JPS60212414A - Acetylenic polymer and separating membrane consisting thereof - Google Patents

Abstract

PURPOSE:The titled novel polymer useful as a separating membrane for gases, etc. for separation and concentration of gases, having >=weight-average molecular weight of >=a specific value, obtained by polymerizing a substituted acetylene with a 1-alkyldimethylsilyl-1-propyne in a specific composition. CONSTITUTION:(A) A substituted acetylene (e.g., 2-decyne, etc.) shown by the formula I (R<1> is H, or alkyl; R<2> is alkyl) is copolymerized with (B) a 1-alkyldimethylsilyl-1-propyne (e.g., 1-trimethylsilyl-1-propyne, etc.) shown by the formula II, to give the desired polymer comprising 10-90mol% structural unit shown by the formula III and 90-10mol% structural unit shown by the formula IV, having >=10,000 weight-average molecular weight. The copolymer is dissolved in toluene, etc. to give a solution, a porous membrane is immersed in it so that the polymer is applied to the surface of the membrane, to obtain a separating membrane for gases.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a novel acetylenic polymer and a novel polymer material containing the same as a constituent.A second object of the present invention is to provide a novel acetylenic polymer and a novel polymer material containing the same as a constituent. The purpose of the present invention is to provide gas separation membranes used for separating or concentrating specific components.

According to the present invention, the first object is to have structural units represented by the following formulas (1) and (II), and whose allocation is such that the structural units of formula (1) are 7θ to 20 molti, and (
II) The structural unit represented by the formula is 90-/9 mol%
This is achieved using a polymer having a weight average molecular weight of 10,000 or more.

1 (In the above formula (1), R1 is a hydrogen atom or an alkyl group, and B2 is an alkyl group. Also, in the above (11)
) In the formula, Ra is an alkyl group. ) further agoHtj
The second objective "C" is achieved by the gas separation membrane using the above-mentioned polymer as a living body.

The present invention will be explained in detail below.

The polymer of the present invention has structural units represented by the following formulas (1) and (II), and the allocation thereof is represented by the structural units y, 6io to go molti of the formula (I), and the following formula (n). It is a polymer having a structural unit f90-10 mol and a weight average molecular weight of 1 Iti 10,000 or more. Preferably (1
) S structural unit and (II) structural unit are each 25 to 25
73 mol%, coS~75 mol.

+C-Csu......CI)1 1 nRsuo- In the above formula (1), R't'; is a hydrogen atom and a linear or branched chain having 1 to 6 carbon atoms. An alkyl group is chosen. RR is a linear or branched alkyl having 7 to 10 carbon atoms 2! III is selected, and these groups may have one or more of the hydrogen atoms of the group substituted with a substituent. Examples of the substituent include a halogen atom, an aryl group, an alkoxyl group, and aryloxy.

In the above formula (11), Rs is a linear or branched alkyl group having 1-da carbon atoms.

Of course, if the allocation is small, it may have structural units other than the structural units of the curved water (I) and (IIJ formulas).

However, this polymer has the following general formulas (1) and (1).
It can be obtained by copolymerizing the monomers represented by v).

B1− c = c −n” ・−−(1) (here
13, 12 and Rs are the front leg formula (1) and (11)
It is the same as the meaning in the ceremony. ) Specific examples of monomers include (English) formula: secondary or tertiary butylacetylene, tertiary-4LIJ: $opentylacetylene, cohexine, -monohebutene, λ-octene, cornonine, 2-decyne, q -Methyl-bentene, +, p'
-dimethyl-a-pentyne, ri, da'-cymeter-cohexine, j, j'-dimeter-hexine, 3-
Octyne, 3-nonine 1. ? Examples include -7'syn, Hiro-octene, and the like.

In formula (IV), /-)dimethylsilyl-l-propyne, no-ethyldimethylsilyl-7-propyne, /-n-
Propyldimethylsilyl-7-propyne, 1-i-7'
lobildimethylsilyl-7-bropine,/-n-butyldimethylsilyl-/-propyne47. -/-1-butyldimethylsilyl-1-propyne and the like.

Of course, a copolymer containing a small proportion of monomers other than monomers of formulas (1) and (y) may also be used.

