ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
New aromatic-aliphatic semi-rigid homo- and copoly(imide-carbonate)s 7 containing the 4,4′-oxydiphthalimide ring system were prepared by melt polycondensation of N,N′-bis(6-hydroxyhexyl)-4,4′-oxydiphthalimide (4) and/or 6,6′-(4,4′-biphenyldiyldioxy)dihexanol (5) with hexamethylene diphenyl dicarbonate in the presence of zinc acetate, and their thermal and mesomorphic properties were evaluated. The assigned structures of the monomer and the polymers were identified by Fourier-transform infrared and 13C nuclear magnetic resonance spectroscopy and elemental analyses. Differential scanning calorimetry measurements, observation of the texture by means of a polarizing microscope equipped with a hot stage and powder X-ray analyses at various temperatures demonstrated that only the biphenyl moiety-rich polymers from nematic phases, but the 4,4′-oxydiphthalimide moiety-rich polymers exhibit no liquid-crystalline melts. It was suggested that the mesogenic character of the 4,4′-oxydiphthalimide ring system is low. The glass transition temperature steps decrease with the biphenyl moiety content. Thermogravimetry/differential thermal analysis (TG-DTA) measurements indicated that the polymers are thermostable up to 300°C in air.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1996.021970617
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