ORGS5-0355
Glycolysis of polyesterimides for sustainable recycling and upcycling of high value monomers
Topic
GS5. Graduate Student Oral Session V: Sustainable Polymers and Circular Materials
When and Where
Sep 28, 2026
16:12 - 16:24
Room 105
Session Chairs
Taehoo CHANG
Taejun EOM
Chae Bin KIM
Presenter(s)
Po Yi Lu (National Taiwan University)
Co-Author(s)
Abstract
The rapid advancement of microelectronic packaging and communication technologies demands functional polymers with outstanding thermal stability and low dielectric loss (Df). While high-performance resins like polyesterimides (PEIs) successfully fulfill these requirements, their robust imide structures pose critical environmental challenges for waste management. To achieve a sustainable recycling system without sacrificing the structural integrity of valuable functional groups, a highly efficient and selective chemical recycling system for PEIs via catalytic glycolysis is established. Using ethylene glycol (EG) as an environmentally friendly solvent, the reaction conditions for a bis[(3,4-dicarboxylic anhydride)phenyl] terephthalate (BCFE) and bis(4-aminophenyl) terephthalate (BPTP) based PEI system were systematically optimized. Complete depolymerization was achieved at 200 oC within 8 hours using 1 wt% zinc acetate (Zn(OAc)2) as a catalyst, selectively yielding bis(2-hydroxyethyl) terephthalate (BHET) and a rigid imide-ring-containing monomer, 5-hydroxy-2-(4-hydroxyphenyl)isoindoline-1,3-dione (HPID). Kinetic evaluations confirmed that the depolymerization process conforms to a first-order rate equation with an activation energy (Ea) of 145 kJ/mol. The isolated BHET exhibited exceptional chemical purity and was directly polycondensed to produce recycled PET (rPET) with a molecular weight and thermal stability comparable to commercial grades. Concurrently, the recovered HPID monomer completely retained its robust imide bonds and was successfully employed to synthesize high performance PEI displaying excellent thermal stability and low Df. This selective glycolysis protocol demonstrates excellent versatility across various aromatic, alicyclic, and bio-based PEI matrices, providing a promising and low-pollution pathway for high-value monomer recovery and upcycling.