From the monomers of formula (lid) and formula (ff) above, weight average molecule i! In order to obtain a chain polymer of 10,000 or more, niobium or tantalum halide catalysts are used. All of these catalysts are commercially available, and although they are hygroscopic, they are less effective than V-based polymers. It is a solid powder and easy to handle. Among those halogenated moieties, chloride and bromide in particular produce high molecular weight polymers in commercial yields. Iodide also shows considerable activity. Fluoride tends to produce chain oligomer by-products.

The appropriate amount of one catalyst to be used is usually 0.7 to 5 mol % based on the monomer.

The weighting reaction is preferably carried out in a solvent, and examples of such reaction include aromatic hydrocarbons such as toluene, aliphatic hydrocarbons such as cyclohexane, halogenated hydrocarbons such as tetrachloride, ethylene dichloride, etc. - The weighting temperature is not necessarily constant depending on the type of monomer, type of solvent-1, and other conditions, but is usually set between 50 and /jtO°C. The loading time is usually from several hours to several tens of hours. Polymerization is carried out under a dry nitrogen atmosphere.

After the reaction is complete, the reaction system is poured into methanol that has been diluted with the solvent used in the reaction, and the resulting polymer precipitates, which is then separated and dried.

By the above method, from the monomers of formulas (1) and (IV), formulas CI) and (n
) components of the formula are 10 to 90 molti and 90 molti, respectively.
10 molti or more, preferably -5 to 75 molti each and ? A new chain-like irises containing 5 mol% of j- to co can be obtained in the form of a sieve, and the polymer can be determined by gel permeation chromatography (hereinafter abbreviated as GPC) to the weight average molecular /10,000 or more, and has the characteristic of being completely soluble in hydrocarbons such as toluene and cyclohexane.◎ The produced polymer can be used as a material for a gas separation layer, which is the second objective of the present invention.

The film forming method is not particularly limited, but preferred film forming methods include coating a separately formed porous film, forming an anisotropic film consisting of a dense skin layer and a porous layer, and forming a separately formed porous film. There are a method in which a porous membrane is layered with a thin film with a high separation property, and a method in which a polymer bath solution is cast onto a glass plate or the like to evaporate the solvent to form a homogeneous membrane.

First, regarding the method of coating a porous membrane, the above-mentioned novel polymer is dissolved in an organic solvent, and a porous group consisting of another material, which is separately formed, is immersed in this solution. Dry the solvent.

The organic solvent used when dissolving the polymer to form a membrane forming solution is a low boiling point solvent that dissolves the polymer, is relatively easy to desolvent, and dissolves the porous membrane that will serve as the support. There are no particular restrictions on the name of the name. Depending on the type of porous membrane material,
Example Id, benzene, toluene, pentane, hexane,
Examples include heptane and tetrahydrofuran.

The porous membrane used in the present invention is a membrane with a sponge-like structure and open pores on both sides, or a membrane with a dense layer on one side and open pores on the other side. or a membrane with molecularly micro-ultra-fine pores in which the permeation rate of elemental gas is unit membrane area (/d), unit time (7 seconds), unit pressure difference (/CrrrHf).
Transmission amount/X 10-'cd/CTt ・@e
c - CWHf or more.

Such a membrane can be formed by various methods, for example, by adding an organic solvent or an additive to a porous membrane material and removing S, or by eluting the organic solvent or additive.

The type of porous material is not particularly limited, but examples include polypropylene, polyvinyl chloride, polystyrene, polyvinyl alcohol, polymethyl methacrylate, polyacrylonitrile, polycarbonate, polyphenylene oxide, polyamide, polysulfone, polyether sulfone, and polysulfone. amide, polypiperazine, polyimide, cellulose acetate, rhebutyric cellulose,
Examples include Teflon, vinylidene fluoride, polyvinyltrimethylsilane, and polymers containing a polyamino acid structure.

Inorganic materials such as glass can also be used.

The solution concentration when the polymer of the present invention is dissolved in an organic solvent and multinucleated into a porous membrane varies depending on the molecular weight and molecular weight distribution of the polymer and the type of solvent, but may be 0. /Mth 1% to 50 weight axe, preferably 1 weight axe to 1OX douche.

When the concentration is less than 0.1% by weight, the thickness of the membrane to be extracted becomes thinner, and the gas permeation rate is high, but the original separation performance cannot be obtained, and when the concentration is less than 50% by weight, In this case, the thickness of the membrane to be extracted becomes thicker, and while the separation performance is improved, the gas permeation rate becomes lower.

Usually the amount of polymer coated is 0.0.
0/~io~.

