Phenylene-Containing Polymers

From Marvel s early paper comparative ITG data are also available, which show the m-phoi 4ene-containing prototype i, after stepwise heating in nitrogen for Ih e at 400,450,500,550, and 600 °C, to have lost only a total of 4.5% of its initial weight. Very similar performance data are evident firm Marvel s tabulation for the p-phenylene-containing polymer and various otter aromatic types. The multitude of TG and ITG... 

The introduction of a phenylene group into an epoxy polymer structure raises the sound speed. These polymers and other phenylene-containing polymers, such as polycarbonate, polysulfone, and polylether sulfone), all have relatively high sound speeds (65). The aromatic ring imparts a conformational rigidity to the backbone structure of these poljuners, which is responsible for the high sound speed. 

Research activities in the area of PODs containing aromatic groups have been centered around the production of highly processible, soluble, and thermally stable polymers. In this particular class of PODs, the imide-and phenylene-containing backbones have been widely explored. 

The Eastman Chemical Company has pubHshed extensively in the patent Hterature (65—74) and the scientific Hterature (75—77) on processes for making poly(phenylene sulfide)- (9-(phenylene disulfide), and related copolymers. The Eastman process involves the reaction of elemental sulfur with Ndiiodobenzene to yield a phenylene sulfide polymer that also contains phenylene disulfide repeating units in the polymer. The fraction of repeating groups containing... 

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). 

The most prominent application of the Ru-arene chemistry has been for the preparation of biaryl ethers in the syntheses of portions of vancomycin,467 ristocetin (Equation (127)),462,468-473 and teicoplanin (see also Section 10.14.1.2).474-476 Additional applications477-479 have included the syntheses of the macrocyclic biaryl ether-containing compounds K-13480,481 and OF4949-III,481,482 several macrocyclic depsipeptides,483,484 and poly(phenylene oxide) polymers.485... 

Kohler A, Wilson JS, Eriend RH, Al-Suti MK, Khan MS, Gerhard A, Bassler H (2002) The singlet-triplet energy gap in organic and Pt-containing phenylene ethynylene polymers and monomers. J Chem Phys 116 9457... 

Navarro [36] has reported several soluble, low transition temperature MCLC polymers containing ortho- or para-linked units and cinnamates or phenylene-fcis-acrylates in the main chain. One series of cinnamate-containing polymers is shown as 9. Some of the polymers seemed to be partially crystalline in the solid state. All had N and/or S mesophases which were retained in the solid glasses upon cooling to room temperature. Some of the polymers underwent thermal degradation and cross-linking above 300°C. Irradiation ( max = 300 nm)... 

Burning may be considered another means of oxidation. Non-burning plastics are a must in commercial constructions according to building codes and are often required for automotive, electronic, and electrical applications. From the numerous thermoplastics, only the halogen-containing polymers, polyamides, polycarbonate, poly(phenylene oxide), polysulfone, and polyimides are self-extinguishing. Even these, such as poly (vinyl chloride), may become flammable when plasticized with a flammable plasticizer. Fire control can be the key to volume use of plastics. Polyester panels, urethane foam, and PVC tarpaulins account for nearly 90% of all fire retardants consumed. Consumption in 1967... 

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],... 

Vukovic R, Bogdanic G, Karasz FE and MacKnight WJ (1999) Phase behavior and miscibility in binary blends containing polymers and copolymers of styrene, of 2,6-dimethyl-1,4-phenylene oxide and of their derivatives. J Phys Chem Ref Data 28 851-68. 

FIGURE 9.1. Repeat units of the pyridine-containing polymers and other polymers used in the study (a) poly(p-pyridine) (PPy) (b) poly(/ -pyridyl vinylene) (PPPyV) (c) copolymer of PPY and PPyV [PPyVP(R)2V] (d) wrapped copolymer of pyridylvinylene and penylenevinylene ( PPyVPV) (e) wrapped copolymer of dithienylene and phenylene ( PTP) (f) emeraldine base (EB) form of polyaniline (g) sulfonated polyaniline (SPAN). 

A variety of different functionalities were introduced into this class of polymers by conversion of the zirconacyclopentadiene units (Scheme 2.35).205-206 The reaction of polymer 124 with dimethylaceteylene dicarboxylate 125 in the presence of CuCl/LiCl produced the phenylene-based polymer 126 as an example. Polymers containing thiophene and phosphole units 127 were also prepared. 

Yamamoto has synthesized a variety of zinc porphyrin-containing polymers (29-35) with arylene and aryleneethynylene linkers.42 Arylene groups incorporated included 2,5,-dialkoxy-1,4-phenylene, 3-alkyl-2,5-thiophenyl, and 2-alkyl-3,6-pyridenyl species. Due to their long substituents, these polymers are soluble in THF and have molecular weights of 4600-38,000 Da (A/n, GPC). Powder X-ray diffraction revealed some degree of order in the thin films prepared from polymers with long alkyl substituents. Photoluminescence, thermal analysis, and CV of the new polymers were also reported. 

Polyheterocycles can even be made by polymer analogous reactions. A good example of this is the formation of oxadiazole-containing polymers. Thus, Janietz et al. [86] prepared the precursor polymers 89 by the polycondensation of 90 with 91 and then dehydrated it with phosphorus oychloride to give the phenylene oxadiazole copolymers 69 (Scheme 6.21). 

The thermal behaviour of sulphur containing polymers has been reported on [302]. The major breakdown in poly(l,4-phenylene sulphide)... 

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