Multi-Sample UV Irradiator - Part 1 Development -

Significance of the Topic

The accelerated evaluation of polymer photo-thermal and oxidative degradation is essential in materials science and quality control. Rapid screening of multiple samples under controlled UV and temperature conditions allows researchers and industrial laboratories to predict service life, optimize formulations, and ensure regulatory compliance.

Objectives and Study Overview

This technical note describes the development of a Multi-Sample UV Irradiator (UV-1048E) enabling simultaneous irradiation of up to 18 samples. The goal is to expand upon single-sample UV/Py-GC/MS methods by increasing throughput while maintaining precise control of irradiation parameters.

Methodology

Samples are loaded into a rotating holder featuring two concentric circles (6 inner, 12 outer positions) tilted toward the fiber bundle by 7°. A Xe–Hg arc lamp delivers UV light via a 525-fiber optical bundle, irradiating all cups uniformly. Key parameters include:

• Holder temperature: 40–80 °C in 1 °C increments
• Rotation speed: 0–8 rpm
• Distance from fiber tip to sample: 25–160 mm
• Exposure time and radiation intensity: user-defined

Instrumentation Used

• Multi-Sample UV Irradiator (UV-1048E)
• Micro-UV Irradiator (UV-1047Xe)
• Xe–Hg arc lamp light source
• Optical fiber bundle (525 fibers, 0.2 mm diameter each)

Key Results and Discussion

The multi-sample design achieved uniform UV exposure across all positions, with efficient irradiation confirmed by comparative degradation markers. Rotation and tilt geometry optimized light distribution. Temperature control ensured consistent thermal contribution to oxidative pathways. Throughput increased 18-fold versus single-sample setups without compromising reproducibility.

The flexibility in adjusting exposure time, temperature, and distance supports diverse polymer formulations and experimental protocols. Sample degradation profiles obtained align closely with existing single-sample data, validating the new system’s analytical reliability.

Benefits and Practical Applications

• High-throughput screening for polymer stability studies
• Accelerated weathering tests in R&D and QA/QC
• Flexibility to simulate varied real-world UV/thermal conditions
• Integration with GC/MS for on-line analysis of degradation products

Future Trends and Opportunities

Advances may include automation of sample loading, integration with real-time spectral monitoring, and expansion to other degradation stimuli (e.g., humidity, ozone). Miniaturized fiber optics and enhanced lamp sources could further improve uniformity and energy efficiency. Coupling with machine learning for predictive degradation modeling represents another promising direction.

Conclusion

The Multi-Sample UV Irradiator (UV-1048E) offers a robust platform for simultaneous UV-induced aging of multiple polymer samples under controlled conditions. Its high throughput and adaptable parameters make it a valuable tool for both academic research and industrial quality assessment.

References

1. C. Watanabe et al., Polymer Degradation and Stability, 94 (2009) 1467–1472; T. Yuzawa et al., Polymer Degradation and Stability, 96 (2011) 91–96.
2. K. Matsui et al., Polymer Testing, 56 (2016) 54–57.