Isophthalic Polyester Coating
Definition - What does Isophthalic Polyester Coating mean?
This is a high-quality surface protection gel or lining that contains polyester resins, which that include isophthalic acid (purified isophthalic acid or PIA) as an intermediate or saturated monomer. The isophthalic acid enhances chemical resistance, though it increases the product cost of isophthalic polyester. It is applied in chemical service applications on automobiles, marine vessels, tanks and pipelines to provide corrosion resistance.
Corrosionpedia explains Isophthalic Polyester Coating
It takes a ratio of 1 mole of isophthalic acid to 1 mole of fumaric acid with propylene glycol or Maleic anhydride to make a standard grade of isophthalic polyester coating through crosslinking and polymerization processes. The use of isophthalic acid makes it obtain a high glass transition temperature. It provides adhesion to steel or concrete substrates. The liquid resin can be solidified by the use of catalysts like peroxide.
This coating has overall durability, and resistance to water, solvent or chemical weathering. It cures at low temperatures; hence it can be used in ambient conditions. It also has a fast curing time without post curing. The coating is not resistant to higher concentrations of oxidizing acids. The coating contains marr, stain and corrosion resistance with an outstanding hardness. However, when used, it produces a flat, eggshell, matt or semi-gloss finish. Its durability is attributed by the hydrolytic stability of isophthalic esters.