Improvement of the structural, thermal, and mechanical properties of polyurethane adhesives with nanoparticles and their application to Al/Al honeycomb sandwich panels

Abstract Understanding the relationship between core/face adhesive interface and performance of MWCNT added nanoadhesives are essential for better designing and fabrication of aluminum honeycomb sandwich panels. In this study, we used multi-walled carbon nanotubes (MWCNTs) to prepare enhanced interfacial adhesion between honeycomb core and aluminum facesheet. MWCNTs are first introduced to isocyanate, and then MWCNTs/isocyanate blend poured into polyol to produce MWCNTs reinforced polyurethane (PU) nanoadhesives. The relationship between core/face adhesive interface and performance of MWCNT added nanoadhesives are investigated in detail in terms of thermogravimetric analyses (TGA), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, edge-wise compression tests, flat-wise tensile tests and three-point bending tests The experimental results showed that the MWCNT addition to PU adhesive led to enhanced thermal stability, flat-wise tensile strength and edge-wise compression strength for sandwich structures. This study gives a significant reference indicator on the fabrication of an improved core/face interface for obtaining sandwich panels with desired mechanical properties.