Carbon fiber composites are preferred in transportation sector due to their high specific strength, modulus and resistance to corrosive environments. This paper reports on usage of Polyamide 6 in automobile exterior components by adding 30 % PP, PP-g-MA (Polypropylene-grafted-Maleic anhydride) as a compatibilizer and Short Carbon fibers (SCF) as reinforcement. The effect of compatibilizer on the tensile and impact properties of the composites has been studied. Composite with 3 phr PP-g-MA and 5 wt% SCF revealed highest tensile strength and only 10 % reduction in its value due to water saturation. Microstructure analysis and Grey relational analysis confirmed the experimental results.

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Samples of lyocell fibres were taken in the form of filaments from fibre tow of potentially infinite length and in their final condition of staple fibres. Mechanical testing showed comparable tensile strength, but a 50% lower modulus of elasticity for staple fibres and a higher elongation at break compared to filaments from fibre tow. Structural investigation by means of synchrotron wide angle X-ray scattering and birefringence measurement revealed a significantly lower degree of preferred orientation together with less fibre straightness for staple fibres than for filaments. It is concluded that plastic deformation during the processing of staple fibres from filaments induces permanent changes in the orientation of cellulose chains in the fibres, which in turn is responsible for the observed differences in mechanical performance.

The white rot fungus Physisporinus vitreus is currently tested for several biotechnological applications such as permeability improvement of refractory wood species or the optimization of the acoustic properties of wood for violins. The enzymatic activity of P. vitreus results in the degradation of pit membranes and simultaneous alterations of the tracheid cell wall structure in wood of Norway spruce wPicea abies (L.) Karstx. By this means, selective delignification and simultaneous degradation occur in the latewood tracheids at short incubation times. To study the delignification of individual cell wall layers in latewood tracheids, cellular UVmicrospectrophotometry was applied to wood of Norway spruce that had been incubated for between 3 and 9 weeks. By means of this technique, the progressing delignification was demonstrated in the latewood tracheid secondary walls. Moreover, local delignification in close proximity to hyphal tunneling, cavities, and notches was evident. Additionally, the mechanical changes were measured (a) at the macroscopic level by Brinell hardness test and (b) at the cellular level by nanoindentation. Brinell hardness was significantly reduced with increasing incubation time which was attributed to the partial delignification. Unlike Brinell tests, results from nanoindentation tests did not show a clear effect of fungal activity because of the material heterogeneity and the high spatial resolution of this technique. The present study provides methodological approaches for the investigation of wood-fungus interactions and contributes to a better understanding of the characteristics of wood decay at the subcellular level caused by the white rot fungus P. vitreus. Moreover, it establishes the basis for a subsequent chemical analysis, for which the results will be the topic of a second paper in this series.