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The phosphorous-based flame retardant additives poly(m-phenylene methylphosphonate) (PMP) and resorcinol bis(diphenyl phosphate) (RDP) arereacted with bisphenol F and aniline-based benzoxazine (BF-a). DSC, rheological analysis, FT-IR, and soxhlet extraction reveal the covalent incorporation of both FR additives - initiating phenols in PMP structure as well as free phenols generated via transesterification reaction in the case of RDP. In contrast to PMP, RDP elongates the processing window but decreases the thermo-mechanical properties. Both additives increase the resistance in reactions against small flames with solely a phosphorous loadingof 0.3 wt%, resulting in a V-0 rating and an improvement in the OI value by upto 2% for RDP and 4% for PMP. Both FRs reduce the heat release rate but increase the smoke production and the smoke toxicity in the case of RDP.

Im Fokus dieser Arbeit steht die Erforschung und Entwicklung von thermisch stabilen Faser-Kunststoff-Verbunden (FKV) auf Basis von Polybenzoxazin und phosphorhaltigen Flammschutzmitteln sowie die dazugehörigen Fertigungs- und Fügeverfahren. Im Zuge dieser Arbeit wird ein Verständnis zum Einfluss von unterschiedlicher Einzelkomponenten und deren Wechselwirkungen sowie von unterschiedlichen Fertigungs- und Fügeverfahren auf die Verarbeitungs- und Materialeigenschaften aufgebaut. Durch eine modellhafte Beschreibung des Einflusses der Materialzusammensetzung und der Fertigungsverfahren auf die Verarbeitungs- und Materialeigenschaften sowie durch die Darstellung der komplexen Wechselwirkungen zwischen den mechanischen und Brandeigenschaften wird es in der Zukunft möglich sein, die Eigenschaften von polybenzoxazinbasierten FKV gezielt einzustellen.

For lightweight materials, e.g. aluminium, the definition of proper joining technology relies on material properties, as well as design and manufacturing aspects. Substrate thickness is especially relevant due to its impact on the weight of components. The present work compares the performance of adhesively bonded (AJ) to hybrid riveted-bonded joints(HJ) using aluminium substrates. To assess the lightweight potential of these joining methods, the effect of substrate thickness (2 and 3 mm) on the lap-shear strength (LSS) of single lap joints is investigated. An epoxy-based structural adhesive is employed for bonding, whilst HJs are produced by lockbolt rivet insertion into fully cured adhesive joints. The stiffness of joints increased with an increase of substrate thickness. HJs presented two-staged failure process with an increase in energy absorption and displacement at break. For HJs, the substrate thickness changed the failure mechanism of rivets: with thicker substrates failure occurred due to shear, whereas in thinner substrates due to rivet pulling-through. The LSS of 2mm and 3 mm-thick AJs is similar. With 2 mm-thick substrates, the LSS of HJs was lower than AJs. In contrast, the highest LSS is obtained by the 3 mm-thick HJs. The highest lightweight potential, i.e. LSS divided by weight, is achieved by the 2 mm-thick AJs, followed by the 3 mm-thick HJs with a loss of ca. 10% of specific LSS.