JPH0582407B2 - - Google Patents

Description

[Detailed description of the invention]

FIELD OF THE INVENTION The present invention relates to a novel substituted acetylenic copolymer comprising monomer units formed from 1-trimethylsilylpropyne units and other substituted acetylenes. The copolymer of the present invention is a novel copolymer that has not yet been published in any literature, and provides a high-performance substance separation membrane with excellent both substance permeation performance and substance separation ability, which is used, for example, to separate gas mixtures or liquid mixtures. It is useful as a material for Particularly in recent years, the use of gas separation methods using membranes has been rapidly expanding due to their energy saving, high safety, and ease of operation. Furthermore, in particular, oxygen-enriched air with an oxygen concentration of 25% or more can be effectively used, for example, in various combustion engines, medical equipment, the food industry, waste treatment, etc., and can be manufactured efficiently. A method is needed. [Prior Art] Conventionally, as a method for separating gas mixtures, a cryogenic separation method that utilizes the difference in boiling points between gases has been generally used. However, since the cryogenic separation method uses a phase change of the gas, it consumes a large amount of energy, or the gas produced and stored in a pressure vessel is dangerous, and the operation is complicated. Various problems arose. In recent years, it has become more economical than such methods;
Separation methods using polymer membrane permeation are attracting attention as a method with excellent safety and ease of operation.
In other words, it attempts to separate or concentrate one or more components of a mixed gas by utilizing the difference in the rate at which gas permeates through a polymer membrane.It is particularly useful for producing oxygen-enriched air. It is expected. The properties particularly required for a membrane used for oxygen enrichment are: 1 Oxygen permeability coefficient Po ₂ (Hereinafter, unless otherwise specified, the unit of permeability coefficient is cm ³ (STP).
Use ^cm2・sec・cmHg. ) is large 2 Separation ability of oxygen and nitrogen, that is, separation coefficient α
(= Oxygen permeability coefficient Po ₂ / Nitrogen permeability coefficient P _N2 )
3. It must have sufficient workability to prevent pinholes or cracks even as a thin film. Conventionally, polydimethylsiloxane or poly(1-trimethylsilipropyne) (T.Am.
Chem.Soc.1983, 105 , P.7473), but the former has a membrane of several tens of μm due to its low mechanical strength.
If it is less than m, it is impossible to obtain a membrane that can withstand actual use, and the latter has the drawback that α=1.7, which has extremely poor separation ability and makes it impossible to obtain air with a sufficient oxygen concentration. Polydimethylsiloxane-polycarbonate block copolymer (U.S. patent
3980456, 3874986), polydimethylsiloxane copolymer (Japanese Unexamined Patent Publication No. 56-26504), etc., attempts have been made to increase the strength by copolymerization, but a significant decrease in permeability is inevitable. Thus, to date, no polymer has been known that can be used as a membrane material that satisfies all the performance requirements for membranes used to separate gas mixtures. [Problems to be Solved by the Present Invention] The present invention is directed to a novel copolymer that can be used as a membrane material that has excellent permeability and separation ability, and has excellent strength, which can solve the drawbacks of the conventional gas separation membranes mentioned above. It provides integration. [Detailed Description of the Invention] The present inventors have conducted extensive research in search of a membrane material that has excellent selective permselectivity for gases, particularly oxygen gas, and has sufficient mechanical strength to allow for thinning. As a result, when a new copolymer of 1-trimethylsilylpropyne and various other substituted acetylenes is used as a membrane material, it has a gas permeability comparable to that of poly(1-trimethylsilylpropyne). ,
Furthermore, the present inventors discovered that a membrane having selective oxygen permeability far superior to that of the same polymer can be obtained, leading to the completion of the present invention. That is, the present invention provides structural formula

[ka] Repeating unit and general formula indicated by

[In the formula, R′ is a hydrogen atom, a halogen atom, an alkyl group, or a substituted alkyl group, and R ² is a phenyl group,
Substituted phenyl group, alkyl group, substituted alkyl group,
or expression

