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Naphthalene-l,4,5,8-tetracarboxylic

A new quality in ladder polymer synthesis via multifunctional polycondensation was reached in the late 1960s when poly(benzimidazobenzo-phenanthroline) (BBL) 12 was prepared by Arnold and van Deusen [21 -24]. The polymer was synthesized from naphthalene-l,4,5,8-tetracarboxylic acid dianhydride (11) and 1,2,4,5-tetraaminobenzene (la) in strong acidic media (polyphosphoric acid, sulfuric acid). BBL is completely soluble in concentratal sulfuric acid or methanesulfonic add and is processible into durable films and... [Pg.6]

In contrast, polynaphthoylenebenziniidazote based on 2,2-bis(3,4-diaminophenyl) hexafluoropropane are soluble not only in H2SO4, m-cresol and a tetrachloroethane-phenol mixture (3 1) (this is characteristic for polymers derived from bis(o-phenylenediamine) and naphthalene-l,4,5,8-tetracarboxylic acid dianhydride [183, 184]) but also in N-MP (N-methylpyrolidane). An enhanced solubility of polynaphthoyleiKbenzimidazoles of this series is explained not only by the introduction of a hinge group between naphthalic anhydride moieties, but also by low viscosity characteristics of the systems caused by low basicity of 2,2-bis(3,4-diaminophenyl)hexafluoropropane [185],... [Pg.149]

Naphthalene-l, 4,5,8-tetracarboxylic acid dianhydride 118, 137, 138, 140, 146, 147 2,6-Naphthalenedicarboxylic acid 196 Nonlinear optical polymers 36... [Pg.226]

Another class of polyimides that are characterised by a higher chain flexibility, when compared to PPI, are based on naphthalene-l,4,5,8-tetracarboxylic acid dianhydride (DNTA). These polymers are of considerable interest due to their high heat resistance and thermal stability and due to easy accessibility of the starting monomers. DNTA is a widely available dianhydride showing the highest electrophilic reactivity among bisfnaphthalene-tetracarboxylic anhydrides [18, 19]. [Pg.19]

Naphthalene-1,8-dicarboxylic add, its nitro-substituted derivatives, and naphthalene-1,4,5,8 tetracarboxylic acid, on treatment with sulfur tetrafluoride at 0 C, undergo dehydration to form quantitatively the corresponding anhydrides [218, 221] Unsubstituted and mononitrated monoanhydndes react further at 200-250 °C to give derivatives of 1,1,3,3-tetrafluoro-l// naphtho[I,8 c,d]pyran Dinitronaphthalene-l,8-di-carboxyhc acid anhydndes and naphthalene 1,4,5,8 tetracarboxylic acid dianhydnde give the respective tetra- and octafluoroethers only in the presence of an excess of anhydrous hydrogen fluoride [221] (equabons 113 and 114)... [Pg.248]

Starting from a 1 2 mixture of an electron-rich bis-l,5-(dinaphtho)-38-crown-10 and the electron-poor bis-acetylenic compound 1, Sanders used the template effect obtained by the inclusion of the pyromellitic diimide 1 in the crown ether to direct the oxidative coupling of the terminal alkynes toward the formation of the cyclized structure, the [2]catenane, with a 38% chemical yield. When 1 was replaced by a more electron-poor moiety obtained from 1,4,5,8-naphthalene tetracarboxylic diimide (2, Scheme 17.5) the yield of the catenane improved to 52%. [Pg.327]


See other pages where Naphthalene-l,4,5,8-tetracarboxylic is mentioned: [Pg.136]    [Pg.334]    [Pg.378]    [Pg.119]    [Pg.119]    [Pg.139]    [Pg.232]    [Pg.136]    [Pg.334]    [Pg.378]    [Pg.119]    [Pg.119]    [Pg.139]    [Pg.232]    [Pg.705]    [Pg.705]    [Pg.7]    [Pg.705]    [Pg.705]    [Pg.507]    [Pg.363]    [Pg.82]    [Pg.146]   


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1,4,5,8-naphthalene tetracarboxylic

L- naphthalene

Naphthalene-l,4,5,8-tetracarboxylic acid dianhydride

Tetracarboxyl

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