Three Analytical Techniques of Double-Shot Pyrolyzer ® PY-2020D & iD Part 1: Evolved Gas Analysis

Significance of the Topic

This technical note presents an evolved gas analysis (EGA) approach using a multi-functional double-shot pyrolyzer. Thermal analysis of polymeric materials and additives is critical in quality control, material development and failure analysis. Direct measurement of evolved gases during controlled heating provides insights into volatile components and decomposition behaviour without cold spots or transfer losses.

Goals and Overview

This study aims to demonstrate the simplicity and effectiveness of double-shot pyrolysis EGA. It outlines the instrumentation configuration, heating protocol, and data interpretation, illustrating how the method distinguishes between volatilization and pyrolytic decomposition stages in a polymer model system (acrylonitrile butadiene rubber).

Methodology and Instrumentation

The analysis employs a double-shot pyrolyzer connected to a gas chromatograph via a deactivated metal capillary tube (EGA tube 0.15 mm id, 2.5 m length). Key parameters include

• Pyrolysis furnace temperature ramp from 50 to 600 °C at 20 °C/min
• Interface and injection port maintained at 320 °C
• GC oven held at a constant 300 °C to prevent cold spots
• Detector: flame ionization detector (FID) or mass spectrometer

Temperature control allows continuous gas evolution measurement, separating volatile desorption and polymer pyrolysis.

Main Results and Discussion

EGA of acrylonitrile butadiene rubber reveals two distinct peaks. A broad desorption peak between 120 and 300 °C corresponds to low-molecular-weight additives and volatiles. A second decomposition peak between 320 and 500 °C reflects main chain pyrolysis of the polymer matrix. These profiles enable selection of targeted thermal desorption (100–300 °C) and instant pyrolysis conditions (around 550 °C) for subsequent detailed GC analysis.

Benefits and Practical Application

Key advantages include

• Rapid identification of volatile and non-volatile fractions in a single run
• No cold-spot losses due to in-oven transfer line design
• Optimized temperature programs for selective analysis of targeted components
• Minimal sample preparation and direct coupling to detection systems

Applications span polymer formulation screening, additive quantification, contamination analysis and forensic investigations.

Future Trends and Possibilities

Integration with advanced detection methods such as high-resolution mass spectrometry and infrared spectroscopy will enhance compound identification. Automated data processing and machine learning could streamline interpretation of complex EGA curves. Development of standardized protocols will support regulatory compliance and cross-laboratory comparability.

Conclusion

Evolved gas analysis using a double-shot pyrolyzer offers a robust, direct and efficient approach for thermal profiling of polymers and additives. Its capacity to distinguish volatilization and pyrolysis phases supports targeted analytical workflows and informed decision making in research and quality control.

References

• PYA3-001E Correlation of Thermal Gravimetric Analysis and Evolved Gas Analysis using Double-Shot Pyrolyzer
• PYA1-004E Analysis of Antioxidants in Acrylonitrile Butadiene Rubber