It represents a group represented by the formula (R ³ and R ⁴ each independently represent an alkyl group or a substituted alkyl group, and R ⁵ represents a substituted alkyl group, a phenyl group, or a substituted phenyl group). ] This relates to a copolymer formed from repeating units represented by. A commercially available monomer can be used as 1-trimethylsilylpropyne, which is a monomer used to obtain a copolymer having repeating units represented by structural formula (1) and general formula (2). In addition, the general formula R ¹ -C≡C-R ² (3) used as a comonomer during copolymerization [wherein R ¹ is a hydrogen atom, a halogen atom, an alkyl group, or a substituted alkyl group, and R ² is a phenyl group] ,
Substituted phenyl group, alkyl group, substituted alkyl group or formula

A group represented by [Formula] (R ³ and R ⁴ are each independently an alkyl group or a substituted alkyl group,
R ⁵ represents a substituted alkyl group, phenyl group, or substituted phenyl group. ) represents. Some of the substituted acetylene monomers represented by ] are commercially available, and among these, silyl-substituted acetylene compounds can be synthesized in good yield by reaction of substituted acetylene compounds and chlorosilane compounds. for example

The following reactions can be exemplified. The substituted acetylene monomers represented by the general formula (3) used in the present invention include HC≡(-CH ₂ -) ₂ CH ₃ , HC≡C-CH(CH ₃ ) ₂ , HC
≡CC(CH ₃ ) ₃ , HC≡C(-CH ₂ -) ₃ CH ₃ , HC≡(-CH ₂ -) ₃ CF ₃ , HC≡C(-CH ₂ -) ₂ CF ₂ CF ₃ , CH ₃ C≡C (-CH ₂ -) ₅ CH ₃ , ClOH ₂ C≡C-CH
(CH ₃ ) ₂ , BrCH ₂ C≡C (-CH ₂ -) ₇ CH ₃ , CH ₃ C≡C (-CH ₂ -)
₂ Si(CH ₃ ) ₃ , CH ₃ C≡CCH ₂ CH ₂ CF ₃ , CH ₃ CH ₂ C≡
CCH ₂ CH ₂ CF ₃ ,

[ka]

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〔Effect of the invention〕

As described above, since the polymer membrane obtained from the copolymer of the present invention has extremely excellent selective perms and membrane-forming properties, it is possible to remove oxygen from the air by using the copolymer of the present invention. Separation and concentration of various gas mixtures or liquid mixtures, such as enrichment, can be performed extremely efficiently. Moreover, by adjusting the composition of this copolymer, the selective permeation performance of the resulting polymer membrane can be freely controlled. The present invention will be explained in more detail below using Examples and Reference Examples. However, it goes without saying that the present invention is not limited to these.
In the Examples, the gas permeability coefficient was measured using a high vacuum pressure method. Reference example 1 (Synthesis of comonomer) 72g of propyne gas was added in a three-necked flask.
Dissolved in THF400ml and under argon gas atmosphere.
After cooling to 78℃, 400ml of n-butyllithium hexane solution (1.61M) was slowly added dropwise to the solution, and after the addition was completed, phenyldimethylchlorosilane was added.
98.9 g was added and the reaction was further carried out at -78°C for 1 hour. Thereafter, only the organic layer was taken out from the reaction solution, washed with pure water, dried using magnesium sulfate, and distilled under reduced pressure. As a result, 94.6 g of 1-phenyldimethylsilylpropyne (yield 93.7%, boiling point 70-72
°C/2 mmHg) was obtained. Example 1 1-trimethylsilylpropyne and Reference Example 1
The total monomer concentration was 1-phenyldimethylsilylpropyne obtained in
Dissolve tantalum pentachloride and tetraphenyltin in toluene to a concentration of 1.0M, and add 20mM each of tantalum pentachloride and tetraphenyltin.
The mixture was added at a concentration of 1,000 ml, poured into a glass ampoule, and after being degassed and sealed, the tube was shaken at 80°C for 24 hours to obtain a viscous gel-like polymer. This polymer was dissolved in toluene and reprecipitated several times in multiple methanol. After drying, perform IR, NMR and elemental analysis to determine the repeating unit.

