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US4476054A
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Uretidione dimer of isophorone diisocyanate and method of preparation
Assignee: Huels AG
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Filing: 1981-08-13
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Granted: 1984-10-09
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Expires: 2001-08-13
Abstract
Abstract A process for producing a substantially isocyanurate-free uretidione dimer of isophorone diisocyanate, which is more than 98% decomposable by heat to isophorone diisocyanate, which comprises dimerizing isophorone diisocyanate, optionally in an inert organic solvent, in the presence of a catalyst of the formula X m P(NR 2 ) 3-m wherein m=0, 1, 2; X=Cl OR of R wherein R is selected from the group consisting of the same or different aklyl radical, aralkyl radical, cycloalkyl radical, substituted cycloalkyl radical and radicals wherein two or more of the aforementioned radicals form a hererocyclic ring together with the nitrogen atom; at temperatures of 0°-80° C., isolating the resulting 1,3-diazacyclobutane-2,4-dione, after 5-70% conversion, without previous inactivation of the catalyst, from the reaction mixture as the residue of a thin film distillation and isolating the catalyst and monomer as the distillate.
Inventors
- 👤 Josef Disteldorf
- 👤 Werner Hubel
- 👤 Elmar Wolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:04
CPC Classifications
C; C07; C07D; C07D229/00; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/77; C08G18/78; C08G18/79; C08G18/798; C08G2150/00; C08G2150/20
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
118 words
A process for producing a substantially isocyanate-free uretidione dimer of isophorone diisocyanate, which is more than 98% decomposable by heat to isophorone diisocyanate, which comprises: dimerizing isophorone diisocyanate in the presence of a catalyst of the formula X.sub.m P(NR.sub.2).sub.3-m wherein m=0, 1, or 2, X=Cl, OR or R, and R is selected from the group consisting of the same or different C 1 -C 8 -alkyl radical, benzyl radical, phenylethyl radical, cyclohexyl radical, and cyclopentyl radical, at temperatures of 0°-80° C., isolating the resulting 1,3-diazacyclobutane-2,4-dione after 5-70% conversion, without previous inactivation of the catalyst, from the reaction mixture as the residue of a thin film distillation and isolating the catalyst and monomer as the distillate of said distillation.
Claim 2
Dependent Claim
118 words
A process for producing a substantially isocyanate-free uretidione dimer of isophorone diisocyanate, which is more than 98% decomposable by heat to isophorone diisocyanate, which comprises: dimerizing isophorone diisocyanate in the presence of a catalyst of the formula X.sub.m P(NR.sub.2).sub.3-m wherein m=0, 1, or 2, X=Cl, OR or R, and R is selected from the group consisting of the same or different C 1 -C 8 -alkyl radical, benzyl radical, phenylethyl radical, cyclohexyl radical, and cyclopentyl radical, at temperatures of 0°-80° C., isolating the resulting 1,3-diazacyclobutane-2,4-dione after 5-70% conversion, without previous inactivation of the catalyst, from the reaction mixture as the residue of a thin film distillation and isolating the catalyst and monomer as the distillate of said distillation.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein said dimerization reaction is carried out at 10°-30° C.
Claim 4
Dependent Claim
16 words
The process of claim 1 wherein said isolation is carried out after 20-50% conversion has occured.
Claim 5
Dependent Claim
22 words
The process of claim 1 wherein said catalyst has the formula P(NR.sub.2).sub.3 and is present in an amount of 0.01-5% by weight.
Claim 6
Dependent Claim
17 words
The process of claim 4 wherein said catalyst is present in an amount of 0.5-2% by weight.
Claim 7
Dependent Claim
14 words
The process of claim 1 or 4 wherein said catalyst has the formula P(N(CH.sub.3).sub.2).sub.3.
Claim 8
Dependent Claim
21 words
The process of claim 1 wherein any unreacted isophorone diisocyanate recovered from the reaction mixture is returned to the reaction mixture.
Claim 9
Dependent Claim
11 words
The process of claim 1 wherein R is methyl or ethyl.
Claim 10
Dependent Claim
23 words
An uretidione dimer of isophorone diisocyanate which is substantially free of isocyanurate and which is more than 98% decomposable by heat to isophoronediisocyanate.
Claim 11
Dependent Claim
23 words
An uretidione dimer of isophorone diisocyanate which is substantially free of isocyanurate and which is more than 98% decomposable by heat to isophoronediisocyanate.
Claim 12
Dependent Claim
13 words
The uretidione dimer of claim 9 which has an NCO content of 16.8-18%.
Claim 13
Dependent Claim
18 words
The uretidione dimer of claim 9 wherein the content of monomeric IPDI is less than 1% by weight.
Claim 14
Dependent Claim
10 words
The uretidione dimer prepared by the process of claim 7.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-09 | 1988-04-09 | 1988-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-09 | 1992-04-09 | 1992-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-09 | 1996-04-09 | 1996-10-09 | $7700.00 | Window Closed / Lapsed |