Effect of Hard and Soft Segment on StructureProperty of Thermoplastic Polyurethane Elastomer

A series of polyurethane (PU) elastomers based on polybutylene adipate (PBA) as soft segment were synthesized by bulk polymerization and solution polymerization. Their morphologies, shapememory effect, thermal stability and mechanical properties were analyzed by means of FT-IR spectra, AFM, TGA, tensile tests and hydrolysis stability testing. Polytetramethylene glycol (PTMG) was added into soft segment to get better performance of the specimens. PU shows different performances by changing the mol ratio of MDI and BD (hard segment) and the quantity of polyether adding into the soft segment. Results show that better mechanical properties, water resistance and 75%-85% of shape recovery are obtained at 31%-35% of hard segment content and 4%-5% of PTMG content.