JPH0625383A - Composition for forming polyurethane resin for casting - Google Patents

Abstract

PURPOSE:To provide the subject composition composed of a compound containing NCO group, a compound containing t-amino group and a specific compound, having low soluble material content, low viscosity and excellent workability and suitable as a sealing material for membrane module such as blood-treating apparatus and artificial organ. CONSTITUTION:This composition is composed of (A) a compound having NCO group (preferably a combination of diphenylmethane diisocyanate with an NCO- terminated urethane prepolymer derived from castor oil polyol), (B) a polyol having t-amino group (preferably tetrakis[2-hydroxypropyl]-ethylenediamine) and (C) a block compound of an isocyanate compound blocked with an ester of a castor oil fatty acid and a monool (preferably tolylene diisocyanate completely blocked with a castor oil fatty acid methyl ester). The NCO/OH equivalent ratio of the total component of the composition is preferably 0.8-1.3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyurethane resin-forming composition for casting, and more particularly to a polyurethane resin-forming composition for casting suitable for use as a sealing material for membrane modules such as blood processors and water purifiers.

[0002]

BACKGROUND OF THE INVENTION Casting polyurethane resin-forming compositions have been used as well known in the art, and limited compositions may be used, for example, for electrical insulation (see, for example, JP-B-59-336).
No. 05) is known. Further, as a sealing material used for embedding hollow fibers for separating devices such as blood and water, for example, in JP-A-60-58156, a curable composition comprising hexamethylene diisocyanate, an amine polyol and a non-amine polyol is used. However, JP-A-3-137116 proposes a composition comprising 2,4'-diphenylmethane diisocyanate and a polyether polyol.

[0003]

When the hollow fiber is stored, glycerin is usually impregnated and attached for the purpose of protecting the performance of the separation membrane. Particularly in recent devices such as artificial kidneys for dialysis, the pore diameter of the hollow fiber is large, and the amount of glycerin attached is further increasing during the storage of the hollow fiber for the purpose of protecting the microporous structure. Therefore, when embedding the hollow fiber,
In the above composition, when contacted with glycerin, a reaction product of an isocyanate compound and glycerin in the composition is produced,
Since this reaction product has a low molecular weight, there is a problem that it elutes in blood. To essentially reduce the amount of eluate, it is necessary to reduce the amount of the reaction product having a low molecular weight of glycerin and the low molecular weight isocyanate compound, and as a countermeasure,
(1) A method of reducing the content of low molecular weight components in the isocyanate component, (2) a method of using only a tertiary amino group-containing polyol having a higher reactivity with an isocyanate component than glycerin as a substantial polyol component, etc. However, in both cases, the viscosity of the composition is significantly increased, resulting in poor castability, high incidence of defective products, and poor workability. An object of the present invention is to obtain a polyurethane resin-forming composition for casting having a small amount of eluate, a low viscosity, and good workability.

[0004]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have used a tertiary amino group-containing polyol as a substantial polyol component.
However, the inventors have found a composition containing a specific blocked compound which can reduce the viscosity of the composition and which does not elute even when incorporated into a cured product, and arrived at the present invention.

That is, the present invention comprises a compound (1) having an isocyanate group, a polyol (2) having a tertiary amino group and a blocked product (3) of an isocyanate compound with an ester of castor oil fatty acid and monool. Is a polyurethane resin-forming composition for casting.

In the present invention, the compound (1) having an isocyanate group is one selected from the group consisting of aliphatic, alicyclic or aromatic isocyanate compounds, modified products thereof and urethane prepolymers having an isocyanate group. The above compounds may be mentioned.

The aliphatic isocyanates include aliphatic polyisocyanates [ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate,
1,6,11-undecane triisocyanate, 2,
2,4-trimethylhexane diisocyanate, lysine diisocyanate, 2,6-diisocyanate methyl caproate, bis (2-isocyanate ethyl) fumarate, bis (2-isocyanate ethyl) carbonate, 2-isocyanate ethyl-2,6-diisocyanate hexa Noate, tetramethylxylidene diisocyanate (TMXDI), etc.] and the like.

Examples of the alicyclic isocyanate include alicyclic polyisocyanate [isophorone diisocyanate (IP
DI), dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI),
Bis (2-isocyanatoethyl) -4-cyclohexene-1,2-dicarboxylate and the like] and the like.

As the aromatic isocyanate, aromatic polyisocyanate [tolylene diisocyanate (TD
I), diphenylmethane diisocyanate (MDI),
Naphthylene diisocyanate, xylylene diisocyanate, diethylbenzene diisocyanate, etc.] and the like.

