Coating composition including an unsaturated polymer
View Patent ↗A coating composition is described. The coating composition preferably includes an unsaturated polymer such as, for example, an unsaturated polyester polymer; an ether component including one or more ether groups; and an optional liquid carrier. In preferred embodiments, the unsaturated polymer preferably has an iodine value of at least 10. The coating composition is useful in coating a variety of substrates, including planar metal substrates.
1. A method comprising:
providing a thermally crosslinkable coating composition comprising
at least 5% of an unsaturated polymer having an iodine value of at least 10, based on the total weight of nonvolatile material in the coating composition; and
an ether component including one or more ether groups, and a liquid carrier;
applying the coating composition to at least a portion of a planar metal substrate; and
heating the coated metal substrate for about 5 to 900 seconds to a peak metal temperature of at least 425° F. to form a crosslinked coating.
2. The method of claim 1 , wherein the coating composition includes an efficacious amount of the ether component.
3. The method of claim 1 , wherein the unsaturated polymer comprises a polyamide, a polycarbonate, a polyester, a polyether, a polyurea, a copolymer thereof, or a mixture thereof.
4. The method of claim 1 , wherein the coating composition includes at least 50 weight percent of the unsaturated polymer, based on the total weight of nonvolatile material in the coating composition.
5. The method of claim 1 , wherein the unsaturated polymer has an iodine value of at least 20.
6. The method of claim 1 , wherein the unsaturated polymer comprises a polyester polymer.
7. The method of claim 1 , wherein the ether component comprises a second polymer that includes the one or more ether groups.
8. The method of claim 1 , wherein the ether component comprises tripropylene glycol, a structural unit derived from tripropylene glycol, or a combination thereof.
9. The method of claim 1 , wherein the unsaturated polymer includes one or more aliphatic carbon-carbon double bonds that comprise a vinylic double bond, a conjugated double bond, a double bond present in a strained ring group, a double bond present in an unsaturated polycyclic group, or a combination thereof.
10. The method of claim 1 , wherein the coating composition is applied to a food-contact surface of the planar metal substrate.
11. The method of claim 1 , wherein the planar metal substrate comprises metal coil.
12. The method of claim 1 , wherein the coating composition is a water-based coating composition that may optionally include organic solvent.
13. The method of claim 1 , wherein the unsaturated polymer includes one or more segments derived from an unsaturated polybutadiene compound.
14. The method of claim 1 , wherein the unsaturated polymer is formed from ingredients including, based on total non-volatiles, at least 5% by weight of the unsaturated polybutadiene compound.
15. A coated article formed using the method of claim 1 .
16. The coated article of claim 15 , wherein the coated article comprises a food or beverage container or a portion thereof.
17. The method of claim 1 , wherein the unsaturated polymer includes the ether component.
18. The method of claim 17 , wherein the unsaturated polymer includes at least 1% by weight of ether oxygen.
19. The method of claim 1 , wherein the ether component comprises a low-molecular-weight organic compound that includes the one or more ether groups.
20. The method of claim 19 , wherein the low-molecular-weight organic compound is a volatile organic compound that includes two or more ether groups.