摘要:
Allophanate-modified 1,3-phenylene diisocyanates or 1,1-biphenyl diisocyanates or 1,1'-oxy-bis-(isocyanato benzenes) which are storage stable liquid at 25.degree. C. are made by reacting the diisocyanate and a mono-alcohol to form an isocyanate containing urethane groups. The urethane groups in the diisocyanate are then converted to allophanate groups. The resultant product which has an isocyanate group content of from about 10 to about 40% may be further reacted with isocyanate-reactive compounds to produce an allophanate-modified diisocyanate prepolymer containing urethane or urea groups having an isocyanate group content of from about 5 to about 40.0%. The liquid, storage-stable, allophanate-modified diisocyanates produced by these processes are particularly useful in the production of elastomers and flexible foams.
摘要:
Ether-linked amine-terminated polyethers are produced by reacting (1) a polyether polyol in which substantially all of the hydroxyl groups have been replaced with good leaving groups with (2) an aminoalcohol and/or aminothiol and (3) a deprotonating agent. The aminopolyethers obtained by this process are characterized by low viscosities and excellent reactivities over a wide range of molecular weights and functionalities.
摘要:
Disclosed herein is a liquid isocyanate prepolymer having an isocyanate group content of from 10 to 30% by weight, prepared by reacting:i) a polyfunctional secondary amine group containing material of the general formula: ##STR1## wherein R represents alkyl, alkenyl, cycloalkyl, aralkyl or aryl radical:A represents an organic radical having a molecular weight between 28 and 6000 and having a functionality of m andm represents an integer from 2 to 6;withii) an isocyanate mixture comprising:a) from 50 to 100% by weight of diphenylmethane diisocyanate of which from 2 to 50% by weight consist of 2,2'- and 2,4'-isomers; andb) the balance being polyphenylpolymethylene polyisocyanates.
摘要:
This invention relates to liquid polyisocyanate compositions having improved freeze stability. These liquid polyisocyanate compositions have an NCO group content of 15 to 30%, and comprise a blend of (A) an MDI adduct having an NCO group content of 15 to 30%, and (B) an allophanate-modified MDI having an NCO group content of 12 to 32.5%.
摘要:
This invention relates to liquid polyisocyanate compositions having improved freeze stability. These liquid polyisocyanate compositions have an NCO group content of 15 to 30%, and comprise (A) an allophanate-modified MDI and having an NCO group content of 16 to 32.5%, (B) a low molecular weight branched aliphatic dihydroxy compound, and (C) an epoxide functional compound which is present in an amount of 0.01 to 1% by weight, based on the combined weight of components (A) and (B).
摘要:
This invention relates to mixtures of urethane prepolymers of allophanate-modified diphenylmethane diisocyanates with epoxides. The addition of the epoxide increases the reactivity of these prepolymers. It is now possible to form polyurethanes from these mixtures based on prepolymers of diphenylmethane diisocyanates wherein less catalyst is necessary.
摘要:
TDI residue-based urethane-filled isocyanate compositions are produced by reacting a TDI residue satisfying specified criteria with a monofunctional alcohol in amounts such that the equivalent ratio of isocyanate groups to hydroxyl groups is from about 0.9:1 to about 1:0.9. This reaction product is then dissolved in a diisocyanate or polyisocyanate before, during or after reaction of that product with an epoxide having an epoxide equivalent weight of from about 44 to about 400 at a temperature of up to 120.degree. C. These TDI residue-based urethane-filled isocyanate compositions are particularly useful in the production of polyurethanes.
摘要:
This invention relates to a process for the preparation of a flexible foam. This process comprising reacting a liquid, storage stable, allophanate-modified polyisocyanate having an NCO group content of about 20 to about 42%, with an isocyanate-reactive component, in the presence of a blowing agent and at least one catalyst, wherein the relative amounts of the polyisocyanate and the isocyanate-reactive component are such that the NCO index if from about 70 to about 130.
摘要:
The present invention relates to a new high functionality MDI. In particular, this invention relates to polymeric allophanates based on diphenylmethane diisocyanate having an NCO group content of 12 to 30%, prepolymers thereof, and processes for the production of these compositions. The prepolymers are stable liquids having NCO group contents of about 10 to about 28%.
摘要:
This invention relates to a novel freeze-stable allophanate modified toluene diisocyanurates, and to a process for producing these freeze-stable allophanate-modified toluene diisocyanurates which requires a catalyst which is capable of forming both trimer and allophanate groups, or a catalyst system comprising at least one catalyst capable of forming trimer groups and at least one catalyst capable of forming allophanate groups. This invention also relates to novel freeze-stable blends of the allophanate-modified toluene diisocyanurates with di- and/or polyisocyanates of the diphenylmethane series; and to freeze-stable urethane prepolymers of the allophanate-modified toluene diisocyanurates, or the blends of these with an isocyanate of the diphenylmethane series.