Patent ID: 6482913
Filing Date: 2002-11-19
Classification: C08G

Abstract:
A process for the preparation of a stable liquid polyisocyanate composition which is characterized by improved freeze-stability, comprising(I) reacting (A) an allophanate-modified MDI having an NCO group content of 16 to 32.5%, which comprises the reaction product of (1) diphenylmethane diisocyanate containing from about 0 to about 20% by weight of the 2,4â€²-isomer, from about 0 to about 2% by weight of the 2,2â€²-isomer, and the balance being the 4,4â€²-isomer, and (2) an aliphatic alcohol; with (B) a low molecular weight branched aliphatic dihydroxy compound comprising a poly-1,2-propylene ether glycol having a molecular weight of 134 to 700, thereby forming an allophanate-modified MDI prepolymer; and (II) adding (C) an epoxide functional compound to the allophanate-modified prepolymer, wherein the amount of (C) is such that there is from about 0.01 to 1% by weight of (C), based on the combined weight of (A) and (B).