Polyurethane is a general term for a class of polymers containing a carbamate group (-NHCOO-) in its main chain structure, including thermoplastic elastomers, flexible and rigid foams, and other species [1-2].The existence of thermodynamically incompatible soft segments and hard segments in the structure of polyurethane can cause microphase separation, which gives polyurethane some superior characteristics.Its performance can be adjusted by redesigning the proportion and the structure of soft and hard segments [3-5].Thus, since its advent in the 1960s, biomedical-grade polyurethane has become one of the most valuable biomedical materials owing to its good blood compatibility and biocompatibility, absence of distortions and allergic reactions, and excellent processability, toughness and elasticity [6-7].