The enhancement of the degradation temperature for the polyurethane–
zeolite mixed matrix membranes in comparison with
pure PU membrane could refer to two possible changes in the morphology
of MMM. The first and more acceptable is due to the good
interaction of the polymer chains with zeolite particles in MMM.
The second one is the appropriate distribution of the zeolite particles
in the polymer matrix. These two effects also have been concluded
by SEM, XRD and FTIR analyses.