JPS60208308A - Oxygen-enriching membrane - Google Patents

Abstract

PURPOSE:An oxygen-enriching membrane that is made of a polymer from a compound with a specific structure containing silyl groups, thus having large coefficient of oxygen separation from a nitrogen and a large permeability, and giving thin films of high mechanical strength. CONSTITUTION:A compound of formula I (n is 1 or 2) is polymerized in a solvent such as toluene using a catalyst such as TaCl5 at 30-130 deg.C to give a polymer of formula II. The polymer is precipitated in an appropriate solvent such as methanol, purified, dissolved in benzene, casted into a thin film to give the objective oxygen-enriching membrane.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oxygen enrichment membrane used to increase the oxygen concentration of air or the like.

The material for the oxygen enrichment membrane is required to have the following three properties.

(1) The separation coefficient between oxygen and nitrogen is large, at least 3 or more than 1.
−.

Such a separation factor is absolutely necessary in order to obtain a gas containing more than 60% oxygen from air.

Such a separation factor is absolutely necessary.

(2) High oxygen permeability coefficient, at least 10-9 cm
'(STP) cm/crrf m see * c
+ Must have Hg.

Although the permeation rate can be increased by making the membrane thinner, the above-mentioned oxygen coefficient is required for the oxygen-enriching membrane.

(3) It must have sufficient mechanical strength even when made into a thin film.

However, the copolymers of polysiloxane or polycarbonate and siloxane conventionally known for this purpose are
Although the oxygen permeability coefficient is high, the separation coefficient is small at about 2.0, and the mechanical strength when formed into a thin film is low. Po17merPreprints 32 (
10), 2981, polytrimethylsilylmethylacetylene has high strength when formed into a thin film and has a large oxygen permeability coefficient, but its partition coefficient is approximately 1.
．． On the other hand, polytrimethylvinylsilane has a high separation coefficient of 4.5 and an oxygen permeability coefficient of 4.5.
Xl0-9crn" (STP) C layer/crn'・5
Although the ecac film is reasonably good as Hg, it has the disadvantage that it is difficult to produce a polymer with high film strength and it is impossible to form a thin film.

SUMMARY OF THE INVENTION An object of the present invention is to provide an oxygen-enriched membrane that has both a large oxygen-nitrogen separation coefficient and an oxygen permeability coefficient and can be manufactured as a thin film with high mechanical strength.

The present invention provides an oxygen-enriched membrane made of a polymer obtained by polymerizing a compound represented by the general formula (I): (wherein n represents an integer of 1 or 2).

The present invention has completely improved the drawbacks of conventional oxygen enrichment membranes. The oxygen enrichment membrane of the present invention has an oxygen and nitrogen separation coefficient of 3.0 or more, and an oxygen permeability coefficient of 8X 1O-
9crn” (STP) Cm/crn' ++ s
ee*cmHg or more. Furthermore, the tensile strength is 3
00 kg/crn' or more, which can be easily formed as a stretchable film and which exhibits sufficient strength even when made into a thin film, is a polymer that can be easily formed into a stretchable film and has sufficient strength even when made into a thin film. Tac15, Mbc15 in organic solvents such as alized methylene.

↑ac15-Ph4 Sn, Tac15-Ph3
It is produced by polymerization at a temperature of 30 to 130°C under a catalyst such as Bi. The polymer is usually precipitated in a suitable solvent such as methanol, purified, and then used to form an oxygen-enriched membrane.

4-The polymer generally has a structure represented by the formula % (% formula % ) (wherein n is as described above) and has a weight average molecular weight of 5 x 104
~5X108 (preferably 3X105 to 5x106)
Although it is necessary to increase the film strength by -1, it can be easily obtained by the above polymerization.

1-, the polymers listed are hydrocarbons such as benzene, toluene, and hexane, chloroform, and 41! ! It can be dissolved in halogenated hydrocarbons such as carbon dioxide, tetrahydrofuran, etc., and processed into excellent thin films or hollow fibers by casting, dry or wet spinning, or other methods. Since this material has the above-mentioned physical properties, it is used as an ideal oxygen enrichment membrane.

Furthermore, an anisotropic film can be formed and used by adding a poor solvent such as ethyl alcohol or isobutamel to the solution described above.

Hereinafter, the present invention will be specifically explained with reference to Examples.
20 mg was dissolved, and then 18.4 g of l-methyl-2-D-limethylsilylmethyldimethylsilyl)acetylene was added, and polymerization was carried out at 80° C. for 24 hours. The resulting polymer was diluted with 500 su of toluene, poured into excess methanol to precipitate, filtered, washed repeatedly with methanol, and dried. 100%).

