Cyanoacrylates vapour

When excess adhesive has been applied, the surface to volume-of-adhesive ratio is too low and the moisture on the surface will be insufficient to neutralise the stabiliser in the adhesive. The cyanoacrylate vapour will escape and fuming will occur. Reduce the quantity of the adhesive by using fine bore application nozzles and/or dispensing equipment. 

Cyanoacrylates have been used in industry for many years with an excellent safety record. Vapour problems will not normally be of concern in a well ventilated working area, and can be eliminated with the use of low odour/low bloom cyanoacrylates. 

Blooming occurs when cyanoacrylate molecules escape from the main body of the adhesive and react with water vapour in the surrounding air. The molecules of cyanoacrylate cure and then fall to the adjacent surface as a white powder. Even with rubber toughened cyanoacrylates, (which are often black in colour) it is the monomer which escapes and the deposit will still be white (see Figure 10.18). 

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