As the modified products of the aliphatic, alicyclic or aromatic isocyanate compound, N of the above-exemplified compounds is used.
A compound in which a part of the CO group is modified into a carbodiimide group, a uretdione group, a uretoimine group, a urea group, a buret group, an isocyanurate group, or the like can be given.

The urethane prepolymer having an isocyanate group is an NCO group-terminated urethane prepolymer obtained by reacting the above-exemplified aliphatic, alicyclic or aromatic isocyanate compound or a modified product thereof with an active hydrogen-containing compound. Is mentioned.

As the active hydrogen-containing compound for producing the NCO-terminated urethane prepolymer, a low molecular weight polyol having a molecular weight of less than 200, and a molecular weight of 200 to 1 are used.
Examples include 50,000 polyols and castor oil-based polyols.

As the low molecular weight polyol having a molecular weight of less than 200, ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol, diethylene glycol, triethylene glycol, dipropylene. Examples thereof include glycol, glycerin, trimethylolpropane, pentaerythritol, and sorbitol.

Examples of the polyol having a molecular weight of 200 to 10,000 include polyester polyol, polyether polyol, polyether polyester polyol, polyester amide polyol, acrylic polyol and polyhydroxyalkane. As castor oil-based polyol, castor oil, ester of castor oil fatty acid and polyol (diglyceride of castor oil fatty acid, monoglyceride, mono, di or triester of castor oil fatty acid and trimethylolpropane, castor oil fatty acid and polyethylene glycol, Mono- or diesters of polypropylene glycol or polytetramethylene glycol, etc.) and the like.

Among the compounds exemplified as the compound (1) having an isocyanate group, preferred are one or more selected from aliphatic, alicyclic or aromatic polyisocyanate compounds and modified products thereof, and an NCO group-terminated urethane. A combination with a prepolymer, particularly preferred is an NCO derived from a castor oil-based polyol.
It is a combination use of a terminal urethane prepolymer and MDI.

In the present invention, examples of the polyol (2) having a tertiary amino group include oxyalkylenated derivatives of amino compounds having at least two active hydrogen atoms. As this amino compound, JP-A-54-122396 and JP-A-54-10189 are known.
Examples of the amino compounds used in the production of the tertiary amino group-containing polyether polyol described in JP-A No. 9-90 are cited.

Specific examples of the amino compound include ammonia; alkanolamines [mono-, di- or trialkanol (C2-4) amines (such as triethanolamine)]; monoamines [aliphatic monoamines (monomethylamine, stearyl). Amines, etc.), aromatic monoamines (aniline, etc.); polyamines [alkylene (C2-6) diamines (ethylenediamine, propylenediamine, etc.), polyalkylenepolyamines (diethylenetriamine, triethylenetetramine, etc.), aromatic polyamines (phenylenediamine) , Tolylenediamine, diphenylmethanediamine, xylylenediamine, etc.),
Examples include alicyclic polyamines (cyclohexylenediamine, isophoronediamine, etc.), heterocyclic polyamines (piperazine, aminoalkyl-substituted piperazines (aminoethylpiperazine, etc.), etc.] The active hydrogen atom in these amino compounds is usually It is 2 to 7, preferably 2 to 5.

Although the oxyalkylenated derivative of the amino compound can be produced by various methods, it is generally produced by adding an alkylene oxide to the amino compound.
As alkylene oxide, ethylene oxide (E
O), propylene oxide (PO), 1,2-, 1,
Examples thereof include 3- or 2,3-butylene oxide and tetrahydrofuran. The alkylene oxides may be used alone or in combination of two or more, and in the latter case, block addition or random addition may be performed. Among those exemplified as the alkylene oxide, preferable ones are PO and / or
Or EO, and particularly preferred is PO alone or a combination system of PO and EO (weight ratio 70:30 to 90:
10). In the case of adding a terminal PO, the reactivity can be increased by further tipping EO to make it primary. The number of moles of alkylene oxide added is usually 0.2 mol or more and preferably 0.8 to 20 mol per 1 active hydrogen atom of the amino compound.

The hydroxyl equivalent of the polyol (2) having a tertiary amino group can be freely changed in order to adjust the curing rate, but it is usually 25 or more, preferably 50 to 125.
It is 0, more preferably 50 to 800.

