ISSN:
0887-624X
Keywords:
bisaryloxy-bisimido-bisphthalonitriles
;
thermally-polymerizable monomers
;
4-(3′-aminophenoxy)phthalonitrile
;
tetracarboxylic dianhydrides
;
1H-NMR
;
13C-NMR
;
mass spectroscopy
;
structural assignment
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A proton-NMR study of the condensation reaction (step 1) of 4-(3′-aminophenoxy)phthalonitrile (4-3′APPN) (I) in an aprotic solvent with various aromatic dianhydrides demonstrated the formation of the corresponding bisamic acid within 5-10 min. There was no effect of the electron affinity of the used aromatic dianhydrides on the time of the condensation reaction and also no charge-transfer complex formation was indicated. Proton-NMR study of the synthesized bisaryloxy-bisimido-bisphthalonitriles at 250.1 MHz has revealed general findings for their NMR characterization. The coupling constant (J) value for the ortho-coupled protons of the phthalonitrile ring of the 4-3′-APPN portion is 8.8 ± 0.05 Hz and that for the ortho-coupled protons of the aminophenoxy ring of 4-3′-APPN is 8.1 ± 0.05 Hz. The coupling constant (J) values for ortho-coupled protons of the dianhydride portion range from 8.1 to 7.5 Hz. Various thermally polymerizable bisaryloxybisimido-bisphthalonitriles (BBBP) (X, XI, XII, and XIII) containing dimethylsilane, hexafluoroisopropylidene, ether, and keto groups, suitable for the development of thermooxidative stable, void-free composites, were synthesized by two methods. In method 1,4-3′-APPN (I) in N,N-dimethylacetamide (DMAC) was condensed (step 1) with bis(3,4-dicarboxyphenyl)dimethylsilane dianhydride (SIDA) (II), 4, 4′-hexafluoroisopropylidenediphthalic anhydride (6FDA) (III), bis(3,4-dicarboxyphenyl)ether dianhydride (ODPA) (IV), and 3,4,3′,4′-benzophenonetetracarboxylic dianhydride (BTDA) (V), respectively, to give the corresponding bisamic acids. Thermal cyclodehydration of the intermediate bisamic acid at 160°C gave the bisphthalonitriles. In method 2, the second step of thermal cyclodehydration was performed in situ in refluxing toluene. The characterization of the synthesized bisaryloxy-bisimido-bisphthalonitriles (BBBP) was performed using FT-IR, 1H-NMR, 13C-NMR, mass spectroscopy, and elemental analysis. A preliminary study indicated that thermal-polymerization of these bisphthalonitriles (BBBP) gave tough, thermosetting polymers, useful for high-temperature applications. © 1993 John Wiley & Sons, Inc.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pola.1993.080310915
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