Nylon-epoxy interfaces

Certain adhesive systems are more resistant to interfacial degradation by moist environments than are other adhesives. Table 15.16 illustrates that a nitrile-phenolic adhesive does not succumb to failure through the mechanism of preferential displacement at the interface. Failures occurred cohesively within the adhesive even when tested after 24 months of immersion in water. A nylon-epoxy adhesive bond, however, degraded rapidly under the same conditioning owing to its permeability and preferential displacement by moisture. 

The XPS survey spectra from the failure of the bond between epoxy-coated steel and nylon. The upper two spectra are characteristic of the epoxy coating while the lower are typical of nylon. This shows that the two distinct failure regions both exhibit cohesive failure but in the epoxy lacquer (near to the epoxy steel interface) or the nylon (near to the epoxy nylon interface)... 

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