Claims
- 1. A process for preparing a poly(paralphenylene terephthalamide) paper comprising the steps of:
- (a) combining, under agitation to yield a slurry:
- (i) a poly(paraphenylene terephthalamide) fibrous gel composition prepared by a process consisting essentially of placing substantially stoichiometric amounts of terephthaloyl chloride in reactive contact with para-phenylenediamine in a solution of at least one amide solvent in an amount sufficient to yield a final concentration of poly(paraphenylene terephthalamide) in the range from about 3 to about 7 percent by weight of the solvent, at least 1.5 moles of an alkaline earth metal salt per mole of para-phenylenediamine and N-methylpyrrolidine present in the range of from 1.0 to 2.0 moles per mole of para-phenylenediamine;
- (ii) poly(paraphenylene terephthalamide) fiber; and
- (iii) a liquid precipitating medium;
- (b) pouring the slurry onto a screen to yield a sheet;
- (c) washing the sheet;
- (d) pressing the sheet; and
- (e) drying the sheet.
- 2. The process of claim 1 wherein the fibrous gel is diluted with an amide solvent before combining with the poly(paraphenylene terephthalamide) fiber and the liquid precipitating medium.
- 3. The process of claim 2 wherein the amide solvent is N-methylpyrrolidone.
- 4. A process for preparing a poly(paraphenylene terephthalamide) paper comprising the steps of:
- (a) combining, under agitation to yield a slurry:
- (i) a poly(paraphenylene terephthalamide) fibrous gel composition prepared by a process consisting essentially of placing substantially stoichiometric amounts of terephthaloyl chloride in reactive contact with para-phenylene diamine in a solution of at least one amide solvent in an amount sufficient to yield a final concentration of poly(paraphenylene terephthalamide) in the range from about 3 to about 7 percent by weight of the solvent, at least 1.5 moles of an alkaline earth metal salt per mole of para-phenylenediamine and N-methylpyrrolidine hydrochloride present in the range of from 1.5 to 4.0 moles per mole of para-phenylenediamine;
- (ii) poly(paraphenylene terephthalamide) fiber; and
- (iii) a liquid precipitating medium;
- (b) pouring the slurry onto a screen to yield a sheet;
- (c) washing the sheet;
- (d) pressing the sheet; and
- (e) drying the sheet.
- 5. The process of claim 4 wherein the fibrous gel is diluted with an amide solvent before combining with the poly(paraphenylene terephthalamide) fiber and the liquid precipitating medium.
- 6. The process of claim 5 wherein the amide solvent is methylpyrrolidone.
Parent Case Info
This is a division of application Ser. No. 07/332,792, filed Apr. 3, 1989, now U.S. Pat. No. 4,959,453.
US Referenced Citations (8)
Non-Patent Literature Citations (2)
Entry |
U.S. Ser. No. 07/213,741, filed Jun. 30, 1988. |
Japanese Patent Application 52-124099, published Oct. 18, 1977. |
Divisions (1)
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Number |
Date |
Country |
Parent |
332792 |
Apr 1989 |
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