Dicyandiamide (DICY, Coarse Grade)

Dicyandiamide (DICY) Coarse Grade is the standard industrial form of dicyandiamide with a particle size of d50 approximately 30–50 µm, used in epoxy powder coatings, thermosetting molding compounds, and other applications where fine particle size is not required. The coarse grade is more cost-effective than the fine grade and is used in applications where the DICY is dissolved into the epoxy at elevated temperature during processing (rather than remaining as a solid dispersion at ambient). In epoxy powder coatings, DICY is melted and dissolved into the epoxy resin during extrusion at 90–110°C, ensuring complete dissolution and uniform distribution before the powder is ground. In thermosetting epoxy molding compounds (B-staged solid or semi-solid compounds), coarse DICY is incorporated during hot mixing at 60–100°C. The coarse grade also serves as a flame retardant synergist in halogen-free flame retardant epoxy formulations. Typical dosage is 4–7 phr on BPA epoxy resin. Used with imidazole or uron accelerators for practical cure times at 120–180°C. The coarse grade has the same chemical purity (≥99%) and latent curative chemistry as the fine grade.