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Phenylene-type ladder polymers

Poly(parfl-Phenylene)-Type Ladder Polymers... [Pg.235]

W. Graupner, G. Leising, G. Lanzani, M. Nisoli, S. De Silvestri, U. Scherf, Femtosecond relaxation of photoexcitations in a poly(para-phenylene)-type ladder polymer Phys. Rev. Lett. 1996. 76, 847. [Pg.329]

MeLPPP methyl-substituted poly(para-phenylene)-type ladder polymer... [Pg.654]

U. Scherf, K. Muellen, Poly(Arylenes) and Poly(Arylenevinylenes). 11. A Modified Two-Step Route to Soluble Phenylene-Type Ladder Polymers. Macromolecules 1992,25, 3546-3548. [Pg.111]

In 1993, Scherf and Chmil described the first synthesis of a ladder-type poly(pflra-phenylene-czs-vinylene) (116) [138]. On the one hand, ladder polymer 116 represents, a planar poly(phenylene) containing additional vinylene bridges on the other hand, it is a poly(phenylenevinylene) with aryl-aryl linkages in the polymeric main chain. The target macromolecules, as fully aromatic ladder polymers, are composed of all-carbon six-membered rings in the double-stranded main chain (an example of angularly annelated poly(acene)s). [Pg.216]

The synthesis of fully conjugated semiconducting para-phenylene ladder polymers by microwave-assisted palladium-mediated double Suzuki and Stille-type reactions has been demonstrated by Scherf and coworkers (Scheme 6.27) [58], The procedure, which yields polymeric material in ca. 10 min, has no adverse effects on the quality of the polymers and displays a high degree of reproducibility. Compared... [Pg.124]

Polymers containing cyclophane-type moieties were also prepared for their unique functionalities and potential applications. Thus, isotactic poly(para-phenylene) ladder polymer (56) was prepared from the corresponding bromide and borate (55) in enantiomerically pure forms and subjected to the CD spectral measurement [62],... [Pg.121]

The formation of the polymeric carbanions 81 of the fluorenyl-type is successful starting from the poly(para-phenylene) ladder polymer 71 with butyl-lithium as metallating agent. The degree of lithiation lies in the range of 90-95% (NMR). The UV/VIS absorption spectrum of these polymeric anions (81) is comparable with that of the 9-phenylfluorenyl anion and indicates the presence of mostly localized (anionic) sub-structures [101]. [Pg.32]

The synthetic sequence to methylene-bridged poly(phenylene)s 71 represents the first successful employment of the stepwise process to ladder-type macromolecules involving backbone formation and subsequent polymer-analogous cyclization. As shown, however, such a procedure needs carefully tailored monomers and reaction conditions in order to obtain structurally defined materials. The following examples demonstrate that the synthesis of structurally defined double-stranded poly(phenylene)s 71 (LPPP) via a non-concerted process is not just a single achievement, but a versatile new synthetic route to ladder polymers. By replacing the dialkyl-phenylenediboronic acid monomer 68 by an iV-protected diamino-phenylenediboronic acid 83, the open-chain intermediates 84 formed after the initial aryl-aryl cross-coupling can te cyclized to an almost planar ladder-type polymer of structure 85, as shown recently by Tour and coworkers [107]. [Pg.33]

Polyphenylene-type Emissive Materials Poly(para-phenylene)s, Polyfluorenes, and Ladder Polymers... [Pg.298]

Scheme 5 Synthesis of methylene-bridged ladder polymers of the poly(pa/-a-phenylene) type (LPPP). Scheme 5 Synthesis of methylene-bridged ladder polymers of the poly(pa/-a-phenylene) type (LPPP).
Surprisingly, if a solution of the polyalcohol was treated with boron trifluoride etherate in, e.g., dichloro-methane or chloroform, the ring closure to give the ladder polymer took place within seconds and was quantitative. The resulting new type of ladder polymer, a planar methylene-bridged poly(p-phenylene), is deep yellow, and solutions thereof display an extremely intense blue photoluminescence. [Pg.366]

PDA polydiacetylene BMCU butoxycarbonylmethylurathane group PTS para-toluene sulfonate irares-PA irares-polyacetylene PAZ polyazine PI poyimide PQ polyquinoline PPV poly(p-phenylene vinylene) PT poljdhiophene PBZO poly(p-phenylene benzobisoxazole) PBZT poly(p-phenylene benzobisthiazole) BBL and BBB benzimidazophenanthroline-type heteroaromatic ladder polymer. [Pg.830]

See other pages where Phenylene-type ladder polymers is mentioned: [Pg.12]    [Pg.12]    [Pg.445]    [Pg.574]    [Pg.575]    [Pg.31]    [Pg.235]    [Pg.654]    [Pg.12]    [Pg.12]    [Pg.445]    [Pg.574]    [Pg.575]    [Pg.31]    [Pg.235]    [Pg.654]    [Pg.163]    [Pg.148]    [Pg.351]    [Pg.481]    [Pg.555]    [Pg.8]    [Pg.28]    [Pg.29]    [Pg.33]    [Pg.36]    [Pg.119]    [Pg.45]    [Pg.270]    [Pg.330]    [Pg.4]    [Pg.358]    [Pg.14]    [Pg.3]    [Pg.5119]    [Pg.5120]    [Pg.830]    [Pg.363]    [Pg.364]    [Pg.365]    [Pg.871]    [Pg.357]    [Pg.40]   
See also in sourсe #XX -- [ Pg.574 ]



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