Cold resistant properties of high modulus polyurethane

Six kinds of polyurethane (PU) elastomers were prepared based on different polyesters, polyethers and chain extenders. The structure, mechanical properties and cold resistant properties of PU were systematically investigated by FTIR, XRD, DMTA, universal testing machine and flex ductility machine. The results show that T _g of soft segment is the main factor of the cold resistant properties of polyurethane elastomer. Compared with the same relative molecular mass of the polyester and the polyether, the polyether flexibility is better, the glass transition temperature (T _g) is lower and the cold resistant properties is remarkable, for example the cold resistant properties of PU based on poly (tetramethylene glycol), 1, 4-BG and MDI achieves the fifth level. The physics performances of polyurethane elastomers, such as breakdown strength, Young’s modulus and the cold resistant properties, are all superior.