US 5,246,647 A · Process of making microporous hollow fiber or film membrane of poly(phenylene sulfide) (PPS)

Abstract

The present invention relates to a process for preparing a microporous permselective membrane from a poly(phenylene sulfide) (PPS) polymer, an organic compound which substantially solubilizes the PPS below its melting point to form a homogenous mixture, heating the resulting mixture, extruding or casting the mixture into a membrane (fiber or film), quenching or coagulating the membrane, and leaching the membrane, while optionally drawing the membrane before, during, after leaching, or a combination thereof. In one embodiment, the solvent optionally includes an organic non-solvent to assist in obtaining the desired microporsity. The permselective polymers are useful to separate gaseous or liquid components from a mixture of components.

Claims18

Dependent claims

A process for preparing a permselective microporous membrane comprising poly(phenylene sulfide), which process comprises the steps of:

(a) forming a mixture comprising:
(i) poly(phenylene sulfide)
(ii) at least one solvent for the polyphenylene sulfide;
(b) heating the mixture to a temperature under conditions such that a homogeneous fluid is formed which possesses sufficient viscosity to be formed into a membrane;
(c) extruding or casting the homogeneous fluid into a membrane form;
(d) quenching or coagulating the membrane by passing the membrane through one or more zones under physical conditions such that the membrane solidifies;
and
(e) simultaneously or consecutively leaching the membrane by passing the membrane through one or more zones under conditions such that at least a substantial portion of the solvent for the polyphenylene sulfide is removed from the membrane;
wherein the permselective membrane so formed possesses a microporous structure.

6 more elements

A process for preparing a permselective microporous membrane comprising poly(phenylene sulfide), which process comprises the steps of:

(a) forming a mixture comprising:
(i) (polyphenylene sulfide)
(ii) at least one solvent for the polyphenylene sulfide;
(iii) at least one non-solvent for the polyphenylene sulfide;
(b) heating the mixture to a temperature under conditions such that a homogeneous fluid is formed which possesses sufficient viscosity to be formed into a membrane;
(c) extruding or casting the homogeneous fluid into a membrane;
(d) quenching or coagulating the membrane by passing the membrane through one or more zones under physical conditions such that the membrane solidifies;
and
(e) simultaneously or consecutively leaching the membrane by passing the membrane through one or more zones under conditions such that at least a substantial portion of the solvent and non-solvent for the polyphenylene sulfide is removed from the membrane;
wherein the semi-permeable membrane so formed possesses a microporous structure.

7 more elements

Dependencies are inferred from the claim text.

Process of making microporous hollow fiber or film membrane of poly(phenylene sulfide) (PPS)

Life of this patent

Process of making microporous hollow fiber or film membrane of poly(phenylene sulfide) (PPS)

Life of this patent

Abstract

Claims18