Experimental investigation on the effect of nanostructuration on the adherence properties of epoxy adhesives by a probe tack test

Abstract

a b s t r a c tIn this work, we aimed to characterize the energy of adherence of nanoscale structured epoxy adhesives Diglycidyl ether of bisphenol-A/Methylene-diethylaniline (DGEBA/MDEA) induced by phase separation triblock copolymers Poly (Methacrylate de Methyl)-b-Poly (Butyl Acrylate)-b-Poly (Methyl Methacrylate) (PMMA-b-PBA-b-PMMA) at gel state by a probe tack test, which is an original use of this kind of test for thermoset adhesives. For a set of mechanical parameters (probe's roughness, contact time, contact pressure and debonding velocity), we measured the energy of adherence for both neat and filled adhesives. The probe tack test was performed at different steps of gelation. We compared the behavior of the adhesives and evaluated the dissipation contribution to the energy of adherence of the adhesives during the test. We finally discussed the nanoparticles' influence on the competition between cavitation and fibrillation. We report that the addition of nanoparticles leads to an overall improvement of the energy of adherence, with a significant increase of the dissipation contribution to the energy measured.

Tack Properties of Nanostructured Epoxy–Amine Resins on Plasma-Treated Glass Substrates

“…While this description is sufficient for thermoplastic polymers, as extensively demonstrated for pressure-sensitive adhesives (PSA), it may not be sufficient to describe thermosetting resins. Indeed, as reported in our previous study, the tack of thermosetting polymers is accompanied by a viscous flow. To highlight its existence, we manually placed bubbles as tracers slightly outside the contact zone.…”

“…The method to determine the range for which the tack energy was measurable and its actual measure on degreased substrates was reported earlier . For all resins and both treatments, the tack energy passed through a maximum.…”

“…7 For all resins and both treatments, the tack energy passed through a maximum. 7 The isothermal cross-linking time at which the maximum of tack was recorded for both treatments is shown in Table 2. As explained in the section about the samples' preparation, the plasma treatment did not influence the isothermal cross-linking time that gave the maximum tack but changed the actual values of the tack energy, as will be discussed below.…”

“…The method to determine the range for which the tack energy was measurable and its actual measure on degreased substrates was reported earlier. 7 For all resins and both treatments, the tack energy passed through a maximum. 7 The isothermal cross-linking time at which the maximum of tack was recorded for both treatments is shown in Table 2.…”

“…This peculiar property is needed for reliably positioning the prepreg during manufacturing, as well as to prevent sliding during lay-up of a laminate. , In all cases (bonding glass, prepreg manufacture, etc...), the nanostructuration of the epoxy resins and the influence of the substrates’ surface treatment are key parameters directly influencing the stickiness . In a previous report, we used a probe tack test on a glass coated with epoxy–amine resins nanostructured by thermoplastic triblock copolymers. By using this test, we were able to discriminate the influence of the copolymers on the interfacial strength, on the one hand, and cohesion, on the other hand.…”