The growing demand for functional materials in recent years has driven the search for new resources and the adoption of efficient, sustainable, and circular approaches in chemistry.¹ This shift is crucial for addressing environmental concerns, reducing dependence on fossil-based feedstocks, and improving process efficiency. To tackle these challenges, innovative strategies must be developed to not only enable the synthesis of high-performance polymeric materials but also adhere to the principles of green and circular chemistry—minimizing waste, lowering energy consumption, and promoting recyclability.
This lecture will explore the design and discovery of novel transformations utilizing both renewable² and petroleum-derived feedstocks to develop tailor-made functional polymeric mate-rials with advanced properties.³ Particular emphasis will be placed on the versatility of both established and emerging (multi-component) reactions, as well as photo-induced processes, which provide efficient and sustainable pathways for polymer synthesis.
Finally, we will confront a fundamental question: Are our current efforts enough to achieve a truly circular polymer economy? If so, what challenges still lie ahead?

The increasing number of infections caused by multidrug-resistant bacteria is now considered a critical global healthcare issue. To overcome this, antimicrobial peptides (AMPs) and mimics thereof have emerged as promising candidates as potential new antimicrobial drugs given their ability to kill bacteria with minimal resistance development. Unlike traditional antibiotics that act on intracellular targets, this class of compounds, which contain cationic (amines) and hydrophobic groups, exert their activity by perturbing the bacteria cell membrane, thereby making it harder for the bacteria to resist and develop resistance. However, this class of compounds also tend to exhibit toxicity toward mammalian cells (and thus poor selectivity), hence hindering their application in clinical settings. The main reason for this poor selectivity is due to the non-specific interaction/binding between the cationic groups of the antimicrobial agent with cell membranes.

To overcome this selectivity issue, our group have been developing novel AMP mimics wherein the cationic amines are initially caged like a prodrug (hence benign and safe) and only to be activated/uncaged using specific immolative chemistries in the presence of bacteria. This approach termed as the amine uncaging strategy (AUS), focusses on the precise activation of antimicrobial activity through the strategic uncaging of cationic amine groups with the overall goal of improving the biocompatibility of this class of compound. Thus far, we have investigated several systems based on external (photo), bio (enzymes) and chemical (click) activations, which will be highlighted in this talk.

We present a rapid method for screening large polymer libraries to design polymers for the non-covalent encapsulation of proteins and enzymes. Such “single protein/enzyme polymer nanoparticles”(1) can give control over the enzyme activity and prolong the stability of the protein, but designing the right polymer for a given protein from first principles is challenging because the polymer sequence must closely complement the surface of the target protein.
By automating the polymer synthesis using oxygen tolerant controlled radical polymerisation techniques such as enz-RAFT,(2) libraries containing a wide range of different charged, hydrophilic and hydrophobic monomers can be rapidly prepared. The binding affinity of these polymers toward the protein of choice is then screened by utilising the Förster Resonance Energy Transfer (FRET). Because the readout is very sensitive, the technique can be applied in low volumes and at low protein/enzyme concentrations.(3)
Careful design of the polymer composition not only permits adjustment of the binding affinity but also modification of the polymer’s properties such as, e.g. thermoresponsive behaviour. This can be utilised to selectively release the protein/enzyme which is desired in applications such as enzymatic decomposition of plastic materials.(4)

Modern devices, such as medical prostheses and data storage systems, often require the integration of multiple material properties. Traditionally, fabricating such components involves combining separately manufactured single-property parts using various engineering and manufacturing techniques. As a result, achieving true multi-material printing from a single vat has become a central focus in light-based 3D printing.
Techniques such as greyscale lithography (varying light intensity) and multi-wavelength printing (using different light colors) have enabled the tuning of material stiffness within a single resin by adjusting crosslinking density through controlled monomer conversion. However, these property differences tend to diminish over time due to post-curing from residual unreacted monomers, and the range of achievable material properties has largely been limited to soft versus stiff.
This talk presents advancements in greyscale lithography that extend beyond current limitations. It will highlight the fabrication of microscale objects with finely tunable mechanical properties and the integration of both degradable and non-degradable regions within a single 3D-printed structure.
Additionally, new strategies for one-photon vat photopolymerization enabling multi-material printing of macroscopic objects will be discussed. A key innovation is the effective trapping of crystallinity in photopolymers, allowing for precise control of transparency and thermomechanical behavior. This is achieved through adjustments in printing temperature or light intensity, introducing new capabilities for tailoring material properties during the printing process. These developments mark a significant step toward versatile, functionally complex 3D-printed components from a single resin system.