JP5489028B2 - Polyurethane resin-forming composition and sealing material - Google Patents

Description

  The present invention relates to a polyurethane resin-forming composition and a sealing material using the composition.

  In recent years, hollow fiber membrane modules using hollow fibers as separation membranes are widely used in industrial fields such as water treatment membranes and medical fields such as blood treatment. Especially for applications such as water purifiers, artificial kidneys, and artificial lungs, the demand is extremely increasing. As such a hollow fiber membrane module, it is widely used a polyurethane resin excellent in flexibility, adhesiveness and chemical resistance at normal temperature as a sealing material for bonding and fixing the end portion where the hollow fiber membranes are converged. Are known.

  Generally, hollow fibers used in hollow fiber membrane modules are made of glycerin-containing hollow fibers in which a retaining agent (glycerin) is used to maintain pores, and synthetic polymers as raw materials. There are non-containing glycerin-free hollow fibers. However, in the glycerin-containing hollow fiber, when a polyurethane resin-forming composition containing diphenylmethane diisocyanate (hereinafter abbreviated as MDI) is used during casting, a low-molecular reaction product of MDI and glycerin is generated. It is known that the reaction product dissolves into the blood and adversely affects the human body. For this reason, for the purpose of lowering the elution of the low-molecular-weight reaction product, toluene diisocyanate (hereinafter abbreviated as TDI) or hexamethylene diisocyanate (hereinafter abbreviated as HDI) is introduced, and polyurethane utilizing the difference in reactivity with MDI is used. Resin system is used. For example, in Japanese Patent Laid-Open No. 6-25383 (Patent Document 1), an attempt is made to lower the viscosity by using a blocked product of a castor oil fatty acid lower alkyl ester of an isocyanate compound, and for the purpose of lowering the elution of the low molecular reactant. A cast polyurethane resin-forming composition incorporating TDI is described.

  In recent years, products having a high filling rate of hollow fibers have been developed, and the potting material is required to have a low viscosity from the viewpoint of resin permeability. In the glycerin-free hollow fiber, since a reaction product of MDI and glycerin is not generated, the design of a low viscosity system is relatively easy. However, since the potting material system is different between the glycerin-containing hollow fiber and the glycerin-free hollow fiber, in the membrane module using the glycerin-containing hollow fiber, in addition to the method of introducing the TDI or the HDI In addition, there has been no MDI system that can achieve both low elution of the low-molecular-weight reactant and reduction of the mixing viscosity.

  As a method for obtaining a sealing material, for example, in Japanese Patent Application Laid-Open No. 7-213871 (Patent Document 2), an isocyanate group-terminated prepolymer obtained from a reaction product of polymethylene polyphenyl polyisocyanate and MDI and castor oil is used as an isocyanate component. A polyurethane resin obtained by curing a polymer with a polyol has been proposed. However, in the polyurethane resin described in Patent Document 2, although MDI is reacted with castor oil and polymethylene polyphenyl polyisocyanate is added to lower the viscosity, the viscosity of the main agent is high. And the curing viscosity of the curing agent is high. In recent years, the filling rate of hollow fibers has been further increased, and from the viewpoint of permeability to details, the polyurethane resin described in Patent Document 2 is concerned about poor filling during molding.

JP-A-6-25383 JP 7-213871 A

  The present invention has been made in view of the above problems, and a polyurethane resin-forming composition capable of achieving both low elution of a reaction product of MDI and glycerin and reduction in mixed viscosity and the composition. It is in providing the sealing material using this.

  As a result of intensive studies to solve the above problems, the present inventors have made a polyurethane resin-forming composition comprising a main agent (A) containing an isocyanate component and a curing agent (B) containing a polyol component. In the above, it was found that the above-mentioned problems can be solved by incorporating a specific isocyanate component into the main agent (A).

That is, the present invention
(1) A polyurethane resin-forming composition for a hollow fiber membrane module sealing material comprising a main component (A) containing an isocyanate component and a curing agent (B) containing a polyol component,
As an isocyanate component constituting the main agent (A),
Obtained by reacting polyisocyanate (hereinafter referred to as pomeric MDI) (a1), which is a mixture of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate, with aliphatic alcohol (a2) having 10 to 15 carbon atoms, and isocyanate An isocyanate group-terminated prepolymer having a group (NCO) content of 15.0 to 21.5% by mass,
As a polyol component constituting the curing agent (B),
At least one (b1) selected from the group consisting of castor oil and castor oil-based modified polyol, and a hydroxyl group-containing amine compound (b2),
Polyurethane resin-forming composition.

