Biodegradable and biocompatible polyesters based on poly(butylene succinate) and poly(hexamethylene diglycolate) with shape memory features for potential use in corneal surgery

Nowadays, interventions in ophthalmic surgery, in particular corneal ones, are countless. Regardless of the type, the success of each intervention is largely due to the correct positioning and tightness of the suture. The achievement of these goals is particularly challenging, although extensive research has been carried out to design new materials with suitable features, including shape memory ones. Among all synthetic polymers, aliphatic polyesters are credible solutions for the realization of biocompatible sutures, as they are easy to process and show a very high degree of customization. Accordingly, in the present study, poly(butylene succinate) (PBS), a biocompatible and biodegradable aliphatic polyester, was chosen as the reference homopolymer. In order to lower its high rigidity and improve the low degradation rate, it was physically and chemically mixed with poly (hexamethylene diglycolate) (PHDG), another aliphatic polyester containing ether oxygens in its main chain. The new materials obtained showed intermediate properties, especially from a thermal and mechanical point of view, depending on the molecular architecture. The introduction of PHDG, in addition to not interfering with the biocompatibility of PBS, also allowed for an increase in its degradation rate. Last, but not least, the obtained materials showed qualitative shape memory features.