24 июля, 2015 
Malyar As with any other surface coating, it is the final application which governs the choice of the chemical structure of the polymer, because the performance of the film depends more on its chemical structure than on the particular method of applying the film. However, it is worth going through the major requirements of the most common applications of electrodeposited films.
Anticorrosive primers require to be impermeable to water and resistant to alkaline hydrolysis. (This latter because the corrosion reaction produces alkaline conditions). Both these require good cure and the anodic ones are usually cured with phenolic resins. One reason for the superior performance of the cathodic primers is their better resistance to alkali.
A resin intended for applications requiring high throwing power has to be formulated with a high film resistance to provide a good rupture voltage and with a rapid coagulation rate. The latter is largely a matter of making the system as hydrophobic as possible, without making the dispersion unstable. The amount of hydrophobicity which it is possible to build into the system is usually limited by the necessity to provide sites for crosslinking and also the acid or alkaline groups for neutralisation.
Resins for exterior use (such as on window frames) need to be composed of materials known to have good weathering. Thus polyesters should not contain unsaturated acids, and acrylics should have a methyl methacrylate backbone rather than styrene.
Once all the special considerations for the deposition process have been taken into account, it is also necessary to remember that the product is a paint and must have the usual properties required of a paint — film forming, pigment dispersion, correct curing schedule, weathering or other resistance properties, and all the rest. However well the paint deposits, if the final film hasn’t the protective properties needed, it won’t sell in the market place.
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