Synthesis and Characterization of Polyetheramides With Potential Capacity for CH4/CO2 Gases Mixture Separation

Block copolymers based on nylon-6 or nylon-12 and polyether in the PA/PE weight ratio 50/50 were synthetized through a two-step process. In the first step the nylon segment was chemically modified with adipic acid (end-capping). The second step involved the synthesis of the poly(etheramide) through bulk polycondensation of the modified nylon and polyether in the presence of Ti(OBu)₄ as a catalyst and irganox 1010 as antioxidant. The comonomers incorporation was studied by FTIR spectroscopy. The bands at 1725 cm^-1 and 1115 cm^-1 corresponding to C=O and C-O vibrations respectively, confirm the formation of the poly(ether-b-amide). The PA/PE ratio in the copolymers was determined by proton Nuclear Magnetic Resonance analysis (¹H-NMR) from the integration of CH₂CO and CH₂O signals, respectively.  The thermal behavior of the copolymers was studied by Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The block copolymers have potential applications in membranes for CO₂ from CH₄ separation.