JP3971491B2 - Polyurethane resin forming composition for casting - Google Patents

Description

【００５２】
また、製造例１および比較製造例１〜３で得られたイソシアネート成分（Ａ−１）、（Ａ’−１）、（Ａ’−２）および（Ａ’−３）と、製造例２で得られたポリオール成分（Ｂ−１）とを、表２に示すように組み合わせてシール材を得た。このシール材を用いて下記のようにして評価を行った。
セルロース中空糸をポリカーボネート容器に挿入し、遠心成法によりシール材で固定した。４０℃で２日間養生後、血液回路接続部品を取り付けてモジュールを作成した。その後オートクレーブにより１２１℃で１時間蒸気加熱により滅菌処理を行った。
各２液混合液および得られた各モジュールについて下記試験方法により性能評価した。その結果を表２に示す。
【００５３】

【００５４】
【表２】

【００５５】
【発明の効果】
本発明の組成物は下記の効果を有する。
（１）イソシアネート成分の低温での長期保存安定性が極めて良好であるので、加熱再溶解等のわずらわしい作業が不要となり、従来のものを用いた場合に比べて作業性および生産性が格段に向上する。
（２）成形性、硬化樹脂物性等は、従来のカルボジイミド変性した４，４’−ＭＤＩ系のイソシアネート成分を用いたものと同等以上である。
上記効果を奏することから本発明の注型用ポリウレタン樹脂形成性組成物は、血液処理器等の人工臓器もしくは浄水器のシール材用として特に有用である。
また、電子回路基板の封止等の電気絶縁用途、光ファイバーケーブル接続部の封止等の止水用途、断熱アルミサッシの接着やアルミハニカムパネルの接着等の建材用途等にも使用できる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polyurethane resin-forming composition for casting, and particularly to a polyurethane resin-forming composition for casting which is suitable for use as a sealing material for a blood treatment device or a water purifier.
[0002]
[Prior art]
The polyurethane resin-forming composition for casting is used as a known technique, and the polyisocyanate component is usually 4,4′-diphenylmethane diisocyanate (hereinafter abbreviated as 4,4′-MDI) and castor oil or castor oil derivative polyol. Is used because of the strong crystallinity of 4,4'-MDI, but the prepolymer obtained easily solidifies at low temperatures (crystal precipitation) and is cast in cold temperatures. In operation, there was a difficulty that it was necessary to dissolve by heating.
As an improvement in the precipitation of crystals, one using liquefied diphenylmethane diisocyanate (carbodiimide-modified 4,4′-MDI) (Japanese Patent Publication No. 59-33605) has been proposed.
[0003]
[Problems to be solved by the invention]
However, even when this liquefied diphenylmethane diisocyanate is used, a precipitate is deposited when left for a long period of time and needs to be dissolved by heating before use, so that the storage stability is not sufficient.
[0004]
[Means for Solving the Problems]
As a result of intensive investigations to obtain a polyurethane resin-forming composition for casting with excellent long-term storage stability at low temperatures and excellent casting properties and mechanical properties of the resin, the present inventors have found that a specific isocyanate component It has been found that these characteristics can be obtained by using a polyol component and a polyol component, and the present invention has been achieved.
[0005]
That is, the present invention relates to a modified carbodiimide (A1) of diphenylmethane diisocyanate having a content of 2,4′-diphenylmethane diisocyanate of 5% by weight or more and a diphenylmethane diisocyanate having a content of 2,4′-diphenylmethane diisocyanate of 5% by weight or more. An isocyanate group-terminated urethane prepolymer (A2) from a modified carbodiimide (a) and a polyol (b), or an isocyanate component (A) composed of the polyisocyanate compound (A2) and a polyol component (B). It is a polyurethane resin-forming composition for casting.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, the content of 2,4′-diphenylmethane diisocyanate (hereinafter referred to as 2,4′-MDI) constituting the carbodiimide-modified product (A1) of diphenylmethane diisocyanate (MDI) in the isocyanate component (A) is usually 5 wt. % Or more, preferably 30% by weight or more, and more preferably 40 to 80% by weight. The carbodiimide modification rate of (A1) is usually 10 to 70%, preferably 20 to 60%, based on the weight of MDI. The modified carbodiimide may be used as (A1) as it is, or may be used as an isocyanate group-terminated urethane prepolymer (A2) from the modified carbodiimide (a) and the polyol (b).
[0007]
Examples of (b) include a low molecular polyol and / or a high molecular polyol having a hydroxyl value of 20 to 600 (polyether polyol, castor oil fatty acid ester polyol, polyester polyol, etc.).
[0008]
Low molecular polyols are divalent (ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, hydrogenated bisphenol A, etc.); (Glycerin, trimethylolpropane, hexanetriol, pentaerythritol, sorbitol, shoelace, etc.).
[0009]
Examples of the polyether polyol include one or more alkylene oxide (for example, ethylene oxide, propylene oxide, butylene oxide and a mixture of two or more of these) adducts of the above low molecular polyol and a ring-opening polymer of alkylene oxide. Specifically, polyethylene glycol, polypropylene glycol, polyoxytetramethylene glycol and the like are included.
