Dübendorf ZH – A laboratory at the Swiss Federal Laboratories for Materials Science and Technology (Empa) has developed an ultra-light, biodegradable and printable aerogel made of cellulose. It could be used in microelectronics for insulation, for slow drug delivery in the body and as an implant.
Researchers at Empa's Building Energy Materials and Components laboratory have succeeded in producing a cellulose-based, 3D-printable and biodegradable aerogel made of cellulose. According to a report by Empa, a "miracle material" has been created in collaboration with the Cellulose & Wood Materials and Advanced Analytical Technologies laboratories and the Center for X-ray Analysis.
It is sufficiently viscous to hold a three-dimensional shape before curing. At the same time, it liquefies briefly under pressure so that it can flow through the printer nozzle. "We were able to achieve the required properties with cellulose alone, without any additives or fillers," the group leader for functional aerogel materials, Shanyu Zhao, is quoted as saying.
To turn the ink into an aerogel after printing, the researchers first replace the water solvent in the pores with ethanol and then with air, without deforming the printed object, according to Empa. The high porosity makes the material an extremely effective heat insulator. It is also anisotropic, which means that its strength and thermal conductivity are direction-dependent. Such precisely insulating components could be used in microelectronics, for example.
The researchers also see great potential in medicine because this aerogel is biocompatible with living tissue. Its porous structure could absorb medication and release it over a longer period of time. Molds made from this material could serve as scaffolds for cell growth or as implants. In addition, the aerogel can be rehydrated and re-dried several times, which makes it much easier to store and use. ce/mm