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Preparation of carbodiimide in presence of phospholene catalysts

Assignee: Pharmacia and Upjohn Co
•
Filing: 1977-10-31
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Granted: 1978-08-08
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Expires: 1997-10-31
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Abstract

Abstract Modified polystyrenes are described which are catalysts for the conversion of organic isocyanates to the corresponding carbodiimides. The modified polystyrenes are characterized by the presence of recurring units of the formula: ##STR1## WHEREIN THE BROKEN LINES IN THE PHOSPHOLENE NUCLEUS INDICATE A DOUBLE BOND LOCATED BETWEEN THE CARBON ATOM AT POSITION 3 AND ONE OF THE CARBON ATOMS AT POSITIONS 2 AND 4, THE H atom is attached to whichever carbon atom at positions 2 and 4 is not part of said double bond, R is halogen, alkoxy (C 1-6 ), phenoxy, hydrocarbyl (C 1-18 ), halohydrocarbyl (C 1-18 ), m = 0-3; n = 0, 1; R 1 is hydrogen or methyl; and R 2 is hydrocarbyl free from substituents reactive with isocyanate.

Inventors

  • 👤 Curtis P. Smith

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 22:30
CPC Classifications
C; C08; C08F; C08F8/00; C08F8/40

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 176 words
In a process for the preparation of a carbodiimide by heating the appropriate organic isocyanate in the presence of a catalyst, the improvement which comprises employing as said catalyst a polymer characterized by the presence therein of a recurring unit having the formula: ##STR10## wherein the broken lines in the phospholene nucleus indicate a double bond located between the carbon atom at position 3 and one of the carbon atoms at positions 2 and 4, the H atom is attached to whichever carbon atom at positions 2 and 4 is not part of said double bond, R is a substituent selected from the class consisting of halogen, alkoxy from 1 to 6 carbon atoms, inclusive, phenoxy, hydrocarbyl from 1 to 18 carbon atoms, inclusive, and halohydrocarbyl from 1 to 18 carbon atoms, inclusive, m is a whole number from 0 to 3, n is 0 or 1 and RS 1 is selected from the class consisting of hydrogen and methyl and R 2 represents hydrocarbyl said hydrocarbyl being free of substituents which are reactive with isocyanate.
Claim 2
Dependent Claim 176 words
In a process for the preparation of a carbodiimide by heating the appropriate organic isocyanate in the presence of a catalyst, the improvement which comprises employing as said catalyst a polymer characterized by the presence therein of a recurring unit having the formula: ##STR10## wherein the broken lines in the phospholene nucleus indicate a double bond located between the carbon atom at position 3 and one of the carbon atoms at positions 2 and 4, the H atom is attached to whichever carbon atom at positions 2 and 4 is not part of said double bond, R is a substituent selected from the class consisting of halogen, alkoxy from 1 to 6 carbon atoms, inclusive, phenoxy, hydrocarbyl from 1 to 18 carbon atoms, inclusive, and halohydrocarbyl from 1 to 18 carbon atoms, inclusive, m is a whole number from 0 to 3, n is 0 or 1 and RS 1 is selected from the class consisting of hydrogen and methyl and R 2 represents hydrocarbyl said hydrocarbyl being free of substituents which are reactive with isocyanate.
Claim 3
Dependent Claim 26 words
A process according to claim 1 wherein said catalyst is a polymer having a recurring unit of the formula: ##STR11## wherein m is 0 or 1.

References Cited (Backward Citations)

US3767708A Cited
US3855186A Cited
US3855352A Cited
US4067820A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-08-07 1982-02-06 1982-08-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-08-07 1986-02-06 1986-08-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-08-07 1990-02-06 1990-08-08 $7700.00 Window Closed / Lapsed

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