Claims
- 1. A method for making a fiber or filament of a swellable polymer of high tensile strength, which method consists essentially of reacting a fiber or filament of an untreated copolymer of acrylonitrile containing about 10 to 30 percent by weight of carboxyl groups with a base in the absence of water to convert said carboxyl groups at least partially into a corresponding salt form.
- 2. A swellable fiber or filament made by the method of claim 1.
- 3. A swellable fiber or filament as in claim 1 having a knot strength of at least 8 cN/tex.
- 4. A method as in claim 1 wherein said base is a compound having at least one nitrogen atom.
- 5. A method as in claim 1 wherein said base is reacted in the gaseous state with said carboxyl groups.
- 6. A method as in claim 1 wherein said base is ammonia, hydrazine, or an organic compound vaporizing below 200.degree. C. and selected from the group consisting of amines, heterocyclic nitrogen compounds, and hydrazines.
- 7. A swellable filament or fiber made by the method of claim 1 and exhibiting in the dry state, a tensile strength above 10 cN/tex and a knot strength above 6 cN/tex whereby said filaments or fibers are suitable for processing into waddings, yarns and sheet structures.
- 8. The filament or fiber of claim 1 wherein the knot strength is at least 8 cN/tex.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3034660 |
Sep 1980 |
DEX |
|
Parent Case Info
This is a continuation of application Ser. No. 548,021 filed Nov. 2, 1983 and now abandoned, which in turn is a continuation of Ser. No. 301,411 filed Sept. 11, 1981 and now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4143200 |
Radlmann et al. |
Mar 1979 |
|
4337328 |
Holst |
Jun 1982 |
|
Foreign Referenced Citations (3)
Number |
Date |
Country |
49-007526 |
Jan 1974 |
JPX |
50-075265 |
Jun 1975 |
JPX |
53-123453 |
Oct 1978 |
JPX |