Effect of the hard segment chemistry and structure on the thermal and mechanical properties of novel biomedical segmented poly(esterurethanes).

摘要: Two series of biomedical segmented polyurethanes (SPU) based on poly(e-caprolactone) diol (PCL diol), 1,6-hexamethylene diisocyanate (HDI) or l-lysine methyl ester (LDI) and three novel chain extenders, were synthesized characterized. Chain extenders containing urea groups an aromatic amino-acid derivative incorporated in the SPU formulation to strengthen hard segment interactions through either bidentate hydrogen bonding π-stacking interactions, respectively. By varying composition (diisocyanate extender), its structure was varied investigate structure-property relationships. The different chemical symmetry modulated phase separation soft domains, as demonstrated by thermal behavior. Hard association more enhanced using a combination symmetric urea-diol extenders. cohesion had important effect observed mechanical Polyurethanes HDI (Series H) stronger than those obtained LDI L). latter exhibited no tendency undergo cold-drawing lowest ultimate properties. Incorporation extender produced opposite effects, resulting with highest elongation tearing energy strain at break Since biodegradable possess range properties, these materials may hold potential for use tissue engineering scaffold applications.