Claims
- 1. A flexible water swellable crosslinked polyacrylate film produced by the method which comprises
- A. applying a coating on an impervious substrate wherein the coating comprises a crosslinkable aqueous solution which is prepared by forming a polyacrylate solution having about 30 to about 70 weight percent alkali metal carboxylates by dissolving in an aqueous alkali metal hydroxide solution a polyacrylate comprising
- 1. about 30 to about 92 percent by weight of an alkyl acrylate wherein the alkyl group has 1-10 carbon atoms, an alkyl methacrylate wherein the alkyl group has 4-10 carbon atoms, or mixtures thereof,
- 2. about 8 to about 50 percent by weight of an olefinically unsaturated carboxylic acid, and
- 3. about 0 to about 15 percent by weight of an omega hydroxy-alkyl acrylate having 1-4 carbon atoms in the hydroxy alkyl group,
- heating the solution until saponification is complete, and adding to said solution about 0.1 to about 10 weight percent, based on the dissolved polymer of a water soluble crosslinking agent which is reactive with carboxylate salt groups
- B. heating said coated substrate to a temperature greater than about 30.degree. C to crosslink said polyacrylate, and
- C. separating said crosslinked film from said substrate.
CROSS REFERENCE TO RELATED APPLICATION
This is a division of application Ser. No. 450,650, filed Mar. 13, 1974, now U.S. Pat. No. 3,926,891.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
3224986 |
Butler et al. |
Dec 1965 |
|
3808305 |
Gregor |
Apr 1974 |
|
Divisions (1)
|
Number |
Date |
Country |
Parent |
450650 |
Mar 1974 |
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