- 2,3,6,7-Naphthalenetetracarboxylic dianhydride revisited
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2,3,6,7-Naphthalenetetracarboxylic dianhydride was prepared and characterized by UV, IR, and NMR spectra. Its structure was confirmed by single crystal X-ray determination. It is a moderate strength electron acceptor, stronger than p-benzoquinone and weaker than pyromellitic anhydride according to quantum mechanical calculations and electrochemical measurements.
- Niebel, Claude,Lokshin, Vladimir,Khodorkovsky, Vladimir
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- Functionalized Photoreactive Compounds
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The present invention concerns functionalized photoreactive compounds of formula (I), that are particularly useful in materials for the alignment of liquid crystals. Due to the adjunction of an electron withdrawing group to specific molecular systems bearing an unsaturation directly attached to two unsaturated ring systems, exceptionally high photosensitivities, excellent alignment properties as well as good mechanical robustness could be achieved in materials comprising said functionalized photoreactive compounds of the invention.
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- Compounds, polymers, resin compositions and nonlinear optical devices
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The present invention provides, as heteroaromatic compounds made functional so as to be used for nonlinear optical materials, compounds represented by the following general formula (1), and also provides polymers obtained from these and nonlinear optical parts comprising such polymers. In the formula, Ar1 and Ar2 each represents a divalent aromatic group; R1, R2 and R3 each represents an atom or a group independently selected from a hydrogen atom or an alkyl group and an aromatic group; X1 represents a monovalent organic group; n represents an integer of 2 to 12; and Z1 and Z2 each represents a group independently selected from electron attractive functional groups.
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- O-substituted N-hydroxy hindered amine stabilizers
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Hindered amines based on various 2,2,6,6-tetraalkylated nitrogen-containing heterocyclic moieties wherein the hindered nitrogen atom on the ring is substituted with OR1 substituents and the 4-position of the ring is substituted with a variety of groups, are effective as light stabilizers in diverse substrate systems.
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- N-cyanoimides
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Polyfunctional N-cyanoimides and their precursors and derivatives are disclosed along with methods for their preparation and interconversion. Also disclosed are curable compositions comprising the N-cyanoimides or poly(amide-cyanoamides) and reactive diluents as well as novel dianhydrides, polyimides, and poly(amide-cyanoamides) and methods for making them.
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- Diamines and photosensitive polyimides made therefrom
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Disclosed is an aromatic diamine having the general formula where A is a group containing at least one aromatic ring, each Y is independently selected from or -OR, R is a group containing at least one olefinically unsaturated group, R' is hydrogen, alkyl to C25, aryl, or R, n is 1 to 4, and the number of olefinic groups in Y is at least 3 when each Y is and otherwise is at least 2. Photosensitive polyamic acids and polyimides can be prepared from the aromatic diamines which can be crosslinked with light to a mask to form patterns on a substrate.
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- Synthesis of Bis-2,7-substituted 1,2,3,6,7,8-Hexahydroisoindoloisoindole-1,3,6,8-tetraones
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A series of bis-2,7-substituted 1,2,3,6,7,8-hexahydroisoindoloisoindole-1,3,6,8-tetraones (naphthalene diimides) has been synthesized.The key intermediate required for synthesis of the naphthalene diimides, 2,3,6,7-naphthalenetetracarboxylic dianhydride (2) was prepared starting from allene and maleic anhydride.The bis-anhydride 2 was converted to the naphthalene diimides using conventional methodology by the reaction with amines in organic solvents.
- Boykin, D. W.,Nowak-Wydra, Barbara,Baumstark, A. L.
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p. 609 - 611
(2007/10/02)
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- Bis-(maleamic acid) derivatives of triamines
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The compositions described herein comprise polyimides having bis-maleimide terminal groups and having the formula: STR1 wherein Q is a trivalent aromatic radical, Ar is a divalent aromatic radical, Ar" is a tetravalent aromatic radical and n has a value of 0-20. Derivatives may be made of these compounds by homopolymerization, copolymerization with other copolymerizable materials and by reaction with Diels-Alder reactable materials.
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