Screening of catalysts based on DFT and preparation of high transmittance PET films

High-transmittance polyester films are critical for advanced display technologies, yet the relationship between catalyst design and optical performance remains poorly understood. This work investigates seven metal-based catalysts and develops an economical and efficient composite catalyst accordingly. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies of these catalysts are calculated using density functional theory (DFT) method. Results demonstrate that catalysts with lower LUMO energy levels can significantly promote nucleophilic attack during polycondensation, consequently exhibiting superior catalytic efficiency. Subsequently, we prepare a composite catalyst composed of cobalt(II) acetate tetrahydrate and germanium(IV) oxide. By employing the composite catalyst, the synthesized PET films achieved promising transmittance of 91.43 % and luminosity of 92.82 %. This study provides a DFT-driven strategy for designing optical polyesters, offering a scalable approach for advanced display applications.