Polyhedral Oligomeric Silsesquioxane (POSS)-Based Hybrid Nanostructured Thermoplastic Polyurethanes (TPUs) ---- Synthesis, Processing and Biomedical Applications

摘要

Polyhedral Oligomeric Silsesquioxane (POSS) is a class of well-defined, highly symmetric molecules that contain an inner inorganic framework made up of silicone and oxygen (SiO1.5)x and externally covered by eight organic substitutes. The hybrid organic-inorganic framework renders POSS thermally and chemically robust nature, and the eight vertex R-groups feature the versatility in chemistry. In a subtle way, nano-scale POSS moieties were introduced into conventional thermoplastic polyurethanes(TPUs) to form a new generation of hybrid TPUs nano-composites. By tailoring the biocompatible soft segments (e.g. poly(ethylene glycol)(PEG), poly(caprolactone)(PCL), poly(d,l-lactide)[P(d,l)-LA], etc), we have developed a series of novel hybrid POSS-TPUs with a wide variety of biomedical applications, including mechanical robust hydrogels, nano-structural antimicrobial hydrogel webs with long-term duration, enzymatic biostable polyester-based hybrid TPUs for long-term biomedical implantation, hybrid TPUs with high-drug (i.e. Paclitaxel) loading and tailored drug release for biodegradable stent coating, among others.