Mechanical characterization of natural nano-structured zeolite/polyurethane filled 3D woven glass fiber composite sandwich panels

3D woven glass fibers sandwich panels have become the focus of interest due to their inherent light weight and, thus, their remarkable stiffness. However, a question is that whether their hollow galleries could be filled with still light materials which even at the same time contribute to their mechanical performance. This work examines the effect of porous polymer nanocomposites filling galleries of such panels on mechanical response of newly formed hybrid composites. To achieve this, the nanocomposites of natural nano-structured zeolite/polyurethane foams were fabricated and injected within 3D woven glass fibers sandwich panels. Mechanical characterization techniques including the flatwise compression, edgewise compression, three-point bending and drop weight impact were carried out to understand the effect of addition of the reinforced foam on the mechanical response of the specimens. It is shown that the polyurethane foam reinforced with natural nano-structured zeolite particles significantly improves the flexural strength, ultimate load and energy absorption of the filled composite sandwich panels. It is also demonstrated that the damage and local wrinkling failure compared with other typical sandwich panels do not occur due to the presence of the glass fiber yarns vertically located between panel sheets. These type of composites provide high specific strength results from high-performance and low-density structure.