The number average molecular weight of the polyether polyol is usually 200 to 2,000.
[0010]
Examples of the castor oil fatty acid ester-based polyol include castor oil, castor oil fatty acid ester obtained by transesterification of the above low molecular polyol or polyether polyol with castor oil, or esterification with castor oil fatty acid.
[0011]
Polyester polyols include polycarboxylic acids [aliphatic saturated or unsaturated polycarboxylic acids (adipic acid, azelaic acid, dodecanoic acid, maleic acid, fumaric acid, itaconic acid, dimerized linoleic acid, etc.) and / or aromatic polycarboxylic acids. A linear or branched polyester polyol from an acid (phthalic acid, isophthalic acid, etc.)] and a polyol (the aforementioned low molecular polyol and / or polyether polyol); a polylactone polyol [for example, the above low molecular polyol (2-3) (Substituted) caprolactone (ε-caprolactone, α-methyl-ε-caprolactone, ε-methyl-ε-caprolactone, etc.) as a catalyst (organometallic compound, metal chelate compound, fatty acid) Polyols subjected to addition polymerization in the presence of metal acylates) (Eg, polycaprolactone polyol)]; polyether ester polyol obtained by addition polymerization of alkylene oxide (ethylene oxide, propylene oxide, etc.) to a polyester having a carboxyl group and / or an OH group at the terminal; polycarbonate polyol and the like.
[0012]
Among these, a castor oil fatty acid ester-based polyol is preferable, and a castor oil is particularly preferable.
[0013]
Although the manufacturing method of isocyanate group terminal urethane prepolymer (A2) from said (a) and (b) is not specifically limited, The well-known method of making (a) and (b) react in nitrogen atmosphere in reaction container Is mentioned. The reaction temperature in the prepolymerization reaction is usually 30 to 140 ° C, preferably 60 ° C to 120 ° C. In addition, the reaction is usually carried out in the absence of a solvent. If necessary, a solvent inert to an isocyanate group [for example, an aromatic hydrocarbon (toluene, xylene, etc.), a ketone (methyl ethyl ketone, methyl isobutyl ketone, etc.) and two or more of these These solvents may be removed later by distillation.
[0014]
In (A2), the equivalent ratio (NCO / OH) of the NCO group in (a) to the hydroxyl group in (b) is usually 1.1 to 50, preferably 1.5 to 30, particularly preferably 2. ~ 20. The content of free isocyanate groups (NCO) in (A2) is usually 2 to 16% by weight, preferably 4 to 13% by weight.
[0015]
Further, as the isocyanate component (A), together with the above (A1) and / or (A2), if necessary, other aliphatic, cycloaliphatic, aromatic or araliphatic polyisocyanate, modified products thereof and isocyanate groups are contained. One or more polyisocyanate compounds selected from the group consisting of urethane prepolymers can be used in combination.
[0016]
Examples of the aliphatic polyisocyanate include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, 2,2,4-trimethylhexane diisocyanate, and lysine diisocyanate. 2,6-diisocyanatomethylcaproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanatohexanoate, etc. .
[0017]
Examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI), and bis (2-isocyanatoethyl) -4- Examples include cyclohexene-1,2-dicarboxylate.
[0018]
Examples of aromatic polyisocyanates include tolylene diisocyanate (2,4-form / 2,6-form = 80/20 mixture, 65/35 mixture, crude TDI, etc.), naphthylene diisocyanate (NDI), polymethylene poly Examples include phenyl polyisocyanate.
[0019]
Examples of the araliphatic polyisocyanate include xylylene diisocyanate (XDI), α, α, α ′, α′-tetramethylxylidene diisocyanate (TMXDI), diisocyanatoethylbenzene, and the like.
[0020]
Examples of the modified products of these polyisocyanate compounds include compounds obtained by modifying a part or all of the isocyanate groups of the polyisocyanates exemplified above to uretdione groups, uretoimine groups, urea groups, burette groups, isocyanurate groups, and the like.
[0021]
As the urethane prepolymer having an isocyanate group, at least one selected from the polyisocyanate compounds exemplified above and modified products thereof, and the same polyol (b) exemplified as the component (A2) are used. The isocyanate group terminal urethane prepolymer obtained by making it react is mentioned.
[0022]
The content of the 2,4′-MDI carbodiimide modified product in the isocyanate component (A) used in the present invention is usually 0.5 to 60% by weight, preferably 2 to 50% by weight based on the weight of (A). %. If the amount is less than 0.5% by weight, the effect of significantly improving long-term storage stability at low temperatures cannot be obtained. If the amount exceeds 60% by weight, the viscosity becomes high, so that good castability cannot be obtained.
[0023]
As a polyol component (B) used by this invention, what consists of a tertiary amino group containing polyol and a castor oil fatty-acid ester type polyol is preferable.
As the tertiary amino group-containing polyol, an oxyalkylenated derivative of an amino compound having at least two active hydrogen atoms can be used. This amino compound includes ammonia, alkanolamines, monoamines, and polyamines (aliphatic, aromatic, alicyclic or heterocyclic polyamines). Examples of these amino compounds include those described as amino compounds used for the production of tertiary amino group-containing polyether polyols described in JP-A Nos. 54-122396 and 54-101899. It is done.
