ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Copolymers derived from polyepichlorohydrin (PECH), bearing pendant mesogenic units are obtained by chemical modification of atactic samples of PECH with sodium 4-cyano-4′-biphenoxide. Rate and yield of substitution are strongly dependent on the molecular weight of the used PECH. A substantial rise (ΔT ∼ 110°C) of glass transition temperature with the percentage of incorporated cyanobiphenyl groups is observed. Copolymers with an amount of substitution higher than 60% present thermotropic liquid-crystalline behaviour and form nematic phases. Chemical modification of PECH offers a simple method for the synthesis of new liquid-crystalline polyethers whose transition temperatures can be adjusted by varying the amount of substitution.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1992.021930316
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