EP0480588A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Continuous process for the production of isocyanate-containing polyurethane prepolymers
Assignee: Huntsman International LLC
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Filing: 1991-09-16
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Granted: —
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Expires: 2011-09-16
Abstract
Abstract A continuous process for the preparation of an isocyanate-terminated prepolymer having an NCO content in the range from 2 to 15% by weight, said process comprising the steps of : (A) continuously delivering to a reaction zone an organic polyisocyanate composition and an isocyanate reactive compound having an average molecular weight of at least 1000 the relative proportions of isocyanate composition and isocyanate reactive compound being appropriate for the formation of a prepolymer having an NCO content in the indicated range; (B) allowing the isocyanate composition and the isocyanate reactive compound to react in the reaction zone to form an isocyanate-terminated prepolymer, and (C) continuously removing the prepolymer from the reaction zone.
Inventors
- 👤 Gabriel Verhelst
- 👤 Louis Muller
- 👤 Alain Parfondry
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 03:23
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/0895; C08G18/10; C08G18/70; C08G18/72; C08G18/74; C08G18/76; C08G18/7657; C08G18/7664; C08G2110/00; C08G2110/0008; C08G2110/0041; C08G2110/005; C08G2110/0083
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
112 words
A continuous process for the preparation of an isocyanate-terminated prepolymer having an NCO content in the range from 2 to 15% by weight, said process comprising the steps of : (A) continuously delivering to a reaction zone an organic polyisocyanate composition and an isocyanate reactive compound having an average molecular weight of at least 1000 the relative proportions of isocyanate composition and isocyanate reactive compound being appropriate for the formation of a prepolymer having an NCO content in the indicated range; (B) allowing the isocyanate composition and the isocyanate reactive compound to react in the reaction zone to form an isocyanate-terminated prepolymer, and (C) continuously removing the prepolymer from the reaction zone.
Claim 2
Dependent Claim
26 words
A process according to claim 1 wherein the isocyanate reactive compound has an average nominal functionality of 2 to 3 and a molecular weight of 2000-8000.
Claim 3
Dependent Claim
25 words
A process according to any preceding claim wherein no heat is applied to the prepolymer-forming reactants or reaction mixture other than to liquefy solid reactants.
Claim 4
Independent Claim
129 words
A method for the production of flexible foams comprising the steps of : (A) continuously delivering to a reaction zone an organic polyisocyanate composition, and an isocyanate-reactive compound having an average molecular weight of at least 1000 and optionally a catalyst, the relative proportions of isocyanate composition and isocyanate reactive compound being appropriate for the formation of a prepolymer having an NCO content in the range from 2 to 15% by weight; (B) allowing the isocyanate composition and the isocyanate reactive compound to react in the reaction zone to form an isocyanate-terminated prepolymer; (C) continuously removing the prepolymer from the reaction zone; (D) delivering the prepolymer to a foam-forming zone; (E) reacting the prepolymer in the foam-forming zone with an isocyanate-reactive component and (F) recovering the foam so formed.
Claim 5
Dependent Claim
46 words
A method according to claim 4 wherein the isocyanate reactive component comprises at least 40% by weight of water, the rest of it being chain extenders, crosslinkers, conventional additives and less than 5% by weight of a conventional polyol used for the formation of polyurethane foams.
Claim 6
Dependent Claim
19 words
A method according to claim 4 wherein the isocyanate reactive component comprises at least 95% by weight of water.
Claim 7
Dependent Claim
18 words
A method according to claim 4 wherein the foam-forming reaction mixture is substantially free of halocarbon blowing agent.
Claim 8
Dependent Claim
22 words
A method according to claim 4 wherein a second isocyanate composition is delivered to the foam-forming zone in addition to the prepolymer.
Claim 9
Dependent Claim
21 words
A method according to claim 8 wherein the second isocyanate composition has an NCO content of at least 25% by weight.
Claim 10
Dependent Claim
21 words
A method according to claim 8 wherein the second isocyanate composition is delivered to the foam-forming zone independently from the prepolymer.
Claim 11
Dependent Claim
123 words
A method according to claim 4 wherein the prepolymer is prepared from a diphenylmethane diisocyanate composition and is used in conjunction with a second diphenylmethane diisocyanate composition having a NCO content of at least 25% by weight, the weight ratio of prepolymer to second MDI composition being in the range from 2.3:1 to 100:1, the prepolymer and second MDI composition together containing from 20 to 40% by weight of methylene-bridged polyphenyl polyisocyanates or reacted residues thereof and from 80 to 60% by weight of reacted residues of isocyanate-reactive species, the isocyanate reactive component comprising at least 95% by weight of water, and the weight ratio of prepolymer and second MDI species to aqueous isocyanate-reactive component being in the range from 100:10 to 100:1.
Claim 12
Independent Claim
26 words
A method according to any of the preceding claims 4-11 wherein the reaction zone to form the isocyanate-terminated prepolymer is also used as the foam-forming zone.
Claim 13
Independent Claim
22 words
A method according to any of the preceding claims 4-11 wherein the steps (D), (E) and (F) are being carried out continuously.
Claim 14
Dependent Claim
20 words
A method according to claim 13 wherein the prepolymer is continuously transferred from the reaction zone to the foam-forming zone.
References Cited (Backward Citations)
No citation records indexed.
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