Chemie Linz Aktiengesellschaft

Chemiefaser Lenzing Aktiengesellschaft

Gerhard Stern

Wilhelm Dobramysl

Klaus Weinrotter

Karlheinz Wegleitner

Walter Raml

Herbert Greinecker

Acetonitrile and molten sodium are reacted at a temperature of 96.degree.-140.degree. C. in the presence of an organic solvent which is inert to sodium, to give the sodium salt of diacetonitrile, the salt is hydrolyzed with water, the aqueous and the solvent phases are separated off, and very pure diacetonitrile crystallizes out in cold water.

Process for preparing pure diacetonitrile

A polyacrylonitrile fiber which has flame-retardant properties, is produced by dry spinning, has an acrylonitrile content of at least 85% by weight in the parent polymer and contains as flame retarder 15 to 40% by weight of tris-2,3-dibromopropyl isocyanurate, based on the polymer. The flame-retardant effect can be further increased by a content of up to 10% by weight of one or more synergistic compounds.

Flame-retardant polyacrylonitrile fiber

Process for the preparation of monomeric methylolmelamine which is partially etherified with methanol or ethanol and which contains at least 4 moles of formaldehyde per mole of melamine, by reacting melamine, paraformaldehyde and methanol or ethanol in a single stage reaction, the molar ratio of melamine to formaldehyde to alcohol being 1:5 to 10:6 to 20, in a virtually anhydrous medium, under a nitrogen atmosphere, at a pH of 7 to 8 and a temperature from 50.degree. to 90.degree. C. and with a reaction time of from 3 to 30 hours.

Process for the preparation of partially etherified methylolmelamines

A filler for paper, card or board which has a good retention and consists of an inert core material and a hydrophilic coating, which consists of polyacrylamide having a molecular weight of 10.sup.5 to 10.sup.7 or of a mixture of this polyacrylamide with a urea-formaldehyde condensation resin. The filler is prepared by suspending the inert core material in an aqueous solution of a polyacrylamide having a molecular weight of 10.sup.5 to 10.sup.7 or in an aqueous solution of such a polyacrylamide and a urea-formaldehyde condensation resin, and drying this suspension by spray drying or in a stream of hot air. This crosslinks the initially water-soluble polymer and forms a coating, adhering to the core, which is insoluble in water but is hydrophilic and swells, and becomes tacky, in the presence of water.

Filler for paper, card or board, a process for its manufacture, and

A storage-stable lacquer resin which can be baked without yellowing at a low baking temperature, and is based on an alkyd resin, acrylic resin or epoxy resin, is obtained by reacting the resin with a bis- or tris-alkoxyalkylamino-s-triazine which has been obtained by heating a triazine derivative of the general formula: ##STR1## wherein X is an alkyl group having 1 to 4 carbon atoms, a phenyl group or the group ##STR2## and each of R and R' is an alkyl group radical having up to six carbon atoms, at 100.degree. to 200.degree. C. up to a weight loss of 3 to 25%, preferably 5 to 15%.

Storage-stable lacquer resins

Foamed plastics with improved combustion characteristics are produced by condensing an aqueous solution of formaldehyde-urea and/or melamine precondensates with polyisocyanates and optionally a polyol in the presence of an acid catalyst, being present in an amount of 1 part by weight per at least 20 parts by weight of precondensate, whereby this catalyst is added to the isocyanate before mixing with the precondensate or to the mixture of isocyanate and precondensate, but separately from the precondensate.

Growing community of inventors

Linz, Austria

Gerhard Stern