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The prerequisites for the polymerization process of sulfinyl monomers toward precursor polymers for poly(p-phenylenevinylene) were investigated. In this process, proton abstraction affords the premonomer anion, which is converted to the actual monomer, viz. a p-xylylene derivative. These p-xylylene derivatives polymerize spontaneously without external initiation. In hydrogen bond donor solvents (HBD solvents) like alcohols, three products can be isolated. High molecular weight polymer is formed together with a residual fraction that consists of a minor amount of premonomer and a large amount of solventsubstituted product. These solvent-substituted products are most likely formed by addition of a solvent anion to the actual monomer and cannot participate in the polymerization process anymore. Solvent substitution is therefore an important side reaction and has to be avoided. It was found that, in branched alcohols such as s-butanol, conversion of premonomer to actual monomer is very efficient, resulting in a rapid buildup of p-xylylene derivative. In this way the polymer yield was increased to 90%.

A new precursor route for poly(arylene vinylene) derivatives will be presented. In this way non‐ionic precursor polymers are obtained which show an enhanced thermal stability and are soluble in organic solvents. This enables a thorough structural characterization and the study of the mechanism. Experiments have been performed to differentiate between a radical or an ionic polymerization mechanism. Furthermore possibilities to tune solubility characteristics and to introduce defects in the polymer backbone will be discussed. Also the scope for this new route was explored. The first results indicate that the versatility exceeds that of the Wessling route, e.g. the synthesis of precursors for poly(p‐biphenylene vinylene) and poly(2,6‐naphthylene vinylene) could be accomplished in our case, whereas it failed in the case of the Wessling route.

A synthesis route to soluble high molecular weight poly(p-xylylene) derivatives has been investigated. This method provides a versatile route to poly(phenylenevinylene) (PPV) from a precursor polymer that is amenable to the conventional nonaqueous processing techniques. To investigate the mechanism in the solvent mixture, monomethylformamide (MMF)/CH 2Cl2 (60/40), the influence of the leaving group and polarizer of the monomer was studied. The evaluation of the molecular weight of the polymer, the polymer yield, and the residual low molecular weight fraction indicates that only the kind of polarizer has an effect on the reaction in contrast with the leaving group, having no observable effect.

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