Thermoplastic polyurethane lightweight tire support

A lightweight tire support, comprising: a hard-segment polymer comprising a reaction product of an at least one first isocyanate and an at least one chain extender; a soft-segment polymer comprising a reaction product of a second isocyanate and an at least one polyol, said at least one second isocyanate being the same as or different from said at least one first isocyanate; and said hard-segment polymer and said soft-segment polymer being present in an amount effective for providing said tire support with load-bearing capability and temperature stability. The poiymer is a microcellular polymer having a density of iess than 1 g/cc. The tire support has temperature stability and load-bearing capability.