NeoGraf Solutions, a leading developer and manufacturer of high-performance natural and synthetic graphite sheets and powders, announces the addition of GrafGuard® 280-50N to its lineup of graphite flake, non-halogenated fire retardant additives.
Designed for materials including plastics, roofing and other construction and building materials, the new GrafGuard 280-50N is specifically targeted toward the thermoplastics industry, especially specialty polymers with high processing temperatures including composites and multi-functional systems with high melting points for both injection molded and thermoformed applications.
With a particle size of 50 mesh or 300 microns, GrafGuard 280-50N has an on-set temperature of 280°C (536°F), the highest on-set temperature on the market – significantly higher than any other product offering. GrafGuard allows customers the freedom to process materials at higher temperatures to take advantage of the intumescence provided by the GrafGuard family of products to form a large, thick char layer protecting the base polymer from the heat of the flames. There is no reaction below 280°C (536°F) with no volatile loss and no visible puffing.
“While this is not all encompassing for all polymer systems, the new GrafGuard 280-50N offers a much wider range than our previous products,” said David Stuart, Research Scientist for NeoGraf.
Existing GrafGuard customers using a material dryer system to remove excess moisture or solvent from their systems often find the drying temperature is the maximum processing temperature which limits the grades of GrafGuard graphite they can use. “If they need to dry the material at very high temperatures to drive off solvent or quickly drive off moisture, they can use a higher temperature if they switch over to the new GrafGuard 280-50N material,” explained Stuart.
Depending upon the polymer system, the processing temperatures have to be higher than the melt temperature of the polymer so many thermoplastics are processed above 220°C (428°F), which can be problematic for the company’s previous high temperature material GrafGuard 250-50N. The new GrafGuard 280-50N material is much more latent at these temperatures and above to about 280°C (536°F). This will allow the customer to use typical processing parameters and simply add the GrafGuard 280-50N as an active additive.
This material is entering a new market, thermoplastics, and as there are not any graphite additives in this market due to the fact that these additives would not work due to the high processing temperatures. “There are some chemicals that can compete with the materials, but most of the traditional fire retardant chemicals react around 250°C (482°F), so they would be difficult to incorporate into to high temperature applications,” Stuart said. “The primary exception would be magnesium hydroxide, which we recommend as a synergistic material to be used with GrafGuard 280-50N.”
Markets that could benefit from the properties of the GrafGuard 280-50N include aerospace and mass transit, and any other market where that need the benefits of flame retardancy.