Arylene vinylene polymers

This survey has demonstrated that the field of conjugated arylene vinylene polymers has matured considerably over the past thierty years. Several synthetic approaches to poly(arylene vinylenejs have been developed, and many routes now allow solution casting of polymeric materials, thereby facilitating incorpora-... 

Table 3.8 Examples for Commercially Available Poly(arylene vinylene) Polymers...

Lutsen L, Vanderzande D, Banishoeib F. Functionalization of poly(arylene-vinylene) polymers for electronic devices. US Patent 8173999, assigned to IMEC, Leuven, BE/ Universiteit Hasselt, Diepenbeek, BE 2012. 

Under optimum conditions (e.g. [RuCl2(CO)3]2) linear trans-isiciic (silylene,siloxylene)-vinylene, alkylene-silylene, and silylene-arylene-vinylene polymers (Mw = 7100-7900 Mw/Mn = 1.5-1.84) have been synthesized. 

Photoluminescent silylene-arylene-vinylene polymers can be also obtained via platinum- or rhodium-catalyzed polyaddition of dihydrosilanes to diethyny-larenes. 

Garay, R. O., Karasz, F. E., and Lenz, R. W., Synthesis and properties of phenyl-substituted arylene vinylene polymers and copolymers, J.M.S. Pure Appl. Chem., A32, 905-923 (1995). 

J. D. Capistran, D. R. Gagnon, S. Antoun, R. W. Lenz, and F. E. Karasz, Synthesis and electrical conductivity of high molecular weight poly(arylene vinylene), Polym. Prepr. 1984.2S2. 

Arylene vinylene polymers, such as poIy(p-phenylene-vinylene) (PPV) and poly(2,5-thienyleneviryIene) (PTV) have been studied extensively over the past 10 years due to the relative ease of producing high quality thin films via the soluble precursor route [48-52]. PPVs in particular have been shown to be true multifunctional materials, displaying enhanced third-order NLO properties as well as applications as light-emitting diodes [53,54]. PPV pre-... 

Poly(arylene vinylenes). The use of the soluble precursor route has been successful in the case of poly(arylene vinylenes), both those containing ben2enoid and heteroaromatic species as the aryl groups. The simplest member of this family is poly(p-phenylene vinylene) [26009-24-5] (PPV). High molecular weight PPV is prepared via a soluble precursor route (99—105). The method involves the synthesis of the bis-sulfonium salt from /)-dichloromethylbenzene, followed by a sodium hydroxide elimination polymerization reaction at 0°C to produce an aqueous solution of a polyelectrolyte precursor polymer (11). This polyelectrolyte is then processed into films, foams, and fibers, and converted to PPV thermally (eq. 8). 

Heteroaromatic ring stmctures can also be incorporated into poly(arylene vinylene) stmctures using the same precursor polymer method shown for PPV. Poly(thienylene vinylene) (13) (113—118) and poly(furylene vinylene) (14) (119,120) have been prepared in this manner. In addition, alkoxy-substituted poly(thienylene vinylenes) (15) (119,121) have been synthesized. Various copolymers containing phenjiene, thienylene, and furylene moieties have also been studied (120,122,123). 

Because of the aqueous solubiUty of polyelectrolyte precursor polymers, another method of polymer blend formation is possible. The precursor polymer is co-dissolved with a water-soluble matrix polymer, and films of the blend are cast. With heating, the fully conjugated conducting polymer is generated to form the composite film. This technique has been used for poly(arylene vinylenes) with a variety of water-soluble matrix polymers, including polyacrjiamide, poly(ethylene oxide), polyvinylpyrroHdinone, methylceUulose, and hydroxypropylceUulose (139—141). These blends generally exhibit phase-separated morphologies. 

Polyfarylene vinylene)s form an important class of conducting polymers. Two representative examples of this class of materials will be discussed in some detail here. There are poly(l,4-phenylene vinylcne) (PPV) 1, poly(l,4-thienylene viny-lenc) (PTV) 2 and their derivatives. The polymers are conceptually similar PTV may be considered as a heterocyclic analog of PPV, but has a considerably lowci band gap and exhibits higher conductivities in both its doped and undoped stales. The semiconducting properties of PPV have been shown to be useful in the manufacture of electroluminescent devices, whereas the potential utility of PTV has yet to be fully exploited. This account will provide a review of synthetic approaches to arylene vinylene derivatives and will give details an how the structure of the materials relate to their performance in real devices. 

Fig. 6. Synthetic routes to conjugated polymers via precursor polymers for (a) polyacetylene, and (b) arylene vinylenes.

U. Scherf and K. Mullen, Polyarylenes and poly(arylene vinylenes), 7. A soluble ladder polymer via bridging of functionalized poly(p-phenylene)-precursors, Makromol. Chem., Rapid Commun., 12 489-497, 1991. 

A number of poly(arylene vinylene) (PAV) derivatives have been prepared. Attachment of electron-donating substituents, such as dimethoxy groups (structure 19.3), acts to stabilize the doped cationic form and thus lower the ionization potential. These polymers exhibit both solvatochromism (color changes as solvent is changed) and thermochromism (color is temperature-dependent). 

An extensive review of the synthesis of rc-conjugated polymers is presented using a tutorial approach to provide an introduction to the field intended for the undergraduate student and the experienced chemist alike. The many synthetic methodologies that have been used for the synthesis of conjugated polymers are outlined for each class of polymers with a focus on research from the 1990s. The effect of structure on electrical properties is detailed. Specific systems reviewed include the polyacetylenes, polyanilines, polypyrroles, polythiophenes, poly(arylene vinylenes), and polyphenylenes. 

Keywords Conducting polymers, Conjugated polymers, Polyacetylenes, Polyanilines, Polypyrroles, Polythiophenes, Poly(arylene vinylenes), Polyphenylenes... 

Conjugated polymers like poly(l,4-phenylene-vinylene), PPV, or more generally Poly(arylene-vinylenes), PAVs have evoked considerable interest as electrically conductive and nonlinear optical materials. More recently, electroluminescence properties of PPV have attracted substantial attention, since it was first reported in 1990. Direct synthesis of PPV has been limited by its insolubility. Hence, the most commonly used routes are based on soluble polymer precursors or soluble conjugated precursors. The latter process is also commonly referred to as the sulfonium-based polyelectrolyte precursor route. PPV thin films from these solution-based routes, however, have problems related to contamination by solvents and oxidative defects in the polymer. C VP is an alternate method for the deposition of high quality thin films of PPV. Reported first by Iwatsuki et al., it was investigated for electroluminescence applications by Staring et al. ... 

Scheme 5.4. Synthesis of poly arylene vinylene)s obtained by the elimination of small molecules from a precursor polymer.

Numerous articles have appeared on poly(arylene vinylene) systems, acetylenes and related polymers. The temperature dependence of the photoluminescence from poly(p-phenylene vinylene) (PPPV) has been examined in terms of its influence on diffusion rates while a magnetic field has been found to enhance luminescence intensity. A series of poly(alkoxyphenylenes) have been synthesised with high luminescence quantum yields whereas vapour deposited poly(p-phenylene vinylene) has been found to have an unidentifiable defect structure when annealed at high temperatures. ... 

Egbe, D.A.M., Cornelia, B., Nowotny, J., Gunther, W., and Klemm, E. 2003. Investigation of the photophysical and electrochemical properties of alkoxy-substituted arylene-ethynylene/ arylene-vinylene hybrid polymers. Macromolecules 36, 5459-5469. 

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