Expandable Graphite CAS 7782-42-5

FAQ - Technical & Supply Chain

• Q:

  What is Expandable Graphite CAS 7782-42-5?

  A: Expandable Graphite is a graphite-based intercalated material, not a single small-molecule chemical. CAS 7782-42-5 identifies the graphite base material, while expansion performance is controlled by the intercalation treatment, particle size, and commercial grade.
• Q:

  How does Expandable Graphite work as a halogen-free flame retardant?

  A: When exposed to heat, the graphite layers expand and create a low-density insulating carbon layer. This layer helps reduce heat transfer, limit flame spread, and protect the underlying polymer or substrate without relying on bromine or chlorine.
• Q:

  Which parameters should buyers evaluate when selecting a grade?

  A: The most important parameters are expansion volume or expansion ratio, particle size distribution, carbon content, sulfur content, and expansion onset temperature. The selected combination should be matched to the polymer, coating, foam, or sealing system and its processing conditions.
• Q:

  Can Expandable Graphite be used in fire-resistant coatings and sealing materials?

  A: Yes. It is used in intumescent coatings, firestop materials, gaskets, sealing strips, and insulation systems. In these applications, the expansion behavior and particle size are especially important because they affect film quality, sealing performance, and thermal protection.
• Q:

  Why do some formulations require low-sulfur Expandable Graphite?

  A: Sulfur can cause corrosion, odor, or compatibility problems in certain metal-contact, electronic, or sensitive polymer systems. Low-sulfur and super-low-sulfur grades reduce these risks, but the exact sulfur limit should be selected according to the final application and performance requirements.