Claims
- 1. An improved single phase liquid spin solution for flash-spinning plexifilamentary film-fibril strands consisting essentially of 8 to 35 weight percent of a fiber-forming polyolefin and 65 to 92 weight percent of a hydrocarbon/co-solvent spin liquid, the spin liquid consisting essentially of less than 90 weight percent of a hydrocarbon spin liquid selected from the group consisting of isobutane, butane, cyclobutane, 2-methyl butane, 2,2-dimethyl propane, pentane, methyl cyclobutane, cyclopentane, 2,2-dimethylbutane, 2,3-dimethylbutane, 2-methylpentane, 3-methylpentane, hexane, methyl cyclopentane, cyclohexane, 2-methyl hexane, 3-methyl hexane, heptane and mixtures thereof and greater than 10 weight percent of a co-solvent spin liquid having lower solvent strength than said hydrocarbon spin liquid and having an atmospheric boiling point of less than 100° C. and selected from the group consisting of inert gases, hydrofluorocarbons, hydrochlorofluorocarbons, perfluorinated hydrocarbons, polar solvents and mixtures thereof.
- 2. The spin solution according to claim 1 wherein the fiber-forming polyolefin is selected from the group consisting of polyethylene and polypropylene.
- 3. The spin solution according to claim 1 wherein the co-solvent spin liquid is a polar solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, 2-butanone, and tertiary-butyl alcohol, and mixtures thereof.
- 4. The spin solution according to claim 1 wherein the cloud point pressure of the spin solution is greater than 900 psig at temperatures of 300° C. or less.
- 5. The spin solution according to claim 1 wherein the cloud point pressure of the spin solution is greater than 1500 psig at temperatures of 300° C. or less.
- 6. The spin solution according to claim 1 wherein said co-solvent is a perfluorinated hydrocarbon.
- 7. The spin solution according to claim 1 wherein said co-solvent is a hydrofluorocarbon.
- 8. The spin solution according to claim 1 wherein said co-solvent is a hydrochlorofluorocarbon.
Parent Case Info
This is a continuation of application Ser. No. 08/096,568 filed Jul. 30, 1993, now abandoned, which was a continuation of application Ser. No. 07/859,562 filed Mar. 26, 1992, now abandoned, which is in turn a divisional of application Ser. No. 07/660,768, filed Feb. 22, 1991, now U.S. Pat. No. 5,147,586.
US Referenced Citations (8)
Foreign Referenced Citations (3)
Number |
Date |
Country |
0357364 |
Mar 1990 |
EP |
891945 |
Mar 1962 |
GB |
891943 |
Mar 1962 |
GB |
Non-Patent Literature Citations (1)
Entry |
P.S. Zurer, “Search Intensifies for Alternatives to Ozone Depleting Halocarbons,” Chem & Eng. News, pp. 17-20 (Feb. 8, 1988). |
Continuations (2)
|
Number |
Date |
Country |
Parent |
08/096568 |
Jul 1993 |
US |
Child |
08/279317 |
|
US |
Parent |
07/859562 |
Mar 1992 |
US |
Child |
08/096568 |
|
US |