Novel Superelastic Polyesters Based on 2,5-Furandicarboxylic Acid for Potential Use in Ophthalmic Surgery

The rapid development of ophthalmic surgery in recent years has made big steps forward, making interventions such as penetrating and lamellar keratoplasty or trabeculectomy widely practiced. However, the use of non-absorbable sutures in these procedures poses significant challenges. Indeed, unequal tension between the various stitches can lead to deformations of the cornea or lens and consequently to problems such as post-operative astigmatism or anisometropia. To overcome these problems, sutures with improved closure via a highly stretchable behaviour together with an excellent elastic return are a credible solution. Accordingly, to widen the plethora of superelastic polymeric materials, in the present study a novel solution deriving from two furan-based polyesters, poly(pentamethylene furanoate), PPeF, and poly(hexamethylene furanoate), PHF, was successfully obtained. Of note, these homopolymers are also entirely derived from sustainable sources. The two homopolymers were physically and chemically mixed to obtain copolymers with different block lengths, which were characterised from molecular, thermal, mechanical, and surface wettability points of view, showing interesting properties which were easily modulated as a function of block length. Lastly, all the materials showed good stability over time and cell viability and, for some of them, a great mechanical recovery upon deformation was also observed.