Polyphenylene vinylene derivatives

Corma Canos [3] prepared electroluminescent materials by encapsulating polyphenylene-vinylene derivatives in an CsX zeolite. 

The following aspects will be addressed. (1) Conjugated polymers with benzene-derived repeat units (section II) typical examples are the already mentioned poly-/>phenylene (PPP) 6,43 polyphenylene-vinylenes (PPV) 9,43 and polyphenyleneethinylenes (PPE) 25.44 Some typical questions are obvious how do the aromatic or olefinic units interact via the formal single bonds and how far does an extra charge or an excitation delocalize over the chain. (2) Large... 

Structural studies of polymer surfaces. Materials that have been studied include PMMA [239], PMMA-polypyrrole composites [240], polyfchloromethyl styrene) honnd 1,4,8,11-tetrazacyclotetradecane, polyfchloromethyl styrene) honnd thenoyl triflnoroacetone [241], poly(dimethyl siloxane)-polyamide copolymers [242], PS [243], ion-implanted PE [244], monoazido-terminated polyethylene oxide [245], polynrethanes [246], polyaniline [247], flnorinated polymer films [248], poly(o-tolnidine) [249], polyetherimide and poly benzimidazole [250], polyfnllerene palladinm [251], imidazole-containing imidazolylethyl maleamic acid-octadecyl vinyl ether copolymer [252], polyphenylene vinylene ether [253], thiophene oligomers [254], flnorinated styrene-isoprene derivative of a methyl methacrylate-hydroxyethyl methacrylate copolymer [255], polythiophene [256], dibromoalkane-hexaflnorisopropylidene diphenol and bisphenol A [257], and geopolymers [258]. 

Another interesting development from Philips, this time in conjunction with the University of Amsterdam, is a simple polymer-based electroluminescent device which can be switched between glowing red or green merely by reversing the current flow. The polymer used is a semi-conducting derivative of polyphenylene vinylene blended with a phosphorescent complex consisting of two... 

Polymer photovoltaics using conducting polymers are also being developed. In a typical arrangement, the photosensitive polymer (such as polyphenylene vinylene (PPV) and its derivatives) is sandwiched between two electrodes (Figure 1.6). One is a transparent material, typically indium tin oxide (ITO)-coated glass, and the other electrode is a low-work-function metal such as aluminum or calcium. Light is absorbed by the polymer. 

Derivatives of polyphenylene vinylene are formed in the Pd-catalyzed reaction of ethylene with substituted dihalogeno arenes. This requires a change of the valence of the metal. In contrast to this the alternating copolymerization of olefins with carbon monoxide and the vinylic polymerization of norbomene is successful only if the two vsdent state of Pd is maintained. The mechanism of the Heck reaction (7) (equation 4) shows the limiting requirements to tune the reaction in one or the other way. 

The educt of acetylene with acetone allows a simple synthesis of polyphenylene ethinylene (77). The absorption of these polymers is in the same range as polyphenylene vinylene. This absorption is reach at a polymerization degree 7-8 also in this case. Oligomers can be used as active components in LED films. The flexibility of catalytic reactions makes a wide variety of derivatives available. 

---