Eliminating PFAS Compounds in Powder Coatings
Posted on Thursday, September 21, 2023
By Shelley Verdun
Powder coatings have come a long way since their infancy around 80 years ago. Today, advanced resins, crosslinking agents, and unique additives are helping to create novel new finishes never before possible, taking corrosion protection to the next level and fostering the development of innovations like antimicrobial-protected and electro dissipative powders. But the evolution of powder coatings goes far beyond aesthetics and performance.
Increasingly efficient and cost-effective application methods, coupled with rising interest in environmentally sound manufacturing practices, have contributed to powder climbing to one of the fastest growing coating technologies in the world.
One of the most well-known and appealing benefits of powder coatings is that they are generally formulated without solvents that release harmful volatile organic compounds (VOCs) into the air, the subject of intense regulatory control around the world. But efforts to improve the ecological benefits of powder coatings beyond low VOC content are ongoing and ambitious.
Sizeable investments in research and development (R&D) are driving the development of protective powder coatings that reduce their overall impact on the environment and take sustainability advantages to the next level. These innovations range from high transfer efficient formulations that require less powder for complete coverage, to low-cure formulations that require less energy to cure. Evolutionary advancements in the design of spray booth equipment are also expanding the opportunities to reclaim and reuse powder overspray.
More recently, however, a newer sustainability focus among makers of industrial coatings and their manufacturing customers is the development and adoption of powders that are formulated without PFAS compounds. Known for their resiliency, non-stick, durability and stain- and water-resistance, PFAS chemicals, short for per- and polyfluoroalkyl substances, are a class of over 12,000 different chemicals that have been used for decades in a wide range of consumer and industrial products like furniture, cosmetics, food packaging, building materials, and skillets.
While the unique properties of highly stable and resilient PFAS chemicals are hard to replicate, they do come with some notable downsides, including the inability to break down in the environment over time.
PFAS molecules are comprised of a chain of linked fluorine and carbon atoms. How concerning a specific PFAS substance is depends on its molecular weight and chemical structure, with long-chain compounds (those with more fluorinated carbons) coming under intense scrutiny and regulatory oversight. Research is ongoing to explore the most effective methods to break or degrade these bonds.
In the meantime, the U.S. Environmental Protection Agency is implementing a robust roadmap to regulate PFAS in drinking water, air, waste, and products. Several states, including California, Minnesota, Maine, and New Jersey, are introducing their own regulations to restrict the use of PFAS compounds. The state of California, for example, banned the use of PFAS in products for children, a rule that will be implemented in all schools later this year. Similar efforts are underway in Europe.
But government agencies around the world are not acting alone. Ahead of new regulations, manufacturers and businesses are proactively limiting or eliminating the use of these chemicals of concern. Outdoor goods retailer REI, for instance, announced plans earlier this year to stop selling cookware and clothing products that contain PFAS substances starting in late 2024, and manufacturers are developing newer and more sustainable protective coatings formulations.
Continuous Innovation in the Office Furniture Market
As a powder coating supplier for metal office furniture, storage, and locker system manufacturers, PPG works closely with top companies in these industries to develop the colors, textures, and formulations that meet the needs of their respective customers. R&D initiatives aim to engineer products that are formulated with fewer chemicals of concern yet provide the same, or better, coverage, quality, and performance.
When it comes to PFAS compounds, the metal office furniture industry has been leading the charge for an alternative solution that does not contain polytetrafluoroethylene (PTFE), a high-molecular-weight polymer that is one of the most widely used PFAS chemicals.
However, finding an alternative solution that was better for the environment wasn’t enough; the coating also needed to deliver on performance in terms of long-term stain resistance, color, and gloss retention, along with the ability to withstand abrasions and marring from heavy use in high traffic settings. Plus, it had to be available in standard or custom color options and metallics.
While PTFE alternatives have been used in the past to provide textured finishes in powder coatings, none of the standard options truly provided the same high quality as those formulated with PTFE substances. The effort to
develop a coating with the same high-performance properties and consistency as PTFE-containing powders has been in development for more than a year.
In 2021, PPG launched ERGOLUXE™ coating, a polyester- epoxy hybrid powder for seating solutions, desks, cabinets, and more, followed by the next generation of the powder that contained up to 14% recycled polyethylene terephthalate (rPET).
This spring, PPG announced new ERGOLUXE formulations that are made without intentionally added PTFE chemicals for both smooth and textured finishes, a breakthrough in the industry. This new generation of protective power coatings is virtually indistinguishable in performance from the original formulation in terms of hardness, flexibility, durability, as well as stain-, scratch-, and fade-resistance.
“Finding the right set of additives to create a textured finish proved to be the most challenging since those required a different formula to get the same performance as a PTFE-based coating,” said Ben MacFadden, powder product development manager for PPG Industrial Coatings. “Now all customers in the furniture space will have a durable and safer powder alternative regardless of aesthetic needs.”
Today, these revolutionary powder formulations that are available for the metal office furniture and storage industries have broad implications for other industries. “We expect that the technology will soon be available for appliances and insulated drinkware,” added MacFadden.
PTFE alternative solutions are currently available for interior applications, but research is underway to create formulations that offer the durability of standard FEVE fluoropolymers for use on exterior architectural applications. While the industry is not there yet, it is moving in that direction with products that contain less PFAS compounds than previous generations.
It’s clear that we are living in the infancy of the PFAS-free movement and companies are investing in R&D to formulate more sustainable powder innovations to help meet the needs of our customers and the environmental challenges of our times.
Sustainability is the Future
Exploring ways to make great products with fewer chemicals of concern is a big focus of manufacturers and their customers, but it’s not the only one. The era of sustainable manufacturing is here with companies of every size embracing initiatives that improve operational efficiencies; lower carbon footprints; reduce water, energy, and waste; and utilize more renewable energy sources.
It’s becoming abundantly clear that these moves are not only better for the environment but make sound business practices as consumer preferences are shifting towards ethically and more sustainably made goods. Powder coatings, particularly newer generations, are factoring into the finishing decisions of these products more than ever.
Coatings companies will continue the work to innovate newer classes of powders that are not only formulated without PFAS compounds like PTFE but are viable for a broader range of applications, substrates, and industries.
Shelley Verdun is business manager, powder coatings, America’s region for PPG.