ISSN:
0021-8995
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
,
Physik
Notizen:
A series of bis(benzylterephthaloyl-p-oxybenzoyl)esters (mesogen I) and bis(p-carboxybenzoyl-p-oxybenzoyl)esters (mesogen II) of several different polymeric glycols was prepared, and their thermotropic liquid crystalline behavior was studied by differential scanning calorimetry and by visual observation on the hot stage of a polarizing microscope. The polymeric glycols used were poly(ethylene oxide) (A), poly(tetramethylene oxide) (B), polybutadiene (C), and the hydrogenated polybutadiene (D) glycols, with molecular weights between 650 and 6000. With one exception, the benzyl ester derivations were not thermotropic, but the corresponding carboxylic acid derivatives were, and the related model compound, the bis(p-carboxybenzoyl-p-oxybenzoyl)ester of 1,12-dodecanediol, was also found to be liquid crystalline. The nature of the mesophases formed by the diacids derived from the macroglycol derivatives could not be clearly identified by their optical textures. Several of the diacid derivatives formed elastomeric films, even though they were still of low molecular weight, presumably because of chain extension by dimerization and association of the terminal mesogenic groups.
Zusätzliches Material:
2 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/app.1984.070290209
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