Analysis of Residual Solvent in Polymers by GC/MS Double-shot Pyrolyzer (PY-2020D)

Importance of the Topic

Polymers produced for industrial and consumer applications often retain trace solvents from synthesis and processing. Monitoring these residual solvents is critical for ensuring product safety, performance consistency and regulatory compliance. Gas chromatography coupled with mass spectrometry (GC/MS) combined with a double-shot pyrolyzer offers a versatile platform to analyze both polymer matrices and trapped solvents without extensive sample preparation.

Objectives and Study Overview

This application demonstrates two complementary approaches to residual solvent analysis in polymers using a Frontier Lab PY-2020D double-shot pyrolyzer and Shimadzu GCMS-QP5050A. Part 1 focuses on quantitative determination of benzyl alcohol in an epoxy polymer film by liquid injection into the pyrolyzer. Part 2 employs evolved gas analysis (EGA) to examine how heat treatment affects solvent content in polyimide samples.

Methodology and Instrumentation

• Instrumentation Used
  • GCMS-QP5050A mass spectrometer
  • PY-2020D temperature-programmable double-shot pyrolyzer
• Part 1 Conditions
  • Liquid injection via 50 mm syringe needle (flash injection)
  • Ultra ALLOY+5 column (30 m×0.25 mm, df=0.25 µm)
  • Oven program: 40 °C (1 min) → 15 °C/min → 120 °C → 25 °C/min → 300 °C
  • Carrier gas ramp: 100 kPa → 150 kPa → 240 kPa
  • Injector 280 °C, split 1:100; EI, scan m/z 35–300
• Part 2 EGA Conditions
  • Pyrolysis ramp: 40 °C (2 min) → 20 °C/min → 700 °C
  • Ultra ALLOY-DTM-2.5N column (2.5 m×0.15 mm)
  • Oven at 300 °C, carrier gas 20 kPa, split 1:50; EI, scan m/z 35–500

Main Results and Discussion

• Quantification of Benzyl Alcohol
  • Linear calibration over 1–10 µg injections (R²=0.99998)
  • Polymer sample heated at 230 °C shows peak tailing due to gradual solvent release
  • Five replicates yielded 3.5–4.2 µg/mg with CV <6 %
• EGA of Polyimide
  • Low-temperature treated sample exhibits two TIC peaks at 200–400 °C (solvent evolution) and 600–700 °C (polymer decomposition)
  • High-temperature treated sample lacks the low-temperature peak, indicating effective solvent removal

Benefits and Practical Applications

• Direct injection into pyrolyzer minimizes sample prep and avoids solvent exchange steps
• Simultaneous analysis of polymer backbone and residual solvents accelerates QA/QC workflows
• Reproducible quantification supports formulation development and regulatory reporting

Future Trends and Opportunities

• Integration with high-resolution MS for enhanced compound identification
• Automated sample introduction for higher throughput
• Advanced multi-shot pyrolysis protocols to differentiate additives, monomers and degradation products
• Real-time monitoring of solvent evolution during polymer processing

Conclusion

The double-shot pyrolyzer coupled with GC/MS provides an efficient, sensitive and reproducible approach for residual solvent quantification and thermal profiling in polymers. These methods facilitate comprehensive material characterization and support quality control in polymer manufacturing.

References

• No external literature references cited in this application note