Naphthalenic dianhydride

Einsla, B. R., Hong, Y. T., Kim, Y. S., Wang, F., Gunduz, N. and McGrath, J. E. 2004. Sulfonated naphthalene dianhydride based polyimide copolymers for proton-exchange-membrane fuel cells. 1. Monomer and copolymer synthesis. Journal of Polymer Science Part A Polymer Chemistry 42 862-874. 

Compared to fluoropolymers, aliphatic and aromatic polymers are less hydrophobic, and the sulfonic acid functional group is less acidic and less polar. Nafion is a superacid, with a piCa -6 as estimated using pJCa database 4.0 [130]. Ma et al. [131] determined the pKa of Nafion 117 and the sulfonated aromatic polymer, BPSH (Scheme 3b), to be -3.09 and -2.04, respectively, while the simplest aromatic sulfonic acid, benzene sulfonic acid, has a pJCa of 0.70 [132]. Aromatic polymers are more rigid than Nafion and possess shorter ionic side chains, and therefore are expected to exhibit a lesser degree of separation between hydrophilic and hydrophobic domains. SAXS measurements on rigid aromatic polymers, such as SPIs based on naphthalenic dianhydride (Scheme 3k, x = 5, xly = 30/70) indicate the ab-... 

Badami AS, Roy A, Lee HS, Li Y, McGrath JE. Morphological investigations of disulfonated poly(arylene ether sulfone)-fe-naphthalene dianhydride-based polyimide multiblock copolymers as potential high temperature proton exchange membranes. J Membr Sci 2009 328 (l-2) 156-64. 

E.A. Mistri, A.K. Mohanty, S. Banerjee, H. Komber, B. Voit, Naphthalene dianhydride based semifluorinated sulfonated copoly(ether imide)s synthesis, characterization and proton exchange properties, J. Membr. Sci. 441 (2013)168-177. 

As reported by Genius et al. [48] from a study on model compoimds, sulfonated naphthalenic polyimides prove to be more resistant to hydrolysis than their phthalic analogues. Few articles are devoted to the synthesis and characterization of sulfonated phthalic polyimides, whereas sulfonated naphthalenic polyimides have attracted much attention [53]. Rather few different naphthalenic dianhydride monomers are reported for the synthesis of SPIs (Fig. 2). 

Indeed, besides the perylene tetracarboxylic dianhydride (PTDA) used by Lee et al. [54] and the bisimide dianhydride synthesized by Kim [55], only two new naphthalenic dianhydrides have been described. In this respect, 4,4 -ketone dinaphthalene l,l, 8,8 -tetracarboxyUc dianhydride (KDNTDA, Fig. 3) is obtained through a multistep synthesis, with a 19% overall yield [56]. 

However, it should be noted that most works related to SPI synthesis involve 1,4,5,8-naphthalenetetracarboxyUc dianhydride (NTDA) as naphthalenic dianhydride. The sulfonic acid groups are incorporated into the... 

Chen, X., Yin, Y., Tanaka, K., Kita, H., Okamoto, K.I. (2006) Synthesis and characterization of novel sulfonated polyimides derived from naphthalenic dianhydride. High... 

The dianhydride of 1,4,5,8-naphthalene tetracarboxyhc acid [81-30-1] has been of research interest for the preparation of high temperature polymers, ie, polyimides. The condensation of the dianhydride with o-phenylenediamines gives vat dyes and pigments of the benzimidazole type. 

Pigment Orange 43 [4424-06-0] 71105 Perinone condensation of naphthalene-1,4,5,8-tetracarboxyhc acid dianhydride with o-phenylenediamine, and separation of trans isomer... 

NaOH-catalyzed resole resin, 409 Naphthalene diisocyanate (NDI), 201 Naphthalene tetracarboxylic dianhydride (NDTA), 282... 

Perylene pigments include the dianhydride and diimide of perylene tetracarboxylic acid along with derivatives of the diimide while perinone pigments are derived from naphthalene tetracarboxylic acid. 

The primary starting material for the synthesis of perylene tetracarboxylic acid pigments is the dianhydride 71. It is prepared by fusing 1,8-naphthalene dicar-boxylic acid imide (naphthalic acid imide 69) with caustic alkali, for instance in sodium hydroxide/potassium hydroxide/sodium acetate at 190 to 220°C, followed by air oxidation of the molten reaction mixture or of the aqueous hydrolysate. The reaction initially affords the bisimide (peryldiimide) 70, which is subsequently hydrolyzed with concentrated sulfuric acid at 220°C to form the dianhydride ... 

The acid, referred to as tetra acid , is prepared as follows In a Friedel-Crafts reaction, acenaphthene 72 is reacted with malonic dinitrile and aluminum chloride. The resulting condensation product 75 is oxidized with sodium chlorate/hy-drochloric acid to form the dichloroacenaphthindandione 76. Oxidation with sodium hypochlorite solution/sodium permanganate affords naphthalene tetracar-boxylic acid 68, mostly existing as the monoanhydride 68a. The dianhydride, on the other hand, evolves only after drying at approx. 150°C. 

Dibenzothiophene acts as a 7r-electron donor and readily forms complexes with known electron acceptors. In such cases the electronic spectrum of a solution of the two compounds shows a new absorption band, usually in the visible region. The order of donor strengths of several o,o -bridged biphenyls has been estimated from their respective charge-transfer spectra and found to be carbazole > fluorene > dibenzothiophene >dibenzofuran. Dibenzothiophene forms complexes with tetracy-anoethylene, various polynitro derivatives of fluorenone, > naphthalene-1,4,5,8-tetracarboxylic acid dianhydride, and tetra-methylmic acid. ... 

Perinones are structurally similar to perylenes being made by condensing naphthalene tetracarboxylic dianhydride with amines, but in this case 1,2-diamines, e.g. Cl Pigment Orange 43 (2.71), or its cis isomer. The isomers can be separated by fractionation of their salts. They offer orange to bordeaux shades with similar properties to perylenes, but are less commercially important. 

Aromatic hydrocarbons which have methyl side chains mainly behave like toluene and form aldehydes, while combustion is stimulated and selective oxidation of the nucleus is repressed. The oxidation of methyl-naphthalene, for example, exhibits a low selectivity with respect to phtha-lic anhydride formation, combustion and maleic acid formation being the dominating reactions. Durene is a special case because it resembles o-xy-lene. The oxidation of durene over a V—W—O catalyst at 420° C is reported to produce pyromellitic dianhydride, phthalic and maleic anhydride, although combustion dominates (Geiman et al. [122]). 1,2,4-Trimethyl-benzene yields dimethylbenzene and trimellitic acid if oxidized on a Sn— V—O catalyst. Kinetic data have been measured by Balsubramanian and Viswanath [37]. 

Perinones. The most important pigment in this family is the orange perinone, Pigment Orange 43 [4424-06-0] which is obtained by reaction of naphthalene-1,4,5,8-tetracarboxylic dianhydride with tf-phenylenediamine. The result is a mixture of the cis- and trans-isomers. The commercial product is the orange trans-compound which must be separated from the dull, bluish red cis-isomer, and then conditioned for pigment use. The pigment is fairly weatherfast and heat stable, and is used primarily in plastics and fiber applications. 

The proposed reduction process for 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTDA)-, PMDA-, and BPDA-polyimides involves two sequential one-electron transfers to generate the radical-anion and dianion states respectively. In the case of BPDA-polymers, the formation of a diradical-dianion on the second reduction might be more energetically favored over the... 

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