uni'wissen 02(4)-2011_ENG

used to produce cups, bags, and films that are partially biodegradable. However, the materials Samyn plans to produce will provide better pro- tection against certain substances than their predecessors and should ultimately be com- pletely compostable. The junior professor can control what a coating does and allows or doesn’t allow by varying the type of nanoparticle used for it: If steam were allowed to escape from the car- ton, the pizza wouldn’t have the consistency of a damp rag upon delivery, and paper cups would retain their form better when hot coffee is poured into them. In the future it will even be possible to equip packages like milk cartons and yoghurt containers with chemical sensors that change color to warn consumers that the content is spoiled. Wood as a Source of Inspiration Samyn is also conscious of the potential dan- gers of nanotechnology. “Our products won’t emit any individual particles,” he says. “Each of them will be processed in a fluid substance and embedded firmly in the biopolymer matrix.” Even if the coating breaks, the microscopic particles will remain in them. In addition, Samyn is devel- oping new processes to enable the coating to close itself again if it does break. In particular cases, it would also be possible to cover the coating with another coating made exclusively of polymers in order to prevent the nanoparticles Nanoparticles give materials new properties: The little bubbles cover up the cellulose fiber, which runs from the bottom to the top of the picture, and make it water-resistant. Junior Professor Dr. Pieter Samyn was born in Belgium in 1978. He studied materials engineering at the Univer- sity of Ghent, where he completed his dissertation on mechanical phenomena in friction between plastics in 2007. He then came to the Department of Micro- systems Engineering in Freiburg, where he con- ducted research into chem- ical aspects of adhesion phenomena until 2008. Af- ter an interlude in Belgium, he returned to Freiburg in October 2010 to head a re- search group under Prof. Dr. Marie-Pierre Laborie at the Institute of Forest Utili- zation and Work Science. In March 2011 he accepted the Robert Bosch Profes- sorship for the Sustainable Use of Natural Resources. Further Reading Samyn, P./Deconinck, M./Schoukens, G./ Stanssens, D./Vonck, L./Van den Abbeele, H. (2011): Synthesis and characterization of ­imidized poly(styrene-maleic anhydride) organic nanoparticles in stable aqueous dispersion. In: Polymers for Advanced Technologies (in press). Samyn, P./Schoukens, G./Vonck, L./ ­Stanssens, D./Van den Abbeele, H. (2011): How thermal curing of an organic paper ­coating changes topography, chemistry and wettability. In: Langmuir 27/13, p. 8509 – 8521. Samyn, P./Van Erps, J./Thienpont, H./ Schoukens, G. (2011): Paper coatings with multi-scale roughness evaluated at different sampling sizes. In: Applied Surface Science 257/13, p. 5613 – 5625. from coming into contact with foods. “We are keeping tabs on potential risks and safety in our laboratory work, but we need to grasp the oppor- tunity the properties of this new class of materi- als present.” However, first he will need to conduct re- search in order to find the ideal mix of coatings from cellulose particles, protective particles, and biopolymers. “The goal is to achieve as much functionality as possible with the thinnest possi- ble coating and the lowest possible proportion of nanoparticles,” explains Samyn. This will involve determining which plants can be used to pro- duce the best whiskers, since they can differ in form, reactivity, and the length of their chemical cellulose chains. The end product must be a ho- mogeneous coating that is easy to work with. Sa- myn is using the natural composition of wood as a source of inspiration to combine the compo- nents in a new way. “In the best case we will be able to use the wood fiber lignin, the largest component of black liquor, as a biopolymer ma- trix.” So there is enough to research, to test, to experiment with. Being able to work on this proj- ect without financial worries for the coming five years is a solid basis for achieving these goals, as Samyn finds. For the future, he hopes to con- tribute to creating a world in which supermarkets and fast food restaurants only use sustainable packaging and bags: “It’s time to close the cycle between earth, plant, and product.” 27uni'wissen 04