We have prepared two xanthate precursor polymers (6) and one sulfinyl precursor oligomer (7). In this way the polymerization behavior of three xanthate-containing monomers (3, 4, and 5) was studied. The chemical modifications on the monomer stage allowed to evaluate the outcome of the polymerization in relation to the chemical structure of the monomer. Polymerizations were performed in dry THF at different temperatures. The thermal conversion to the conjugated PPV structure, as well as its stability, was studied with different analytical techniques such as in-situ FT-IR spectroscopy, in-situ UV-vis spectroscopy, thermogravimetric analysis (TGA), and direct insert probe mass spectroscopy (DIP-MS). By combining the information obtained from these techniques, we were able to obtain a very detailed picture about the elimination process. These measurements also confirmed the formation of cis double bonds in xanthate precursor polymers on conversion. However, subsequent cis-trans isomerization in the end leads toward an all-trans-PPV polymer.

The synthesis and characterization of poly(pyridine vinylene) (PPyV) via the nonionic sulfinyl precursor route is presented. Starting from an unsymmetrical monomer, precursor polymers were prepared in various solvents, which led to polymers with variable molecular weights. The thermal conversion to the conjugated structure, as well as its stability, was studied with different techniques such as FT-IR, UV-vis, TGA, and direct insertion probe mass spectroscopy (DIP-MS). From these results we were able to derive the most suitable conditions to perform the conversion. The fully conjugated PPyV was further characterized with photoluminescence (PL) and cyclic voltammetry (CV) measurements. The PL efficiency was found to be as high as 14%. The CV measurements showed that the polymer can be reduced (ndoped).

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