PROCEDIMIENTO PARA LA PREPARACION DE ISOCIANATOS ORGANICOS LIQUIDOS, ESTABLES AL ALMACENAMIENTO, QUE PRESENTAN GRUPOS CARBODIIMIDO Y/O URETONIMINO, Y SU USO PARA LA FABRICACION DE PLASTICOS DE POLIURETANO

• Main Authors: WELTE, RAINER, SCHOLL, HANS JOACHIM
• Format: Patent
• Language: Spanish
• Published: 01.10.1997
• Edition: 6
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; COMPOSITIONS BASED THEREON; HETEROCYCLIC COMPOUNDS; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC CHEMISTRY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

GRUPOS LIQUIDOS, ESTABLES A LARGO ALMACENAMIENTO URETONIMINO Y/O CARBODIIMIDO QUE SE COMPONEN DE ISOCIANATO ORGANICO SE FABRICAN A TRAVES DE UN PROCESO PARCIAL DE CARBODIIMIDIZACION A PARTIR DE GRUPOS ISOCIANATOS CON CATALIZADORES DEL TIPO FOSFOLIN, DONDE LA REACCION DE CARBODIIMIDIZACION SEPARA A TRAVES DE LA ADICION DE UN ACIDO DE LA FORMULA X -[ SI (CH3)3 ] N, DONDE EN LA FORMULA X ES UN RESTO ACIDO NEUTRAL, COMO SI FUERA OBTENIDO A TRAVES DE LA ELIMINACION DEL ATOMO DE HIDROGENO ACIDO A PARTIR DE UN ACIDO N DONDE SE APARTAN LOS HIDRACIDOS HALOGENOS Y N UNA CIFRA COMPLETA DE 1 HASTA 3. ESTOS POLISOCIANATOS SON UTILIZADOS PARA LA FABRICACION DE MATERIAL SINTETICO POLIURETANO. Fluid and storage-stable organic isocyanates containing carbodiimide and/or uretonimine groups are prepared by partial carbodiimidisation of isocyanate groups with phospholine-type catalysts, after which the carbodiimidisation reaction is stopped by adding a silylated acid of the formula X-[Si(CH3)3]n, in which   X represents the neutral acid radical as it is obtained by removal of the acidic hydrogen atoms from an n-basic acid having a pKa value of not more than 3, with the exception of hydrohalic acids, and   n represents an integer from 1 to 3. These polyisocyanates are used for the preparation of polyurethane plastics.