The thickness of the porous membrane is not particularly limited, but is 10μ to 10μ.
0μ is preferred.

The method of coating the porous membrane with the uninvented novel polymer solution is not particularly limited, but methods include immersing the porous membrane in a polymer bath solution, and casting a polymer solution on the surface of the porous membrane. I can do it.

Next, we will discuss the #membrane force method for anisotropic films.

Method for forming an anisotropic film The film can be formed according to the method for forming an anisotropic film of vinyltriorganosilane described in JP-A-4-2093.

(1) Supporting a solution in which the polymer is dissolved in a ternary mixture consisting of one type of solvent that has a boiling point difference of at least 30 C, has a boiling point higher than that of poly, and is a non-solvent for the polymer. (2) remove all or part of the light solvent; (3) remove all or part of the light solvent;
A film can be formed by a method comprising: treating the produced film with a coagulating liquid (non-solvent), and (4) drying the film.

Heavy solvents and heavy solvents include aliphatic and aromatic hydrocarbons such as cyclohexane, benzene and toluene, and dichloromethane, dichloroethylene, tetrachloroethylene,
Suitably selected from halogenated hydrocarbons such as chloroform, dichlorobenzene and monochlorobenzene.

Suitable non-solvents for the polymer include alcohols such as water, methanol, ethanol and primary, primary, and m-butanols, and ketones such as acetone, methyl ethyl ketone, and cyclohexanone.

The ratio of heavy solvent, heavy solvent, and non-solvent is
It must be such that it is soluble in the component system mixture and immovable (but possibly swellable) in the heavy solvent/nonsolvent mixture.

In addition, in order to overlay a separately produced thin film with separability on a porous gland, a polymer mixture is first spread on the water surface. The polymer solution spreads thinly on the water surface, and when the solvent evaporates, an extremely thin film of polymer is formed. Ultra-thin films are usually
Interference fringes are observed and thicknesses of less than lμ are easily obtained.

This thin film may be collected and laminated onto a porous support membrane to form a composite membrane.

The method for obtaining a homogeneous film is to form a film by casting a solution of a polymer dissolved in a good solvent onto a flat surface such as a glass plate.

In either case of depositing the nuclide on a porous membrane or forming an anisotropic membrane, (1) The shape of the membrane may be hollow fiber, tube, spiral, or flat plate. It can also be used in (If the nuclide is deposited on a porous membrane, the shape of the porous membrane should be selected.)
) A coating layer can be further laminated on the surface of the membrane of the present invention by plasma polymerization etc. (4) The permeation rate can be improved by mixing the new polymer of the membrane material with a polymer having a polysiloxane bond. I can do it.

The membranes of the invention can be used to separate gases from each other, in particular gas mixtures containing at least one of the following gases: oxygen, nitrogen, carbon dioxide, -carbon oxide, hydrogen, helium, methane, argon.

For example, separation of nitrogen and oxygen in the production of oxygen-enriched air, separation of methane and helium in the recovery of helium from natural gas, argon and hydrogen in the recovery of hydrogen from hydrogenation reaction exhaust gas, Separation of methane and hydrogen, storage and hydrogen, separation of -e carbon and hydrogen in the recovery of hydrogen from cranking gas, separation of carbon dioxide and nitrogen in the recovery of carbon dioxide from combustion gas, etc. It can be applied to

Next, the present invention will be explained in detail with reference to Examples, but the content of the present invention is not limited to the Examples.

Example 1 In a sufficiently purified toluene solution under a dry nitrogen atmosphere, 3.7 mmol of niobium pentachloride was added with thorough stirring and dissolved at 10°C. To this solution were added 009 mol each of copsin and/-trimethylsilyl-7-propyne, and the polymerization was allowed to proceed at Ir0C. 3 hours later
The reaction mixture was poured into a large amount of methanol to precipitate the resulting polymer, which was then dried separately. The yield of the polymer was 76% according to the xi method.

This product was subjected to GPCi measurement. The measurement conditions were a detector RI-f type manufactured by Toyo Soda, and a column TSK-G. r
000H1 000H, 3000H.

-100011,88 tetrahydrofuran, flow rate/t
d/mg, 31 C, Pressure Chemical (USA)
The results were calibrated using monodisperse polystyrene produced by the company, and all values were converted into polystere.The GPC measurement results of the product showed that the number average molecular weight and weight average molecular weight in terms of polystyrene were 600. and 6θO, and Mw/'MN was muco.

