The Truth About PTFE and the Need for Sustainable Coatings

Fluoropolymers are used nearly everywhere, in almost every major manufacturing sector. Those of us who manufacture and use the coatings, and our manufacturing customers, understand the unique benefits they bring to everyday life, but many others do not. Like other industrial sectors before them, fluoropolymers have come under fire for allegedly causing harm to people and the environment and the search is on for more sustainable coatings that perform at least as well or better.

Before perfluorooctane sulfonic acid (PFOA) was banned in 2015, the story goes that a lady was heard to say she would never use coated cookware. When asked why not, she replied, “because I know that big companies lie.”

Maintaining a good reputation is not easy. What is easy is losing that reputation. This is especially true today with how events are portrayed in the media. Claims that have little or no basis in fact, if loud enough, can set regulating agencies into motion. A few well-placed social media posts can be enough to incite protests, but is anyone pausing to ask questions and challenge the claims? Does anyone realize what the world would be like without fluoropolymers that make so much of what we buy and use, including life-saving medical devices, possible?

Spreading the Truth

Instead of allowing misperceptions to fester and further damage the industry’s reputation, what is needed is advocacy and education of consumers, product design engineers, and the agencies seeking to eliminate fluoropolymer usage.

For more than a decade, regulatory agencies including the U.S. Environmental Protection Agency (EPA) and the EU Medical Device Regulation (MDR) have scrutinized fluoropolymers used to manufacture polytetrafluoroethylene (PTFE) coatings for many products, including medical devices like guidewires, hypotubes, coil wires, and needles.

By 2015, companies began using short-chain perfluoroalkyl and polyfluoroalkyl substances (PFAS) as an alternative to PFOA. This seemed a viable solution until new claims emerged that PFAS was also harmful to the human body and the environment.

PFAS, which comprises literally thousands of chemicals, were labeled as forever chemicals because they break down very slowly and their use is so widespread. In early February, EU regulators proposed eliminating the use of PFAS as early as 2026, with some uses allowed to phase out over the next decade.¹ The EPA will likely follow the EU, but the question is how quickly.

Knowing how great an impact eliminating PFAS will have on life as we know it, chemical and coatings manufacturers, among others, are working hard to make the case for avoiding broad-brush-stroke type elimination.

It is a very complicated spider’s web because of the many benefits fluoropolymers offer, including the most well-known, its highly effective nonsticking and insulating properties, but also its resistance to fire, extreme temperatures, and weather.

Fortunately, there are three key organizations that are working on behalf of their member companies to educate the public and the regulatory agencies about the importance of fluoropolymers. They are the globally active Performance Fluoropolymer Partnership, the Fluoropolymers Division of the U.S.-based Plastics Industry Organization, and the Fluoropolymers Product Group of Plastics Europe.

This advocacy is essential because, currently, there are no known alternatives on the market that can match what fluoropolymers can do. Now, more than ever, it is crucial for the industry to spread the truth and dispel the myths.

PTFE: Myth vs. Truth

For purposes of this article, following are common misconceptions about the use of PFAS and PTFE in medical devices and the truths that must be told.

Myth: All PFAS are bad. According to the U.S. Centers for Disease Control and Prevention, exposure to high levels of PFAS can disrupt liver function, increase the risk of kidney or testicular cancer, reduce birth weight in infants, and negatively affect the health of pregnant women.²

Truth: Fluoropolymers are a unique group of PFAS substances that are not shown to be harmful to the body or to the environment when used as intended. The proposed PFAS ban is based on its potential to cause those problems versus having proof that they do.

Disclaimers from the CDC support this fact, saying, “At this time, scientists are still learning about the health effects of exposures to mixtures of different PFAS,” and “additional research may change our understanding of the relationship between exposure to PFAS and human health effects.”

When it comes to medical devices, for example, fluoropolymers are a critical but very small part of the PTFE coatings they help produce. Additionally, while PFAS are water soluble, the PTFE manufacturing process makes this a moot point because PTFE is inert.

Once again, chemical and coatings manufacturers in the EU and United States are working to help regulating organizations make important distinctions between PFAS substances that probably should be eliminated and those that can and should be used. There must not be a broad-brush-stroke elimination.

Myth: PTFE is dangerous if ingested or inserted into the body.

Truth: PTFE has a unique chemical structure that happens to fall under the PFAS class of substances. However, the PTFE molecule is inert and thermally stable so that if it were put into water, nothing would happen to it; and if you put it into the body, it passes through unaltered because it does not biodegrade. It is not absorbed into the body as are some PFAS chemicals.³

In the medical industry, there is a very low amount of PTFE coating applied on medical devices. For example, consider the guidewires used for cardiac procedures like angioplasties and the placement of stents in very small veins and arteries. The guidewires measure between 0.0065 and 0.015 in. in diameter (about five times thicker than a human hair), and the wire is 5-6 ft. long. The uniform thickness of most PTFE coatings that are applied to these and other medical devices ranges from 5 to 15 μm, which is extremely thin. Specifically, the amount of coating used on a guidewire is less than 0.013 oz. of coating per guidewire.

Myth: PTFE will be eliminated completely.

Truth: No one wants to completely eliminate PTFE. It is just too important to too many industries, from cookware to packaging to electric-powered cars and airplanes.

