The base-induced polymerization of 1,4-bis(tetrahydrothiopheniomethyl)-2-cyano-5-methoxybenzene dibromide in aqueous acetonitrile yields a soluble polyelectrolyte which may be thermally eliminated to give the electronically 'push-pull' substituted poly(2-cyano-5-methoxy-l,4-phenylene vinylene). Ultraviolet- visible and infra-red spectral studies showed production of the conjugated polymer, with a band gap of ca. 2.6-3.0 eV (410--480 nm) that varied somewhat as a function of elimination conditions. Elemental analysis indicates some retention of tetrahydrothiophenium side groups in the polyelectrolyte polymer, despite the use of a variety of elimination conditions. The retention of side chains in this synthesis is possibly due to a significant degree of irregularity in the positions of the cyano and methoxy substituents in the eliminated polymer, resulting from non-regioselectivity in this polymerization. This reaction demonstrates the potential in the Wessling process for polymerization of p-xylylenes that have electronically very asymmetric ('push-pull') substitution patterns.
Посилання на статтю:
Polymerization of 1,4-bis(tetrahydrothiopheniomethyl)- 2-cyano-5-methoxybenzene dibromide: synthesis of electronically " push-pull" substituted poly(p-phenylene vinylene)s / Paul M. Lahti* and Ananda Sarker // Polymer. – 1994. – Vol 35. – P. 1312-1316.