JPS618104A - Sterilizable porous polyolefin hollow yarn - Google Patents

Abstract

PURPOSE:To obtain a sterilizable polyolefin hollow yarn excellent in safety and sanitariness, by fixing a water-insoluble silver-containing porous polyacrylonitrile macromolecular thin film on the surface of the laminated structure of porous polyethylene. CONSTITUTION:A porous polyethylene hollow yarn, which has such a laminated structure that minute voids are mutually connected from the inner wall surface of the hollow yarn to the outer wall surface thereof, is obtained and impregnated with an org. solvent solution containing an acrylonitrile type polymer containing a water-insoluble acidic group while the impregnated one is immersed in water and quick wet coagulation treatment is performed to form a water-insoluble acrylonitrile porous film. Succeedingly, this hollow yarn is immersed in an aqueous silver nitrate solution and subsequently treated with an aqueous reducing agent solution to obtain a sterilizable hollow yarn wherein a water-insoluble silver-containing porous acrylonitrile macromolecular thin film is fixed to the surface of the laminated structure of a porous polyethylene hollow yarn.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to porous polyolefin hollow fibers with excellent bactericidal properties.

[Background technology]

2. Description of the Related Art A wide variety of devices have been proposed as deionized water production devices for use in medical, pharmaceutical, food industry, precision industry, physical and chemical experiments, and other fields.

That is, there are pure water producing apparatuses that do not contain colloidal substances or bacteria, furthermore, pure water producing apparatuses that do not contain pyrogenic substances, and pure water producing apparatuses that do not contain radioactive substances. For example, sterile water production equipment in the medical field includes equipment using the lid method, boiling sterilization equipment, and ultraviolet sterilization equipment, but energy costs and equipment costs are high, sterilization is insufficient, and colloidal water production equipment is available. Some devices have drawbacks, such as being able to remove substances and bacteria, but not pyrogens.

-Recently, reverse osmosis membrane equipment has begun to be adopted to overcome all of these drawbacks, but reverse osmosis equipment requires high pressure, resulting in high equipment and energy costs.

Under these circumstances, the present applicant has solved the drawbacks of conventional devices and has developed a porous hollow fiber suitable for precision f-filtration devices that has low equipment costs and energy costs, has a simple structure, is less likely to break down, and is highly reliable. We proposed a porous polyolefin hollow fiber with a laminated structure in which micropores are interconnected from the inner wall surface of the hollow fiber to the outer wall surface. However, although porous polyolefin hollow fibers completely block bacterial permeation, they do not have sterilizing properties, so modules using these hollow fibers can gradually accumulate bacteria that are not filtered inside. There is a risk of multiplication, which is undesirable from a safety and hygiene perspective, and there is a strong demand for the development of porous polyolefin hollow fibers with excellent bactericidal properties.7'2
-O [Object of the Invention] An object of the present invention is to provide a porous polyolefin hollow fiber that is safe, hygienic, and sterilizing.

[Structure of the invention]

In the present invention, micropores are interconnected from the inner wall surface of the hollow fiber to the outer wall surface, and the layered structure surface of the porous polyolefin hollow fiber has a layered structure.
The present invention relates to a bactericidal porous polyolefin hollow fiber characterized by having an IJ-based polymer thin film adhered thereto. Polyolefins include polyethylene and polypropylene.

Polytetrafluoroethylene or the like can be used.

Taking polyethylene as an example of polyolefin, a porous polyethylene hollow fiber having a laminated structure in which micropores are interconnected from the inner wall surface to the outer wall surface of the hollow fiber can be obtained, for example, in Japanese Patent Application No. 55-116263.

A method for obtaining permanently sterilizing porous polyethylene hollow fibers by solidifying a water-insoluble silver-containing porous acrylonitrile polymer thin film on the surface of the laminated structure of the porous polyethylene hollow fibers includes, for example, using water-insoluble acidic groups. 2) After a porous polyethylene hollow fiber is impregnated with an M solvent solution containing an IJ-based polymer, it is immersed in water, which is a coagulant for the polymer, and subjected to a rapid wet coagulation treatment. A water-insoluble acrylonitrile porous membrane can be formed and firmly adhered to the surface of a laminated structure of porous polyethylene hollow fibers.

Subsequently, the porous polyethylene hollow fiber to which the water-insoluble acrylonitrile porous membrane containing acidic groups is fixed is immersed in an aqueous solution containing nitric acid, so that silver is added to the acidic groups in the acrylonitrile porous membrane. A porous polyethylene hollow fiber with ions adsorbed thereon is obtained.

