Two-part epoxy compositions for adherent coatings of storage articles
A two-part epoxy coating composition for producing an adherent coating for articles such as large liquid storage tanks. The two-part epoxy coating composition includes a first liquid comprising a polyepoxide having a described formula and having an estrogenic agonist activity less than that of bisphenol S, and a second liquid comprising a curing agent configured to react with the polyepoxide under ambient conditions.
1. A two-part epoxy composition comprising:
a first liquid comprising a polyepoxide of Formula (I):
wherein the polyepoxide of Formula (I) comprises tetramethyl bisphenol F diglycidyl ether;
wherein the polyepoxide of Formula (I) has an estrogenic agonist activity less than that of bisphenol S;
wherein the polyepoxide of Formula (I) has a viscosity of about 5,000 poise to about 15,000 poise at 25° C.; and
a second liquid comprising a curing agent configured to react with the polyepoxide under 25° C.;
wherein the curing agent comprises triethylenetetramine (TETA).
2. The two-part epoxy composition of claim 1 , wherein the ether oxygen atom of each phenylene group depicted in Formula (I) is located at a para position relative to: (i) R 2 or (ii) a ring-ring covalent linkage if n is 0 and R 2 is absent.
3. The two-part epoxy composition of claim 1 , wherein n is 1.
4. The two-part epoxy composition of claim 3 , wherein R 2 is a methylene group.
5. The two-part epoxy composition of claim 3 , wherein R 3 is a methylene group.
6. The two-part epoxy composition of claim 1 , wherein the two-part epoxy composition is substantially free of mobile bisphenol A and a diglycidyl ether of bisphenol A.
7. The two-part epoxy composition of claim 1 , wherein the two-part epoxy composition is substantially free of mobile polyhydric phenols, and epoxides thereof, having an estrogenic agonist activity equal to or greater than bisphenol S.
8. The two-part epoxy composition of claim 1 , wherein the polyepoxide of Formula (I) has an atomic weight of less than 600 Daltons.
9. The two-part epoxy composition of claim 1 , wherein the polyepoxide of Formula (I) constitutes at least 50% by weight of the two-part epoxy composition.