Carbon dioxide (CO2) absorption behavior of mixed matrix polymer composites containing a flexible coordination polymer

► CO2 adsorption occurs in flexible Ni(Bpy)(DBM)2 dispersed in polymer matrices. ► IR spectral bands can distinguish CO2 adsorption sites in the mixed matrix. ► Threshold pressure for CO2 adsorption is not affected by polymer host matrices. ► No evidence of CO2 adsorption in envelopment pockets observed in the IR spectra.