Thermomechanical characterization of reinforced and dismountable thermoplastic adhesive joints activated by microwave and induction processes

In this work, a thermoplastic adhesive used by automotive industries for bonding plastic components has been modified with iron oxide nanoparticles to ease the dismounting process. Two different processes have been considered for the joint dismounting, namely the already studied electromagnetic induction and an innovative microwave heating process. Besides the mentioned heating activation process, a full experimental plan has been designed that includes two different weight percentages (5% and 10%) of the nanoparticles and two alternative mixing methods: hand-mixing and extrusion methods. The mechanical performances and the separation tests have been assessed by using single lap joints. The adhesive joints prepared with the nanomodified adhesives and with the hand-mixing method presents a slightly larger value of the maximum strength due to the presence of small agglomerates that have been observed with scanning electron microscope analysis. On the other hand, the extrusion method gave a very uniform distribution of the particles within the adhesive matrix. Microwave and induction heating tests conducted on both the single lap joint and the adhesive itself showed that the joint separation and the melting of the adhesive are possible by using both adhesives prepared with the two mixing methods.