The industrial applications of benzoxazines are limited due to their high curing temperatures. This drawback can be overcome by more reactive precursor compared to conventional benzoxazines or by application of efficient initiators. We report the synthesis of a new resorcinol-based benzoxazine and its cationic polymerization with thermolatent super acids, namely organic sulfonium hexafluoroantimonates. This combination of a reactive precursor and an efficient initiator results in a curing temperature below 100 °C (differential scanning calorimetry onset) which is up to now one of the lowest polymerization temperatures for benzoxazine systems. Furthermore, the thermal stability of the formed polybenzoxazine has not been influenced by the applied initiators

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Morphing concepts were investigated for a wingtip with active trailing edge (WATE) in an adaptive wing. The basic functionality is to take up geometric gap changes in order to maintain a smooth transition between connected parts. A specific material was tailored in order to meet a set of initially formulated requirements, which involve low modulus, high fatigue life, and stability against physical aging in a temperature range from −55 to +80 °C. A variety of material samples and joints were prepared and tested in order to provide a database for numerical simulation and sizing. One of the proposed solutions was developed until the physical sub-component level. Finally, morphing parts were prepared and delivered for assembly in ground test and true-scale wind tunnel demonstrators