Plastic’s widespread negative reputation could soon be a thing of the past: Scientists at the Freiburg Materials Research Centre (FMF) at the University of Freiburg are developing what are known as pure composites, which can be produced from both fossil and renewable raw materials and later recycled without leaving residues. At the same time, researchers are working on producing new materials from waste products such as waste paper that can be used for 3D printing.
The scientists from Professor Dr. Rolf Mülhaupt’s research group in Freiburg will present their new materials at “K”, the world’s largest trade fair for plastics and rubber, to be held in Düsseldorf from 16 to 23 October 2019. According to the researchers, the special feature of these pure composites is that they are produced on the basis of hydrocarbon materials that reinforce themselves without the addition of foreign substances and are characterized by high strength, stiffness and impact resistance. “They can be used as raw material and energy sources and are also suitable for 3D printing,” says Timo Hees. His colleague Carl Schirmeister adds: “In future, composite materials could be useful in sustainable lightweight construction, in the manufacture of orthopedic aids such as orthoses, and in plastic gears.
Anne Asmacher and Benjamin Stolz also produce materials suitable for 3D printing from waste products such as waste paper and orange peel, in the laboratory more or less next door. For this the chemically untreated waste paper is first crushed and starch is added to create a paste that 3D printers can process. “By mineralizing with a silicate, the mechanical properties can be enhanced and the resistance to moisture and flammability increased,” says Benjamin Stolz. Due to its exceptionally low density, the material is particularly suitable for applications in lightweight construction. The weight savings could, for example, save fuel in the transport sector or in the aviation and automotive industries, which would have an additional positive effect on sustainability alongside the use of waste paper as a waste product.
Furthermore, the researchers have used limonene, a substance obtained from orange peels, to produce compounds with a low viscosity. “The advantage here is that they gain additional stiffness and temperature stability and are therefore suitable for additive toolmaking such as injection molds,” explains Asmacher.