Branched glycidyl azide polymer (GAP) and glycidyl azide-ethylene oxide copolymer (GEC) have been prepared by a degradation process using different polyols in the synthesis reaction. The azido homopolymers and copolymers were characterized by gel permeation chromatography and viscometry techniques. Energetic polyurethanes were then obtained from the curing of branched glycidyl azide polymers and copolymers using isophorone diisocyanate as a curing agent. The polyurethanes were characterized using thermomechanical analysis and tensile testing. The polyurethane copolymers have generally a higher elongation at break and a lower glass transition temperature than their GAP homopolymer counterparts. The polyol reactant used in the synthesis of GAP and GEC had an effect on the mechanical properties of the polyurethanes obtained from these polymers.