16.08.2022 by Aileen Sammler

Expandable Graphite: A Sustainable Solution for Flame Retardants in Plastics

Flame retardants (FRs) have been used for decades to reduce or even eliminate the risk of fire hazards in plastic components for such applications as the electronics or automotive industries. Expandable graphite, which most only associate with increased thermal and Condutividade Elétrica (SBA)Electrical conductivity is a physical property indicating a material's ability to allow the transport of an electric charge.electrical conductivity, can also be utilized to increase fire safety.

Flame retardants (FRs) have been used for decades to reduce or even eliminate the risk of fire hazards in plastic components for such applications as the electronics or automotive industries. The most important initiative right now is the EU’s Green Deal, which will result in strong opportunities and, potentially, obligations to transition to halogen-free FRs. This will be even more likely when the anticipated revision of the RoHS (Restriction of Hazardous Substances) takes place.

There is a variety of different solutions and numerous FR polymers available on the market. One of them is expandable graphite, which most only associate with increased thermal and electrical conductivity. Its unique properties can also be utilized to increase fire safety.

Figure: NETZSCH Taurus Cone Calorimeter TCC 918

 

 

 

To highlight the effect of different amounts of expandable graphite as a flame retardant on the fire behavior of polyethylene, samples of the different compounds were injection-molded and tested in the NETZSCH Taurus Cone Calorimeter TCC 918

The instrument allows for the determination of the heat release, mass loss and density and composition of the smoke gas.

This study shows that expandable graphite is a suitable flame retardant for polyethylene (PE) and that, within the range of FR content levels investigated here, it is possible to increase the effect by using higher amounts of FR.

 

Please find more information about the Cone Calorimeter TCC 918 on our website.

 

Learn more about how the TCC 918 works in our NETZSCH ONLINE ACADEMY (NOA) course – free of charge: 

NETZSCH-Academy – The TCC 918 Cone Calorimeter