Synthesis of polymeric Schiff bases and their application in carbon dioxide adsorption

The emission of carbon dioxide (CO 2 ) is not only the primary cause of global warming but also results in severe environmental issues like an increase in Earth's average temperature. Herein, polymeric Schiff bases, OPVA-ED and OPVA-HMD, are synthesized via the condensation of partially oxidized polyviny1 alcohol (OPVA) with 1,2-ethylene diamine (ED) and 1,6-hexamethylene diamine (HMD), respectively, and their potential toward CO 2 adsorption is investigated. Fourier transform infrared (FTIR), 1 H nuclear magnetic resonance (NMR), and X-ray diffraction (XRD) are employed for the structural elucidation of these Schiff bases, and their physical properties are determined using thermogravimetric analysis (TGA), and gas adsorption experiments. The capture/release of CO 2 , using these Schiff bases as adsorbent, is assessed at 25°C. The results suggest that OPVA-ED is a more efficient adsorbent for CO 2 as compared to OPVA-HMD, as the capacity of CO 2 adsorption reaches up to 0.22 mmol/g and 0.18 mmol/g at 15 bars for OPVA-ED and OPVA-HMD, respectively.