2014-Effect of isomerism on molecular packing and gas transport properties of poly(benzoxazole-co-imide)s
writer：Yongbing Zhuang，Jong Geun Seong，Yu Seong Do，Hye Jin Jo，Moon Joo Lee，Gang Wang, Michael D. Guiver*, Young Moo Lee*
keywords：氣體分離膜
source：期刊
specific source：Macromolecules
Issue time：2014年
A facile approach to synthesize poly(benzoxazole-co-imide)s without thermal rearrangement at high temperature is proposed. Poly(benzoxazole-co-imide)s
with improved mechanical and solution-processable properties were
prepared through polycondensation of 4,4′-(hexafluoroisopropylidene)
diphthalic anhydride (6FDA) with three synthesized novel
benzoxazole-containing diamines and a commercial diamine. These
poly(benzoxazole-co-imide)s had high tensile strengths of
110.3–122.0 MPa and good elongation at break of 11.9–26.3%, good thermal
stability and high glass transition temperatures (Tgs)
of up 306 °C. The effect of chain isomerism on molecular packing and
physical and gas transport properties of the poly(benzoxazole-co-imide)s was investigated. The para-connecting isomers exhibited higher molecular weights (Mws), better mechanical properties, higher Tgs, higher chain packing order and better overall performance for CO2/CH4 and CO2/N2 separations as compared to the corresponding meta-connecting
ones. This study guides molecular architecture to improve particular
membrane separation performance by introducing either para- or meta-connections into polymeric main chains.