Specific examples of the polyol (2) having a tertiary amino group include triethanolamine, N, N, N-.
Tris [2-hydroxyethyl] amine, N, N, N-
Examples include tris [2-hydroxypropyl] amine, tetrakis [2-hydroxypropyl] ethylenediamine, tetrakis [2-hydroxyethyl] ethylenediamine, pentakis [2-hydroxypropyl] diethylenetriamine, pentakis [2-hydroxyethyl] diethylenetriamine. Of these, preferred are tetrakis [2-hydroxypropyl] ethylenediamine and pentakis [2-hydroxypropyl] diethylenetriamine.

In the present invention, among the blocked compounds (3), the isocyanate compound is selected from the group consisting of aliphatic, alicyclic or aromatic isocyanate compounds, modified products thereof and low molecular weight urethane prepolymers having an isocyanate group. One or more compounds selected may be mentioned. Examples of the aliphatic, alicyclic or aromatic isocyanate compound are the same as those exemplified in the section of the compound (1) having an isocyanate group.
As the modified product of the aliphatic, alicyclic or aromatic isocyanate compound, the same as those exemplified in the item (1) can be mentioned. The low molecular weight urethane prepolymer having an isocyanate group is the same as that exemplified in the item (1), and examples thereof include low molecular weight ones. Among these, preferred are aliphatic, alicyclic or aromatic polyisocyanate compounds, modified products thereof and low molecular weight urethane prepolymers having two or more isocyanate groups, and more preferred are aliphatic and alicyclic compounds. Formulas or aromatic polyisocyanate compounds, particularly preferred are TDI and MDI.

In the blocked product (3), the castor oil fatty acid may be a mixture of fatty acids obtained by decomposing castor oil. Other than this, among the fatty acid components constituting castor oil, molecules such as ricinoleic acid can be used. OH group and CO in
It is sufficient that the main component is a fatty acid having one OH group each. The monool has 1 to 1 carbon atoms.
20 linear or branched aliphatic monoalcohols [methanol, ethanol, iso-propanol, dodecyl alcohol, etc.], alicyclic monoalcohols [cyclohexanol, etc.], araliphatic monoalcohols [benzyl alcohol, etc.], monohydric phenols [Phenol, naphthol, cresol, nonylphenol, etc.] and the like.

As the blocked product (3), a completely blocked product is usually used, but a partially blocked product having an isocyanate group remaining may be used together with the completely blocked product. However, when it is desired to make the composition of the present invention into a two-part liquid consisting of the liquid consisting of (1) and the liquid consisting of (2), the completely blocked product can be blended in either liquid, but the partially blocked product is (1). Need to be blended with. Particularly preferred as the blocked product (3) is a completely blocked product of castor oil fatty acid methyl ester of TDI.

An example of the method for producing the blocked compound (3) is as follows. Castor oil is transesterified with the monol, or the castor oil fatty acid and the monol are esterified to obtain an ester of the castor oil fatty acid and the monol. The blocked product (3) is obtained by subjecting this ester to the urethane reaction of the isocyanate compound. In this case, the NCO / OH equivalent ratio is usually 3.2.
It is ˜0.9, and in the case of a completely blocked product, the equivalent ratio is 1.0, and the reaction end point is set when the absorption due to the NCO group disappears using an infrared spectrometer. When using a partially blocked compound, set this equivalent ratio to greater than 1.0
The reaction end point is reached when O% does not change.

The NCO / OH equivalent ratio of all the components (1), (2) and (3) in the composition of the present invention is usually 0.
It is 5 to 2.0, preferably 0.8 to 1.3.

When the composition of the present invention is to be cured immediately, all the components (1), (2) and (3) may be mixed together at the time of use to form a composition. When a storage period is required, it is preferable to use two liquids, an isocyanate-containing liquid consisting of (1) and a polyol-containing liquid consisting of (2), in order to adjust the liquid ratio during use. In that case, when (3) is a completely blocked product, it may be added to any liquid, but when (3) is a partially blocked product, it must be added to an isocyanate-containing liquid. A preferred combination in the case of these two liquids is a combination of a liquid (A liquid) containing (1) or (1) and (3) and a liquid (B liquid) containing (2) and (3). is there. That is,
When the viscosity of (1) is high in the liquid A (for example, when there are many NCO urethane prepolymers), the viscosity may be adjusted with the liquid (3), and in the liquid B, the high viscosity of the liquid (2) is adjusted with the liquid (3). .

The amount of (3) based on the total weight of (1), (2) and (3) in the composition of the present invention is usually 5 to 6.
It is 0%, preferably 10 to 50%. The amount of (3) is 5
If it is less than 60%, the viscosity reduction is insufficient, and if it exceeds 60%, the strength of the resin decreases, which is not preferable. Incidentally, together with the polyol (2) having a tertiary amino group, if necessary,
Other low-viscosity polyols may be blended within a range that satisfies the required values such as the amount of eluate.

