Thermoplastic Adhesive for Automotive Applications

Proceedings of the Institution of Mechanical Engineers, Part C:

Martorana

Lambertini

et al. 2017

A hot melt adhesive -mainly used for bonding plastic component in automotive field -was modified with different ironbased particles to give it a reversible behaviour. Mechanical and physical properties of these reversible adhesives were experimentally assessed in the work. The modified adhesives, coupled with electromagnetic induction, are able to guarantee separation of the joints without any damage to the substrates for recycling, reuse or repairing of components. Single lap joint specimens were prepared using epoxy/glass fibres substrates and tests were carried out on neat and modified adhesive with 5% weight of iron and iron oxide. Three different Fe particles size were tested: 450 mm, 60 mm and 1-6 mm. The particles size of iron oxide was 50 nm. Separation was studied using single lap joint specimens under electro-magnetic induction. Experimental results showed that the maximum peak load decreases when the average particles sizes increase. The peak loads of the smallest particles were equal to the ones of the pristine adhesive. The elongation of the adhesives increases when the adhesive is modified with both iron and iron oxide particles. Finally, experimental tests on single lap joints coupled with electro-magnetic induction showed that separation of the substrates is possible using iron oxide particles. Electro-magnetic tests conducted on particles alone, helped to understand that bigger particles are able to overcome the melting temperature of the adhesive but hot-melt adhesives modified with these particles are not able to reach the melting. These tests showed that the number of particles into the adhesive matrix is very important for this kind of tests.

Section: Methodsmentioning

confidence: 99%

“…This configuration was used also in literature. 7,10,17,20 At least, three joints were tested for each concentration of nanoparticles.…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Iron-based reversible adhesives: Effect of particles size on mechanical properties

Proceedings of the Institution of Mechanical Engineers, Part C:

Martorana

Lambertini

et al. 2017

“…The nano-modified adhesive is prepared by using a hot plate for melting the neat adhesive and by adding 10% in weight of iron oxide particles with size smaller than 50 nm (Fe3O4 by Sigma-Aldrich, Saint Louis, United States). Following a procedure commonly adopted in the literature for HMA [6,9,11,13], the pellets were melted together at 190°C, using the hot plate. At 190°C, the viscosity of the adhesive was low enough to easily mix the particles into the adhesive by mean of a glass road.…”

Section: Methodsmentioning

confidence: 99%

“…Thermoset adhesives are generally employed for structural joints but, in the last years, there has been a significant increment in the use of thermoplastic adhesives, too. In some specific applications, thermoplastic adhesives are even preferable to traditional thermoset adhesives for their ease of application and for their flexibility in joining different kinds of plastic materials, even hard to bond, such as polypropylene [6]. The reason of this increase is due the adoption of many polypropylene (PP) based materials that have replaced plastics and many metals, especially in automotive sector [7].…”

Section: Introductionmentioning

confidence: 99%

Impact response of adhesive reversible joints made of thermoplastic nanomodified adhesive

The Journal of Adhesion

Tridello

Brunella

et al. 2018

The impact response of a reversible adhesive joint is experimentally assessed in the work. Joint reversibility is improved with a system that uses nano-modification of the thermoplastic adhesive used for bonding plastic components. This system, coupled with electromagnetic induction, is able to guarantee separation of the joints without any damage to the substrates. Drop dart tests at different impact velocities are carried out on neat and nano-modified bonded joints in order to compare the impact behaviour before and after the introduction of nanoparticles. Experimental results show that the impact response, assessed in terms of peak load, absorbed energy and flexural stiffness, can be affected by the introduction of nanoparticles. This work shows that adhesive nano-modified joints represent an effective and applicable solution for the reversible assembling of semi-structural components subjected to low-velocity impact loads.

Mechanical properties of a reversible adhesive used to separate adhesive joints

Mat Design & Process Comms

2020

Self Cite

In this work, the mechanical characterization of adhesive joints made with a thermoplastic adhesive, modified and not modified, has been presented together with the separation tests that are possible by the use of metal nanoparticles embedded within the adhesive. A polyolefin adhesive has been modified with two weight concentrations (5% and 10%) of iron oxide nanoparticles. These particles increase their temperature under electromagnetic field; in this way, they are able to melt the adhesive and, therefore, separate the adhesive joints. The mechanical properties of single lap joints (SLJs) prepared with the neat and modified adhesives have been performed by using different overlap lengths and thicknesses. SLJs prepared with the nanomodified adhesive present higher loads compared with the neat one. Separation tests have been carried out on SLJ specimens to measure the times needed to disassemble the adhesive joints. Scanning electron microscope analysis has been carried out to study the distribution of the particles.