Polymer blends comprising a first phase comprising a thermoplastic polyurethane matrix and a second phase comprising a crosslinked polar olefin polymer are provided. The first phase is a continuous phase and the second phase can be co-continuous with the first phase, or dispersed as a non-continuous phase in the first phase. The first phase further comprises a metal hydroxide flame retardant and an organic flame retardant. The second phase further includes a metal hydroxide which is coupled to the olefin polymer via a silane coupling agent.