PISOX Copolyesters-Bio- and CO₂-Based Marine-Degradable High-Performance Polyesters.

Area of Science:

• Polymer Chemistry
• Materials Science
• Sustainable Chemistry

Background:

• Isosorbide and oxalate esters are renewable polymer building blocks.
• Low reactivity of isosorbide's secondary hydroxyl groups hinders high-molecular-weight polymer synthesis.
• Existing polyesters often lack desired material or environmental properties.

Purpose of the Study:

• To develop a scalable method for producing high-molecular-weight isosorbide-based polyoxalates (PISOX).
• To investigate the material properties and biodegradability of the synthesized PISOX.
• To explore PISOX as a sustainable alternative to conventional plastics.

Main Methods:

• Polymerization of diaryl oxalates with isosorbide without a catalyst.
• Characterization of PISOX thermal, mechanical, and barrier properties.
• Assessment of PISOX biodegradability under home-composting and aqueous conditions.

Main Results:

• High-molecular-weight PISOX synthesized rapidly (<5 h) and scalably without catalysts.
• PISOX exhibits excellent thermal stability (Tg 167 °C), mechanical strength, and oxygen barrier properties (35x better than PLA).
• PISOX decomposes into CO2 and biomass within months in soil and hydrolyzes in water within a year.

Conclusions:

• Catalyst-free polymerization of isosorbide and diaryl oxalates yields high-performance PISOX.
• PISOX offers a unique combination of desirable material properties and rapid biodegradability.
• PISOX holds significant potential for diverse applications, reducing environmental impact.