Claims
- 1. A method of preparing a substantially dry water swellable particulate polyelectrolyte which comprises the steps of
- A. applying a coating on an impervious substrate wherein the coating comprises
- 1. a solution of a carboxylic synthetic polyelectrolyte wherein the solution comprises water, lower alcohols, or mixtures thereof and about 5 to about 60% by weight of a carboxylic polyelectrolyte, and
- 2.
- 2. at least about 0.1% by weight based on the polyelectrolyte of a crosslinking agent reactive with carboxylate groups,
- B. heating said coated substrate to a temperature greater than about 30.degree.C. to crosslink said polyelectrolyte to form a film,
- C. separating said crosslinked polyelectrolyte film from said substrate, and
- D. disintegrating said film to form flakes, strips, or powders thereof. 2. The method as set forth in claim 1 wherein the crosslinking agent reactive with carboxylate groups is selected from polyhaloalkanoles, sulfonium zwitterions, haloepoxyalkanes, polyglycidyl ethers, and mixtures thereof.
- 3. The method as set forth in claim 2 wherein the crosslinking agent is a polyglycidyl ether.
- 4. The method as set forth in claim 3 wherein the crosslinking agent is an alkylene glycol diglycidyl ether.
- 5. The method as set forth in claim 3 wherein the crosslinking agent is glycerine-1,3-diglycidyl ether.
- 6. The method as set forth in claim 3 wherein the crosslinking agent is a polypropylene glycol diglycidyl ether having an epoxy equivalent weight range from about 175 to about 380.
- 7. The method as set forth in claim 3 wherein the crosslinking agent is a bisphenol A-epichlorohydrin epoxy resin having an epoxy equivalent weight range from about 182 to about 975.
- 8. The water swellable particulate polyelectrolyte, in the form of flakes or strips, produced by the method of claim 1.
- 9. The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 2.
- 10. The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 3.
- 11. The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 4.
- 12. The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 5.
- 13. The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 6.
- 14. The water swellable polyelectrolyte in the form of flakes or strips produced by the method of claim 7.
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of Ser. No. 468,794 filed May 9, 1974 which is a continution-in-part of Ser. No. 371,909 filed June 20, 1973, which is now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
3669103 |
Harper et al. |
Jun 1972 |
|
3810468 |
Harper et al. |
May 1974 |
|
Divisions (1)
|
Number |
Date |
Country |
Parent |
468794 |
May 1974 |
|
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
371909 |
Jun 1973 |
|