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Halogen Free Flame Retardants

Halogen Free Biobased Fire Retardant Intumescent Coatings

Do the fire safety benefits justify the risks?

Following heightened global awareness and new regulations have prompted additive industries to invest and evaluate halogen free flame retardants. Our biomass Kraft Lignin raw material perfectly fits in as a suitable candidate to develop as a Halogen free bio-based flame retardants due to its inherent property.

Kraft Lignin

Lignin is a complex plant-derived zero PAH polymer binds cellulose and hemicellulose together, giving wood its stiffness and resistance to rotting. Every tree is holds the second biggest source of renewable carbon on the plant based on a powerful substance within the cell walls. This is extracted and converted, that holds the promise to transform the way we use our natural resources to make products. Kraft Lignin is a renewable, wood-based, non-toxic alternative to fossil-based materials.


Kraft Lignin has numerous applications across a variety of industries, including automotive, construction, coatings, plastics and pharmaceuticals.

The presence of lignin can effectively reduce the flammability of polymers such as polypropylene, PBS, ABS, PET, etc. Further, it is reported that thermal degradation of lignin generates very high amounts of char, around 35–40% .

The ability to form char during the thermal degradation is a basic aspect of flame retardant intumescent systems. Upon heating, fire retardant (FR) intumescent materials form a foamed cellular charred layer, which protects the underlying material from the action of heat flux and flame. The proposed mechanism is based on the charred layer acting as a physical barrier, which slows down heat and mass transfer between the gas and the condensed phase.

Generally, intumescent formulations contain an acid source, a carbon source and a blowing agent. Bio-based lignin act as carbon source blended with acidic source such as ammonium polyphosphate (APP), melamine polyphosphate (MPP), metal phosphinate, etc., can be used as intumescent systems for polymer to develop materials with enhanced fire retardant/fire resistant properties.

In the pursuit of non-halogenated flame retardant, lignin-based intumescent could be considered an efficient system. These FR additives are becoming more and more dominant, and in many cases are slowly replacing halogenated flame retardants.

To learn more about halogen-free bio-based flame retardants solutions, reach us for additional information.

Extracting the maximum value from biomass enhancing your business potential. The true potential of bio-based chemicals is a treasure we are working on. This can help you manufacture environmentally friendly products leading to a sustainable future. 

Our commercial lignin, tailored to your specific needs.

  • Biobased Lignin based Intumescent Coatings / Paints
  • Resins for Construction Industry
  • Asphalting for Infrastructure
  • Dyes as Dispersant
  • Bio-based chemicals, adhesives & Many Others in Development

Reach us to explore possibilities

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