Expandable Graphite for Flame Retardant Application

Expandable graphite is a processed graphite material designed for use as a flame retardant additive in industrial applications. Upon exposure to elevated temperatures, the material expands significantly and forms an insulating carbon layer. This expanded structure can reduce heat transfer and contribute to limiting flame propagation, without the use of halogenated flame retardants.

Expandable graphite is produced from natural graphite flakes through a controlled intercalation process. When exposed to heat, the intercalated compounds decompose, causing the graphite layers to expand and form an intumescent structure that can act as a thermal barrier.

• Expansion Behaviour: Expansion volume in the range of 20 to 650 cm³/g, depending on grade and test conditions

• Intumescent Effect: Formation of a porous carbon structure that can reduce heat transfer and restrict oxygen access

• Halogen-Free: Does not contain intentionally added halogenated flame retardants

• Thermal Resistance: Suitable for applications requiring performance at elevated temperatures

• Electrical and Thermal Conductivity: Inherent to graphite, dependent on formulation and orientation

• Bulk Density: Typically 0.8–1.2 g/cm³ (unexpanded material, depending on grade)

• Chemical Stability: Resistant to many chemicals under standard processing and application conditions

Expandable graphite is supplied in compliance with applicable chemical regulations, including REACH (EC) No. 1907/2006. All supplied grades are compliant with RoHS requirements.

• Raw Material Selection: Natural graphite flakes selected based on purity and particle size and individual propreties

• Intercalation: Treatment with intercalating agents (commonly sulfur-based systems)

• Washing and Neutralization: Removal of residual reagents

• Drying and Classification: Adjustment to required particle size ranges

• Quality Control: Testing for expansion volume, particle size distribution, moisture, and chemical parameters

Expandable graphite is used as a functional additive in various systems:

• Polymer Compounds: Used in thermoplastics and elastomers for flame retardant formulations

• Foams: Applied in insulation and cushioning materials

• Sealing Materials: Used in gaskets and fire protection seals

• Intumescent Coatings: Active component in fire protection coatings

• Battery Systems: Used in thermal management concepts

• Electrical Components: Applied where combined conductivity and flame retardancy are required

Compared to other flame retardant systems:

• Versus Halogenated Systems: Does not rely on halogen chemistry, may reduce formation of corrosive gases depending on formulation

• Versus ATH: Typically used at lower loading levels, depending on formulation requirements

• Versus Vermiculite: Higher expansion potential, depending on grade

• Based on natural graphite

• Generally regarded as inert under normal conditions

• Standard industrial handling precautions apply

• Environmental and safety performance depends on the full formulation and application

Store in dry conditions and avoid moisture uptake. Use appropriate dust control measures during handling. Follow standard industrial hygiene practices.

• Carbon Content: ≥90%

• Expansion Volume: 20 to 650 cm³/g

• Onset Expansion Temperature: 150 to 280°C (grade dependent)

• Particle Size: Available in various ranges (e.g. – 45 to + 500 µm)

• Moisture: ≤1.0%

• pH: Typically 5–8

All values are typical and subject to variation depending on grade and production batch. Performance must be evaluated in the final application.

For technical information, pricing or samples, please contact us.