Photocrosslinkable polymers bearing pendant conjugated heterocyclic chromophores

This article describes the synthesis of furan- and thiophene-based chromophores bearing a terminal aldehyde function which was used to append them to polyvinyl alcohol (PVA) and thus obtain photosensitive polymers. Because of their conjugated structure, the chromophores absorbed in the near-UV domain and only displayed two photochemical transformation, viz. a trans–cis isomerisation and a bimolecular cyclodimerisation. The latter reaction was exploited to induce the crosslinking of the modified PVAs. The application of these materials as photosensitive resins for lithographic plates is the practical issue of the present investigation.