10 августа, 2015 
Malyar Bisphenol “A” epoxy resins, with an epoxy equivalent weight of 500 or higher, are used in all classes of thermosetting acrylics.
When used in conjunction with acrylamide based acrylics at levels up to 10% (based on total solid resin) they enhance adhesion to metals, flexibility, toughness and chemical resistance.
However, a maximum level of between 5 to 7.5% epoxy resin should be used where exterior durability is a requirement. This is due to the fact that higher levels of epoxy give rise to an early onset of chalking.
The same general comments apply when epoxy resin additions are made to hydroxy acrylic/amino resin combinations. In addition, the presence of epoxy resins in these systems means that the curing temperature must be raised, from 120°C to between 140 and 150°C, in order fully to exploit the improvement in performance expected from such modifications.
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