Sustainable & circular coatings: A formulator's approach to material selection

Coating formulators used to choose raw materials based on performance, cost, and processability. This is changing. Today, formulators are under pressure to reduce volatile organic compounds (VOCs) and hazardous air pollutants (HAPs). They must also avoid substances under increasing regulatory scrutiny [e.g., heavy metals, alkylphenol ethoxylates (APEOs), and PFAS]. 

The goal is to improve worker and consumer safety and meet customer sustainability commitments. What was once a downstream Environmental, Health, and Safety (EHS) discussion now shapes binder choice, additive selection, pigment package design, and cure schedule.  

Three forces are driving this shift. 

1. Regulatory push: Regulations continue to tighten around emissions, hazardous chemistry, and reporting obligations. Formulation space is influenced by VOC limits, HAPs, heavy metals, PFAS restriction/reporting activity, and increasing attention to safer chemistry.
2. Market pull: Brand owners, driven by their stakeholders, ask the supply chain for lower-carbon, lower-hazard, or recycled-content solutions. OEMs, consumer brands, and building-product companies translate corporate sustainability goals into purchasing specifications for coatings and raw materials.
3. Operational strategies: Rising raw material cost and energy volatility have made “Reduce, Reuse, and Recycle” a commercial issue as much as an environmental one. Lower bake temperatures, fewer application passes, and higher transfer efficiency can reduce both the footprint and the total applied cost. 

Sustainable vs. Circular: What do they mean in paints and coatings?

Sustainable coatings function with a lower environmental and human-health burden across their life cycle. This can mean lower VOC, reduced hazard, renewable or bio-based feedstocks, lower embedded carbon, lower energy consumption, or better durability that extends service life.  

Circular coating goes one step further. It is selected not only for lower impact during manufacture and use, but also for what happens to the coating material or the coated object later. A circular design avoids contaminating recycling streams and allows separation when needed. It supports repair and refurbishment while minimizing irreversible combinations of materials.

Recyclability is a key component of circularity. In paints and coatings, it has two distinct aspects:

• Substrate recyclability: The ability to recover and reuse coated materials such as metals, wood, etc.
• Coating material recyclability: The ability to process off-spec, unused, off-tinted paint returned from store closure, brand discontinuation, etc. These can be recycled to make similar or different types of paints or coatings that meet industry standards.

While sustainability and circularity are related, it is important to recognize their difference. For example, a highly durable coating may be sustainable in terms of service life. However, it may not be circular if it generates hazardous byproducts or introduces incompatible components into a recycling stream. 

Also, “bio-based” does not automatically mean “circular,” and “recyclable” does not necessarily make the coating sustainable. 

Sustainability and circularity overlap but are distinct design objectives