Double polymer networks consist of two independently cross-linked, water-filled polymer networks that are topologically interlocked. A mechanical synergism between the two networks gives such double network hydrogels an exceptional toughness, which makes them very interesting for use in biomedical applications. However, covalently cross-linked double networks have the draw-back that they cannot recover from suffered damage and that, once prepared, the materials are fixed and hard to process. The aim of this proposal is to develop and study a new class of double polymer network hydrogels, based on physical rather than chemical cross-links. Because physical bonds can form and break reversibly in response to external triggers, such physically cross-linked double networks will be responsive and self-healing, producing materials that are not only tough, but also smart. Physical double polymer networks will be formed by simply (but judiciously!) mixing two different self-assembling triblock copolymers in aqueous solution. Each triblock copolymer consists of a water-soluble middle part and two associating end groups, chosen such that they do not form mixed assemblies. By choosing associating groups that can be triggered selectively (for example by a change in pH, temperature, or a chemical signal), we obtain dual-responsive materials, with visco-elastic properties that can be tuned from very soft to very stiff. In this proposal the focus is on understanding the relation between the microscopic properties of the two networks (architecture, cross-link dynamics, and tendency to phase-separate) and the resulting macroscopic structure and (synergistic) rheological properties. To do this, I will combine experimental work on well-characterized triblock copolymers (microscopy, scattering and rheology) with molecular theory and coarse-grained simulations.

While chemical pesticides are crucial to protect our crops, their usage comes with negative consequences: human poisoning, habitat destruction, and biodiversity loss. Our continued dependence on harmful pesticides has far reaching consequences, here in the Netherlands, and globally with seemingly few chemical alternatives. The natural defense strategies of plants include both chemical and physical mechanisms. In glandular trichomes, these come together. Trichomes are hairy leaf structures that both secrete metabolites and can physically immobilize small harmful insects. Inspired by nature, we will develop a completely new, environmentally friendly strategy for plant protection. We will use an interdisciplinary approach to mimic glandular trichomes with adhesive spheres that are edible, non-toxic, renewable, cost-effective, and capable of immobilizing herbivories and secreting volatiles which are either repellant to herbivories or attractive to their natural enemies. Additionally, we will directly assess this strategy in field trials for efficacy on the target pest, non-target organisms, and the application methodology. By incorporating volatile compounds that mediate the communication in multithropic systems of plants, herbivores and their natural enemies, our strategy will combine both natural mechanisms found in plants. Linseed oil is an excellent first candidate for a promising material as it has low cost and negligible negative effects on the environment and human health. In preliminary trials we were able to deliver sticky spheres on leaves that showed reduced leaf damage by thrips compared to untreated leaves. The fundamental research of this project, conducted in collaboration with world-leading companies in plant protection products will pave the way for an innovative, sustainable way of plant protection by combining bioinspired volatile and physical defense mechanisms. Several partners will be directly involved in the research, which will ensure fast industrial implementation of sustainable and cost-effective technology we aim to deliver.

Many criminal cases, that affect people financially and emotionally, remain unsolved, because current analysis is not providing enough intelligence. In this project we aim to develop two different tools to enhance the effectivity and efficiency of crime scene investigation. First one is an innovative rapid test to determine whether a trace sample contains sufficient DNA that enables suspect identification. Second tool is a microfluidic device to establish at the crime scene if biological traces belong to the same individual (victim/suspect). With this we aim to increase the trust and confidence of citizens in government and law enforcing agencies.

NanoNu-Marker will undertake the scientific and societal challenge to develop, combine and apply innovative experimental and digital technologies to identify novel biomarkers at the nanoscale of cognitive decline, and to unravel the molecular links between protein aggregation and human nutrition/lifestyle, in order to tackle the socioeconomic impact of dementia and neurodegeneration on world ageing population.