Frost - Flowering - Chlorosis. Whatever you call it, we all recognize it as unattractive white material, which can sometimes occur when using instant adhesives.
The residue is a by-product of the glue curing process. Once the monomer is in vapor form, it will react with moisture in the air, curing and settling on the surface around the bond area.
The short answer to the question of how to prevent flowering or frosting is a “quick cure” or choose one of the low carbon cyanoacrylate formulations.
Treatment with cyanoacrylate causes traces of moisture on the surfaces of the substrate. Cure rates decrease in low humidity conditions. The gluing speed is slower when gluing acidic substrates, such as wood or paper, and increases the time required to achieve durability during processing and complete curing.
The work area should be well ventilated for best results.
Optimal results for curing cyanoacrylates begin with the use of a minimum amount of glue. This helps to avoid “squeezing” the glue and minimizes or eliminates flowering. The end result is an aesthetically pleasing appearance and a strong bond.
Use an accelerator to increase the cure speed of the glue. Depending on the application, the accelerator may be deposited on the substrate before the glue. In other situations, the accelerator is applied to the mating surfaces, where it connects with the joint to speed up the cure time.
Choose a product with a low odor / low bloom. These formulas have a lower vapor pressure and higher molecular weight to minimize flowering and reduce the characteristic odor associated with instant adhesives. Low odor / low flowering cyanoacrylates have lower resistance to working temperatures and may not be suitable for all applications.
The emergence of flowering is primarily an aesthetic consideration. But this is a particular problem when industrial devices are packaged immediately after assembly. This can lead to the capture of volatile substances before they can polymerize and continue flowering.
Thus, choosing the right cyanoacrylate formula (with or without an accelerator) for component substrates along with recommended environmental conditions to stimulate rapid curing are the steps necessary to reduce or prevent flowering or chlorosis when binding to cyanoacrylate adhesives,
