Multi-amino functionalized triazine-based polymers as the catalyst for cycloaddition of CO2 to epoxides

Abstract

Designing efficient catalysts for CO₂ cycloaddition to reduce CO₂ emission is one of crucial for environmental issues technology. Herein, the multiple-amino functionalized triazine-based polymer (MAFTP) was prepared through the nucleophilic reaction of cyanuric chloride with melamine and ethylenediamine by a conventional heating method, which are favorable for CO₂ adsorption due to their nitrogen-rich structure. MAFTP was characterized entirely, the CO₂ adsorption capacity of MAFTP showed the CO₂ uptake performance with the values of 5.73 cm³ g⁻¹ at 273 K and 1 bar. MAFTP/KI catalyst exhibited efficient catalytic activity for CO₂ fixation to epoxides. 99 % propylene carbonate yield and 99 % selectivity were obtained under 120 °C, 2.0 MPa for 2.0 h without organic solvent. Additionally, the catalysts could be recycled easily from the products after reaction by centrifugation and then reused 5 times efficiently. Meanwhile, the catalytic activity of MAFTP/KI to other substituted epoxides was discussed. Moreover, DFT calculation was adopted to analyze the possible cycloaddition reaction mechanism. The MAFTP/KI system is a promising candidate for CO2 chemical fixation attributing to the low cost, abundant availability, easy separation and high catalytic activity for CO₂ chemical fixation.