Researchers at the University of Texas in Austin have developed a new flame-retardant substance based on a natural chemical used by mussels. Flame retardants are a coating added to manufactured materials that can stop or delay the spread of fire. They are used in the textile, computer, and construction industries, but most traditional flame retardants are highly toxic. This study, published in Chemistry of Materials, is an important breakthrough in creating non-toxic flame retardant materials.
While the coating doesn’t usually come into contact with people, over time the flame retardants can degrade into equally toxic chemicals that have the ability to spread through products until they contaminate individuals and the environment. In 2010, a group of 145 prominent scientists from 22 countries signed the first ever consensus documenting the health hazards of flame retardant chemicals.
The new non-toxic flame retardant is based on dopamine, a compound present in animals. In humans, dopamine is a neurotransmitter and a precursor of other substances like adrenaline.
The synthetic substance they developed is called polydopamine, and its natural counterpart is used by mussels to stick to surfaces. Even the non-stick Teflon is no match for polydopamine. The substance has been studied extensively for technological and health-related applications, but the UT Austin team were the first to investigate its flame-retardant properties. It came as a surprise to the team that polydopamine is naturally flame retardant.
The researchers observed up to a 67% reduction in peak heat release rate (a measure of fire intensity) when a coating of polydopamine was applied to polyurethane foam, which is used, for example, in automobile seats and dashboards. This result is significant, as the heat release rate is considered the most important variable in fire hazards.
The polydopamine compound's ability to reduce a fire’s intensity is around 20% better than flame retardants currently in use. The coating absorbs the molecules released by burning materials, inhibiting fires from taking hold on the coated object.
“We believe polydopamine could cheaply and easily replace the flame retardants found in many of the products that we use every day, making these products safer for both children and adults,” said Professor Christopher Ellison, who led the team to this discovery, in a statement.
You can see the polydopamine being tested in the clip below:
Top Imafe Credit: Zebra mussels, 1082492116/Shutterstock.