Toughness enhancers for bone scaffold materials based on biocompatible photopolymers

Abstract

Providing access to the benefits of additive manufacturing technologies in tissue engineering, vinyl esters recently came into view as appropriate replacements for (meth)acrylates as precursors for photopolymers. Their low cytotoxicity and good biocompatibility as well as favorable degradation behavior are their main assets. Suffering from rather poor mechanical properties, particularly in terms of toughness, several improvements have been made over the last years. Especially, thiol–ene chemistry has been investigated to overcome those shortcomings. In this study, we focused on additional means to further improve the toughness of an already established biocompatible vinyl ester-thiol formulation, eligible for digital light processing-based stereolithography. All molecules were based on poly(ε-caprolactone) as building block and the formulations were tested regarding their reactivity and the resulting mechanical properties. They all performed well as toughness enhancer, ultimately doubling the impact resistance of the reference system.