The invention provides a conductivity control agent comprised of a polymeric material containing diphosphonium bis(sulfoarylcarbonyloxy) glycol salts as conductivity control agent. The conductivity control agents can be used with semi-conductive rolls, belts and other biasable members. The inclusion of the conductivity control agent in the polymeric or polyurethane elastomers extends the electrical life of the polymeric biasable member in low humidity environments. Additionally, the resistivity of the elastomeric polymer on the biasable member is controlled to a desirable value by adjusting the conductivity control agent level in the elastomers.