  (2) The polyurethane resin-forming composition according to (1), wherein the aliphatic alcohol (a2) has a side chain.

  (3) In the polymeric MDI (a1), the mass ratio of the diphenylmethane diisocyanate and the polymethylene polyphenyl polyisocyanate (the mass of diphenylmethane diisocyanate / the mass of polymethylene polyphenyl polyisocyanate) is 20/80 to 80/20. The polyurethane resin-forming composition according to (1) or (2).

  (4) The hydroxyl group-containing amine compound (b2) according to any one of (1) to (3), wherein the hydroxyl group-containing amine compound (b2) is N, N, N ′, N′-tetrakis [2-hydroxypropyl] ethylenediamine. Polyurethane resin-forming composition.

  (5) A sealing material obtained by curing the polyurethane resin-forming composition according to any one of (1) to (4).

  (6) A hollow fiber membrane module comprising the sealing material according to (5).

  According to the present invention, it is possible to provide a polyurethane resin-forming composition capable of achieving both a low elution of a reaction product of MDI and glycerin and a reduction in mixed viscosity, and a sealing material using the composition.

  In the present invention, a polyurethane resin-forming composition having an elution amount of a reaction product of MDI and glycerin (low molecular eluate value) and a low viscosity and good filling property when a membrane module is produced is obtained. I can do it. Further, by using the polyurethane resin-forming composition of the present invention, it becomes possible to provide a sealing material useful as a sealing material for a hollow fiber membrane module or the like without considering the presence or absence of glycerin contained in the hollow fiber.

  The present invention is described in further detail below.

  First, the polyurethane resin-forming composition of the present invention will be described. The polyurethane resin-forming composition of the present invention comprises a main agent (A) containing an isocyanate component and a curing agent (B) containing a polyol component.

<Main agent (A)>
The main agent (A) according to the present invention is obtained by reacting polymeric MDI (a1) with an aliphatic alcohol (a2) having 10 to 15 carbon atoms as an isocyanate component, and has an isocyanate group (NCO) content. Contains an isocyanate group-terminated prepolymer of 15.0 to 21.5% by mass.

(Polymeric MDI (a1))
The polymeric MDI (a1) according to the present invention is a mixture of diphenylmethane diisocyanate (MDI) (a1-1) and polymethylene polyphenyl polyisocyanate (a1-2). The MDI (a1-1) has two isocyanate groups and two benzene rings, and is called a so-called dinuclear body. The polymethylene polyphenylene polyisocyanate (a1-2) has three or more isocyanate groups and benzene rings, and is called a so-called polynuclear body.

  The mass ratio of the MDI (a1-1) to the polymethylene polyphenyl polyisocyanate (a1-2) (mass of (a1-1) / mass of (a1-2)) is 20/80 to 80 / 20 is preferable, and 30/70 to 45/55 is more preferable. When the ratio of (a1-1) is less than the lower limit, filling failure tends to occur due to an increase in viscosity. On the other hand, when the said upper limit is exceeded, the low temperature storage stability of the main ingredient (A) obtained will fall, and it exists in the tendency for a low molecular eluate value to increase.

  The MDI (a1-1) has three types of isomers: 2,2′-MDI, 2,4′-MDI, and 4,4′-MDI. The composition ratio of the isomers in the MDI (a1-1) is such that the total content of 2,2′-MDI and 2,4′-MDI is 20 masses based on the total mass of the MDI (a1-1). % Or less, more preferably 10% by mass or less. When the total content of 2,2′-MDI and 2,4′-MDI exceeds the upper limit, the reactivity of the resulting polyurethane resin-forming composition is reduced, and the cured resin and one type of seal are included. There is concern about a decrease in the hardness of the material.

