← Back to Patent Explorer
US4014935A Expired / Lapsed US ⏱️ 0.0 years remaining

Carbodiimides

Assignee: Imperial Chemical Industries Ltd
•
Filing: 1976-03-25
•
Granted: 1977-03-29
•
Expires: 1996-03-25
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A process for the conversion of isocyanate groups in a refined organic isocyanate into carbodiimide groups which comprises heating said organic isocyanate with a catalyst of the formula: <IMAGE> or <IMAGE> or the 2,3 or 3,4-mono-unsaturated analogues thereof, wherein R is an optionally substituted hydrocarbyl group, R1 to R8 which may be the same or different are hydrogen, chlorine or lower alkyl, X and Y may be chlorine or bromine or X and Y taken together may represent the divalent atoms =O or =S or the divalent radial =N aryl, followed by deactivation of the catalyst by adsorption on a substrate or by addition of one or more of the halides of hydrogen, phosphorus or tin or an oxyhalide of phosphorus or sulphur. When only partial conversion takes place the carbodiimides react with further isocyanate groups to give uretonimines. The products are useful for the manufacture of polymers especially microcellular polyurethanes.

Inventors

  • 👤 Arthur Ibbotson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 08:22
CPC Classifications
C; C07; C07D; C07D229/00; C07C; C07C267/00; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/74; C08G18/76; C08G18/7657; C08G18/7664; C08G18/7671; C08G18/77; C08G18/78; C08G18/79; C08G18/797; Y; Y10; Y10S; Y10S521/00; Y10S521/901

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 146 words
A process for the conversion of from 3% to 35% of the isocyanate groups in a refined aromatic polyisocyanate having two or more isocyanate groups, into carbodiimide groups which comprises heating said isocyanate with a catalyst of the formula: ##STR12## wherein R is phenyl, benzyl or ethyl, R 1 , R 2 , R 5 , R 6 , R 7 and R 8 are hydrogen, R 4 is methyl, X and Y may be chlorine or bromine or X and Y taken together may represent the divalent atoms =O or =S or the divalent radical =N aryl, m and n represent 0 or 1 and are the same in any one compound, followed by deactivation of the catalyst by adsorption on a substrate or by addition of one or more of the halides of hydrogen, phosphorus or tin or an oxyhalide of phosphorus or sulphur.
Claim 2
Dependent Claim 146 words
A process for the conversion of from 3% to 35% of the isocyanate groups in a refined aromatic polyisocyanate having two or more isocyanate groups, into carbodiimide groups which comprises heating said isocyanate with a catalyst of the formula: ##STR12## wherein R is phenyl, benzyl or ethyl, R 1 , R 2 , R 5 , R 6 , R 7 and R 8 are hydrogen, R 4 is methyl, X and Y may be chlorine or bromine or X and Y taken together may represent the divalent atoms =O or =S or the divalent radical =N aryl, m and n represent 0 or 1 and are the same in any one compound, followed by deactivation of the catalyst by adsorption on a substrate or by addition of one or more of the halides of hydrogen, phosphorus or tin or an oxyhalide of phosphorus or sulphur.
Claim 3
Dependent Claim 34 words
A process as claimed in claim 1 wherein the catalyst is deactivated by the addition of one or more of the halides of hydrogen, phosphorus or tin or an oxyhalide of phosphorus or sulphur.
Claim 4
Dependent Claim 23 words
A process as claimed in claim 1 wherein the catalyst is deactivated by adsorption on a substrate followed by removal of the substrate.
Claim 5
Dependent Claim 18 words
A process as claimed in claim 1 wherein X and Y taken together represent a divalent oxygen atom.
Claim 6
Dependent Claim 14 words
A process as claimed in claim 4 wherein the catalyst is 1-phenyl-3-methyl phospholene oxide.
Claim 7
Dependent Claim 28 words
A process as claimed in claim 1 wherein the catalyst is used in an amount of from 1 ppm to 100 ppm on the weight of the isocyanate.
Claim 8
Dependent Claim 27 words
A process as claimed in claim 6 wherein the catalyst is used in an amount of from 1 to 25 ppm on the weight of the isocyanate.
Claim 9
Dependent Claim 18 words
A process as claimed in claim 7 wherein the amount of catalyst is from 1 to 10 ppm.
Claim 10
Dependent Claim 14 words
A process as claimed in claim 1 wherein the isocyanate is a diphenylmethane diisocyanate.
Claim 11
Dependent Claim 32 words
A process as claimed in claim 1 wherein at least a proportion of the carbodiimide groups react with further isocyanate groups in the refined organic isocyanate on standing to form uretonimine groups.
Claim 12
Dependent Claim 19 words
A process as claimed in claim 1 wherein the conversion is carried out at a temperature below 150° C.
Claim 13
Dependent Claim 17 words
A process as claimed in claim 11 wherein the temperature is from 80° C to 140° C.
Claim 14
Dependent Claim 33 words
A process as claimed in claim 2 wherein deactivation of the catalyst is carried out by the addition of from one to thirty moles of a deactivating agent as claimed in claim 2.
Claim 15
Dependent Claim 14 words
A process as claimed in claim 2 wherein the deactivating agent is thionyl chloride.
Claim 16
Dependent Claim 19 words
A process as claimed in claim 3 wherein the catalyst is deactivated by absorption on a siliceous earth substrate.
Claim 17
Dependent Claim 44 words
A process as claimed in claim 1 wherein conversion of isocyanate groups is carried out beyond the desired level of conversion and the product blended with a further amount of refined isocyanate to give a product having the desired number of unconverted isocyanate groups.
Claim 18
Dependent Claim 16 words
Process as claimed in claim 1 wherein an acid acceptor is incorporated in the reaction mixture.
Claim 19
Dependent Claim 13 words
Process as claimed in claim 17 wherein the acid acceptor is a 1,2-epoxide.
Claim 20
Dependent Claim 29 words
Process as claimed in claim 17 wherein the acid acceptor is used in an amount of at least one equivalent for each gram molecule of acidity in the isocyanate.

References Cited (Backward Citations)

US2840589A Cited
US3056835A Cited
GB1356851A Cited
US3907780A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-03-28 1980-09-27 1981-03-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-03-28 1984-09-27 1985-03-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-03-28 1988-09-27 1989-03-29 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag