This work explores the synthesis and strategic design of bio-based materials derived from renewable terpene monomers. The overarching objective is to develop a comprehensive framework encompassing the establishment of efficient monomer synthesis, the polymerization of sustainable bio-PAs, and the adaptation of polymer properties through copolymerization and strategic functionalization. Particular emphasis is placed on investigating potential biomedical applications.
The research begins by identifying the terpenes, limonene, and β-pinene as abundant and structurally advantageous starting materials for lactam modification and subsequent polymerization. Efficient synthesis routes for their respective lactams are established and optimized, meeting industrial scalability and applicability. The unique structural features of these monomers, such as the bicyclic nature of β-pinene and the exo-cyclic double bond in limonene, hold the promise to impart stability or functionalizability into the resulting polymers. Anionic ring-opening polymerization (AROP) is employed for the controlled synthesis of high molecular weight limonene polyamide (LiPA) and β-pinene polyamide (PiPA). Challenges posed by steric hindrance and side reactions are addressed through the judicious selection of initiators and activators. Upscaling to gram quantities is achieved, enabling thorough material characterization and processing. The resulting PiPAs exhibit excellent thermal stability, good mechanical properties, and transparent appearance, while LiPAs possess not only good thermal stability but also functionalizability, rendering both PAs promising for high-performance/bio-applications.
To combine the strengths of PAs, e.g. high thermal and mechanical stability, and the strengths of polyesters, e.g. biocompatibility, ring-opening copolymerization (ROCOP) of β-pinene lactam and ε-caprolactone is investigated, yielding polyesteramides (PEAs) with tunable properties, such as solubility and brittleness, and high thermal stability.
Recognizing the potential of LiPA for biomedical applications, thiol-ene click chemistry is employed to introduce various functional groups, including alkyl, ester, and sulfonate moieties. This strategic modification enables the tuning of glass transition temperature, solubility, hydrophilicity, and even the formation of amphiphilic micelles for potential drug delivery applications. The high tolerance of the thiol-ene reaction towards diverse functional groups opens avenues for future incorporation of bioactive moieties, such as cell-binding motifs for tissue engineering.
While the findings are highly promising, further investigations are necessary to address challenges like poor solubility, processability, and evaluating specific biomedical applications through cell tests. Nevertheless, this thesis contributes significantly to the field of sustainable materials science by introducing novel monomers, polymers, and a versatile functionalization approach, ultimately paving the way for innovative and environmentally conscious solutions in biomedicine and beyond.
«
This work explores the synthesis and strategic design of bio-based materials derived from renewable terpene monomers. The overarching objective is to develop a comprehensive framework encompassing the establishment of efficient monomer synthesis, the polymerization of sustainable bio-PAs, and the adaptation of polymer properties through copolymerization and strategic functionalization. Particular emphasis is placed on investigating potential biomedical applications.
The research begins by ide...
»