PhD opening: Naturally sourced double network granular hydrogels
Direct ink writing (DIW)-based 3D printing allows to vary the composition of materials, such as hydrogels and elastomers in all three dimensions with spatial resolutions of order 100 µm. However, only inks that fulfill certain rheological requirements can be 3D printed through DIW. Inks composed of jammed hydrogel, or elastomer based microparticles can readily be 3D printed through DIW. The resulting granular hydrogels are typically rather soft. My group introduced double network granular hydrogels and elastomers that are sufficiently stiff to lift loads up to 250 times their own weight. However, thus far, we almost exclusively formulated double network granular hydrogels from non-renewable precursors. The goal of this PhD project is to introduce naturally sourced double network granular hydrogels whose mechanical properties can be tuned over a wide range. You will formulate naturally sourced double network granular hydrogels and characterize their mechanical properties as a function of their composition and microstructure. In the second part of this PhD thesis, you will introduce responsiveness into these 3D pintable, load-bearing hydrogels. We intend to use these naturally sourced hydrogels for example, for biomedical applications and in soft robotics.
PhD opening: Recyclable double network granular polymers
Granular hydrogels and elastomers are well suited for recycling because they do not have to be decomposed to the molecular level but can be disassembled into microparticles that can be recycled. While the disassembly of granular materials into microparticles can be readily performed on soft granular hydrogels, it is more difficult to do if granular systems are reinforced to impart them load-bearing properties. Yet, load-bearing properties are crucial if these materials are used, for example, in soft robotics or for certain biomedical applications. This PhD thesis is devoted to introduce an efficient recycling strategy for load-bearing double network granular hydrogels and elastomers. Within this thesis, you will introduce dynamic covalent bonds into granular double network hydrogels and elastomers and study their influence on the mechanical properties of these systems. You will establish protocols do disassemble these systems into individual microparticles that can be recycled into new materials possessing tunable mechanical properties and optionally additional functionalities. You will study the influence of the composition and microstructure on the recyclability and mechanical properties of these granular systems.
PhD opening: Biomineralization of double network granular hydrogels
Nature often fabricates minerals that exhibit a fascinating combination of stiffness and toughness. In many cases, this is achieved by mineralizing well-defined organic scaffolds. Inspired by nature, this PhD project aims at mineralizing double network granular hydrogels to stiffen them. Within this project, you will establish formulations that enable a controlled mineralization of granular hydrogels. You will systematically study the influence of the scaffold composition, structure, and dimensions and mineralization conditions on the degree of mineralization, the location of the forming minerals and their structure and relate these parameters to the mechanical properties of the granular composite. In the second part of the PhD thesis, you will exploit the rheological properties of the granular precursors to 3D print scaffolds into cm-sized substrates that will be mineralized with the ultimate goal to test their biocompatibility in vitro and if positive and in collaboration with other labs in vivo.
We are looking for a highly motivated candidate that likes working in an interdisciplinary environment on a challenging project. A successful candidate should have a background in material science, chemistry, chemical engineering, physical chemistry, nanotechnology or related subjects.
If you are interested, please send a CV and a motivation letter to [email protected].