A Comparison of Cyanoacrylates with Other Adhesives

The properties of cyanoacrylate adhesives have been discussed in detail in the previous sections of this chapter. The evaluation of these adhesives is complemented in this section by comparisons with other structural adhesives. A specific comparison has been made of cyanoacrylate adhesives with a two-part epoxy, EC 2216 B/A, and a two-part polyurethane, EC 3549 B/A, all sold by 3M. The substrates on which the adhesives were tested were aluminum, polystyrene, and chloroprene. The results for room temperature water immersion, 90°F/90% relative humidity, and 150°F oven aging are shown in Tables XVI and XVII. 

The data in Tables XVI and XVII show that cyanoacrylates lack durability on metal surfaces and that the durability on chloroprene is moderate. On the other hand, the cyanoacrylate is more durable than the epoxy and as durable as the polyurethane on polystyrene under moist aging conditions. 

Adhesive Conditions Polystyrene Strength (MPa) after Chloroprene Strength (MPa) after  

25 mm x 200 mm x 3.2 mm coupons, MEK-wiped,Scotch-Brite -abraded,MEK-wiped, 3.25 cm bond area. CA-4, medium-viscosity general purpose cyanoacrylate sold by 3M Company. 

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