Claims
- 1. In an isocyanate polyaddition process for the production of polyurethane resins, the improvement comprising reacting
- a. polyisocyanates having biuret groups produced by reacting
- i. excess quantities of organic polyisocyanates of the formula
- Q(NCO).sub.2
- wherein Q represents an aliphatic hydrocarbon group having from 4 to 12 carbon atoms or a cycloaliphatic hydrocarbon group having from 4 to 15 carbon atoms with
- ii. a mixture of water and diprimary diamines of the formula
- R'(NH.sub.2).sub.2
- wherein R' represents an aliphatic hydrocarbon group having 2 to 12 carbon atoms, a cycloaliphatic hydrocarbon group having 4 to 17 carbon atoms, or an araliphatic hydrocarbon group having 8 to 10 carbon atoms, with
- b. polyhydroxyl compounds.
- 2. The process of claim 1, wherein the diprimary diamines are selected from the group consisting of tetramethylene diamine, 1,2-bis-(aminomethyl)-cyclobutane and hexamethylenediamine and the organic polyisocyanate is hexamethylene diisocyanate.
- 3. Process according to claim 1, characterized in that the organic polyisocyanates are reacted with quantities of the mixture of water and amine such that the molar ratio of (NCO groups of the diisocyanate): (H.sub.2 O+primary amino groups of the amine) present in the reaction mixture is between about 3:1 and 100:1.
- 4. Process according to claim 1, characterized in that the water and amine are used in quantities corresponding to an equivalent ratio of water:primary amino groups of between about 5:1 and 1:5.
- 5. Process according to claim 1, characterized in that the polyisocyanates to be used in the process are pretreated before use by heating for about 6 to 10 hours at about 120.degree. to 195.degree. C. and are then distilled.
- 6. Process according to claim 1, characterized in that the mixture of water and amine is reacted in vapor form with the polyisocyanates which have been heated to a temperature of from about 60.degree. to 200.degree. C.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2619548 |
May 1976 |
DEX |
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Parent Case Info
This is a division of application Ser. No. 789,902 filed Apr. 22, 1977 now U.S. Pat. No. 4,127,599.
US Referenced Citations (4)
Number |
Name |
Date |
Kind |
3862973 |
Dietrich et al. |
Jan 1975 |
|
3903126 |
Woerner et al. |
Sep 1975 |
|
3903127 |
Wagner et al. |
Sep 1975 |
|
4127599 |
Mohring et al. |
Nov 1978 |
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Divisions (1)
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Number |
Date |
Country |
Parent |
789902 |
Apr 1977 |
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