The effect of molecular orientation on the conductivity of iodine intercalates of 1,4-trans-polybutadiene

Of three polybutadienes, 1,4-cis-PB, 1,2-syndio-PB and 1,4-tarns-PB, only the latter forms an intercalate with iodine. Maximum conductivity of 1,4-trans-PB/I2 is 0.9.102 cm 1 in ambient atmosphere. Intercalation in stretch-oriented samples, obtained via calendering or solid state coextrusion is impaired leading to markedly lower conductivities. The effect of enhanced molecular orientation with respect to conductivity is adverse. These results undermine a conclusion reached by A.J. Thakur in a study of iodine intercalates of polydienes, implying that a conjugated backbone is not a necessary prerequisite for an effective organic conductor.