Fibers belong to the most important class of materials with whom we are in close contact in daily life. Fibers are used in clothing, as medical products and for numerous technical applications, typically requiring a specific functionality.
Functionalization of fibers can be obtained by adding the envisaged functionality during compounding, spinning or subsequently by coating. The latter can be performed in reel-to-reel processes both on the fiber level as also with fabrics. At Empa, appropriate pilot-scale apparatus are available regarding more conventional wet-chemical treatment, overjacketing as well as advanced dry processing based on plasma technology.
Functional fibers for the life science field should not only pose any risks for health, but might bear further functional properties. Especially for the use in personalized medicine, controlled drug delivery is of high interest. The delivery can be triggered by external parameters like changes in temperature, pH, light intensity or in response to a physiological redox reaction. Furthermore, the development of sensors on the fiber level that are wearable, flexible and compatible with organic matter is a major research topic.
An increasingly large field for the use of fibers concerns fiber-reinforced composites. Most of all, high tenacity fibers lack functional groups at their surface affecting fiber/matrix adhesion. In particular, the deposition of functional plasma coatings enables the functionalization of such fibers without interfering with the fiber bulk properties. Thus, improved mechanical properties can be achieved both in fiber direction (longitudinal) as also perpendicular to the fibers (transversal) by minimizing voids and enhancing fiber/matrix strength. Furthermore, overjacketing by extrusion is investigated to obtain novel, fully thermoplastic prepreg materials. Here you will find more information about structured fibers ...