A series of thermoplastic polyurethane elastomers (TPUs) with various hard-segment contents was prepared using 4,4’-diphenylmethane diisocyanate and 1,4-butanediol as the hard segment and poly(ethylene adipate)diol or poly(butylene adipate)diol, whose number-average molecular weight is 2000, as the soft segment. The miscibility of TPU/polycarbonate (PC) blends observed by differential scanning calorimetry was enhanced by the interchange reaction at high temperature. Both hard and soft segments were suggested to be involved in the interchange reaction with PC.