02232nas a2200253   4500008004100000022001400041245011000055210006900165260006800234300001400302490000800316520130500324653001901629653001401648653001501662653001601677653003301693100002701726700002501753700002201778700002401800700002601824856012801850       2008                        eng d  a0021-899500aSynthesis, characterization, and gas permeability of aromatic polyimides containing pendant phenoxy group0 aSynthesis characterization and gas permeability of aromatic poly  a111 RIVER ST, HOBOKEN, NJ 07030 USAbJOHN WILEY & SONS INCcJUN  a3881-38890 v1083 a<p>A diamine containing a pendant phenoxy group, 1-phenoxy-2,4-diaminobenzene, was synthesized and condensed with different aromatic dianhydrides [4,4'-oxydiphthalic dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 3,3',4,4-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyltetracorboxylic dianhydride, and pyromellitic dianhydride] by one-step synthesis at a high temperature in m-cresol to obtain polyimides in high yields. Most of the polyimides exhibited good solvent solubility and could be readily dissolved in chloroform, sym-tetrachloroethane, N,N-dimethylformamide, NN-dimethylacetamide, and nitrobenzene. Their inherent viscosities were in the range of 0.33-1.16 dL/g. Wide-angle X-ray spectra revealed that these polymers were amorphous in nature. All these polyimides were thermally stable, having initial decomposition temperatures above 500 degrees C and glass-transition temperatures in the range of 248-281 degrees C. The gas permeability of 4,4'-oxydiphthalic dianhydride and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride based polyimides was investigated with pure gases: He, H-2, O-2, Ar, N-2, CH4, and CO2. A polyimide containing a -C(CF3)(2)- linkage showed a good combination of permeability and selectivity. (C) 2008 Wiley Periodicals, Inc.</p>10aGas permeation10amembranes10apolyimides10aselectivity10astructure-property relations1 aKothawade, Sandeep, S.1 aKulkarni, Mahesh, P.1 aKharul, Ulhas, K.1 aPatil, Anandrao, S.1 aVernekar, Subhash, P.  uhttps://library.ncl.res.in/content/synthesis-characterization-and-gas-permeability-aromatic-polyimides-containing-pendant-0