A PROCESS FOR THE PREPARATION OF LIQUID STORABLE ORGANIC ISOCYANATES CONTAINING CARBODIMIDE AND/OR URETONE IMINE GROUPS AND THEIR USE FOR THE PREPARATION OF POLYURETHANE PLASTICS

摘要

The present invention relates to liquid storable organic isocyanates containing carbodiimide and/or uretone imine groups prepared by (a) partially carbodiimidizing isocyanate groups of an organic isocyanate with catalysts of the phospholine type, and (b) terminating the carbodiimidization reaction by the addition of a silylated acid corresponding to the formula X-[Si(CH3)3]n in which X represents the neutral acid residue obtained by removal of the acidic hydrogen atoms from an n-basic acid having a pK a value of at most 3, other than a hydrohalic acid, and n is an integer of 1 to 3. The invention further relates to the use of the liquid polyisocyanate mixtures according to the invention for the preparation of polyurethane plastics, preferably polyurethane foams, having improved burning behavior.