra were exported into a library database in NIST format to facilitate identification of unknowns.

Identification of Polymers

DART can be used to analyze polymers, cements, resins, and glues by increasing the gas temperature to 450-550° C to induce pyrolysis. This has been applied to a variety of polymers including Nylons, polypropylene and polyethylene, polyethylene terephthalate (PET), polyesters, poly(methyl methacrylate) (PMMA), polycarbonate, phenoxy resin, polystyrene, and cellulose. Examples are shown here for standard samples of Nylon, polystyrene, and cellulose.

Identification of Contamination on Welding Wires Using Cross-Platform Techniques in SEM and Mass Spec

A batch of contaminated welding wire received from a vendor by a customer was causing problems in a manufacturing process. Visual comparison of the clean and contaminated wire did not show any obvious differences, but the contamination was readily observed on backscatter electron images obtained with the JEOL IT300 scanning electron microscope.

Fiber analysis by thermal desorption/pyrolysis DART®

Analyzing fiber samples has always been difficult by DART®. The problem has been that there is no easy way to hold the fiber in the gas stream without losing it into the vacuum system. A fiber can be secured in the DART gas stream with forceps or other means, but if the DART gas is too hot, the fiber can break off and be lost into the mass spectrometer vacuum system through the atmospheric pressure interface. A thermal desorption/pyrolysis stage (The Biochromato, Inc. “ionRocket™”) designed for use with DART produces highly reproducible thermal desorption profiles that show outgassing, additives, and high-quality pyrolysis DART mass spectra for materials. Because fiber samples placed in the disposable copper sample “pots” are not positioned directly in the DART gas stream, a single fiber can be analyzed without risk of loss into the vacuum system.

Direct Analysis of Adhesives

DART can be used with a heated gas stream to rapidly pyrolyze and identify low-volatility materials such as adhesives and resins, directly on surfaces. Although these materials are not pure compounds, a library of DART mass spectra can be created and searched to identify materials, and exact mass measurements coupled with accurate isotopic abundances can be used to identify unknown components. Examples are shown here for cured and uncured epoxies and acrylate adhesives on metal and glass.

AccuTOF-DART analysis of motor oils

DART can characterize additives in lubricating oils directly without sample preparation. The additives generally produce a strong signal without interference from the base oil. However, complementary information about nonpolar components of the base oil can be obtained by O2 ─• attachment chemical ionization, a simple analysis that can be easily and rapidly carried out with changing any hardware on the AccuTOF-DART mass spectrometer system.

Analysis of duct tapes by thermal desorption and pyrolysis mass spectrometry and X-ray-fluorescence spectroscopy

The identification of pressure-sensitive tapes such as duct tape and electrical tape is an important forensic application. Here we show the application of thermal desorption and pyrolysis combined with Direct Analysis in Real Time (DART) mass spectrometry to distinguish between manufacturers and brands of duct tapes. X-ray fluorescence (XRF) provides complementary information about the atomic composition of the different tapes.

Analytical Instruments Documents

Other Resources

The following resources are available for the JEOL Analytical Instruments:

Media

Corona - Glow Discharge (DART Ion Source)

February 22, 2020
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