Structural and mechanical alterations in polyoxymethylene: Insights from advanced irradiation technologies

The study investigates structural and mechanical changes in polyoxymethylene (POM) resulting from gamma, X-ray, and e-beam irradiation used for sterilization. Techniques such as Electron Spin Resonance (ESR), Differential Scanning Calorimetry (DSC), and tensile testing were employed to examine irradiation-induced effects. As the irradiation dose increases, the radical concentration consistently rises for all radiation technologies, although slight variations are observed depending on the specific irradiation technology. Mechanical properties, including yield strength and elongation at break, progressively decline with increasing dose, whereas the melting temperature remains nearly constant, indicating the preservation of the crystalline phase. FTIR analysis confirms the onset of oxidative degradation at higher doses. Overall, the findings demonstrate that irradiation can effectively sterilize POM, provided that the dose is carefully controlled to prevent detrimental alterations to the material's performance.