ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Two polyimides were prepared from 1,3-bis[4′-(4″-aminophenoxy)cumyl]benzene and 1,2:4,5-benzenetetracarboxylic dianhydride (PMDA) or 1,8:4,5-naphthalenetetracarboxylic dianhydride. A poly(amide-imide) was prepared from the same diamine and trimellitic anhydride. Furthermore, two polyimides were prepared from 1,4-bis-[4′-(4″-aminophenoxy)cumyl]benzene or a mixture of the 1,3- and 1,4-diamines. Moreover, one polyimide was synthesized from PMDA and 1,3-(4-aminocumyl)benzene. All polyimides were characterized by elemental analyses, optical microscopy, DSC and various X-ray measurements. Only the polyimide of PMDA and the 1,3-amine proved to be thermotropic. SAXS and WAXS measurements between 25 and 350°C, along with a fiber pattern suggest that this LC-polyimide forms a smectic-A phase in the melt and a disordered smectic-B phase in the solid state. Also most other polyimides formed a disordered smectic-B or a smectic-A glass in the solid state. However, the polyimide derived from 1,3-(4-aminocumyl)benzene crystallized in the form of a smectic-H phase with tilted mesogens. All results together underline the high potential of polyimides of form layer structures.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1997.021981011
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