(Fatty alcohol (a2))
The aliphatic alcohol (a2) according to the present invention needs to have 10 to 15 carbon atoms (decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, myristyl alcohol, pentadecyl alcohol), and further has a carbon number. Is preferably 12-14. When the number of carbon atoms is less than the lower limit, the viscosity of the isocyanate group-terminated prepolymer is increased, so that problems such as poor packing properties at the time of molding the membrane module and peeling at the time of cutting in the resulting cured resin occur. On the other hand, when the number of carbons exceeds the above upper limit, in the case of a linear aliphatic alcohol, there is a problem that heating is required during production due to solidification, or a low molecular eluate value is increased. In addition, as the aliphatic alcohol (a2), in a methanol extraction test imposed on medical plastic products, when linear alcohol is used, the structure is similar and the methanol extraction rate becomes high. Therefore, it preferably has a side chain.

  The isocyanate group-terminated prepolymer according to the present invention is obtained by reacting the polymeric MDI (a1) with the aliphatic alcohol (a2). As reaction for obtaining the said isocyanate group terminal prepolymer, the urethanation reaction normally performed can be employ | adopted suitably.

  The isocyanate group content of the isocyanate group-terminated prepolymer according to the present invention is 15.0 to 21.5% by mass, preferably 16.0 to 20.0% by mass, and more preferably 16.0 to 18.0%. % By mass. By using an isocyanate group-terminated prepolymer having an isocyanate group content within the above range, a polyurethane that is particularly excellent in molding processability when forming a sealing material, particularly when the sealing material is used for producing a hollow fiber membrane module. A resin-forming composition can be obtained, and a hollow fiber membrane module can be produced without causing molding defects.

  In addition, as the main agent (A) according to the present invention, if necessary, an isocyanate compound other than the polymeric MDI (a1) and an isocyanate compound other than the polymeric MDI (a1) may be used as long as the effects of the present invention are not impaired. And an aliphatic alcohol (a2) may be further included as an isocyanate component. Examples of isocyanate compounds other than the polymeric MDI (a1) include TDI, xylene diisocyanate, nitrodiphenyl diisocyanate, diphenylpropane diisocyanate, dimethyldiphenylmethane diisocyanate, phenylene diisocyanate, naphthylene diisocyanate, dimethoxydiphenyl diisocyanate, tetramethylene diisocyanate, HDI, and methyl. Isocyanates such as pentane diisocyanate, lysine diisocyanate, isophorone diisocyanate, hydrogenated TDI, hydrogenated xylene diisocyanate, hydrogenated MDI, tetramethylxylene diisocyanate; polymeric, urethane-modified, urea-modified, allophanate-modified, biuret of these isocyanates Degeneration , Carbodiimide-modified products, uretonimine modified product, uretdione modified product, an isocyanurate modified product, and the like, may be even one of these or two or more kinds.

<Curing agent (B)>
The curing agent (B) according to the present invention contains, as a polyol component, at least one (b1) selected from the group consisting of castor oil and castor oil-based modified polyol, and a hydroxyl group-containing amine compound (b2). .

(Castor oil, castor oil-based modified polyol (b1))
The castor oil and castor oil-based modified polyol (b1) according to the present invention is obtained by the reaction of castor oil, castor oil fatty acid and polyol (at least one selected from the group consisting of low molecular polyols and polyether polyols). Examples of the polyester include, for example, castor oil fatty acid diglyceride and monoglyceride; castor oil fatty acid and trimethylol alkane mono-, di- and triester; castor oil fatty acid and polypropylene glycol Mono, di, triester and the like can be mentioned.

  Here, the main component of the castor oil is triglyceride of ricinoleic acid. In the present invention, the castor oil includes hydrogenated castor oil. The main component of the castor oil fatty acid is ricinoleic acid. In the present invention, the castor oil fatty acid includes hydrogenated castor oil fatty acid.

  Examples of the trimethylol alkane include trimethylol methane, trimethylol ethane, trimethylol propane, trimethylol butane, trimethylol pentane, trimethylol hexane, trimethylol heptane, trimethylol octane, trimethylol nonane, trimethylol decane. Is mentioned.

  The number average molecular weight of the castor oil and castor oil-based modified polyol (b1) according to the present invention is preferably 400 to 3000, and more preferably 500 to 2500. According to the polyurethane resin-forming composition obtained by using at least one (b1) selected from the group consisting of castor oil and castor oil-based modified polyol having a number average molecular weight within the above range, the sealing material is required. The cured resin having good physical properties (particularly mechanical properties) can be formed.