[expression] and

It was confirmed that it was a copolymer consisting of [Formula], and its composition was calculated from the carbon content in elemental analysis, and the content of the latter repeating unit was 19 mol%. Further, as a result of GPC measurement, the weight average molecular weight of the copolymer was 5.43×10 ⁵ in terms of polystyrene.
The obtained copolymer was redissolved in toluene, the solution was cast on a Teflon plate, and the toluene was removed by evaporation to obtain a homogeneous membrane with a membrane thickness of 21 μm. Table 1 shows the measurement results of the oxygen and nitrogen permeability coefficients of this membrane at 25°C. In addition, this copolymer
The IR spectrum data and elemental analysis values were as follows. IR spectrum: 3100~2850(s), 1660~1610
(s, characteristic absorption by phenyl group on silyl group),
1520(s), 1450(m), 1340(s, characteristic absorption due to side chain methyl group), 1260(s, characteristic absorption due to Si-C bond), 1190(s), 1120(w), 1090(m) , 1000(s), 930(s),
850(s)cm ^-1 Elemental analysis value: C67.28%, H10.08% Examples 2 to 4 The molar ratio of 1-trimethylsilylpropyne and 1-phenyldimethylsilylpropyne was 80/
Polymerization and purification was carried out in exactly the same manner as in Example 1, except that the ratios were 20, 50/50, and 30/70. The composition of the obtained copolymer was calculated from the carbon content of elemental analysis.

The content of repeating units represented by the formulas was 11 mol%, 31 mol%, and 45 mol%, respectively. In addition, the weight average molecular weights of these copolymers are 6.95×10 5 and 6.95×10 ⁵ in terms of polystyrene, respectively.
They were 3.60×10 ⁵ and 2.87×10 ⁵ . These copolymers were formed into films in the same manner as in Example 1 to obtain homogeneous films with film thicknesses of 24 μm, 18 μm, and 32 μm, respectively. Table 1 shows the measurement results of the oxygen and nitrogen permeability coefficients of this membrane at 25°C. Reference Example 2 (Synthesis of comonomer) The same operation as in Reference Example 1 was carried out using 3,3,3-trifluoropropyldimethylchlorosilane instead of phenyldimethylchlorosilane, and 1(3,3 ,3-trifluoropropyldimethylsilyl)propyne (boiling point 50-52
°C/24 mmHg) with a yield of 85.2%. Example 5 1-trimethylsilylpropyne and Reference Example 2
1(-3,3,3-trifluoropropyldimethylsilyl)propyne obtained in step 1 was dissolved in toluene at a molar ratio of 65/35 so that the total monomer concentration was 1.0M, and tantalum pentachloride and tetraphenyl After adding tin at a concentration of 20 mM, polymerization and purification were performed in the same manner as in Example 1. After drying,
Perform IR, NMR and elemental analysis and repeat unit

[expression] and

After confirming that it is a copolymer consisting of [formula], we calculated this composition from the carbon content of elemental analysis, and found that the content of the latter repeating unit was
It was 25 mol%. In addition, as a result of GPC measurement, the weight average molecular weight of the copolymer was calculated as a polystyrene equivalent value.
It was 4.92× ¹⁰⁵ . The obtained copolymer was formed into a film in the same manner as in Example 1 to obtain a homogeneous film having a thickness of 15 μm. 25 of this membrane
Table 1 shows the measurement results of oxygen and nitrogen permeability coefficients at °C. Further, the IR spectrum data and elemental analysis values of this copolymer were as follows. IR spectrum: 3100~2850(s), 1570~1530(s),
1450(s), 1380 (s, characteristic absorption due to side chain methyl group), 1320(m), 1260 (characteristic absorption due to s3Si-C bond), 1190(s), 1120 (s, characteristic absorption due to C-F bond) ), 1060(m), 1020(s), 930(s), 900(s), 840(m),
800(w), 740(m), 650(w)cm ^-1 Elemental analysis values: C58.79%, H9.32% Examples 6, 7 1-trimethylsilylpropyne and 1(-3,3,
The molar ratio of 3-trifluoropropyldimethyldimethylsilyl)propyne was 82/18 and 40/60, respectively.
Polymerization and purification were carried out in exactly the same manner as in Example 5, except that. The composition of the obtained copolymer was calculated from the carbon content of elemental analysis.