This polymer was dissolved in tetrahydrofuran and ape
(Column: A-80M manufactured by Showa Denko KK) to determine the molecular weight, and the weight average molecular weight in terms of polystyrene was 1.5 x 106.

Next, a tensile test was conducted on the 4B thick film obtained by casting according to the method of JIS K-7111-77, and the tensile strength was 415Kg.
/crn', and when the air permeation rate was measured by the low pressure method, the oxygen permeation coefficient P02 was 8.1×10
= (am' (STP) cs+/crn' *
sec * ci + Hg) 't' An, nitrogen permeability coefficient PN2 is 2.3 x 1O-9 (cm' (STP)
c+i/crrr' e sec * cmHg), and the separation coefficient between oxygen and nitrogen was 3.6.

Polymerization catalyst Tacls -Ph4 to missing Etolue 7!005M
1.4 g of Sn was dissolved, and then 8 g of 1-methyl-2-(2-()limethylsilyl)ethyldimethylsilyl]acetylene:IL was added, and the mixture was reacted at 80° C. for 24 hours. The resulting polymer was diluted with 500 mM toluene, poured into excess methanol to precipitate it, filtered, washed repeatedly with methanol, and dried. Formula: % Formula %: Polymer 11.5. (yield 58%).

In the same manner as in Example 1, the weight average molecular weight of this polymer was determined to be 4.0 Xl05.Next, the tensile strength was determined in the same manner as in Example 1 for a film having a thickness of 8 l obtained by casting. When I looked at it, it was 32.
It was 0 kg/crn'. Furthermore, when the air permeation rate of this film was measured in the same manner as in Example 1, the oxygen permeability coefficient 202 was 5.5 x 10-'(crri" (
STP ) cm/crn' e see * cmH
g], and the nitrogen permeability coefficient is 1.4 x lo-9
(cm'(STP)C/crn'·5ecec intestinal Hg), and the separation coefficient between oxygen and nitrogen was 3.9.

χDirect] Using the 1-methyl-2-(trimethylsilylmethyldimesylsilyl)acetylene polymer of Example 1, a film with a thickness of 2.2 μm was produced by casting. The tensile strength of this material was measured in the same manner as in Example 1, and it was found to be 410 kg/crn', which was a strong strength.The absolute permeation rate of air was then measured by the low pressure method, and the permeation rate of #element RO2 was 3.8 x 10-”'
(crn' (STP /ctn' e xec *
amHg), and the nitrogen permeation rate RN2 is 1. I
Xl0-5(cm'(STP/crn' ++ s
ec*cmHg), and the separation coefficient between oxygen and nitrogen was 3.5.

Thus, this polymer had sufficient strength even when made into a very thin membrane, and had good performance as an oxygen enrichment membrane.

Patent issuer: Shin-Etsu Chemical T-gyo Co., Ltd., agent, patent attorney: Shushi Iwamiya (TE letter stamped) May 11, 1980 Commissioner of the Japan Patent Office Kazuo Wakasugi1, 61 items displayed Patent application No. 1988 085471
No. 3 No. 2, Name of the invention Oxygen-enriching membrane 3, Person making the amendment Name Representative Yutabe Koita 4, Agent 8 Contents of the amendment Detailed explanation of the invention by Jll Sora as follows: Supplement 11: Yes.

(1) Delete "Such a separation coefficient is absolutely necessary." from the first and last lines.

(2) In the third and subsequent lines, [...to show strength] was corrected to r...0, which indicates the advantage of being able to show a strong side, and 1 used in the present invention. do.

(3) rTac15, Nbc1 in lines 3 to 4 of page m4
5, Tac15-Ph4 Sn, Tac15-P
h3 BiJ, rTac15, NbCl5,
TaCl5-Ph4 Sn, TaCl5-Ph3
BiJ corrected.

(4) 6 lines from the bottom of the 5th line “1’s 100-m sentence” r1
00+nJL, I and revised iE l, , rTac15
” is corrected to “Fly TaCl5 J”.

(5) The following formula % formula % in 3 lines t1 from the bottom of page w45 Correct it accordingly: j.

(6) Change r3.8 J on page 7, line 3 to r3.5 J
Revised 112.

(7) rTac on page 7, line 5
Correct it as ls J.

(8) Page 8, line 6 from the bottom]-1, [...methyldimethylsilyl)acetylene polymer J], ``...methyldimethylsilyl)acetylene polymer 1
I am corrected.

(9) r (cm' (STP / crn' 6 sec *
cmHg) J, r (cm' (STP)/cr
Correct it as rr' Φsec * cmHg) j.

Claims (1)

[Claims] 1. An oxygen enrichment membrane made of a polymer obtained by polymerizing a compound represented by the general formula: (wherein n represents an integer of 1 or 2).