Research
Mechano-chemistry is an emerging field of chemistry. Reactions are driven not by thermal energy, electrons or photons but rather by mechanical strain, which can lower the activation energy that needs to be overcome for bond cleavage [1].
This strain can, for example, be applied in a ball mill, which we use to convert polymers to monomers in the solid phase. Instead of adding a catalyst as powder to the ball mill, we functionalize the grinding spheres directly [2-3]. This significantly improves performance. The catalyst is placed right where the energy input into the system is the highest, at the impact point of the spheres. In addition, this patented [4-5] surface activated mechano-catalyst (SAM cat) avoids difficulties in bringing the powder catalyst, polymer and grinding spheres together at the same location at the same time. We are currently upscaling this technology to the kg-scale.
We also found that cheap additives, like sand can act as radical initiators to promote depolymerization [6].
Ball movement in a shaker ball mill
Current research focusses on expanding to polylactic acid and polyamide depolymerization, as well as, fundamental understanding of mechanochemical chain cleavage [7] and development of kinetic models [8].
Watch to learn more about our research
Eye Opener Adrian Hergesell Tensioning plastic bonds for recycling - Adrian Hergesell- Ina Vollmer at the CMCC discussion series Summary of the Mechano-catalysis research
Science for Sustainability Reinventing the recycling of plastics
References
Open Science
We strive for full open science with full transparency of our analyses using python and open source data formats. We publish all data with the articles and are moving towards executable papers, which are jupyter notebooks that contain all python snippets necessary to analyze and plot the measured raw data. The jupyter notebooks are hosted on google collab, which allows to run the code without any downloads. Please find two examples below.