The content of repeating units represented by the formulas was 7% and 48%, respectively. Furthermore, the weight average molecular weights of these copolymers were 5.62×10 ⁵ and 3.89×10 ⁵ , respectively, in terms of polystyrene.
These copolymers were formed into films in the same manner as in Example 1 to obtain homogeneous films with film thicknesses of 22 μm and 35 μm, respectively. Table 1 shows the measurement results of the oxygen and nitrogen permeability coefficients of these films at 25°C. Example 8 1-Trimethylsilylpropyne and 1-phenylpropyne (commercially available) were dissolved in toluene at a molar ratio of 30/70 so that the total monomer concentration was 1.0M, and tantalum pentachloride was added at a concentration of 20mM. Thereafter, polymerization and purification were performed in the same manner as in Example 1. After drying, perform IR, NMR and elemental analysis.
repeat unit

[expression] and

It was confirmed that it was a copolymer consisting of [Formula], and its composition was calculated from the carbon content in elemental analysis, and the content of the latter repeating unit was 35 mol%. Also,
As a result of GPC measurement, the weight average molecular weight of the copolymer is
The polystyrene equivalent value was 2.37×10 ⁵ . The obtained copolymer was formed into a film in the same manner as in Example 1 to obtain a homogeneous film with a thickness of 23 μm. 25℃ of this membrane
Table 1 shows the measurement results of oxygen and nitrogen permeability coefficients. Further, the IR spectrum data and elemental analysis values of this copolymer were as follows. IR spectrum: 3050(m), 2960(s), 2900(s),
2850 (m), 1750 (m), 1600 (m, characteristic absorption due to phenyl group), 1560 (s), 1450 (s), 1380 (s, characteristic absorption due to side chain methyl group), 1260 (s, Si- Characteristic absorption due to C bond), 1190(m), 1080(m), 1020(m), 910(s),
820(s), 750(s), 690(s), 930cm ^-1 (m) Elemental analysis values: C74.40%, H9.48% Examples 9, 10 Molar ratio of 1-trimethylsilylpropyne and 1-phenylpropyne Polymerization and purification were carried out in exactly the same manner as in Example 8, except that the ratios were changed to 50/50 and 20/80, respectively. The composition of the obtained copolymer was calculated from the carbon content of elemental analysis.

The content of repeating units represented by [Formula] was 10% and 45%, respectively. Moreover, the weight average molecular weights of these copolymers were 4.12×10 ⁵ and 2.21×10 ⁵ , respectively, in terms of polystyrene. These copolymers were formed into films in the same manner as in Example 1 to obtain homogeneous films with film thicknesses of 15 μm and 19 μm, respectively. Table 1 shows the measurement results of the oxygen and nitrogen permeability coefficients of these films at 25°C. Reference Example 3 (Synthesis of comonomer) In Reference Example 1, using pentafluorophenyldimethylchlorosilane instead of phenyldimethylchlorosilane, the same operation as in Reference Example 1 was performed to obtain 1(-pentafluorophenyldimethylsilyl). Propyne (boiling point 75-76℃/8mmH0) 95.3
% yield. Example 11 1-trimethylsilylpropyne and Reference Example 3
1-(pentafluorophenyldimethylsilyl)propyne obtained in 1-(pentafluorophenyldimethylsilyl)propyne was dissolved in toluene at a molar ratio of 70/30 so that the total monomer concentration was 1.0M, and tantalum pentachloride and tetraphenyltin were each dissolved at a concentration of 20mM. After addition, polymerization and purification were carried out in the same manner as in Example 1. After drying, perform IR and elemental analysis to determine the repeating unit.

