Analysis of Mending Tape

Significance of the Topic

The analysis of composite materials such as mending tape requires selective identification of each polymer component. A two-step thermal decomposition strategy enables separation of acrylic adhesive and polypropylene base polymer, improving accuracy in polymer analysis and quality control.

Objectives and Study Overview

This study aims to develop a robust pyrolysis GC-MS approach for analyzing mending tape by:

• Applying an initial thermal decomposition step to selectively remove acrylic adhesive
• Generating a clear chromatogram of polypropylene through a subsequent higher temperature pyrolysis

Methodology

Samples of mending tape were subjected to a two-stage pyrolysis sequence. The first stage at 350 °C targets the decomposition of the acrylic adhesive while preserving the polypropylene layer. In the second stage, the temperature is raised to 450 °C to fully pyrolyze the polypropylene and obtain its characteristic thermal decomposition profile.

Instrumentation Used

The analysis was conducted on a GCMS system equipped with a pyrolyzer:

• Pyrolyzer GCMS-QP5000 PYR-4A
• DB-1 capillary column (0.25 mm × 30 m, film thickness 0.25 µm)
• Temperature program: 50 °C (1 min) to 300 °C at 10 °C/min
• Injection temperature 300 °C; interface temperature 320 °C
• Carrier gas pressure programming from 100 kPa to 250 kPa
• Split ratio 1:10

Main Results and Discussion

The initial pyrolysis at 350 °C produced a chromatogram dominated by acrylic adhesive fragments, with minimal polypropylene signals. The subsequent 350–450 °C pyrolysis yielded a clean polypropylene chromatogram, highlighting distinct thermal decomposition products. Comparison of total ion chromatograms demonstrated effective separation between adhesive and base polymer.

Benefits and Practical Applications of the Method

This selective pyrolysis GC-MS technique offers:

• Improved identification of individual polymer layers in composite materials
• Reduced interferences from mixed polymer signals
• Enhanced workflow efficiency for quality control in adhesive and polymer manufacturing

Future Trends and Potential Applications

Advancements may include coupling pyrolysis GC-MS with high-resolution mass spectrometry and chemometric data analysis for more detailed polymer characterization. The method could be extended to other multi-component materials such as laminated plastics, coatings, and composite films.

Conclusion

A two-stage thermal decomposition approach in pyrolysis GC-MS successfully isolates and analyzes acrylic adhesive and polypropylene in mending tape. This method enhances selectivity and clarity in polymer analysis, making it valuable for research and industrial quality control.

References

• Application News No. M174