Commonly known by its trade name, Teflon, polytetrafluoroethylene (PTFE) is a fluoropolymer with very useful applications. Some of its unique properties include nonreactivity, hydrophobicity, a low coefficient of friction, and good insulating properties. It is most used as a nonstick coating for cookware, but it also has high-performance applications in various industries where high heat resistance, high purity, and chemical inertness are important.
One of those applications is flame retardancy in polymer formulations. Halogens, including PTFE, are often used as additives to improve flame protection in cables and other materials. However, fluorosurfactants used in PTFE production, particularly perfluorooctanoic acid (PFOA), have been associated with human health and environmental issues. The increasingly stringent regulations and standards regarding PTFE and other PFAS have led to a race to replace them with safer additives.
Now, Spain-based clay additives manufacturer Tolsa has developed a range of flame-retardant additives to replace polytetrafluoroethylene (PTFE) as an anti-dripping mechanism for polymer formulations.
In halogen and halogen-free formulations, the use of drip suppressants or anti-dripping agents is necessary. Tolsa’s new ADINS clay series products are magnesium silicates modified in their surface with organic compounds to ease dispersion in polymeric matrices. The needle-like structure reinforces the consistency of the char, improving its properties and its gas barrier capabilities, according to the company. This enhanced char decreases heat release and flame propagation and reduces smoke emissions and dripping. Key applications include wire and cable, electrical and electronics, construction (pipes, insulating foams, etc.), and transportation.
Tolsa says the ADINS series meets ‘stringent regulations as well as environmental, health and safety standards that are directly influencing the demand for alternative and safe materials’. The products’ benefits have been proven by using standard fire behaviour characterisation test methods such as UL-94, LOI, and Cone Calorimeter.