Melamine → Melamine formaldehyde

Participants

Reaction Steps

To 5 g of melamine powder, 6.5 g of 37% formaldehyde water solution and 10 g of water were added to be adjusted to pH 8. The resultant mixture was heated to about 70° C., whereby melamine-formaldehyde initial mixture (prepolymer) water solution was obtained. To 100 g of sodium salt water solution of styrene-maleic anhydride copolymer adjusted to pH 4.5, a mixture liquid containing 58 g of hexadecane as a phase change material 1 dissolved therein was added under vigorous stirring and emulsification was allowed to proceed until the particle diameter became 7 μm approximately. To this emulsified water solution, the entire amount of the above-described melamine-formaldehyde initial mixture water solution was added and stirred at 70° C. for 2 hours and then adjusted to pH9 for capsulation. By this capsulation process, there was obtained dispersion 3a of heat storage capsules 3 containing hexadecane as the phase change material 1 within outer shells formed of the melamine resin. After completion of the reaction, the heat storage capsules 3 were spray-dried, whereby a plurality of heat storage capsules 3b in the form of powder having a particle diameter of about 7 μm were obtained.

Provenance & Evidence