Dielectric elastomer actuators (DEA) are special devices which have a simple working and construction principle and outstanding actuation properties. The DEAs consist of a combination of different materials for the dielectric and electrode layers. The combination of these layers causes incompatibilities in their interconnections. Dramatic differences in the mechanical properties and bad adhesion of the layers are the principal causes for the reduction of the actuation displacement and strong reduction of lifetime. Common DEAs achieve actuation displacements of 2% and a durability of some million cycles. The following investigations represent a new approach to solving the problems of common systems. The investigated DEA consists of only one basic raw polymer, which was modified according to the required demands of each layer. The basic raw polymer was modified with single-walled carbon nanotubes or high-k ceramics, for example, lead magnesium niobate-lead titanate. The development of the full polymer DEA comprised the development of materials and technologies to realise a reproducible layer composition. It was proven that the full polymer actuator worked according to the theoretical rules. The investigated system achieved actuation displacements above 20% regarding thickness, outstanding interconnections at each layer without any failures, and durability above 3 million cycles without any indication of an impending malfunction.

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Summary Efficient production of carbon fibres using new technologies Innovative process technologies for carbonization of precursor fibres, which can substitute conventional oven technologies and raise the efficiency of carbon fibre production are presented. The process technologies are based on the substitution of convective heat transfer by microwave plasma or direct fiber heating. In microwave‐assisted plasma treatment, the heating of the fibres is carried out both by microwave absorption in the fibre volume and energy input into the fibre surface by means of the plasma species. During electrical carbonization, the fibres are heated by means of an electrical current flow. The processes can be used separately, one after the other (also in combination with conventional furnace technology) or as hybrid processes.