The resulting polymer was a pale yellow solid and dissolved in benzene, toluene, cyclohexane, n-hexane, tetrahydrofuran, and carbon tetrachloride.

The analytical values of the produced polymer were as follows.

Infrared absorption spectrum (unit: crn”): 3ooo~
Cot5θ (S included /16θ (m included /4A70~/41
Da0 (ml13ri0(m), lko5θ(1), /
/ 90 (rn included / /-〇A-1Oθθ(W included 92
θ(m included g Q O(s included t, oryrs included 6
za0~&'I 0(v), and the KONO00A-KOJOOcrI present in the monomer! The absorption of acetylene in ""1 has disappeared.

The proton signals in the NMR spectrum (/00 MHz, in deuterated chloroform) were as follows.

0.2 ppm...Methyl signal of trimethylsilyl group θ9 ppm...Terminal methyl signal of R (n-heptyl group) in formula (I) io~i! r ppm -CI) of the formula R(n-hep f
Methylene signal 1 except for one adjacent to the main chain of JLt group)! -Q/ppm --- Methyl signal units substituted in the main chain excluding R and 81R of formulas (i) and (II) ~29 ppm...R(n- However, one methicine signal adjacent to the main chain of the hebutyl group) is 0. ．． C from the peaks of 2 ppm and 0.9 ppm
Calculating the abundance ratio of formula I) and formula (It) (I): (I
t) -55 Nihiro 5.

Elemental analysis value C(I) CroH+a ・(Loss C6HH1
Si] Actual value 2λ to C near, H: /19, St
; 914 calculated value ((1): (n) = 5j when set to 5) C: 72ffJ, H; /L/9, st
;q, vq Practical implementation notes The copolymerization of copesin obtained in Example 1 and /-)limetersilyl-l-propyne is dissolved in toluene to form a solution of 1-cell solution, and a porous membrane [Millipore] is added to this solution. From the filter vswp, it was lbt/rW.

This composite membrane was attached to a permeation test device, and the permeation characteristics of various gases were measured. As a measurement device, an ultrafiltration device [manufactured by Amicon (Amicon, USA, Model Sλ)] was used. After attaching a membrane, a specified gas 'ljf/,
The membrane is pressurized at a pressure of Okf/C1/l G, the lower surface of the membrane is connected to a gas buret, and the gas permeating through the membrane is measured over a certain period of time to calculate the gas permeation rate. The results are shown in Tatsu-1.

The unit of gas permeation rate for various gases is -(STP)/cd
°sea °CrrrHf Teal.

The gas permeation performance of the Millipore filter-vswp used at this time was as follows. Gas permeation rate (cd
l/Cdt-1+ec-CmHf) N2-i?
X1o-”, 0, = 17×l0-2 gas permeation rate ratio (
O□/N, ) -0,92゜Example 3 The copolymer of copesin and l-trimethylsilyl-7-propyne obtained in Example 1 was dissolved in toluene to make a 1% by weight solution and heated to 3°C. Hold.

The polymer solution is added dropwise with a micropipette to water previously filled in a container and maintained at 72°C. The average weight of the droplets at this time was 12 J da.

The added droplets immediately spread on the water surface, resulting in an extremely thin circular film. At this time, the membrane area ulq ct
/l, and the film thickness calculated from this using the gravimetric method is 0. It is tμ. The ultrathin membrane obtained here was taken out onto a porous membrane (Millipore filter-vswp) to produce a composite membrane. The gas permeation rate of this composite @-membrane was measured in the same manner as in Example C. The results are shown in Table-7.

Claims (1)

[Claims] fl) It has structural units represented by the following formulas (1) and (11), and the proportion of the structural units of formula (1) is 70-
90 molar ratio, and the structural unit of formula (II) is 'yo-i
o mole ax, a polymer having a weight average molecular weight of 10,000 or more (in the above formula (1), R1 is a hydrogen atom or an alkyl group, and R1 is an alkyl group. and R3 is an alkyl group.) (2) It has a structural unit represented by the following formula (1) and (Kawa) formula, and the ratio of the structural units of formula (1) is 10-9
0 mol%, and a polymer having an average molecular weight of 10,000 or more and having a structural unit of formula (II) of 90-10 mol% (in the above formula (I), R' is a hydrogen atom or an alkyl group, and 12 is an argyl group) (In formula (11), R3 is an alkyl group.)