Blocking Harmful Chemicals: The Power of Sealants on Concrete

Concrete structures can be a source of environmental trouble, especially when they come into contact with harmful chemicals like PFAS. These chemicals, often found in firefighting foams, can stick around in concrete and pose risks to the environment. To tackle this issue, researchers explored the use of sealants to prevent PFAS from leaking out of concrete. In a lab setting, six different sealants were put to the test. The standout performer was an epoxy polymer sealant, which excelled at containing PFAS within the concrete. This sealant proved to be highly effective in preventing the harmful chemicals from escaping and causing further contamination. Two bitumen-based sealants also showed promising results, but they come with their own set of challenges. These sealants are flammable and have poor light reflection properties, making them less suitable for indoor applications. Despite these drawbacks, they can still be considered for specific outdoor uses where their advantages outweigh the disadvantages. Additionally, two polymer-based sealants, acrylic and polyaspartic, demonstrated good performance in containing PFAS. Polymer-based sealants, including epoxy, acrylic, and polyaspartic, are known for their durability and resistance to chemicals, weather, UV rays, and water. These properties make them excellent choices for protecting concrete from various environmental factors. The benefits of sealants go beyond just containing PFAS within the concrete. Epoxy and polyaspartic sealants, in particular, can also help prevent the spread of PFAS to other areas. This makes a combination of surface and penetrative sealants a potentially effective strategy for managing PFAS-contaminated concrete, regardless of its age. However, it's important to note that not all sealants are created equal. The effectiveness of a sealant can vary depending on the specific situation and the type of concrete involved. Therefore, careful consideration must be given to selecting the most appropriate sealant for each unique case to ensure the best possible protection against PFAS contamination.