Melamine → Melamine cyanurate

Participants

Reaction Conditions

Reaction Steps

In a Henschel mixer having an internal capacity of 10 liters, 2.0 kg of industrial melamine (product of Mitsui Toatsu Chemicals Inc., melting point: 354° C., sublimation starting temperature: 210° C., average particle size: 20 μm) and 2.0 kg of cyanuric acid ("ICA-P", trade name; product of Shikoku Kasei Corp.; melting point: 360° C., sublimation starting temperature: 230° C., average particle size: 80 μm) were charged, followed by mixing at room temperature for 10 minutes. Using a jet mill, the mixture was continuously fed in its entirety at 33.4 kg/hr and room temperature so that 3.91 kg of a comminuted mixture were formed. The average particle size of the comminuted mixture was 3.94 μm (as determined based on volumes measured by the laser beam diffractometry). After 78.25 g of the comminuted mixture were placed in an evaporating dish, its surface was covered by an aluminum foil. The evaporating dish was then placed in an electric furnace, in which the comminuted mixture was heated at 350° C. for 1 hour to obtain 74.99 g of melamine cyanurate. Its yield, purity and average particle size were 95.8%, 99.2% and 4.83 μm, respectively. A differential thermal analysis curve of the melamine cyanurate so obtained is shown in FIG. 1. Incidentally, differential thermal analysis curves of the starting materials, that is, of the melamine and cyanuric acid are illustrated in FIGS. 3 and 4, respectively.

Provenance & Evidence