Assessment of commercial poly(e-caprolactone) as a renewable candidate for carbon capture and utilization

Poly(e-caprolactone) (PCL) is a cheap and sustainable polymer with long-term degradation (3–4 years)and low temperature transition (Tm =60 C). We report on the investigation of PCL as a valid greencandidate for Carbon Capture and Utilization (CCU). Studies were carried out by two complementarytools: a Sievert-type volumetric apparatus, to thoroughly analyse the CO2 adsorption/desorption processinside the polymer, and Nuclear Magnetic Resonance (NMR) spectroscopy for a deeper study of themolecular dynamics and confinement effects through 13C – pulsedfield gradient (PFG) method (selfdiffusionmeasurements), relaxation times (T1) and spectral analysis. The morphology of the solid-statePCL was also investigated by Scanning Electron Microscopy (SEM). The effects of both the physical stateand the adsorption process conditions on the PCL's CO2 sorption capabilities were investigated as well asthose concerning the cyclic life and the regeneration process. Wefind that two kind of adsorption sitesare present in PCL matrix. Furthermore, PCL show a remarkable and complete thermoreversibility of theCO2 adsorption process, a key condition in view of possible applications in thisfield.