ISSN:
0887-624X
Keywords:
poly(amide-imide)s
;
trimellitic acid
;
smectic-A phase
;
phase transition
;
synchrotron radiation
;
bâttonet texture
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Polycondensation of α, ω-bis(-4-aminophenoxy) alkanes with trimellitic anhydride chloride (TMA-Cl) in m-cresol yielded a new class of poly(amideimide)s. Starting from the same diamine spacers poly(amideimides) with a more regular sequence of amide and imide groups were prepared by another synthetic method. All these poly(amide-imide)s are semi-crystalline and melt in the range of 250-300°C. They form a smectic-A phase over a narrow temperature range and suffer thermal degradation at the isotropization temperature (330-350°C). The smectic-A phase was characterized by optical microscopy (“batonnet texture”) and by synchrotron radiation measurements conducted at a heating rate of 20°C. Furthermore, it is demonstrated that slight variation of the chemical structure, such as methyl substituents or meta positions in the spacer prevent the formation of a LC phase. © 1995 John Wiley & Sons, Inc.
Additional Material:
11 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pola.1995.080331318
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