ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The effect of asymmetrical chlorine substitution in the mesogenic unit of poly(oxytetramethyleneoxycarbonyl-3-chloro-1,4-phenyleneoxyterephthaloyloxy-2-chloro-1,4-phenylenecarbonyl) (1) has been studied by means of differential scanning calorimetry, optical microscopy and X-ray diffraction. The polymer presents three-dimensional ordering, in spite of the substitution, and shows a transition to a nematic mesophase at 274°C and to the isotropic melt at 319°C. As for the unsubstituted polymer poly(oxytetramethyleneoxycarbonyl-1,4-phenyleneoxyterephthaloyloxy-1,4-phenylenecarbonyl), two different crystalline forms have been observed and some information about their structure has been obtained by Fourier-Transform Raman spectroscopy and 13C solid-state nuclear magnetic resonance. First results indicate that the most important structural differences between both polymorphs occur in the mesogenic unit.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1994.021950614
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