  The average hydroxyl value of the castor oil and castor oil-based modified polyol (b1) according to the present invention is preferably 20 to 300 mgKOH / g, more preferably 40 to 250 mgKOH / g. According to the polyurethane resin-forming composition obtained by using at least one (b1) selected from the group consisting of castor oil and castor oil-based modified polyol having an average hydroxyl value within the above range, the sealing material is required. The cured resin having good physical properties (particularly mechanical properties) can be formed, and the productivity of the sealing material, and hence the productivity of the hollow fiber membrane module (filter device) can be improved.

(Hydroxyl-containing amine compound (b2))
Examples of the hydroxyl group-containing amine compound (b2) according to the present invention include low molecular polyamines and low molecular amino alcohols (for example, ethylenediamine which is an oxyalkylated derivative of an amino compound, etc. (N, N, N ′, N′-tetrakis [ 2-hydroxypropyl] ethylenediamine, N, N, N ′, N′-tetrakis [2-hydroxyethyl] ethylenediamine, etc.) propylene oxide or ethylene oxide adduct; mono-, di-, triethanolamine; N-methyl-N, And amine compounds such as N′-diethanolamine). Among these, propylene oxide or ethylene oxide adduct such as ethylenediamine is preferable, and N, N, N ′, N′-tetrakis [2-hydroxypropyl] ethylenediamine is most preferable. By using N, N, N ′, N′-tetrakis [2-hydroxypropyl] ethylenediamine, the processability at the time of molding is further improved, and the low molecular eluate value tends to be further decreased.

  Containing at least one (b1) selected from the group consisting of castor oil and castor oil-based modified polyol and the hydroxyl group-containing amine compound (b2) as a polyol component constituting the curing agent (B) according to the present invention The cured resin formed by the polyurethane resin-forming composition of the present invention and the sealing material which is one type thereof are particularly excellent in moldability, adhesiveness and heat resistance.

  As the curing agent (B) according to the present invention, a mass ratio ((1) selected from the group consisting of castor oil and castor oil-modified polyol (b1) and the hydroxyl group-containing amine compound (b2) (( b1) / (b2)) is preferably 85/15 to 75/25, more preferably 83/17 to 77/23. When the ratio of the hydroxyl group-containing amine compound (b2) is less than the lower limit, the reactivity of the polyurethane resin-forming composition is deteriorated, and the resulting cured resin and the hardness of the sealing material that is one type thereof are low. On the other hand, when the above upper limit is exceeded, the reactivity of the polyurethane resin-forming composition becomes too high, the workability is deteriorated, and the filling property is impaired or obtained. There is a tendency that the hardness of the cured resin and one kind of sealing material thereof becomes too high.

(Active hydrogen group-containing compound)
In the present invention, in the curing agent (B), at least one selected from the group consisting of castor oil and castor oil-based modified polyol (b1) and active hydrogen other than the hydroxyl group-containing amine compound (b2) A group-containing compound (hereinafter referred to as “active hydrogen group-containing compound (b3)”) may further be contained.

  Examples of the active hydrogen group-containing compound (b3) include polyols such as low-molecular polyols, polyether-based polyols, polyester-based polyols, polylactone-based polyols, and polyolefin-based polyols. These may be used alone or in combination of two or more. Can be used in combination.

  Examples of the low molecular polyol include ethylene glycol, diethylene glycol, propylene glycol, 1,2- / 1,3- / 1,4-butanediol, 1,5-pentanediol, and 3-methyl-1,5-pentane. Divalent polyol (low molecular glycol) such as diol, 1,6-hexane glycol, 1,8-octanediol, 1,10-decanediol, neopentyl glycol, hydrogenated bisphenol A; glycerin, trimethylolpropane, hexane Examples thereof include tri to octavalent polyols such as triol, pentaerythritol, sorbitol, and shoelace. The molecular weight of such a low molecular polyol is usually 50 to 200.

  The polyether-based polyol is a polymerization obtained by using the above low-molecular-weight polyol as an initiator and adding an alkylene oxide (for example, an alkylene oxide having 2 to 8 carbon atoms such as ethylene oxide, propylene oxide, butylene oxide). Specific examples include polypropylene glycol, polyethylene glycol, PTMG, and chipped ether that is a copolymer of ethylene oxide and propylene oxide. The molecular weight of such a polyether polyol is usually 200 to 7000, preferably 500 to 5000. By using a polyether-based polyol having a molecular weight within the above range, a polyurethane resin-forming composition particularly excellent in molding processability when forming a sealing material, particularly when the sealing material is used for producing a hollow fiber membrane module A thing is obtained.

