PFAS-free coatings: Selecting the right alternatives and managing trade-offs

Per- and polyfluoroalkyl substances (PFAS) are a class of synthetic organofluorine substances known for their strong carbon–fluorine bonds. These bonds make PFAS highly stable and resistant to breakdown.

According to the Organization for Economic Co-operation and Development (OECD), PFAS are a broad class of substances containing at least one fully fluorinated methyl or methylene carbon.

PFAS have been used for over 90 years and include a wide range of substances. Their key features include:

• Strong carbon–fluorine (C–F) bonds, among the strongest in chemistry
• High resistance to heat, water, and oil
• Long-lasting presence in the environment

Because of this extreme stability, PFAS are often called “forever chemicals.”

Perfluorooctanesulfonic acid (PFOS) - A typical PFAS

What makes them unique is summarized in the table below.

Why are they so effective in coatings?

PFAS perform well because of their unique structure:

• The carbon–fluorine bond is one of the strongest in organic chemistry
• This bond provides excellent chemical and thermal stability
• Fluorinated chains repel both water (hydrophobic) and oil (oleophobic)
• They create very low surface energy, which improves coating behavior

Because of these properties, PFAS can:

• Wet difficult surfaces, even at low doses
• Resist oily contamination
• Reduce sticking between coated surfaces
• Maintain smooth, low-friction finishes
• Create easy-to-clean surfaces

In addition, PFAS resist heat, sunlight, and oxidation. This makes them highly durable and ideal for outdoor coatings with long service life.

In coatings, PFAS fall into two main categories:

1. Fluorosurfactants (Short-chain, non-polymeric PFAS)

Fluorosurfactants are low-dose additives used to improve coating performance. They help:

• Reduce surface tension
• Improve wetting and leveling
• Prevent surface defects (like craters)
• Reduce blocking (sticking between coated surfaces)
• Improve dirt pickup resistance
• Add some oil repellency

Example: Perfluorobutanesulfonic acid

2. Fluoropolymers

Fluoropolymers are used as binders or topcoat resins when high performance is required. They are used for coatings that need:

• High weather resistance
• Strong UV protection
• Chemical resistance
• Anti-graffiti properties
• Good electrical insulation (dielectric performance)
• Low friction surfaces

Examples: Polytetrafluoroethylene (PTFE) and Polyvinylidene fluoride (PVDF)

PFAS materials exhibit a unique combination of highly desirable performance properties. This raises the question: what is the underlying concern with their use?

The core issue is their extreme persistence, driven by the strength of the C–F bond, one of the most stable in organic chemistry. This makes these substances highly resistant to thermal, chemical, and biological degradation. 

As a result, PFAS used in coatings (e.g., fluorosurfactants or residuals from fluoropolymers): 

• can accumulate in the environment and in biological systems
• have been associated with toxicity, bioaccumulation, and long environmental half-lives

In practical terms, even low use levels can lead to long-term environmental release during:

• application,
• weathering, or
• disposal

This creates regulatory and liability concerns. Thus, the same chemistry that makes them durable in service also makes them persistent. It is the central technical contradiction driving the shift toward PFAS-free alternatives.

Current regulatory landscape

Globally, regulation is shifting from managing individual PFAS substances to restricting the entire class. This is becoming a primary driver for coatings formulators to adopt PFAS-alternative technologies.

In the European Union, the proposed universal PFAS restriction under REACH Regulation could significantly limit the use of fluorosurfactants in paints and coatings. This may also affect certain fluoropolymer applications depending on derogations, with phased bans and transitional periods under active evaluation.

In the United States, the Toxic Substances Control Act (TSCA) is being used by the U.S. EPA to:

• mandate PFAS reporting,
• expand Significant New Use Rules (SNURs), and
• increase scrutiny on new and existing PFAS chemistries

Parallel state-level regulations are restricting PFAS in specific product categories. They are moving toward broader disclosure and eventual prohibitions. Some state-level regulations notably include California, Maine, and Minnesota.

It is important to note that, as of now, no major fluoropolymers such as PTFE, PVDF, FEVE, PFA, or FEP are explicitly restricted under either U.S. EPA or REACH.

Looking ahead, the key regulatory hurdle is not just compliance with current limits but:

• anticipating class-based bans,
• reporting obligations, and
• supply-chain transparency requirements

All this creates legal and commercial risk for PFAS-containing coatings, accelerating their transition to PFAS alternatives.