Polymeric allophanates of diphenylmethane diisocyanate, prepolymers of these polymeric allophanates, and processes for the preparation of the polymeric allophanates and the prepolymers thereof
AssigneeBayer MaterialScience AG
InventorsWilliam E. Slack, Hersel T. Kemp, II, William E. Miller
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Abstract
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%.
Claims22
A process for the production of a polymeric allophanate modified diphenylmethane diisocyanate having an NCO group content of 12 to 30% by weight, comprising:
- (I) reacting:
- (1) one or more OH-group containing compounds selected from the group consisting of:
- (a) aliphatic alcohols, (b) aromatic alcohols, (c) aliphatic diols and (d) mixtures thereof;
- and
- (2) diphenylmethane diisocyanate comprising:
- (a) from 0 to 60% by weight of 2,4′-diphenylmethane diisocyanate,
- (b) less than 6% by weight of 2,2′-diphenylmethafle diisocyanate, and
- (c) the balance being 4,4′-diphenylmethane diisocyanate, with the %'s by weight of (2)(a), (2)(b) and (2)(c) totaling 100% by weight of (2), in the presence of:
- (3) one or more allophanate catalysts, at temperatures of about 80 to about 110° C. to form (A) an allophanate-modified diphenylmethane diisocyanate;
- and
- (II) cooling (A) said allophanate-modified diphenylmethane diisocyanate to a temperature of about 20 to about 70° C. for about 1 hour to about 30 days, thereby forming (B) a polymeric allophanate modified diphenylmethafle diisocyanate.
A polymeric allophanate modified diphenylmethane diisocyanate having an NCO group content of 12 to 30% by weight, and comprising:
- (A) an allophanate modified diphenylmethane diisocyanate, having an NCO group content of 20 to 32% and which comprises the reaction product of:
- (1) one or more OH-group containing compounds selected from the group consisting of (a) aliphatic alcohols, (b) aromatic alcohols, (c) aliphatic diols, and (d) mixtures thereof;
- and
- (2) diphenylmethane diisocyanate comprising:
- (a) from 0 to 60% by weight of 2,4-diphenylmethane diisocyanate,
- (b) less than 6% by weight of 2,2′-diphenylmethane diisocyanate, and
- (c) the balance being 4,4′-diphenylmethane diisocyanate,
- with the %'s by weight of (2)(a), (2)(b) and (2)(c) totaling 100% by weight of (2), in the presence of
- (3) one or more allophanate catalysts;
- wherein (A) said allophanate-modified diphenylmethane diisocyanate is held at a temperature of from about 20 to 70° C. from about 1 hour to about 30 days to form (B) the polymeric allophanate modified diphenylmethane diisocyanate.
A polymeric allophanate modified diphenylmethane diisocyanate, having an NCO group content of 12 to 30% by weight and corresponding to the general structure:
- wherein:
- n:
- represents an integer of from 1 to 100,
- R:
- represents diphenylmethane;
- and
- x:
- represents an integer of 1 or 2;
- with the proviso that:
- when x=1,
- R1:
- represents a hydrocarbon radical containing from 1 to 36 carbon atoms, said hydrocarbon radical being selected from the group consisting of alkyl radicals, alkenyl radicals, cycloalkyl radicals, arylalkyl radicals and aryl radicals, each of which optionally contains groups that are not reactive with isocyanate groups;
- and
- when x=2,
- R1:
- represents a hydrocarbon radical containing from 2 to 16 carbon atoms, said hydrocarbon radical being selected from the group consisting of alkyl radicals, alkenyl radicals, cycloalkyl radicals and arylalkyl radicals, each of which optionally contains groups that are not reactive with isocyanate groups.
Dependencies are inferred from the claim text.