  Examples of the polyester polyol include polycarboxylic acids (saturated or unsaturated aliphatic polycarboxylic acids such as azelaic acid, dodecanoic acid, maleic acid, fumaric acid, itaconic acid, ricinoleic acid and dimerized linoleic acid; phthalic acid, isophthalic acid Examples thereof include polyols obtained by condensation polymerization of an acid, an aromatic polycarboxylic acid such as terephthalic acid) and a polyol (the low molecular polyol and the polyether polyol).

  The molecular weight of such a polyester-based polyol is usually 200 to 5000, preferably 500 to 3000. By using a polyester-based polyol having a molecular weight within the above range, a polyurethane resin-forming composition that is particularly excellent in molding processability when forming a sealing material, particularly when the sealing material is used for producing a hollow fiber membrane module Is obtained.

  Examples of the polylactone-based polyol include polymerization initiators such as glycols and triols, ε-caprolactone, α-methyl-ε-caprolactone, ε-methyl-ε-caprolactone, and β-methyl-δ-valerolactone. And polyols obtained by addition polymerization in the presence of a catalyst such as an organometallic compound, a metal chelate compound, or a fatty acid metal acyl compound.

  The molecular weight of such a polylactone-based polyol is usually 200 to 5000, and preferably 500 to 3000. By using a polylactone-based polyol having a molecular weight within the above range, a polyurethane resin-forming composition that is particularly excellent in molding processability when forming a sealing material, particularly when the sealing material is used for producing a hollow fiber membrane module Is obtained.

  Examples of the polyolefin-based polyol include polybutadiene and a polybutadiene-based polyol in which a hydroxyl group is introduced at the terminal of a copolymer of butadiene and styrene or acrylonitrile.

  In addition, the polyether ester polyol obtained by addition-reacting an alkylene oxide (for example, ethylene oxide, propylene oxide, etc.) to a polyester having at least one of a carboxyl group and an OH group at the terminal is also the active hydrogen group-containing compound. It can be used as (b3).

  Mass ratio ((b1) of the active hydrogen group-containing compound (b3) to at least one selected from the group consisting of the castor oil and castor oil-modified polyol in the curing agent (B) according to the present invention. ): The mass of (b3)) is preferably 50:50 to 100: 0, particularly preferably 100: 0. When the components of the curing agent (B) are (b1), (b2), and (b3), the ratio is: {(mass of (b1)) + (mass of (b3)) } / (Mass of (b2)) is preferably 85/15 to 75/25, and from the viewpoint of excellent curability and fillability of the polyurethane resin-forming composition, 83/17 More preferably, it is -77/23.

<Polyurethane resin-forming composition>
In the polyurethane resin-forming composition of the present invention, the mixing ratio of the main agent (A) and the curing agent (B) is an isocyanate group in the isocyanate component constituting the main agent (A), and the curing agent (B Polyol component (at least one selected from the group consisting of castor oil and castor oil-based modified polyol (b1), a hydroxyl group-containing amine compound (b2) and an optional active hydrogen group-containing compound (b3)) It is preferable that the molar ratio (number of moles of isocyanate group / number of moles of active hydrogen group) with the active hydrogen group in the ratio is 0.8 to 1.6, more preferably 0.9 to 1. .2 and particularly preferably 1.0 to 1.1. According to the polyurethane resin-forming composition obtained in such a mixing ratio, it is possible to form a cured resin excellent in durability and a very small amount of low-molecular eluate in water and a sealing material that is one type thereof. it can.

  The polyurethane resin-forming composition of the present invention may further contain a known urethanization catalyst. Examples of the urethanization catalyst include metal compound catalysts such as organotin compounds; triethylenediamine (TEDA), tetramethylhexamethylenediamine (TMHMDA), pentamethyldiethylenetriamine (PMDETA), dimethylcyclohexylamine (DMCHA), bisdimethylaminoethyl. And tertiary amine catalysts such as ether (BDMAEA).

