Analysis Using UV/Py -GC/MS System

Importance of the Topic

Accelerated weather-induced degradation testing is critical for assessing long-term performance of polymeric materials used in automotive, construction and electrical industries. Conventional methods relying on outdoor exposure or weather meters can require months to yield results. The combination of micro-UV irradiation with pyrolysis GC/MS offers rapid insight into photo-thermal-oxidative degradation pathways and volatile product formation, enabling quality control and material optimization in a fraction of the time.

Study Objectives and Overview

The study aimed to demonstrate a UV/Py-GC/MS system integrating a micro-UV irradiator and GC/MS for fast detection of degradation products in ABS resin containing a brominated flame retardant (DBDE). Key goals included identifying volatile and brominated species generated under controlled UV exposure and correlating product formation with irradiation time.

Methodology and Instrumentation

Experiments employed a double-shot pyrolyzer fitted with a xenon arc lamp (280–450 nm) delivering UV light via fiber optics. ABS samples with 1 % DBDE in THF were dried in eco cups and irradiated at 60 °C in air for up to 30 minutes. Volatile products were cryo-trapped at the GC inlet using liquid nitrogen and analyzed by TD-GC/MS. Residual polymers were characterized by EGA-MS and Py-GC/MS.

• Instrument configuration: PY-2020iD pyrolyzer, UV-1047Xe irradiator, GCMS-QP2010 Plus
• UV wavelength range: 280–450 nm (optional 300–400 nm filter)
• Atmosphere: air
• Irradiation temperature: 60 °C
• Sample size: 10–50 µg
• GC conditions: UA-DTM column (2.5 m×0.15 mm), oven to 300 °C, split 1:50

Main Results and Discussion

EGA thermograms before and after 30-minute UV exposure revealed increased evolution of low-molecular-weight products including brominated fragments. TD-GC/MS identified bromomethane and 1-bromo-3-propanol as primary halogenated volatiles. Additional oxygenated compounds such as acetaldehyde, methyl formate, acetic acid and tert-butanol emerged after UV treatment. A linear relationship was observed between UV irradiation time and the peak areas of brominated products, confirming proportional degradation kinetics.

Benefits and Practical Applications

The UV/Py-GC/MS system enables rapid screening of polymer degradation, replacement of lengthy outdoor tests, and detailed mechanistic insight into photo-thermal-oxidative pathways. It supports formulation development, failure analysis and regulatory compliance by identifying harmful volatiles and flame retardant breakdown products early in the degradation process.

Future Trends and Potential Applications

Further integration of tunable UV sources and advanced pyrolysis modes may broaden degradation studies to diverse polymer types and complex formulations. Automated data analysis and coupling with high-resolution MS can enhance identification of trace products. The methodology holds promise for accelerated lifetime prediction, environmental impact assessment and novel polymer stabilizer screening.

Conclusion

The combined micro-UV irradiation and GC/MS approach effectively accelerated the evaluation of polymeric material degradation, providing rapid detection of volatile and brominated products and quantifiable degradation kinetics. This technique offers a powerful tool for materials research, quality control and regulatory testing.