Christoph Irle

SYNTHESIS AND THERMOTROPIC PROPERTIES OF NEW DISCOTIC 1,3,5-TRISUBSTITUTEDS-TRIAZINETRIONES OBTAINED BY CYCLOTRIMERIZATION OF ISOCYANATES

Abstract The synthesis of a number of s-triazine-2,4,6-triones (isocyanurates) by cyclotrimerization of 4-monoalkoxy-, 3,4-dialkoxy-, or 3,4,5-trialkoxyphenyl-, benzyl-, or styryl-isocyanates is reported. The thermal and phase behaviour of the novel compounds were investigated by optical polarized light microscopy and thermal analysis. No mesophase could be observed for any of the precursors except 4-decyloxybenzoic acid. Mesophases of the isocyanurates were observed only in the series containing 3,4-dialkoxyphenyl moieties. A vinylene group between the inner s-triazine ring and the outer phenylene rings gives low melting points and enantiotropic mesophases for C8 and longer alkyl chains. The phenylisocyanurates may exhibit a monotropic mesophase and normally have the highest melting points of the three types, whereas a methylene spacer suppresses formation of a mesophase. According to the textures observed, the mesophases are hexagonal columnar. This will have to be confirmed by X-ray scattering techniques.

Neue Dispersionen für wässrige 1K- und 2K-PUR-Lacke

Mit der aktuellen Generation von Polyurethan-und Polyacrylat-Dispersionen lassen sich wassrige Lacke herstellen, die losemittelbasierten Systemen in nichts nachstehen: Als Grundierungen oder Einschichtlacke etwa schutzen sie Metall vor Korrosion, als Decklack widerstehen sie allen auseren Einflussen.