Alkoxy poly

F. Cacialli, B.S. Chuah, R.H. Friend, S.C. Moratti, and A.B. Holmes, Blue-emitting diodes from a m-linked 2,3-substituted alkoxy poly(p-phenylene vinylene), Synth. Met., Ill 155-158, 2000. 

For halogen or alkoxy-substituted polymers Tg values are low (between -60 and —100° C). Alkoxy poly phosphazene with Ci - C3 substituents are elastomers. Higher alkoxy- or aryloxy-substituted polyphosphazenes are thermoplastics. Fluoroalkoxypolyphosphazenes exhibit a good stability toward diluted acids and bases. Some of them have outstanding thermal stability and good flame-retardant properties. 

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). 

Poly[2,5-dialkoxy-l,4-phenylene) vinylenejs with long solubilizing alkoxy chains dissolve in conventional organic solvents such as chloroform, toluene, or tetrahydrofuran [21, 28, 32-36]. Their emission and absorption spectra are red-shifted relative to PPV itself, and the polymers fluorescence and electroluminescence quantum yields are greater than parent PPV. This benefit may be a consequence of the long alkyl chains isolating the polymer chains from each other. 

The sulfonium precursor route may also be applied to alkoxy-substituted PPVs, but a dehydrohalogenation-condensation polymerization route, pioneered by Gilch, is favored 37]. The polymerization again proceeds via a quinomethide intermediate, but die syndicsis of the conjugated polymer requires only two steps and proceeds often in improved yields. The synthesis of the much-studied poly 2-methoxy-5-(2-ethylhexyloxy)-l,4-phenylene vinylene], MEH-PPV 15 is outlined in Scheme 1-5 33, 35]. The solubility of MEH-PPV is believed to be enhanced by the branched nature of its side-chain. 

Allen RW and Allcock HR. Conformational analysis of poly(alkoxy- and aryloxyphosphazene) [J]. Macromolecules, 1976, 9(6), 956-961. 

Abstract In this paper the synthesis, properties and applications of poly(organophos-phazenes) have been highlighted. Five different classes of macromolecules have been described, i.e. phosphazene fluoroelastomers, aryloxy-substituted polymeric flame-retardants, alkoxy-substituted phosphazene electric conductors, biomaterials and photo-inert and/or photo-active phosphazene derivatives. Perspectives of future developments in this field are briefly discussed. 

In these studies cleavage of the endocyclic alkoxy group produces ethylene glycol and since only about 5% was found, it was concluded that hydrolysis proceeds 95% via exocyclic cleavage, in excellent agreement with results found for poly(ortho esters). 

Allcock, H. R., Kugel, R. L., and Valan, K. J., High molecular weight poly (alkoxy- and aryloxyphosphazenes), Inorg. 

Horhold et al. and Lenz et al. [94,95]. The polycondensation provides the cyano-PPVs as insoluble, intractable powders. Holmes et al. [96], and later on Rikken et al. [97], described a new family of soluble, well-characterized 2,5-dialkyl- and 2,5-dialkoxy-substituted poly(pflrfl-phenylene-cyanovinylene)s (74b) synthesized by Knoevenagel condensation-polymerization of the corresponding alkyl-or alkoxy-substituted aromatic monomers. Careful control of the reaction conditions (tetra-n-butyl ammonium hydroxide as base) is required to avoid Michael-type addition. 

For the synthesis of the target structures, it is absolutely necessary to introduce solubilizing substituents in the positions peripheral to the benzoyl substituents. The primary coupling product, 117, a poly(2,5-dibenzoyl-l,4-phenyl-ene) derivative - a poly(para-phenylene) with two benzoyl substituents in each structural unit - is, as expected, very poorly soluble. Highly substituted monomers (2,5-dibromo-l,4-bis(3,4-dihexyloxy-benzoyl)benzene), containing four solubilizing alkoxy groups per monomer unit, allow the synthesis of polymeric materials with M of about 12,000 and M, of about 22,000 [139]. 

IR Isoprene rubber poly (els-1,4-isoprene) PEO Poly(ethylene oxide) a-Alkoxy- >-hydroxy polyethylene oxide... 

T. Ahn, S. Song, and H. Shim, Highly photoluminescent and blue-green electroluminescent polymers new silyl- and alkoxy-substituted poly(p-phenylene vinylene) related copolymers containing carbazole or fluorene groups, Macromolecules, 33 6764-6771, 2000. 

D.A.M. Egbe, S. Sell, C. Ulbricht, E. Birckner, and U.-W. Grummt, Mixed alkyl- and alkoxy-substituted poly[(phenylene ethynylene)-a/t-(phenylene vinylene)] hybrid polymers synthesis and photophysical properties, Macromol. Chem. Phys., 205 2105-2115, 2004. 

D.A.M. Egbe, B. Carbonnier, L. Ding, D. Miihlbacher, E. Birckner, T. Pakula, F.E. Karasz, and U.-W. Grummt, Supramolecular ordering, thermal behaviour, and photophysical, electrochemical, and electroluminescent properties of alkoxy-substituted yne-containing poly(phenylene-viny-lene)s, Macromolecules, 37 7451-7463, 2004. 

H. Liang, J. Yan, and J. Lu, Synthesis and optical characterization of a novel blue luminescent polymer regioregular poly(l-alkoxy-2,4 -m-phenylene vinylene), Synth. Met., 142 143-145, 2004. 

S.-A. Chen and C.-I. Chao, Poly(2-alkoxy-p-phenylene)s as deep-blue light-emitting polymers, Synth. Met., 79 93-96, 1996. 

S. Kim, J. Jackiw, E. Robinson, K.S. Schanze, J.R. Reynolds, J. Baur, M.F. Rubner, and D. Boils, Water soluble photo- and electroluminescent alkoxy-sulfonated poly(p-phenylenes) synthesized via palladium catalysis, Macromolecules, 31 964-974, 1998. 

Y.-H. Kim, J.-H. Ahn, D.-C. Shin, and S.-K. Kwon, Synthesis and characterization of poly (terphenylenevinylene) derivatives containing alkoxy substituents and (or) phenyl pendant group, Polymer, 45 2525-2532, 2004. 

BS Harrison, TJ Foley, AS Rnefely, JK Mwaura, GB Cunningham, TS Kang, M. Boug Lettaya, JM Boncella, JR Reynolds, and KS Schanze, Near-infrared photo- and electroluminescence of alkoxy-substituted poly(p-phenylene) and nonconjugated polymer /lanthanide tetraphenylporphirin blends, Chem. Mater., 16 2938-2947, 2004. 

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