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It’s always been a major challenge to protect buildings and public infrastructure from nature’s elements. Take bridges, for example. According to the 2021 Infrastructure Report Card, 42% are at least 50 years old and 7.5% of the U.S.’s 617,000 bridges are “structurally deficient,” meaning they are in poor condition. As the government makes new investments in repairing bridges across America, fluoropolymer coatings and paints offer a sustainable and high-performance solution in bridge maintenance.
AGC formulators continually strive to develop resins for coatings that provide superior protection for public infrastructure. We’ve been doing so for decades with our LUMIFLON® FEVE of fluoropolymer coatings and resins. The following is a brief timeline of the evolution and use of fluoropolymer coatings.
1940s — Polyurethane Resins
In the 1940s, polyurethane resins were first produced and applied to protective topcoats. Due to their high gloss, these resins quickly became the most widely used ingredient in topcoat formulations.
Polyurethane resins offer fair protection against weathering and degradation. Bridges coated with polyurethane topcoats have a life-cycle of 20 to 30 years. However, during this life-cycle, they usually lose significant color and gloss, and require touch-ups or re-coats due to spot corrosion.
1960s — Fluoropolymer Resins
The coatings industry began using fluoropolymer resins in the 1960s. These topcoats were more durable, and had improved performance properties including long-term weather resistance. In addition, these resins were resistant to:
- Chemicals
- Heat
- Water
- Petroleum products
These performance benefits have made fluoropolymer coatings ideal for many applications across many industries, including paper, plastics, textiles, oil and gas. However, they had limitations.
Traditional fluoropolymer resin deficiencies:
- Poor solubility in conventional solvents
- Require heat to cure
- Low surface energy that limits their adhesion to metals and other substrates.
1980s — Fluoroethylene Vinyl Ether Resins
Fluoroethylene vinyl ether (FEVE) resins became popular in the 1980s. Compared to traditional fluoropolymers, FEVEs offer the same outstanding weatherability and durability, but are soluble in solvents and available as water-based dispersions and emulsions.
This transparent fluoropolymer resin is used in both clear and colored paints. In the beginning, FEVE fluoropolymer coatings were applied mainly for aesthetic purposes because they retained a high-gloss finish with greater superiority over urethane or polyester-based paints. But they soon proved even more valuable for their ability to prevent corrosion. FEVE resins can be cross-linked much like polyurethane resins, so they are ideal for protective topcoats in corrosive environments.
FEVE fluoropolymer coatings also are extremely weather-resistant against UV rays, wind, precipitation, dirt, and chemicals. Because they last longer, they reduce maintenance and recoating costs while decreasing the environmental impact of repainting and recoating.
Beneficial properties of FEVE fluoropolymer coatings include:
- The high-energy carbon-fluorine bond in the backbone of the FEVE polymer provides excellent resistance to UV exposure and harsh chemicals.
- Hydroxyl functionality allows for cross-linking of the FEVE resin. Polyurethane-type topcoats also can utilize it.
- FEVE resins don’t require heat curing, so they are easily applied in the factory or field.
- Do not require a solvent and have high recyclability and reclaimability.
FEVE-based LUMIFLON® Curable at Room Temperature
LUMIFLON® is the first solvent-soluble fluoropolymer resin for coatings that is curable at room temperatures. With a FEVE structure, it possesses high durability and weatherability, resisting degradation from UV light, wind, rain, and corrosion to protect steel, aluminum, and other metals. Transparent and with high pigment dispersiveness, this FEVE fluoropolymer can be formulated into coatings with a range of glosses and colors.
Developed by AGC in 1982, LUMIFLON resins have been used as heavy-duty coatings for bridges, towers, chemical plants, buildings, and vehicles. They also improve the performance of all types of functional coatings. LUMIFLON fluoropolymer coatings are available in solvent-based, waterborne, and flake grades to meet specific application methods and environmental regulations.
FEVE-based Coatings Lower Life Cycle Costs
The initial purchase price for FEVE-based topcoats is higher than standard polyurethane topcoats, but they have a lower life cycle cost. That’s because FEVE resin formulations protect against corrosion and maintain color and gloss for 30 years or longer without re-coating. The result is lower maintenance costs and zero waste generated.
Corrosion and UV degradation are the primary enemies of public infrastructures and other outdoor buildings. While polyurethane technology is the workhorse chemistry for protective topcoats, it offers limited protection against corrosion and UV degradation. FEVE resin technology is the next generation in high-performance fluoropolymer coating because it exhibits superior resistance to ultraviolet exposure, wind, and extreme temperatures.
Find more about LUMIFLON FEVE-based fluoropolymer coatings here or contact an AGC specialist at 1-800-424-7833.