Hollow fiber membrane and preparation method thereof

Abstract

The invention discloses a hollow fiber membrane and a preparation method of the hollow fiber membrane. The hollow fiber membrane is characterized in that a mass percent formula of a membrane forming system comprises the following components in percentage by weight (the sum of the components is 100%): 12-30% of a polymer, 70-88% of an organic solvent and 0-10% of an additive, wherein the polymer is a general membrane forming polymer or a modified product; the organic solvent is a good solvent of the polymer and can be mutually dissolved with water; the additive is a substance capable of reacting with water or a water solution to generate gas. The preparation method is a simplified solution spinning method comprising the steps of: firstly preparing the polymer membrane forming system according to the formula, putting the polymer membrane forming system into an injection syringe or other conveniently-extruded containers, extruding polymer membrane forming liquid from a syringe needle or other pipelines under the pushing action of an injection pump or the other containers, soaking the extruded polymer membrane forming liquid into pure water or a water solution which can be an acid water solution or an alkali water solution according to different additives, solidifying and forming the membrane forming system by virtue of the water solution, meanwhile, reacting the additive with water, forming a cavity of the hollow fiber membrane due to the expansion of the generated gas, and finally obtaining the hollow fiber membrane.

Description

technical field [0001] The invention relates to a hollow fiber membrane and a preparation method thereof, belonging to the technical field of membranes. Background technique [0002] The hollow fiber membrane is like a fiber-like, self-supporting membrane. It is a kind of asymmetric membrane, and its dense layer can be located on the outer surface of the fiber (such as reverse osmosis membrane) or on the inner surface of the fiber (such as microfiltration membrane, nanofiltration membrane and ultrafiltration membrane). For gas separation membranes, the dense layer may be located on the inner or outer surface. The separation principle of the hollow fiber membrane is: the membrane wall is densely covered with micropores, the raw liquid passes through one side of the membrane under a certain pressure, the solvent and small molecular solutes pass through the membrane wall to become the filtrate, and the macromolecular solutes are retained by the membrane to achieve material sep...

AI Technical Summary

Problems solved by technology

[0004] The above-mentioned methods for preparing hollow fiber membranes are usually complicated in equipment, large in investment, cumbersome in process and long in process. For example, a screw extruder is required to melt the polymer or complex spinneret components; a large amount of additives such as porogens need to be added during the preparation process, resulting in The obtained hollow fiber membrane has poor mechanical properties, high production cost and waste of resources