"Adhesive bonding is a more efficient joining method for composites than traditional mechanical fasteners and provides advantages in weight reduction, simplicity, and cost. In addition, the utilization of mechanical fasteners introduces stress concentrations and damage to the fiber-matrix interface. Adhesive bonding with thermoset polymers distributes mechanical loads but also makes disassembly for repair and recycling difficult. The ability to utilize thermoplastic polymers as adhesives offers an approach to address these limitations and can even produce a reversible adhesive joining technology through combining conductive nanoparticles with a thermoplastic polymer. The incorporation of the conductive nanoparticles allows for selective heating of the adhesive via exposure to electromagnetic (EM) radiation and simultaneously can augment the mechanical properties of the adhesive and the adhesive joint. This approach provides a versatile mechanism for efficiently creating and reversing structural adhesive joints across a wide range of materials. In this work, a high-impact polystyrene (HIPS) co-polymer containing butadiene as a toughness modifier is compounded with graphene nano-platelets (GnP) for investigation as a thermoplastic adhesive. The properties of the bulk composite adhesive are tailored by altering the morphology, dispersion, and concentration of GnP. The thermal response of the material to EM radiation in the microwave frequency spectrum was investigated and optimized. Surface treatments of the adhesive films were explored to enhance the viability of this nanoparticle thermoplastic polymer to function as a reversible adhesive. As a result, it has been shown that lap-shear strengths of multi-material joints produced from aforementioned thermoplastic adhesives were comparable to similar thermoset bonded joints."--Page ii.
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