The Journal of Adhesion

Grangeat, Romain; Girard, Marion; de Barros, Silvio; Jacquemin, Frédéric

doi: 10.1080/00218464.2023.2206960pmid: N/A

This overview aims at gathering the various existing works on interphases within epoxy/metal bonded assemblies. Indeed, this particular area plays an important role on the adhesion but also on the behavior in wet environment. Polymeric materials being hydrophilic, water diffusion occurs when they are in a humid environment. The water molecules then have an important impact on the mechanical and physical properties. The effect of water on the interfacial properties of adhesive joints is large discussed in literature. In this article, a complete interphase formation model is be proposed. This two-scenario model explain all the experimental results observed in the literature on the interfaces of a bonded joint. Moreover, hypotheses is made on the water diffusion mechanisms and the diffusive properties of the interface. This is allow explaining the change of the fracture surface observed during the wet aging of a bonded joint. A large number of studies have observed the transition from cohesive to adhesive failure.

Wang, Yaohua; Xu, Fan; Fan, Yiqiang

doi: 10.1080/00218464.2023.2210092pmid: N/A

In this study, a low-cost and rapid bonding method for thermoplastic-based microfluidic devices is introduced. The thermoplastic substrate and cover plate were directly bonded with PES copolyester hot melt adhesive film. Compared with conventional bonding methods for thermoplastic chips, e.g. thermal fusion and chemical-assisted bonding, the proposed bonding process can be finished within minutes without sophisticated instruments or volatile chemical solvents. Several microfluidic devices were also fabricated and tested, the measured bonding strength is comparable to the conventional thermal fusion bonding method. The biocompatibility of the proposed bonding method was also evaluated by culturing bacteria in the PES adhesive covered culture dish. The proposed bonding method for thermoplastic-based microfluidic is especially suitable for the massive fabrication of POCT devices with advantages in processing speed, instrument requirement, cost, and bonding strength.

Anwar, Touhid Bin; Lewis, Taylor N.; Berges, Adam J.; Gately, Thomas J.; Bardeen, Christopher J.

doi: 10.1080/00218464.2023.2211011pmid: N/A

The goal of this paper is to determine whether laser-induced surface melting can generate adhesive debonding. Commercial cyanoacrylate and acrylic adhesives are used to attach an aluminum (Al) cylinder to a transparent polymethyl(methacrylate) (PMMA) plate, and then a variable force is applied to create an axially loaded butt joint. High energy nanosecond laser pulses at 1064 and 532 nm are directed through the transparent PMMA to be absorbed at the Al surface, causing transient localized heating that leads to joint failure. The dependence of this debonding on both laser fluence (energy per area) and applied force are investigated. Single shot debonding occurs at fluences on the order of 0.47 J/cm2 for 1064 nm and 0.29 J/cm2 for 532 nm pulses with an applied pressure of 0.22 MPa. Characterization of the Al surface before and after laser impact confirms that the debonding arises from surface melting and causes only slight changes to the Al surface. A simple model of the debonding process is developed to explain the dependence of the debonding on the applied load. Single laser pulses can generate instantaneous, relatively clean separation of bonded joints, suggesting that laser debonding may be a promising strategy to initiate deadhesion.

Feng, Yingmin; Han, Xu; Ji, Yumei; Li, Shaolong; Dong, Kongyu; Liang, Shuo; Ma, Yao; Yang, Yike; Liu, Feng

doi: 10.1080/00218464.2023.2211930pmid: N/A

The development of adhesives with excellent reversibility is necessary for the removal, recycling and reusing of precision components under specific conditions in electronics manufacturing. The integration of photosensitive cycloaddition reactions into common adhesive systems is a viable alternative for reversible modification. In this contribution, a novel reversible acrylate adhesive was successfully prepared by doping thiol-functionalized anthracene derivatives in situ, and its characteristic structure, photophysical properties and mechanical performance were systematically evaluated. As expected, the reversible dimers structure of anthracene provides remarkable bonding and debonding properties for adhesives. Sample #3 achieved an excellent shear strength of 1.67 ± 0.07 MPa and 91% debonding rate, with 283.03% and 89.58% improvement over the control sample #0 without anthracene modification, respectively. Furthermore, the shear strength and debonding rate for secondary bonding were up to 2.37 ± 0.07 MPa and 82%. We believe that our paradigm can provide a feasible approach for reversible adhesive design.