Well–defined polyesters for applications in life science

This work of thesis describes the preparation of polyester-based materials of interest for applications in biomedical field. Starting from the polymerization design, varied catalytic systems and monomers were selected to access novel materials. Representing a healthier alternative to heavy metal complexes often employed in industry, strontium isopropoxide was employed for the first time as a catalyst for the polymerization of L–lactide and a selection of lactones, proving a high activity and an excellent molar mass already at room temperature. The selection of suitable catalysts was furthermore complemented with the development of copolymers with the same Hydrophilic Hydrophobic Balance (HHB) of poly(lactic acid) or poly(caprolactone). As a result, new polyesters with similar molar mass featuring a controlled variation of thermal properties were prepared and used for the preparation of stable nanoparticle suspensions with similar size. This study enabled to prove: (a) The direct relationship between the bulk thermal properties and the nanoparticle stiffness; (b) the role of synthetic design for both the controlled variation of polyesters properties and for the preparation of tailor-made PLA stereocomplexes; and (c) the experimental proof on how polyester design allow the preparation of nanoparticles with constant HHB.