Polyurethane polymers are a wide class of materials, ranging from surface coatings and adhesives to flexible or rigid foams. However, polyurethanes in general are very flammable and produce heavy smoke when burning. As a result of their flammability, there is a great interest in the development of materials with improved fire retardance. In this study a series of new ferrocene urethane block copolymers based on diphenylmethane-4,4'-diisocyanate were synthesized and their fire retardant behavior studied using thermogravimetric analysis (TGA), differential scanning calorimetry, cone calorimetry, and the oxygen index. Ferrocene-modified block copolyurethanes showed a 40-80% reduction in peak heat release rate compared to an unmodified sample. In addition, the TGA results showed that ferrocene-modified polymers have high thermal stability and ferrocene enhances char formation in air and helium. The synergistic effect of silicone and phosphorus with ferrocene was also discussed. The solution electrochemical behavior of ferrocene-containing polymers was studied using cyclic voltammetry. These polymers showed a reversible wave at E degrees approximate to 0.771-0.852 V and the electron transfer was diffusion controlled.