Poly arylene vinylene s

Poly(p-phenylene vinylene) (PPV) belongs to the class of electroluminescent conjugated polymers. These materials emit light when electric current is passed through them. For this reason, a substantial interest emerges in the field of organic semiconductors. 

A lot of papers have appeared dealing with this topic, often focused on the physical aspects, however there are reviews dealing with chemical aspects, such as synthesis of these polymeric types.  

4-Bis-(dichloromethyl)-benzene a, a-Dibromo-p-xylene Chlorinated cyclophanes Standard procedure For several reaction pathes Chemical vapor deposition  

Poly(p-phenylene vinylene) Poly(p-pyridyl vinylene) 

Poly(p-thienyl vinylene) Poly(p-phenylene ethinylene) 

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Poly(arylene vinylene)s — Synthesis and Applications in Semiconductor Devices... 

W.J. Mitchell, C. Pena, and P.L. Bum, Thermal routes to low HOMO-LUMO energy gap poly(arylene vinylene)s, J. Mater. Chem., 12 200-205, 2002. 

Fig.l General schematic structures of poly(arylene ethynylene)s (PAEs), poly(arylene)s (PAs), poly( arylene vinylene)s (PAVs), and poly (diacetylene) s (PDAs)... 

Haloarene derivatives used for coordination polycondensation are primarily represented by halostyrenes and haloarylacetylenes which undergo selfcoupling to poly(arylene vinylene)s [scheme (2)] and poly(aryleneacetylene)s [scheme (3)] respectively, and by dihaloarenes which, mainly in a combination with alkenes or divinylarenes and acetylenes or diacetylenes, undergo crosscoupling to poly(arylene vinylene)s [schemes (4) and (5)] and poly(arylene acetylene)s [schemes (6) and (7)] respectively [2] ... 

The transition metal-catalysed coupling of aryl halides with alkenes (alkenyla-tion of aromatic halides) is referred to as the Heck reaction [66-75]. Heitz et al. [76-82] were the first to utilise the Heck reaction to synthesise high molecular weight poly(arylene vinylene)s by the self-coupling of bromostyrene [scheme (2)] or the cross-coupling of dibromoarene with ethylene [scheme (4)] or divi-nylarene [scheme (5)]. 

The application of Heck coupling polycondensation is not limited to the synthesis of poly(arylene vinylene)s via the alkenylation of haloarenes in simple monomer systems but includes a variety of self- and cross-coupling reactions involving reactants with various functionalities. For instance, the polycondensation of diiodoarene with bis(acrylamido)arene by the Pd(OOCCH3)2—P (o-C6H4—CH3)3 catalyst yields respective aromatic polycinnamamide [106] ... 

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

Poly(arylene 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 vinylene) (PPV) 1, poly(l,4-thienylene vi-nylene) (PTV) 2 and their derivatives. The polymers are conceptually similar PTV may be considered as a heterocyclic analog of PPV, but has a considerably lower band gap and exhibits higher conductivities in both its doped and undoped states. 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. 

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