Epoxy coatings are commonly used in oil fields, offshor […]
Epoxy coatings are commonly used in oil fields, offshore and petrochemical facilities and are favored for their impact resistance and abrasion resistance. Epoxy coatings are organic polymers produced by chemical reactions between epoxy resins and co-reactants / curing agents / curing agents. Epoxy resins are also thermoset, which means that once cured, they do not melt and reform like vinyl or plastic cans. Excessive heat will destroy the chemical bonds in the thermoset material, causing it to degrade, discolor, lose ductility or become brittle. Epoxy resin is also susceptible to solar radiation and powders in the sun.
Epoxy phenolic coatings are classified as environmental curing, where phenolic and epoxy resins undergo a chemical reaction at room temperature, or are thermally cured, where the coating is exposed to a temperature of 350-400 ° F to accelerate curing or activate catalysts or additives in cured coating Agent. Epoxy phenolic resin has chemical resistance, solvent resistance and high temperature resistance. It is usually used for immersion service, tank lining and high temperature oil and salt water immersion service. Other suitable applications require strict chemical resistance but do not require a high degree of flexibility.
The advantages of epoxy phenolic resins include excellent adhesion properties, heat resistance up to 400 ° F, and solvent, chemical and abrasion resistance. Limitations include reduced weatherability and flexibility, relatively slow air curing times, and often the need for thermal curing at higher temperatures.
Epoxy novolac coatings have higher heat resistance and more cross-linking properties than other epoxy resins because of their aromaticity in the molecular structure. The heat resistance of novolac epoxy resins is typically as high as 350 -360 ° F. In general, novolak epoxy resins are more resistant to oxidizing and non-oxidizing acids as well as aliphatic and aromatic solvents compared to other epoxy resins. These properties make novolak epoxy resins the choice of choice for applications such as tank linings in contact with high temperature acid crudes.