The Polymer Society of Korea

정지석 (부산대학교)

현규 (부산대학교)

Polyethylene terephthalate (PET) is a widely used thermoplastic, but its low recycling rate and property degradation limit long-term use. To address this, we enhanced the processability, viscoelasticity, and mechanical properties of degraded PET by introducing dynamic network bonding. Using an eco-friendly, catalyst-free method, PET was upcycled into a vitrimer via torque rheometer with a tertiary amine and diepoxy. Rheological tests analyzed viscoelastic and thermal properties depending on crosslinking content. To further improve performance, we examined the effects of hydrophilic (silica 90) and hydrophobic (silica R202) fillers. While fillers enhance material properties, they may restrict chain mobility and hinder bond exchange. We evaluated the rheological, mechanical, thermal, and self-healing properties of vitrimer composites to understand filler influence. The results provide insights for designing high-performance PET vitrimers and advancing sustainable recycling strategies.