Claims
- 1. A process for producing an aromatic imide polymer hollow filament having excellent heat resistance, chemical resistance, mechanical strength, and which exhibits a gas selective permeability ratio of hydrogen gas permeating rate to carbon monoxide gas permeating rate of at least about 40, and hydrogen gas permeating rate of at least about 3.times.10.sup.-5 cm.sup.3 /cm.sup.2.sec.cmHg, said process comprising the steps of:
- (1) dissolving an aromatic imide copolymer comprising:
- (A) 20 to 80 molar % of recurring units of the Formula (I): ##STR17## (B) 10 35 molar % of recurring units of the Formula (II): ##STR18## (C) 5 to 55 molar % of recurring units of the Formula (III): ##STR19## wherein R represents a divalent radical selected from those of the Formulae (IV) and V): ##STR20## R.sup.1 and R.sup.2, respectively, represent, independently from each other, a member selected from the group consisting of a hydrogen atom, alkoxyl radicals having 1 to 3 carbon atoms and alkyl radicals having 1 to 3 carbon atoms, in a solvent consisting essentially of at least one phenolic compound to provide a stable spinning dope solution and wherein the aromatic imide copolymer in the dope solution is in a concentration of from 10% to 20% by weight;
- (2) extruding the dope solution while said solution is at a temperature of from 0.degree. to 150.degree. C., and wherein the dope solution has a rotation viscosity of at least 500 centipoises at a temperature of 20.degree. C. to 120.degree. C., through a spinneret having at least one hollow filament spinning orifice, to provide at least one hollow filamentary stream of the dope solution; and
- (3 ) introducing the dope solution hollow filamentary stream into a coagulating bath wherein said coagulating bath has a temperature of -10.degree. C. to 60.degree. C., and wherein said coagulating bath is comprised of at least one polar solvent which is compatible with the phenolic compound, but substantially not capable of dissolving the aromatic imide copolymer, to solidify the hollow filamentary stream into a hollow filament.
- 2. The process as claimed in claim 1, wherein the aromatic imide copolymer has a degree of imidization of 90% or more.
- 3. The process as claimed in claim 1, wherein the aromatic imide copolymer has a logarithmic viscosity of from 0.3 to 7.0, determined at a concentration of 0.5 g per 100 ml of a solvent consisting of a mixture of 4 parts by volume of p-chlorophenol with 1 part by volume of o-chlorophenol at a temperature of 30.degree. C.
- 4. The process as claimed in claim 1, wherein the aromatic imide copolymer in the dope solution is in a concentration of from 12% to 20% by weight.
- 5. The process as claimed in claim 1, wherein the solvent for the dope solution consists essentially of at least one phenolic compound selected from the group consisting of phenol, o-, m-, and p-cresols, 3,5-xylenol, and halogenated phenol compounds of the formula (VIII): ##STR21## wherein X represents a halogen atom and R.sup.3 represents a member selected from the group consisting of a hydrogen atom and alkyl radicals having 1 to 3 carbon atoms, which halogenated phenol compound has a melting point of 100.degree. C. or less and a boiling point of 300.degree. C. or less under an ambient atmospheric pressure.
- 6. The process as claimed in claim 1, wherein the dope solution to be extruded has a temperature of from 20.degree. C. to 120.degree. C.
- 7. The process as claimed in claim 1, wherein the dope solution has a rotation viscosity of from 10 to 100,000 poises at a temperature of 20.degree. C. to 120.degree. C.
- 8. The process as claimed in claim 1, wherein the polar solvent is selected from the group consisting of mixtures of water with a lower aliphatic alcohol having 1 to 5 carbon atoms.
- 9. The process as claimed in claim 1, wherein the divalent radical represented by R in the formula (III) is of the formula (V).
- 10. The process as claimed in claim 1, wherein the recurring units of the formula (II) are of the formula: ##STR22##
Priority Claims (1)
Number |
Date |
Country |
Kind |
59-125340 |
Jun 1984 |
JPX |
|
Parent Case Info
This application is a continuation, of application Ser. No. 745,144, filed June 14, 1985, abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4378324 |
Makino et al. |
Mar 1983 |
|
4378400 |
Makino et al. |
Mar 1983 |
|
4460526 |
Makino et al. |
Jul 1984 |
|
Continuations (1)
|
Number |
Date |
Country |
Parent |
745144 |
Jun 1985 |
|