Method of using mixed aliphatic/aromatic polycarbodiimides

• US 4,587,301 A
• Filed: 11/29/1984
• Issued: 05/06/1986
• Est. Priority Date: 02/24/1983
• Status: Expired due to Fees

• Current Assignee: Union Carbide Corporation (Dow, Inc.)
• Original Assignee: Union Carbide Corporation (Dow, Inc.)
• Inventors: Watson, Stuart L. Jr., Humphreys, Gordon R.
• Primary Examiner(s): Bleutge, John C.
• Assistant Examiner(s): Carrillo, A. L.
• Application Number:
  US06/676,084
• Time in Patent Office: 523 Days
• Field of Search: 525/907, 525/123
• US Class Current: 525/123
• CPC Class Codes: C08G 18/025 the polymeric products containing carbodiimide groups
• CPC Class Codes: C08K 5/29 Compounds containing one or more carbon-to-nitrogen double bonds
• CPC Class Codes: Y10S 525/907 Polycarbodiimide

Abstract

Mixed aliphatic/aromatic polycarbodiimides can be prepared by first heating aliphatic mono- and diisocyanates with a phospholene oxide catalyst and then feeding the aromatic mono and/or diisocyanates in an inert solvent to the reaction mixture. These polycarbodiimides find use in a method for cross-linking carboxylated latexes.

Claims

1. A method of preparing a cross-linkable composition comprising admixing:

(a) a carboxylated latex,

(b) a cross-linking catalyst, and

(c) a mixed aliphatic and aromatic polycarbodiimide prepared by a process comprising the following steps seriatim;

(A) charging a mixture of cycloaliphatic or saturated aliphatic mono- and diisocyanates to a reactor with agitation under an inert atmosphere;

(B) heating the resultant mixture to about 120°

to about 160°

C.;

(C) adding a catalytic amount of a phospholene oxide catalyst to the reactor;

(D) feeding a mixture of a non-reactive solvent and aromatic mono- and/or diisocyanate to the reactor; and

(E) maintaining agitation at about 120°

to about 160°

C. until all of the isocyanate functionality is converted to carbodiimide functionality, with the provisos that;

(a) said cycloaliphatic moieties contain 6 to about 10 carbons;

(b) said saturated aliphatic moieties contain from about 4 to about 12 carbons;

(c) said aromatic moieties contain from 6 to about 16 carbons;

(d) the molar ratio of all of the mono-to-diisocyanates ranges from about 2;

1 to about 2;

10; and

(e) the molar ratio of cycloaliphatic and/or saturated aliphatic isocyanate groups to aromatic isocyanate groups ranges from about 0.5;

1 to about 2;

1.

2. A method of claim 1 wherein the molar ratio of cycloaliphatic and/or saturated aliphatic mono- and diisocyanates to aromatic mono- and diisocyanates ranges from about 0.75:

1 to about 1.25;

1.

3. A method of claim 2 wherein the aliphatic monoisocyanate is butyl isocyanate and the cycloaliphatic diisocyanate is isophorone diisocyanate.

4. A method of claim 2 wherein the aromatic diisocyanate is toluene diisocyanate.

5. A method of claim 1 using phenyl isocyanate, isophorone diisocyanate and toluene diisocyanate.

6. A method of claim 1 carried out in a non-reactive organic solvent.

7. A method of claim 6 wherein the solvent is a glycol diester.

8. A method of claim 6 wherein the solvent is an aliphatic ester.

9. A method of claim 1 wherein the phospholene oxide catalyst is 3-methyl-1-phenyl-2-phospholene-1-oxide.

10. A method of claim 1 wherein the cross-linking catalyst is an amine.