  In the polyurethane resin-forming composition of the present invention, the mixing viscosity of the main agent (A) and the curing agent (B) is sufficiently low, and according to the polyurethane resin-forming composition of the present invention, MDI and A cured resin having a sufficiently small elution amount of the reaction product with glycerin (low molecular eluate value) and a sealing material that is one type thereof can be obtained.

  Next, the sealing material of the present invention will be described. The sealing material of the present invention comprises a cured resin obtained by curing the polyurethane resin-forming composition of the present invention.

  Specifically, the polyurethane resin-forming composition of the present invention comprising the main agent (A) and the curing agent (B) is prepared at room temperature, and is 0 ° C to 100 ° C, preferably 30 ° C to 80 ° C. More preferably, it is suitably formed by reacting and curing the isocyanate component constituting the main agent (A) and the polyol component constituting the curing agent (B) under a temperature condition of 30 ° C. to 60 ° C. Can do. For the purpose of shortening the gel time and reducing the viscosity of the composition, each of the main agent (A) and the curing agent (B) is added to 30 to 60 ° C. before mixing as necessary. You may use it warm.

Next, the hollow fiber membrane module of the present invention will be described. The hollow fiber membrane module of the present invention includes the sealing material of the present invention. In such a hollow fiber membrane module, the gaps between the hollow fiber membranes at the ends of a plurality of hollow fiber membrane bundles are sealed with the polyurethane resin-forming composition of the present invention, and the composition is cured to thereby form the present invention. Can be manufactured by forming the sealing material (by this, the gap between the hollow fiber membranes is sealed by the sealing material) and housing the focusing body in the housing.
As a specific structure of the hollow fiber membrane module (hollow fiber membrane filtration device) of the present invention, a known structure can be adopted as appropriate, for example, a structure described in JP-A-11-5023. Yes, but not limited to this.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not construed as being limited to these examples.

[Production Example 1: Production of main agent (A-1)]
The inside of a 2 L four-necked flask equipped with a thermometer, a stirrer, a nitrogen seal tube, and a cooling tube was purged with nitrogen. Into this flask, 735 g of the following isocyanate 1 was charged, and the temperature increase and stirring of the isocyanate 1 was started. When the temperature of the isocyanate 1 reaches 50 ° C., 265 g of the following aliphatic alcohol 1 is added, and the mixture is reacted by stirring and mixing at 70 ° C. for 3 hours in a nitrogen atmosphere to constitute the main component (A). A base end prepolymer was obtained. Hereinafter, this is referred to as “main agent (A-1)”. In main agent (A-1), the isocyanate group (NCO) content in the obtained isocyanate group-terminated prepolymer was 17.5% by mass, and the viscosity at 25 ° C. was 2860 mPa · s.

[Production Examples 2 to 8: Production of main agents (A-2) to (A-8)]
Main agents (A-2) to (A-8) were obtained in the same manner as in Production Example 1 except that the composition of the raw material was changed to the composition shown in Table 3. The isocyanate 1 and aliphatic alcohols 1-3 used as raw materials are as follows. Table 3 shows the NCO content and viscosity of the obtained isocyanate group-terminated prepolymer in each of the obtained main agents.

[Preparation Example 1: Preparation of curing agent (B-1)]
81.0 parts by mass of the following polyol 1 and 19.0 parts by mass of the following polyol 2 were uniformly mixed to prepare a curing agent (B). Hereinafter, this is referred to as “curing agent (B-1)”.

Isocyanate 1: “Millionate MR-200 (trade name)” (manufactured by Nippon Polyurethane Industry Co., Ltd.) NCO content = 31.6 mass%, polymethylene polyphenyl polyisocyanate content 56 mass%, MDI content 44 mass% (2,2′-MDI and 2,4′-MDI content 3 mass%),
Aliphatic alcohol 1: “Tridecanol (trade name)” (manufactured by Kyowa Hakko Chemical Co., Ltd.), hydroxyl value = 280 KOHmg / g, carbon number 13,
Aliphatic alcohol 2: “Octanol (trade name)” (manufactured by Kyowa Hakko Chemical Co., Ltd.), hydroxyl value = 431 KOH mg / g, carbon number 8,
Aliphatic alcohol 3: “isostearyl alcohol (trade name)” (manufactured by Higher Alcohol Industry Co., Ltd.), hydroxyl value = 206 KOHmg / g, carbon number 18,
Polyol 1: Castor oil “URIC H-30 (trade name)” (manufactured by Ito Oil Co., Ltd.), nominal average functional group number = 2.7, hydroxyl value = 160 KOH mg / g, number average molecular weight: 1000,
Polyol 2: N, N, N ′, N′-tetrakis [2-hydroxypropyl] ethylenediamine, nominal average functional group number = 4.0, hydroxyl value = 760 mgKOH / g,
Here, the nominal average functional group number refers to the value described in the catalog or the like by the manufacturer of the aliphatic alcohol and polyol, or the functional group number of the initiator used when obtaining the aliphatic alcohol and polyol.

