Figure 4 - uploaded by Bernhard von Vacano
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Value chain and life cycle of polymers. Design targets for performance, safety, cost efficiency, and scalability in use phase as well as for end of life (EoL) are indicated by dashed orange arrows. Circular loops can be established via the biosphere (green arrow), technical loops in reuse and recycling (light blue arrows), or in an "open loop" via carbon capture and utilization (CCU, gray arrows).
Source publication
To achieve a sustainable circular economy, polymers need to start transitioning to recycled and biobased feedstock and accomplish CO2 emission neutrality. This is not only true for structural polymers, such as in packaging or engineering applications, but also for functional polymers in liquid formulations, such as adhesives, lubricants, thickeners...
Contexts in source publication
Context 1
... The reason for using a chemical, or specifically a polymer, is due to its function and valuable properties in the application ( Figure 1, Figure 2). Innovation along the chain for sustainable polymer design (Figure 4) starts (i) with a need for the specific performance in use, including cost/ performance metrics and scalability, and at the same time (ii) must embrace safety, sustainability, and intrinsically a circular end-of-life (EoL). For polymer synthesis, a variety of monomers can be chosen from fossil or renewable feedstocks, including biomass and recycled feedstock or obtained from carbon capture and utilization (CCU). ...
Context 2
... examples above show how the capabilities of the polymer can directly impact the circularity of the system and product they are employed in. There is, however, a reverse relationship, too; the design of the system (Figure 14) must be such that it allows the polymer to shine. For many recycling technologies, heterogeneity of waste streams is a big hurdle that prohibits certain pathways or severely limits the achievable result. ...
Citations
Dye-decolorizing Peroxidases (DyPs) are heme-containing enzymes in fungi and bacteria that catalyze the reduction of hydrogen peroxide to water with concomitant oxidation of various substrates, including anthraquinone dyes, lignin-related phenolic and non-phenolic compounds, and metal ions. Investigation of DyPs has shed new light on peroxidases, one of the most extensively studied families of oxidoreductases; still, details of their microbial physiological role and catalytic mechanisms remain to be fully disclosed. They display a distinctive ferredoxin-like fold encompassing anti-parallel β-sheets and α-helices, and long conserved loops surround the heme pocket with a role in catalysis and stability. A tunnel routes H2O2 to the heme pocket, whereas binding sites for the reducing substrates are in cavities near the heme or close to distal aromatic residues at the surface. Variations in reactions, the role of catalytic residues, and mechanisms were observed among different classes of DyP. They were hypothetically related to the presence or absence of distal H2O molecules in the heme pocket. The engineering of DyPs for improved properties directed their biotechnological applications, primarily centered on treating textile effluents and degradation of other hazardous pollutants, to fields such as biosensors and valorization of lignin, the most abundant renewable aromatic polymer. In this review, we track recent research contributions that furthered our understanding of the activity, stability, and structural properties of DyPs and their biotechnological applications. Overall, the study of DyP-type peroxidases has significant implications for environmental sustainability and the development of new bio-based products and materials with improved end-of-life options via biodegradation and chemical recyclability, fostering the transition to a sustainable bio-based industry in the circular economy realm.
