Investigation of biodegradable microparticle release and environmental accumulation in Poly(butylene succinate) degradation under UV and non-UV aging conditions

Abstract

This study investigates the release behavior of biodegradable microparticles and their environmental accumulation during the degradation of poly(butylene succinate) (PBS) through enzymatic hydrolysis and UV aging. By employing laser diffraction and image counting techniques, we monitored the real-time release of biodegradable microparticles during PBS degradation. The findings reveal that during enzymatic degradation, non-UV-aged PBS releases a significant number of microparticles, peaking at 4569 particles per 50 µL on the fifth day, with 97% of these particles subsequently degraded. In contrast, UV-aged PBS shows a markedly slower degradation rate. For samples pretreated with UV for 30 days, the number of released microparticles peaks at 1856 particles per 50 µL, and even after the complete disintegration of the primary material, approximately 52% of these microparticles remain undegraded. UV aging initially accelerated surface degradation due to photochemical reactions but ultimately reduced overall degradation efficiency by inducing crosslinking, resulting in persistent microparticle accumulation. Analytical techniques such as Scanning Electron Microscopy (SEM), Gel Permeation Chromatography (GPC), Nuclear Magnetic Resonance (¹HNMR ), and X-ray Photoelectron Spectroscopy (XPS) were used to analyze structural changes and degradation products, revealing surface chemical transformations and their impact on microparticle release. This research underscores the importance of comprehensive environmental assessments of biodegradable plastics, particularly focusing on the dynamic release of microparticles during degradation. The findings provide a critical scientific basis for developing safer biodegradable materials and contribute to effectively addressing plastic pollution issues.