Example 1
[Low molecular eluate value measurement sample]
First, the main agent (A-1) (liquid temperature 50 ° C.) and the curing agent (B-1) (liquid temperature 50 ° C.) are mass ratio (mass of (A-1) / mass of (B-1)). The mixture was mixed so that the total mass became 80 g and manually stirred for 15 seconds using a spatula. Next, 40 g of glycerin was added to the mixed solution and further stirred for 15 seconds to obtain a polyurethane resin-forming composition. This polyurethane resin-forming composition (100 g) was cast into a cartridge case (made of polycarbonate with an inner diameter of 48 mm) in a centrifugal molding machine and subjected to centrifugal molding to obtain a cured resin (low molecular eluate value measurement sample). Centrifugal molding conditions were as follows: the primary curing condition was 1500 rpm at a centrifugal molding machine, the temperature was 50 ° C., and the time was 10 minutes, and the secondary curing condition was left in the thermostatic layer at a temperature of 45 ° C. and a time of 2 days.

[Hardness measurement sample]
First, the main agent (A-1) (liquid temperature 50 ° C.) and the curing agent (B-1) (liquid temperature 50 ° C.) are mass ratio (mass of (A-1) / mass of (B-1)). Is 54/46, and the mixed liquid so that the total mass becomes 100 g is manually stirred using a spatula for 30 seconds, and then subjected to degassing under reduced pressure (10 to 20 kPa for 1 minute) to form a polyurethane resin-forming composition I got a thing. Next, this polyurethane resin-forming composition (75 g) was charged into a polypropylene cup, and this was left to cure at 45 ° C. for 2 days, and then demolded to obtain a cured resin (hardness measurement sample).

(Examples 2-4, Comparative Examples 1-4)
Instead of the main agent (A-1), the main agents (A-2) to (A-8) obtained in Production Examples 2 to 8 described in Tables 1 and 2 were used, respectively, and the mass ratio of the main agent and the curing agent was determined. Resin cured products (low molecular eluate value measurement sample and hardness measurement sample) were obtained in the same manner as in Example 1 except that the mass ratios described in Tables 1 and 2 were used.

<Viscosity measurement>
The viscosity of the main agent obtained in each Production Example (Production Examples 1 to 8) was measured using a B-type rotational viscometer at a liquid temperature of 25 ° C. of the main agent.

<Mixed viscosity measurement>
The mixed viscosity of the polyurethane resin-forming composition in each example and comparative example (Examples 1-4 and Comparative Examples 1-4) was measured by the following method. First, the main agent (A-1) (liquid temperature 50 ° C.) and the curing agent (B-1) (liquid temperature 50 ° C.) are mass ratio (mass of (A-1) / mass of (B-1)). Was a mass ratio of each Example and Comparative Example, and the mixed solution mixed so that the total mass became 120 g was manually stirred for 30 seconds using a spatula to obtain each polyurethane resin-forming composition. Next, 100 g of the obtained polyurethane resin-forming composition was charged into a polypropylene cup, and the polyurethane resin-forming composition 60 seconds after mixing using a B-type rotational viscometer in an atmosphere at 25 ° C. The viscosity of this was measured, and this was taken as the mixed viscosity.

