Synthesis of Novel Chain Extended and Crosslinked Polylactones for Tissue Regeneration and Controlled Release Applications

Abstract

In addition to ring opening homo- and co-polymerization, chain extension and crosslinking are attractive routes for synthesizing polylactones. Through manipulation of molecular composition and molecular architecture a wide range of mechanical, thermal and degradation properties can be achieved, and using different coupling chemistries, polylactones belonging to many kinds of linear and network-structured polymer families have been synthesized. The poly(ester-urethanes), poly(ester-amides), poly(ester-urethane-amides), polyphosphoesters, poly(ester-anhydrides) and methacrylated crosslinking polyesters polymer families have great potential in biomedical applications such as surgery, tissue-engineering, and controlled active agent release. Mechanical properties, degradation characteristics and rate, and release properties of these polymers can be adjusted within wide ranges. Biopolymers showing bone-like hardness or soft non-creeping elasticity have been synthesized. Poly(ester-anhydrides) in particular combine useful properties of polyesters and polyanhydrides, and have been shown to degrade by surface-erosion, enabling controlled macromolecular active agent release. Photocuring of liquid pre-polymers enables the use of biopolymers in high precision lithographic techniques like micromolding in capillaries, stereolithography and two-photon polymerization. This makes it possible to design and customize complicated scaffold structures, with desired drug release profiles for various biomedical applications.