Furthermore, by treating this fiber with an aqueous reducing agent solution, C-metallic silver is generated, and a water-insoluble silver-containing porous acrylonitrile polymer membrane is fixed to the surface of the laminated structure of the porous polyethylene hollow fibers. A hollow fiber is obtained.

Furthermore, silver exhibits excellent bactericidal properties, and using an appropriate method, silver can purify approximately 10 million times its weight in water. It is well known that water becomes sterile.

Therefore, a very small amount of silver adheres to the surface of the laminated structure of porous polyolefin hollow fibers, just like in the case of silver products!
It exhibits excellent bactericidal properties.

The bactericidal porous polio hollow fiber of the present invention can be made into a module by directly applying a general known module manufacturing method using porous hollow fiber.
This module may be of any type as long as the liquid or gas is filtered from the outer wall surface to the inner wall surface or from the inner wall surface toward the outer wall surface of the porous hollow fibers.

The sterilizing porous polyolefin hollow fiber of the present invention is capable of removing colloidal substances, bacteria, and pyrogenic substances, and the module using the hollow fiber can remove bacteria remaining on the surface without being filtered. is sterilized by silver, ensuring safety and hygiene at all times.Compared to conventional equipment, equipment costs and energy costs are lower, the structure is simple, and there are fewer breakdowns.
This enables highly reliable precision filtration.

〔Example〕

The present invention will be explained below with reference to Examples, and the bactericidal properties were measured by the following method.

(Measurement of bactericidal properties) The test sample was placed on an agar medium seeded with Staphylococcus aureus, and the bacteria was cultured at 37°C for 24 hours. The bactericidal effect was determined by the presence or absence of growth of Staphylococcus around the sample. to make a profit.

(flJ determination) ○: No bacterial growth was observed around the sample, and a halo was generated.

Δ: No bacterial growth is observed around the sample, and no halo is generated.○×: Bacterial growth is observed around the sample.

Example 1 Acrylonitrile 93% by weight, vinyl acetate 7% by weight,
Sulfo/acid group 50 m, mol/91. A porous polyethylene hollow fiber FiHF (trade name,
(manufactured by Mitsubishi Rayon Co., Ltd.), the solution was squeezed out, the amount of solution adhering to the hollow fiber was 220% owf, and then 6
After immersing in 0°C hot water to make the acrylonitrile polymer porous by rapid solidification treatment and remove solvent,
After thorough washing with water, a porous polyethylene hollow fiber having an acrylonitrile porous membrane adhered to the surface of the multilayer structure of the hollow fiber was obtained. Subsequently, this hollow fiber was immersed in an aqueous solution at 25°C containing 1% by weight of silver nitrate to bond silver ions to the acidic groups in the porous acrylonitrile membrane, and then taken out and placed in an aqueous solution containing 1% by weight of hydrazine hydrate at 25°C. After reduction treatment by immersing in an aqueous solution of A hollow fiber was obtained that was fixed. Continued hollow fiber 100
The entire fiber was bundled into a U-shape and the entire opening of the hollow fiber was solidified with resin to create a module with a length of the resin-embedded portion of 4 cm and an effective length of the hollow fiber of 10 crn.

Using this module, the pressure is 380+ from the outer wall of the middle 9 threads.
As a result of measuring the flow velocity of water under ++ mHg, the decrease in f water velocity was extremely small compared to a module made using the same method as a comparative example using porous polyethylene hollow fibers that had not undergone any of the above treatments. Ta.

Furthermore, the hollow fibers were taken out and the relationship between the amount of F water and the bactericidal activity against Staphylococcus aureus was measured, and the following results were obtained.

Although the tyrene hollow fibers do not have bactericidal properties, the threads have excellent permanent bactericidal properties when inserted into the porous polyethylene to which the silver-containing porous acrylonitrile polymer thin film of the present invention is adhered. Even after 1000 filtration, no bacterial growth was observed around the sample, indicating excellent bactericidal properties with halo formation.

Claims (1)

[Claims] The micropores are interconnected from the inner wall of the hollow fiber to the outer wall,
A bactericidal porous polyolefin hollow fiber having a laminated structure, characterized in that a water-insoluble silver-containing porous acrylonitrile polymer thin film is adhered to the surface of the laminated structure of the porous polyolefin hollow fiber.