If PTFE were eliminated, the medical device industry would be set back decades because PTFE, with its unprecedented low coefficient of friction, is what makes it possible for surgeons to perform procedures with the ease and degree of safety we have all become accustomed to. Imagine delicate vascular procedures being performed before PTFE coatings were applied to the guidewires. Yet the PFAS substances that are used to make PTFE are being targeted for elimination.

While coatings manufacturers currently use PFAS to make PTFE, they are not turning a blind eye to its eventual elimination and are working to stay ahead of the curve. For example, the use of PFAS in processing PTFE coatings must be closely controlled by the processor. All water used in the process must be filtered before exiting a plant and flowing into the sewer system. The fumes produced during polymerization must be incinerated prior to being released to the atmosphere.

These preventive measures were not done previously, but many PTFE manufacturers such as Chemours and Daikin have implemented these procedures. Most other PTFE manufacturers have moved quickly in that direction.

The Drive for Sustainable Coatings

Here in the United States, the EPA is looking at the best available technology, working cooperatively with the chemical and coatings industries to learn what can be done to eliminate PFAS in favor of more sustainable, functional coatings and set a time limit to reach that goal.

The process used in 2015 for the elimination of PFOA in manufacturing is a good example of industry and the EPA working together to achieve mutual success. The EPA realized that it could not eliminate PFOA all at once, and taking valuable input provided by chemical manufacturers, set a timeline to use the best available technology back in 2010 to eliminate its use. We see the same type of collaborative process being initiated for other PFAS in the United States.

This is pretty common practice in the United States, whereas in the EU, mandates often are handed out using governmental power to say “PFAS will be eliminated by this time and that is just how it is going to be.”

Interestingly, the EU has instead opened this issue for input from the manufacturing industry, so numerous companies are contacting the European Commission to provide data supporting their need to responsibly use PFAS substances in products. Time will tell whether future EU regulations will ease as a result. Still, there are other companies, like 3M, that are getting out of the PTFE and PFAS business to avoid ongoing exposure to lawsuits.

The quest to eliminate PFAS has more than just the coatings and chemical industries reeling. Engineers and medical device designers are also undergoing a paradigm shift and rethinking how to produce devices using more sustainable PTFE coatings, along with alternatives to PTFE, that will comply with the new restrictions while ensuring that their products meet or exceed performance expectations. It is a role reversal, to be sure. OEM companies traditionally called the shots about how their products should be manufactured but are now in reactive mode under the watchful eye of the EPA and EU.

Answering Sustainability’s Call

Strides have been made, some significant, toward greatly reducing PTFE in medical device coatings. For example, through collaboration with functional coating technology companies like Surface Solutions Group (SSG), coatings manufacturers are using established scientific data to reformulate existing proven coatings to create new versions that reduce the use of restricted chemicals. All this, while at the same time meeting product performance standards and working to fill the all-too-critical supply chain gaps left by others.

With the growing concern over PTFE use in medical devices, alternatives are being examined to find lubricants that can be added to coatings that are not manufactured with PFAS nor contain PFAS.

Companies are working hard to find the right combination of resins and lubricants that can work on medical devices. One example of success occurred 10 years ago, when a coating was developed for use on nitinol wire that comprised only 5 percent PTFE. The new, low 5 percent PTFE coating has a cure temperature of 450 °F while the previously specified PTFE coating had a cure temperature of 700 °F. An additional, welcome benefit was also revealed: At the new, 450 °F cure temperature, the coating did not change the A_f of the nitinol wire.

With further R&D efforts, SSG recently discovered that it was possible to remove the remaining 5 percent PTFE and achieve the same frictional values that customers required. Upon comparing the frictional properties of this coating to resin-bonded PTFE coatings, researchers found it to be nearly equal.

SSG’s R&D work created GlideMed™, water-based, low-friction, biocompatible medical device coatings that contain no PTFE and one that is low PTFE. They are free from any PFOA, PFOS, solvent, and hex chrome compounds. These properties make them sustainable and REACH and RoHS compliant.

Where Do We Go from Here?

In terms of the medical device industry, the quest continues for more sustainable coatings. There is little doubt that PTFE coatings that are made using PFAS substances will eventually be eliminated, but it is imperative that the industry continues to educate and advocate for a cautious, gradual approach.

As this article was being written, it came to the industry’s attention that the EU MDR is reconsidering banning fluoropolymers and, namely, PFAS. This is due in large part to industry pressure, according to a recent article.⁴ The final outcome remains to be seen, but one thing is certain. Regulatory changes will continue to occur, and industry must be poised to respond.

References

1. Bloomberg Law News, “Ban on PFAS Use and Production Proposed in European Union,” Feb. 7, 2023.
2. Agency for Toxic Substances and Disease Registry, US Department of Health and Human Services , “What are the health effects of PFAS?” November 1, 2022.
3. Dechengwang Fluoropolymers, Blog, “What is PTFE: Everything You Need to Know,” May 30, 2022.
4. Arthur Neslen, “EU to drop ban of hazardous chemicals after industry pressure,” The Guardian, Tue 11 Jul 2023 01.00 EDT.

This article was written by George Osterhout, Senior Advisor and past President at Surface Solutions Group, LLC, Chicago, IL. Osterhout holds two patents and has 48 years of coatings industry experience. For more information about SSG or GlideMed™, visit here  or e-mail This email address is being protected from spambots. You need JavaScript enabled to view it. or phone 773-427-2084.

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