Biostability of polyurethanes. Study from the viewpoint of microphase separated structure

The materials design focused on biomedical applications involves the analysis under physiological simulated conditions because it is of prime importance the determination of life-time and reliability of these materials. The goal of this work were the study of the biostability of a series of segmented thermoplastic polyurethane elastomers (STPUE), containing PTHF and PCL blocks as soft segment (SS), by means of hydrolytic degradation tests for 3 years to determine the useful life-time. Physico-chemical and thermal properties were analyzed from the viewpoint of microdomain structure. The results suggested a reorganization in hard and soft segment ordered structure by means of a greater number of hydrogen bonds which contributed to phase separation and hence low-water uptake, being less susceptible to hydrolytic attack.