Claims
- 1. A process for preparing a composite semipermeable membrane which comprises coating or impregnating a porous substrate with an aqueous solution containing polyvinyl alcohol and an amino compound having at least two secondary amino groups, thereafter contacting said porous substrate with a polyfunctional crosslinking reagent capable of reacting with secondary amino groups and hydroxyl groups to polymerize the polyvinyl alcohol and the amino compound by crosslinking, and then heating the product at a temperature of from 80.degree. to 180.degree. C.
- 2. A process for preparing a composite semipermeable membrane according to claim 1, wherein said aqueous solution of the mixture of polyvinyl alcohol and the amino compound contains from 10 to 500 parts by weight of the amino compound per 100 parts by weight of the polyvinyl alcohol.
- 3. A process for preparing a composite semipermeable membrane according to claim 1 wherein a weight loss of said amino compound is at least 50 wt% when heated to a temperature of 130.degree. C. for 30 minutes.
- 4. A process for preparing a composite semipermeable membrane according to claim 3 wherein said amino compound is represented by formula (I)
- R.sup.1 --NH--A--NH--R.sup.2 (I)
- wherein A represents an alkylene group having from 2 to 8 carbon atoms, a divalent alicyclic group, a divalent aromatic group, or a divalent heteroaromatic group, and R.sup.1 and R.sup.2 each represents an alkyl group having from 1 to 3 carbon atoms.
- 5. A process for preparing a composite semipermeable membrane according to claim 3 wherein said amino compound is represented by formula (II) ##STR7## wherein R.sup.3 represents an alkylene group having from 0 to 4 carbon atoms, R.sup.4 and R.sup.5 each represents an alkyl group having from 1 to 3 carbon atoms, and i and j each represents an integer of from 0 to 4.
- 6. A process for preparing a composite semipermeable membrane according to claim 3 wherein said amino compound is represented by formula (III) ##STR8## wherein R.sup.6 and R.sup.7 each represents an alkyl group having from 1 to 3 carbon atoms, k and l each represents an integer of 0 to 4, and m represents an integer of 0 to 4.
- 7. A process for preparing a composite semipermeable membrane according to claim 3, wherein said amino compound is represented by formula (IV) ##STR9## wherein R.sup.8 represents an alkyl group having from 1 to 3 carbon atoms, n represents 1 or 2, and p represents an integer of 0 to 4.
- 8. A process for preparing a composite semipermeable membrane according to claim 1, 2, 3, 4, 5, 6, or 7, wherein said polyfunctional crosslinking reagent has 2 or more functional groups selected from acid halide groups, N-haloformyl groups, haloformate groups, halogen sulfonyl groups, and acid anhydride groups.
- 9. A process for preparing a composite semipermeable membrane according to claim 1, 2, 3, 4, 5, 6, or 7, which comprises coating or impregnating a porous substrate with the aqueous solution of the mixture of polyvinyl alcohol and the amino compound, and thereafter contacting the porous substrate with a crosslinking reagent solution prepared by dissolving a polyfunctional crosslinking reagent in an organic solvent which is substantially immiscible with water.
- 10. A process for preparing a composite semipermeable membrane according to claim 9, wherein said solvent for the crosslinking reagent solution comprises aliphatic or alicyclic hydrocarbons having from 5 to 8 carbon atoms.
- 11. A process for preparing a composite semipermeable membrane according to claim 1, 2, 3, 4, 5, 6, or 7, which comprises coating or impregnating a porous substrate with the aqueous solution of the mixture of polyvinyl alcohol and the amino compound, and thereafter contacting said porous substrate with a vapor of the polyfunctional crosslinking reagent.
- 12. A process for preparing a composite semipermeable membrane according to claim 11 wherein P log T is at least 0.1, wherein P (mm Hg) is the vapor pressure of the polyfunctional crosslinking reagent and T is the contact time (seconds).
- 13. A process for preparing a composite semipermeable membrane according to claim 1, 2, 3, 4, 5, 6, 7, wherein said porous substrate comprises polystyrene, polyacrylonitrile, cellulose ester, polypropylene, or polyvinyl chloride.
- 14. A process for preparing a composite semipermeable membrane according to claim 1, wherein said aqueous solution of the mixture of polyvinyl alcohol and the amino compound contains from 20 to 300 parts by weight of the amino compound per one hundred weight of the polyvinyl alcohol.
- 15. A process for preparing a composite semipermeable membrane according to claim 1, wherein the heating temperature is from 100.degree. to 150.degree. C.
- 16. A process for preparing a composite semipermeable membrane according to claim 1, wherein the heating time is from 1 to 60 minutes.
- 17. A process for preparing a composite semipermeable membrane according to claim 15, wherein the heating time is from 1 to 60 minutes.
- 18. A process for preparing a composite semipermeable membrane according to claim 12, wherein P log T is at least 0.3.
Priority Claims (1)
Number |
Date |
Country |
Kind |
55-103291 |
Jul 1980 |
JPX |
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Parent Case Info
This is a division of application Ser. No. 287,653, filed July 18, 1981, now U.S. Pat. No. 4,619,767.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4242208 |
Kawaguchi et al. |
Dec 1980 |
|
4337154 |
Fukucth et al. |
Jun 1982 |
|
4353802 |
Hara et al. |
Oct 1982 |
|
Divisions (1)
|
Number |
Date |
Country |
Parent |
287653 |
Jul 1981 |
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