Monitoring Epoxidized Soybean Oil Degradation Using Liquid Chromatography-Mass Spectrometry and In Silico Spectral...

Area of Science:

• Polymer Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Epoxidized soybean oil (ESO) is a common plasticizer and stabilizer in polyvinyl chloride (PVC).
• ESO degrades during PVC processing, forming complex chlorohydrin byproducts.
• Existing methods for ESO byproduct analysis are complex and indirect.

Purpose of the Study:

• To develop a comprehensive workflow for analyzing intact ESO byproducts during PVC thermal aging.
• To improve the characterization and understanding of ESO degradation mechanisms.
• To provide a high-resolution molecular timeline of ESO species and byproducts.

Main Methods:

• Development of a novel LC-MS/MS data acquisition and in silico spectral library identification workflow.
• Utilized detailed MS/MS fragmentation rules from synthesized standards and improved fragment ion intensity modeling.
• Employed retention time modeling to enhance identification confidence.
• Optimized extraction and reversed-phase separation for intact ESO byproduct analysis.

Main Results:

• Successfully generated a high-fidelity spectral library for rapid ESO byproduct identification.
• Identified over 400 ESO species and byproducts during PVC thermal aging.
• Provided a detailed timeline of ESO degradation with unprecedented molecular resolution.
• Demonstrated the capability to monitor individual ESO species during aging.

Conclusions:

• The developed LC-MS/MS workflow significantly advances the ability to detect and characterize ESO degradation in PVC.
• This approach offers a more direct and efficient method for analyzing complex ESO byproducts compared to previous techniques.
• The findings provide deeper insights into the molecular mechanisms of ESO degradation in PVC formulations.