PROCESS FOR THE MODIFICATION OF THE CRYSTAL FORM OF DICYANDIAMIDE

摘要

Process for the modification of the crystal form of dicyandiamide The present invention provides a process for the modification of the crystal form of dicyandiamide, wherein dicyandiamide is crystallised from aqueous solution in the presence of 0.001 to 1% by weight of polyvinyl alcohol and/or of a water-soluble cellulose ether derivative, referred to the amount of dicyandiamide. The crystalline dicyandiamide obtained in this manner has outstanding flow and storage properties and its mechanical strength is substantially improved.