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Updated: May 19, 2026
06:16
Monitoring the Effects of Illumination on the Structure of Conjugated Polymer Gels Using Neutron Scattering
Published on: December 21, 2017
Structural and mechanical alterations in polyoxymethylene: Insights from advanced irradiation technologies
Blanche Krieguer1, Fabien Girard1, Nathalie Dupuy1
1Aix Marseille Univ, Avignon Univ, CNRS, IRD, IMBE, Marseille, France.
Summary
This study shows that sterilizing polyoxymethylene (POM) with gamma, X-ray, or e-beam radiation increases radical concentration and degrades mechanical properties. Careful dose control is essential for effective sterilization without compromising material performance.
Area of Science:
- Materials Science
- Polymer Chemistry
- Radiation Physics
Background:
- Polyoxymethylene (POM) is a versatile engineering thermoplastic.
- Sterilization of medical devices often involves irradiation.
- Understanding irradiation effects on POM is crucial for material integrity.
Purpose of the Study:
- To investigate the structural and mechanical alterations in POM after gamma, X-ray, and e-beam sterilization.
- To correlate irradiation dose with material property changes.
- To determine optimal sterilization parameters for POM.
Main Methods:
- Electron Spin Resonance (ESR) for radical concentration analysis.
- Differential Scanning Calorimetry (DSC) for thermal property assessment.
- Tensile testing for mechanical property evaluation (yield strength, elongation at break).
- Fourier Transform Infrared (FTIR) spectroscopy for degradation analysis.
Main Results:
- Radical concentration increased with irradiation dose across all technologies.
- Mechanical properties (yield strength, elongation at break) decreased with increasing dose.
- Melting temperature remained stable, indicating crystalline phase preservation.
- FTIR confirmed oxidative degradation at higher irradiation doses.
Conclusions:
- Gamma, X-ray, and e-beam irradiation can sterilize POM effectively.
- Irradiation dose significantly impacts POM's radical concentration and mechanical properties.
- Controlled irradiation doses are necessary to maintain POM's performance and prevent degradation.
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