Triggered enzymatic Degradation of 3D printable sustainable Composite materials to enable circular materials use

Plastics make an indispensable contribution to human progress in virtually every aspect of life, such as in modern medicine, where they have led to an unprecedented improvement in quality of life and life expectancy. However, this progress comes at a high cost in terms of the exploitation of fossil resources and environmental pollution. The use of renewable raw materials as a substitute for synthetic polymers plays a major role in the transition toward sustainable materials and environmentally friendly solutions. In some emerging fields, such as 3D printing via stereolithography, the use of both sustainable materials and composite materials is severely limited. Furthermore, the reprocessing and recycling of these materials involve significant difficulties and considerable effort. This project aims to explore possibilities for designing 3D-printable composite materials based on sustainable resources that can be degraded through “degradation on demand” triggered by the use of chemical and/or enzymatic agents and subsequently repurposed for further material use. Based on vinyl ester monomers—a class of substances similar to (meth)acrylates but with significantly lower toxicity and inherently cleavable groups—cellulose and chitin nanofibrils will be chemically and/or enzymatically modified to enable shaping via high-resolution 3D printing (stereolithography). By combining suitable monomers and modifications, the compatibility of the formulations is ensured, and by selecting appropriate reinforcing materials, mechanical performance is achieved that can compete with conventional synthetic 3D printing materials. At the end of their service life, the basic building blocks can be recovered through the cleavage of functional groups and reused, which dramatically reduces the amount of waste generated.