Heat-resistant thermoplastic polyurethane elastomer and preparation method thereof

The invention discloses a heat-resistant thermoplastic polyurethane elastomer and a preparation method thereof. The preparation method comprises the following steps of: dehydrating 55-80 parts of macromolecular dihydric alcohol, then adding the dehydrated macromolecular dihydric alcohol into TODI (Toluene Diisocyanate), reacting at the temperature of 75-120 DEG C to generate a prepolymer which has good storage stability and contains 3.0% to 9.0% of NCO; uniformly mixing 1.5-13 parts of chain extender, 0.001-0.1 part of catalyst, 0.05-1 part of oxidation inhibitor, 0.2-1 part of ultraviolet light absorbent and 0.2-2 parts of light stabilizer, and then mixing with the prepolymer in the step (a); vacuumizing and deforming the mixture in the step (b), and then pouring into a mould of 140-200 DEG C for demoulding for 10-25min; and curing the demoulded semi-finished products in a drying oven of 100-120 DEG C for 20-24 hours to obtain a finished product. The polyurethane elastomer has good high-temperature resistant property; the ratio of the storage modulus measured at 75 DEG C and 150 DEG C is less than 1.5; and the polyurethane elastomer has good integrated mechanical property and low cost.