Application of Partial Wave Crossing Relations to πN Scattering

The partial wave crossing relations derived in a recent paper by Steiner [1] are used for a calculation of the πN S-wave amplitudes in the region 8 ≦ s ≦ (M − 1)². The corresponding Argand diagrams show the pseudoresonance behaviour predicted in [1]. The results for the real parts are compared with an independent calculation using fixed-t dispersion relations.     

The effects of silica fillers on the gelation and vitrification of highly filled epoxy‐amine thermosets

Highly filled thermosets are used in applications such as integrated circuit (IC) packaging. However, a detailed understanding of the effects of the fillers on the macroscopic cure properties is limited by the complex cure of such systems. This work systematically quantifies the effects of filler content on the kinetics, gelation and vitrification of a model silica‐filled epoxy/amine system in order to begin to understand the role of the filler in IC packaging cure. At high cure temperatures (100°C and above) there appears to be no effect of fillers on cure kinetics and gelation and vitrification times. However, a decrease in the gelation and vitrification times and increase the reaction rate is seen with increasing filler content at low cure temperatures (60‐90°C). An explanation for these results is given in terms of catalysation of the epoxy amine reaction by hydrogen donor species present on the silica surface and interfacial effects.