SOLUBLE CONDUCTING POLYMERS FROM POLYISOPRENE

Recently, 1,4-polyisoprene has been reported to be a prototype of electrically conducting polymers having non-conjugated backbones. In this paper we demonstrate for the first time that 'I2-doping' of 1,4-polyisoprene yields soluble conjugated conducting polymers through double bond shifting reactions. These reactions, in both solution and the solid state, are described. The formation of conjugated sequences of unsaturated double bonds in the polyisoprene backbone is followed by ultraviolet/visible and magnetic resonance spectroscopy. The sequences are stable and, resembling polyacetylene, they are probably responsible for the high conductivity of '12-doped' polyisoprene.