4. Conclusion
FTIR spectra show that phase separation of hard and soft
segments in polyurethane was increased by changing of chain extender BDO to a mixture of the BDO/BDA. Because of interaction
between amine and carbonyl functional groups, the change of
chain extender type causes the increase in polymer crystallinity
of polyurethane, which is shown in XRD patterns. Increasing of
hard and soft segments phase separation and polyurethane crystallinity
lead to improve gas separation properties such as selectivity
and permeability. Zeolites (4Å and ZSM-5) addition to polyurethane
improved Hydrocarbons separation properties. Separation
selectivity was increased by adding more ZSM-5 to the polymer,
while it was decreased by increasing Zeolite 4Å. Maximum
selectivity was obtained by setting C2/C1 to 2.210 and also C3/C1
to 3.634 for PU2-ZSM-5-20% sample.