The gelling time when all the components constituting the composition of the present invention are blended is usually 2 to 60 minutes, and it usually takes 12 to 72 hours at normal temperature for complete curing, but the curing temperature is high (30 The temperature until complete curing can be shortened by adjusting the temperature to 60 ° C.

The composition of the present invention is used for casting, in particular, blood treatment devices (hollow fiber type, membrane type or coil type, artificial kidneys, blood separation modules, etc.), artificial organs (artificial lungs, etc.), water purifiers. It is suitable for the sealing material of the membrane module such as.

As an example of the use of the composition of the present invention, an example for a hemodialyzer is shown below. A liquid (A liquid) containing (1) or (1) and (3) and a liquid (B liquid) containing (2) and (3) were separately prepared, and degassed under reduced pressure (0.
1 mmHg × 2 hours). After weighing these two liquids, they are mixed at room temperature, and a hollow fiber is formed into a container by a centrifugal molding method (consisting of polycarbonate resin, acrylonitrile-styrene resin, acrylonitrile-styrene-butadiene resin, etc.).
Embed in. An example of the centrifugal molding method is JP-B-57-58963.
It is described in Japanese Patent Publication No. As the hollow fiber to be embedded, generally, a cellulose-based, acrylic-based, polyvinyl alcohol-based, polyamide-based, polysulfone-based fiber, etc. containing 30 to 80% by weight of glycerin is used. The resin gels 30 minutes to 1 hour after injection and the module can be removed from the molding machine. Cure at 40 ° C. for 2 days to complete the cure. Then, it is sterilized by steam heating at 121 ° C. for 1 hour using an autoclave, and commercialized. The sterilization treatment can also be carried out by a method other than steam, for example, ethylene oxide gas treatment or γ-ray irradiation. The polyurethane resin obtained by curing the composition of the present invention has little shrinkage upon curing, and therefore, there is no concern that the hollow fiber in the hemodialysis device is pressed and crushed. Also, the adhesion to the hollow fiber is very good, and the amount of polyurethane resin and the eluate of the sealing portion is small.

[0031]

The present invention will be further described with reference to the following examples, but the present invention is not limited thereto. In the following,% means% by weight. The castor oil fatty acid used is a mixture of fatty acids obtained by decomposing castor oil. Production Example 1 2 L capacity 4 equipped with a stirrer, thermometer and nitrogen inlet tube
A two-necked flask was charged with 500 g of 2,4′-tolylene diisocyanate (hereinafter referred to as TDI) and 1000 g of castor oil, and heated to 70 to 80 ° C. with stirring under a nitrogen stream.
Isocyanate group-terminated prepolymer (1-
1) was obtained. This had an NCO content of 8.0% and a viscosity of 70,000 cps / 25 ° C.

Production Example 2 TDI (500 g) and castor oil fatty acid methyl ester (1000 g) were charged in the same reaction vessel as in Production Example 1 and reacted under the same conditions as in Production Example 1 to obtain TDI castor oil fatty acid partially blocked product (3-1). It was The NCO content of this product is 8.0.
%, The viscosity was 560 cps / 25 ° C.

Production Example 3 TDI (300 g) and castor oil fatty acid methyl ester (1200 g) were charged in the same reaction vessel as in Production Example 1 and reacted under the same conditions as in Production Example 1 to obtain TDI castor oil fatty acid completely blocked product (3-2). It was The viscosity was 720 cps / 25 ° C.

Production Example 4 450 g of (1-1) was placed in the same reaction vessel as in Production Example 1.
(3-1) 300 g and 4,4'-diphenylmethane diisocyanate (hereinafter, referred to as 4,4'-MDI) and 2,4'-diphenylmethane diisocyanate (hereinafter,
2,4'-MDI) (50:50) 2
50 g was charged and the mixture was stirred at 70 ° C. for 1 hour under a nitrogen stream to obtain a polyisocyanate-containing liquid (A-1). N of this thing
CO content is 14.4%, viscosity is 3030cps / 25 ° C
Met.

Production Example 5 Instead of 450 g of (1-1) and 300 g of (3-1),
A polyisocyanate-containing liquid (A-2) was obtained in the same manner as in Production Example 4 except that 750 g of (1-1) was used. This product has an NCO content of 14.4% and a viscosity of 12000 cp.
It was s / 25 ° C.

