Solid-State Crosslinkable, Shape-Memory Polyesters Serving Tissue Engineering.

Acrylate-endcapped urethane-based precursors constituting a poly(D,L-lactide)/poly(ε-caprolactone) (PDLLA/PCL) random copolymer backbone were synthesized with linear and star-shaped architectures and various molar masses. It was shown that the glass transition and thus the actuation temperature could be tuned by varying the monomer content (0-8 wt% ε-caprolactone, T g,crosslinked = 10-42°C) in the polymers. The resulting polymers were analyzed for their physico-chemical properties and viscoelastic behavior (G' max = 9.6-750 kPa). The obtained polymers were subsequently crosslinked and their shape-memory properties were found to be excellent (R r = 88-100%, R f = 78-99.5%). Moreover, their potential towards processing via various additive manufacturing techniques (digital light processing (DLP), two-photon polymerization (2PP) and direct powder extrusion (DPE)) was evidenced with retention of their shape-memory effect. Additionally, all polymers were found to be biocompatible in direct contact in vitro cell assays using primary human foreskin fibroblasts (HFFs) through MTS assay (up to ∼100% metabolic activity relative to TCP) and live/dead staining (> 70% viability). This article is protected by copyright. All rights reserved.