MECHANICAL-PROPERTIES OF HONEYCOMB PREPARED FROM AROMATIC POLYIMIDE FILM

Aromatic polyimides have many advantages such as low thermal expansion coefficient, good electrical insulation, and self-extinguishing prope rties. We tried to use polyimide film for honeycomb structure. Polyimi de honeycomb core and sandwich panel were prepared from polyimide film , i.e., UPILEX R, and adhesive by the expansion method. Mechanical pro perties, i.e., compressive, crushed, shear, and flexural strengths, we re evaluated for this core and panel. Compressive and crushed properti es increased largely with the density of the honeycomb, whereas shear and midspan flexural properties did not vary so much with the density, because these failures occurred in the adhered interface. Strong adhe sion is required for improving the latter properties.