Synthesis of poly(p-phenylene vinylene) and derivatives via a new precursor route, the dithiocarbamate route

A new synthetic route towards poly(para-phenylene vinylene) (PPV) and its derivatives has been investigated. In this route, a bis-dithiocarbamate monomer is polymerized towards a dithiocarbamate precursor polymer by the addition of a strong base (LDA). The corresponding conjugated polymer is obtained via a heat treatment of the precursor polymer. This dithiocarbamate (DTC) precursor route strikes an optimal balance between several straightforward but sometimes troublesome precursor routes and the more complex sulphinyl precursor route yielding superior purity materials. The novelty lies in the fact that the monomer synthesis is not as difficult as compared to the sulphinyl route and this without losing the quality and accessibility of the precursor polymer. In the paper, the mechanism of the polymerization process is discussed and strong indications for radical as well as anionic mechanisms are presented.