12 января, 2016 
Pokraskin Lack of cure could be due to a number of factors and this may well depend on the type of adhesive being used.
Cyanoacrylates are very dependent on the presence of small amounts of moisture on the surface and if the relative humidity in the working area is less than 25% RH, the cyanoacrylate will be slow to cure. Surface acidity can also interfere with the curing of cyanoacrylates (see Section 1.2).
Epoxies on the other hand are very independent of the surface condition and, providing the epoxy has been mixed properly (or in the case of single-part epoxies had sufficient heat cure), then the epoxy will cure.
UV acrylics can be inhibited from cure if there is insufficient UV energy to split the photoinitiator and this may occur if the plastics to be bonded are heavily coloured or UV opaque or if there was insufficient intensity from the UV source to initiate cure.
The mix ratio of two-part acrylics is not as critical as the mix ratio of epoxies but the activator part does need to be present for the adhesive to cure. Excessive activator can sometimes result in aggressive curing conditions and thus a weaker final cured polymer. The presence of nitrites on metal surfaces can also inhibit the cure of acrylics.
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