[expression] and

It was confirmed that it was a copolymer consisting of [Formula], and its composition was calculated from the carbon content in elemental analysis, and the content of the latter repeating unit was 20 mol%. Further, as a result of GPC measurement, the weight average molecular weight of the copolymer was 2.04×10 ³ in terms of polystyrene. The obtained copolymer was formed into a film in the same manner as in Example 1 to obtain a homogeneous film having a thickness of 18 μm. 25℃ of this membrane
Table 1 shows the measurement results of oxygen and nitrogen permeability coefficients. The IR spectrum data and elemental analysis values of this copolymer were as follows. IR spectrum: 3150~2850(s), 1600~1530(s),
1450(s), 1420(w), 1380 (s, characteristic absorption due to side chain methyl group), 1260 (s, characteristic absorption due to Si-C bond), 1190(s), 1120 (s, characteristic absorption due to C-F bond) Characteristic absorption), 1020(m), 930(s), 860-810(s), 760(s), 650(s)
cm ^-1 elemental analysis value: C58.73%, H8.07% Reference Example 4 (Synthesis of comonomer) Using 2-pentafluorophenylethyldimethylchlorosilane in place of phenyldimethylchlorosilane in Reference Example 1, a reference example Perform exactly the same operation as in 1 to obtain 1(-2-pentafluorophenylethyldimethylsilyl)propyne (boiling point 90-92
℃/4 mmHg) with a yield of 91.5%. Example 12 1-trimethylsilylpropyne and Reference Example 4
1(-2-pentafluorophenylethyldimethylsilyl)propyne obtained in step 1 was dissolved in toluene at a molar ratio of 67/33 so that the total monomer concentration was 1.0M, and tantalum pentachloride and tetraphenyltin were dissolved in toluene. After adding each at a concentration of 20 mM, polymerization and purification were performed in the same manner as in Example 1. After drying,
Perform IRNMR and elemental analysis and repeat unit

[expression] and

It was confirmed that it was a copolymer consisting of [Formula], and its composition was calculated from the carbon content in elemental analysis, and the content of the latter repeating unit was 20 mol%. Also
As a result of GPC measurement, the weight average molecular weight of the copolymer was 2.65×10 ⁵ in terms of polystyrene. The obtained copolymer was formed into a film in the same manner as in Example 1 to obtain a homogeneous film with a thickness of 12 μm. Table 1 shows the measurement results of the oxygen and nitrogen permeability coefficients of this membrane at 25°C. Further, the IR spectrum data and elemental analysis values of this copolymer were as follows. IR spectrum: 3100~2850(s), 1670(w), 1590
~1510(s), 1450(s), 1380(s, characteristic absorption due to side chain methyl group), 1280(w), 1260(s, characteristic absorption due to Si-C bond), 1190(s), 1130(s , characteristic absorption due to C-F bond), 1000(m), 930(s), 880-750(s), 700
(s), 650(s)cm ^-1 Elemental analysis value: C59.96%3H8.40%

[Table] The units of Po ₂ and P _N2 in Table 1 are cm ³
(STP)・cm/cm ²・sec・cmHg.

Claims (1)

[Scope of Claims] 1 Repeating unit represented by the structural formula [Formula] and general formula [Formula] (wherein R ¹ has 1 to 2 carbon atoms, which may be substituted with a hydrogen atom, a halogen atom, or a halogen atom)
^R2 is a perfluoroalkyl group having 1 to 3 carbon atoms, a trialkylsilyl group having 3 to 9 total carbon atoms, an alkyl group having 1 to 10 carbon atoms substituted with a phenyl group or a halogen-substituted phenyl group, phenyl group, halogen-substituted phenyl group, carbon number 1-
10 alkyl groups or ^{a group represented} by formula represents an alkyl group having 1 to 2 carbon atoms substituted with a perfluoroalkyl group having 1 to 6 carbon atoms, a phenyl group, or a halogen-substituted phenyl group. ) A random copolymer formed from repeating units represented by the formula, having a molar ratio of monomer units in the range of 95/5 to 40/60, and a molecular weight of 10,000 or more.