Production Example 6 In the same reaction vessel as in Production Example 1, 700 g of (3-2) and tetrakishydroxypropylethylenediamine (TH were added).
PEDA) (300 g) was charged, and the mixture was stirred at 50 ° C. for 30 minutes and uniformly mixed to obtain a polyol-containing liquid (B-1). This product has a hydroxyl value of 226 and a viscosity of 3150 cps / 2.
It was 5 ° C.

Production Example 7 In a reaction vessel similar to that of Production Example 1, 350 g of castor oil and trimethylolpropane monoester 3 of castor oil fatty acid were used.
50 g and THPEDA 300 g were charged, and Production Example 6
A polyol-containing liquid (B-2) was obtained in the same manner as in. This product had a hydroxyl value of 389 and a viscosity of 3280 cps / 25 ° C.

Examples 1 to 3 and Comparative Examples 1 and 2 By combining the polyisocyanate-containing liquid and the polyol-containing liquid shown in Table 1 as shown in Table 1, the two-part properties of Examples 1 to 3 and Comparative Examples 1 and 2 were obtained. The composition for a sealing material of

[0039]

[Table 1]

Modules were prepared as follows using each of the sealant compositions. Cellulosic hollow fibers containing 75% by weight of glycerin were inserted into a polycarbonate container and fixed with a two-liquid mixture of each sealing material composition by a centrifugal molding method. After curing at 45 ° C. for 2 days, a blood circuit connecting part was attached to prepare a module. Then, sterilization was performed by steam heating at 121 ° C. for 1 hour in an autoclave.

Table 2 shows the test results of the initial mixing viscosity, the elution test result, and the defective sealing rate as the performance items of the sealing material. The eluent test method is as follows. Eluate test method A hollow fiber bonded portion for one dialyzer is cut into 1 cm squares, 200 ml of deionized water is added, and the mixture is gently shaken and extracted at 40 ° C. for 2 hours. After allowing to cool, 1.0 ml of the supernatant is taken and deionized water is added to make exactly 5.0 ml. This solution was used as a test solution, and deionized water was used as a control.
The maximum value of absorbance at 70 nm was measured.

[0042]

[Table 2]

Note) Initial viscosity of mixing: The viscosity immediately after mixing the isocyanate-containing liquid and the polyol-containing liquid at 45 ° C. so as to have an NCO / OH equivalent ratio of 1.05 and uniformly mixing them. Poor sealing rate: Number of molded products in which liquid leakage occurred due to defective sealing (per 100 molded products) In each of Examples 1 to 3, the defective sealing rate was low and the initial mixing viscosity was low as compared with Comparative Example 1. Was also good. In Comparative Example 2, the initial mixing viscosity was about the same as in Examples 1 to 3, but the amount of eluate was large and it was unsuitable.

[0044]

The composition of the present invention has the following effects. 1. During molding, the liquid viscosity before casting is low, so moldability is good and the incidence of defective products is low. 2. When the composition of the present invention is used for a sealant such as an artificial kidney dialyzer, the amount of the eluate is extremely small, so that the amount of the eluate eluted from the sealant into the blood is small and the safety to the human body is enhanced. Since the composition of the present invention exerts the above-mentioned effects, the composition of the present invention is used for casting, in particular, blood treatment device (hollow fiber type, membrane type or coil type, artificial kidney, blood pressure separation module, etc.), artificial organ (artificial lung). Etc.), and is suitable as a sealing material for membrane modules such as water purifiers. In addition, since the castor oil-based polyol, which has good moldability and good insulation performance, is used as a component, it can be used for electrical insulation such as sealing of electronic circuit boards.

Claims (5)

[Claims] 1. A compound (1) having an isocyanate group, a polyol (2) having a tertiary amino group, and a blocked product (3) of an isocyanate compound with an ester of castor oil fatty acid and monool. A polyurethane resin-forming composition for casting. 2. A group consisting of an isocyanate compound constituting the blocked compound (3), which is an aliphatic, alicyclic or aromatic polyisocyanate compound, a modified product thereof and a low molecular weight urethane prepolymer having two or more isocyanate groups. The composition according to claim 1, which is one or more compounds selected from the following. 3. A compound (1) having an isocyanate group
Is a compound of one or more selected from the group consisting of an aliphatic, alicyclic or aromatic isocyanate compound, a modified product thereof and a urethane prepolymer having an isocyanate group. 4. A liquid (liquid A) containing (1) or (1) and (3), and a liquid (liquid B) containing (2) and (3).
The composition according to any one of claims 1 to 3, which is composed of two liquids. 5. The composition according to claim 1, which is used as a sealing material for a membrane module.