JPS62110729A - Permselective compound film for gas - Google Patents

Abstract

PURPOSE:To improve separability and permselectivity for gas of permselective compound film for gas by allowing electrolytically oxidized or reduced polymer to be present on the surface or in the inside of amorphous polymer film having uniform or fine porous structure and >=180 deg.C glass transition point. CONSTITUTION:Permselective compound film is prepd. by forming oxidized or reduced body of polymer by electrolytic process on the surface or in the inside of amorphous polymer film having uniform or fine porous structure and >=180 deg.C glass transition point. Preferred amorphous polymer is acetylenic polymer expressed by the formula I (where R1 is H atom, halogen atom, or alkyl group; R2 is trialkylsilyl group, alkyl group, or phenyl group). Preferred electrolytically oxidized or reduced polymer is pyrrole or a reduced product thereof expressed by the formula II (where X is BF4, ClO4, SO4, AsF6, I, etc.).

Description

[Detailed description of the invention] Industrial applications The present invention relates to a selective gas permeable composite membrane.

2. Description of the Related Art Recently, the use of selective gas permeable membranes to separate and concentrate gas mixtures has been actively studied. For example, oxygen-enriched air can be obtained by selectively permeating oxygen from air, and it can be used in combustion systems or medical applications. Furthermore, it can be synthesized by steam reforming, thermal decomposition, etc. using coal, natural gas, etc. as raw materials. Application to C1 chemical separation membranes that selectively permeate hydrogen from gas or waste gas from steel plants, separate it from gases such as carbon monoxide and methane, purify it, and use these gases, and furthermore, from natural gas. Recovery of helium by selective permeation of The properties required of the selective gas permeable membranes used in these applications are that they have high gas selectivity and gas permeability, high heat resistance, high mechanical strength, and chemical resistance.

Problems to be Solved by the Invention 11. The gas permeability characteristics of a single molecule are generally such that as the gas permeability increases, the selectivity decreases, and the force selectivity decreases. Selectivity and permeability are in a contradictory relationship; the larger the value, the lower the permeability.

For example, PO II trimedylsilyl spout pin (PMSP), which has excellent gas permeability, has an oxygen permeability coefficient of 1'02 of 1.6.
It exhibits a very high permeability of 0XIOcc-m/cd-scc-ml1g, but on the other hand, the permeability coefficient ratio α of oxygen and nitrogen is as low as about 1.4. This material has the second highest permeability after the old 4U*'
Silicone rubber is known as 1, but the P of this material
O2 is 6. OX 10' CC-m Otsu Hd -scc
-mllg and α is approximately 2.0.

Polyphenylene oxide (,1,"I)O) is a material with excellent selectivity for these monthly materials. α of this material is about 4.0, which improves the selectivity by about twice, while its permeability is 1.'02-'2.8X100-9cc-/c
It will be as low as 4.scc-ml1g.

A polymer with such excellent gas selectivity and permeability does not yet exist, and therefore applications are currently being developed based on the gas and body permeability of selectively permeable membranes.

The present invention is intended to solve the above-mentioned problems, and aims to provide a selective gas permeable composite membrane that is excellent in both gas separation properties and gas permeability.

Means for Solving the Problems The present invention has been made to achieve the above object, and the present invention has been made in order to achieve the above object.
The present invention provides a selective gas permeable composite membrane in which an electrolytically polymerized polymer is present on the surface or inside the amorphous polymer membrane described above.

Function The present invention has such a structure, thereby providing a composite membrane with high gas permeability and high separation performance.

That is, the oxygen permeability coefficient is 10. '77-1O-9cc-
/d-seccmHg order, and the permeability coefficient ratio of oxygen and nitrogen (P02/PN2) α was 3.0 to 7.0, showing revolutionary characteristics not found in conventional materials.

The amorphous polymer membrane material of the present invention has the following general formula:
Suitable are acetylene polymers, polyphenylene oxides, or polysulfones (selected from the group consisting of alkyl groups and phenyl groups), while electrolytically polymerized polymers include polypyrrole, polyaniline, or polydiophene oxidized or reduced forms. is preferable.

Further, the electrolytically polymerized polymer may be provided on the surface or inside of the amorphous polymer membrane, and the electrolytic polymerization method can be used to selectively produce either an oxidized form or a reduced form of the polymer.

Example Examples of the present invention will be described in detail below.

Polytrimethylsilylpropyne (weight average molecular weight Mw ÷ 600,000) (PM, 81 mm) was used as the polymer membrane material, and after preparing a 4% by weight toluene solution of this material, 7 pages/Nesa glass plate with a uniform surface was obtained by the casting method. A film is formed on top of the Nesa glass plate.Then, the end of this Nesa glass plate that is not covered with the PMSP film is coated with a room temperature curing silicone adhesive for sealing, and then used as an electrode for electrolytic polymerization.Acrylonitrile is used as the electrolytic polymerization solution. The composition was 1 mole of pyrrole as a solvent and 0.25 mole of tetrabutylammonium barcrosheet as an electrolyte.A platinum plate was used as a counter electrode, and electrolysis was performed using the electrolytic polymerization solution as an anode.
A composite membrane of SP and electrolytic polymer was produced. The film thus obtained had a black color and the Nesa surface area provided a composite membrane exhibiting conductivity. Gas permeability is oxygen permeability coefficient po
2 is about 4. OX 10' cc - cm/cdl -
α(Po2/PN2) is 5.0 for sec-cmI-Ig
reached.

Furthermore, even after the composite membrane was reduced under the same conditions, this gas permeability remained almost unchanged.

The table below shows the results when the amorphous polymer and electrolytic polymer were changed under the same conditions.

In both cases, high oxygen permeability coefficients and high permeability coefficient ratios were obtained.

The amorphous polymer of the present invention only needs to have a glass transition temperature of 180° C. or higher, and in this case, the presence of microvoids allows the electrolytic polymer to be trapped inside or on the surface, making it possible to form a composite.

Effects of the Invention In short, the present invention provides a selective gas permeable composite membrane in which molecules of a monomer polymer are present on the surface or inside of a homogeneous or microporous amorphous polymer membrane having a glass transition temperature of 180°C or higher. By doing so, a selective gas permeable composite membrane having high gas permeability and high separation property can be obtained.

Claims (7)

[Claims] (1) Homogeneous or microporous glass transition temperature is 180℃
A selective gas permeable composite membrane characterized in that an electrolytically polymerized polymer is present on or inside the amorphous polymer membrane described above. (2) The general formula of the amorphous polymer film is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, R_1 is a hydrogen atom, halogen atom, or alkyl group, R_2 is a trialkylsilyl group,
The selective gas permeable composite membrane according to claim 1, which is an acetylene polymer represented by an alkyl group or a phenyl group. (3) The selective gas permeable composite membrane according to claim 1, wherein the amorphous polymer membrane is polyphenylene oxide. (4) The selective gas permeable composite membrane according to claim 1, wherein the amorphous polymer membrane is polysulfone. (5) The general formula of electropolymerized polymers is ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (However, X is the counter ion of the oxidized polymer, BF_4
, ClO_4, SO_4, BF_3, AsF_6, I,
The selective gas permeable composite membrane according to claim 1, which is polypyrrole (selected from the group consisting of Br, I_2) or its reduced form. (6) The selective gas permeable composite membrane according to claim 1, wherein the electrolytically polymerized polymer is either an oxidized or reduced polyaniline. (7) The selective gas permeable composite membrane according to claim 1, wherein the electrolytically polymerized polymer is either an oxidized or reduced polythiophene.