<Low molecular eluate extraction test>
The low molecular eluate value of the resin cured product obtained in each Example and Comparative Example (Examples 1 to 4, Comparative Examples 1 to 4) was measured by the following method. First, 20 g of the low molecular eluate value measurement samples obtained in each Example and Comparative Example were cut into a fan shape and weighed, 100 ml of purified water was added, and the mixture was shaken at 40 ° C. for 2 hours (using a shaker). The low molecular eluate was extracted into purified water. Next, the obtained extract was decanted and 10 ml was placed in a 50 ml volumetric flask, and the liquid adjusted to 50 ml by adding purified water was used as a test solution, and UV absorbance measurement (Shimadzu Corporation UV-1500) was performed. The maximum value of absorbance at 240 to 245 nm / 10 was defined as the low molecular eluate value.

<Hardness measurement test>
The hardness of the cured resin obtained in each of Examples and Comparative Examples (Examples 1 to 4 and Comparative Examples 1 to 4) was measured by the following method. About the hardness measurement sample obtained by each Example and the comparative example, by the method based on the method of JIS-K7312 after JIS-D hardness 10 seconds after a measurement instant and a measurement instant on 25 degreeC temperature conditions. It was measured.

<MDI content measurement test>
The content (peak area%) of MDI in the main agent obtained in each Production Example (Production Examples 1 to 8) is gel permeation chromatography (GPC) (measuring instrument: “HLC-8120” (manufactured by Tosoh Corporation). Column: “TSKgel Multipore HXL-M” (manufactured by Tosoh Corporation, particle size: 5 μm, size: 7.8 mm ID × 30 cm × 4), carrier: tetrahydrofuran (THF), detector: differential refraction, sample: THF 0.5% solution) and obtained by conversion using a calibration curve obtained from measurement results of polystyrene (standard substance) by gel permeation chromatography.

  The results obtained by conducting the mixed viscosity measurement, the low-molecular eluate extraction test and the hardness measurement test in each Example and Comparative Example are the results of the composition of each polyurethane resin-forming composition (combination of main agent and curing agent and mass ratio). Tables 1 and 2 together with the NCO content in the isocyanate group-terminated prepolymer in the main agent (simply referred to as NCO content in Tables 1 and 2). Table 3 shows the viscosity of the main agent, the MDI content, and the NCO content in the isocyanate group-terminated prepolymer (simply referred to as NCO content in Table 3) in each production example.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the polyurethane resin-forming composition which can make compatible the low elution of the reaction material of MDI and glycerol, and the reduction of a mixing viscosity, and the sealing material using the said composition. . As described above, the cured resin obtained by curing the polyurethane resin-forming composition of the present invention has many excellent performances, particularly excellent low elution physical properties. Accordingly, the sealing material of the present invention, which is one of the cured resins, is used as a sealing material (binding material) for a hollow fiber membrane module (hollow fiber membrane filtration device) constituting a medical or industrial separation device. And can be suitably used as a sealing material for a hollow fiber membrane module.

Claims (6)

A polyurethane resin-forming composition for a hollow fiber membrane module sealing material comprising a main component (A) containing an isocyanate component and a curing agent (B) containing a polyol component,
As an isocyanate component constituting the main agent (A),
It is obtained by reacting polymeric MDI (a1), which is a mixture of diphenylmethane diisocyanate and polymethylene polyphenyl polyisocyanate, with aliphatic alcohol (a2) having 10 to 15 carbon atoms, and has an isocyanate group content of 15. Containing an isocyanate group-terminated prepolymer of 0 to 21.5% by weight,
As a polyol component constituting the curing agent (B),
At least one (b1) selected from the group consisting of castor oil and castor oil-based modified polyol, and a hydroxyl group-containing amine compound (b2),
Polyurethane resin-forming composition.   The polyurethane resin-forming composition according to claim 1, wherein the aliphatic alcohol (a2) has a side chain.   In the polymeric MDI (a1), the mass ratio of the diphenylmethane diisocyanate to the polymethylene polyphenyl polyisocyanate (mass of diphenylmethane diisocyanate / mass of polymethylene polyphenyl polyisocyanate) is 20/80 to 80/20. 3. The polyurethane resin-forming composition according to 1 or 2.   The polyurethane resin-forming composition according to any one of claims 1 to 3, wherein the hydroxyl group-containing amine compound (b2) is N, N, N ', N'-tetrakis [2-hydroxypropyl] ethylenediamine. object.   The sealing material obtained by hardening | curing the polyurethane resin-forming composition as described in any one of Claims 1-4.   A hollow fiber membrane module comprising the sealing material according to claim 5.