Smart Coatings Continue to Develop

By Cynthia Challener

Since the topic of smart coatings was reviewed in COATINGSTECH in 2005, the field has garnered much more interest and expectations have grown regarding the commercial potential of these important materials. Advances are being made by academic, government, and industrial research groups around the world. The excitement being generated by this work will continue to propel further gains in knowledge and increase the likelihood that smart coatings technology will eventu­ally become a fundamental capability of the paint and coatings industry.

Even with all of the interest in smart coatings, it is still not obvious in some cases whether a coating is truly “intelligent.” In part because of the attention the field is receiving, many high performance coatings are claimed to be smart materials, but they do not meet the proper criteria.

Smart coatings sense and respond to changes in the environment or within themselves, preferably in a re­versible manner. Changes in light, temperature, pres­sure, air flow, surface tension, electrical current, acidity, chemical composition, and bioactivity, among others, cause the coating to undergo some sort of transforma­tion. Once the stimulus is removed, the coating ideally returns to its original form.