ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Four series of new poly(β-aminoester)s based on different mesogenic units and amino spacers were prepared and their properties examined. The polymers were obtained by a Michael-type polyaddition reaction of the diamines piperazine (5a), 2-methylpiperazine (5b), N,N′-dimethylhexamethylenediamine (5c), and 4,4′-trimethylenedipiperidine (5d) to diacrylates containing the anisotropic group, trans-4,4′-vinylenedi-p-phenylene diacrylate (1), 4-(4-acryloyloxybenzylideneamino)phenyl acrylate (2), 4,4′-diphenylylene diacrylate (3), and 4,4′-azoxydi-p-phenylene diacrylate (4). The mesophase behaviour of the resulting polymers 6-9 was strongly influenced by the nature of both the anisotropic and spacer groups. The 4,4′-azoxydi-p-phenylene unit appeared to be the most efficient in promoting liquid crystal properties, whereas no mesophases could be observed in polymers incorporating the 4,4′-biphenylylene unit. Doping of poly(β-aminoester)s, based on 4,4′-azoxydi-p-phenylene units, with a low-molar-mass cholesterogen allowed to obtain cholesteric structures extending over wide ranges of temperature. The molecular weight of the polymers was found to play a role in determining thermotropic mesomorphism by affecting the melting temperature of the polymer. In this context, some non-macromolecular model compounds were analyzed in respect of their thermal behaviour.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1985.021860508
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