[0024]
Specific examples of the amino compound include ammonia, alkanolamines [mono-, di- or trialkanol (2 to 4 carbon atoms) amine (diethanolamine, triethanolamine, etc.)], monoamines (aliphatic monoamines such as methylamine, Butylamine, stearylamine, etc .; aromatic amines such as aniline), polyamines [aliphatic polyamines such as alkylene (2 to 6 carbon atoms) diamines (ethylenediamine, propylenediamine, etc.); polyalkylene polyamines (diethylenetriamine, triethylenetetramine, etc.); Aromatic polyamines (phenylenediamine, tolylenediamine, diphenylmethanediamine, xylylenediamine, etc.); alicyclic polyamines (cyclohexylenediamine, isophoronediamine, etc.) ; Heterocyclic polyamines (piperazine and amino alkyl-substituted piperazines (such as amino ethyl piperazine)] and the like.
[0025]
These amino compounds are required to have at least two active hydrogen atoms, and those having 2 to 7, preferably 2 to 5 active hydrogen atoms are suitable. Two or more of these amino compounds may be used in combination.
[0026]
An oxyalkylenated derivative of an amino compound can be produced by various methods, but is generally produced by adding an alkylene oxide to an amino compound. Examples of the alkylene oxide include ethylene oxide (EO), propylene oxide (PO), 1,2-, 1,3- or 2,3-butylene oxide, tetrahydrofuran, styrene oxide, epichlorohydrin and the like. The alkylene oxides may be used alone or in combination of two or more. In the latter case, block addition, random addition or a combination of both may be used. Among the alkylene oxides, preferred are PO and / or EO, and particularly preferred are PO alone and a combined system of PO and EO (typically 30:70 to 99: 1, particularly 70:30 to 90 by weight). : 10). The reactivity can be further increased by tipping EO to the PO adduct to primaryize the terminal hydroxyl group.
[0027]
The addition of the alkylene oxide can be carried out in the usual manner, under normal pressure or in the presence of a catalyst or a catalyst (alkali catalyst, amine-based catalyst, acidic catalyst, etc.) (especially the latter stage of alkylene oxide addition). Done. The addition of alkylene oxide can be carried out directly on the amino compound or in the presence of a suitable medium [inert liquid (xylene, dimethylformamide, etc.) or an oxyalkylenated derivative of an amino compound prepared in advance].
[0028]
The added mole number of alkylene oxide is usually 1 mole or more, preferably 1 to 20 moles per active hydrogen atom of the amino compound.
[0029]
The hydroxyl value of the tertiary amino group-containing polyol can be arbitrarily changed within a range not slowing the curing rate, but is usually 25 or more, preferably 50 to 1,130, more preferably 100 to 800.
[0030]
Specific examples of preferable tertiary amino group-containing polyols include triethanolamine, tetrakishydroxypropylethylenediamine, pentakishydroxypropyldiethylenetriamine and the like.
[0031]
The content of the tertiary amino group-containing polyol in the polyol component (B) is usually 5 to 50% by weight, preferably 10 to 45% by weight. If the content of the tertiary amino group-containing polyol is less than 5% by weight, the curing reaction rate with the isocyanate component (A) is slow, so it is necessary to use a catalyst [amine-based, metal-based (tin, lead, etc.)]. These are not preferable because they are extracted from the cured product as an eluate. On the other hand, if it exceeds 50% by weight, curing is too fast and centrifugal molding becomes difficult.
[0032]
Examples of the castor oil fatty acid ester-based polyol in the polyol component (B) include the same as those exemplified in the section of the polyol (b) constituting the isocyanate group-terminated urethane prepolymer (A2). Preferred among these are castor oil, polyhydric alcohols (ethylene glycol, trimethylolpropane, etc.) and castor oil fatty acids, polyether polyols (polypropylene glycol, polyethylene glycol, etc.) and castor oil fatty acids, and these It is a mixture of two or more of.
The content of the castor oil fatty acid ester polyol in the (B) is preferably 25 to 95% by weight, and more preferably 50 to 90% by weight.
[0033]
Polyol (b) constituting the isocyanate group-terminated urethane prepolymer (A2) as a polyol component (B) together with a tertiary amino group-containing polyol and a castor oil fatty acid ester polyol or instead of the castor oil fatty acid ester polyol The same low molecular polyols, polyether polyols, and polyester polyols as those exemplified in the section) may be used.
[0034]
When the polyurethane resin is formed from the isocyanate component (A) and the polyol component (B) constituting the composition of the present invention, the NCO / OH equivalent ratio of (A) and (B) is usually 0.8-2. 0, preferably 0.9 to 1.5, more preferably 0.95 to 1.1. When the NCO / OH equivalent ratio is less than 0.8 or more than 2.0, unreacted (A) or unreacted (B) remains in the cured resin, which causes an increase in the amount of eluate. .
[0035]
The NCO content of the isocyanate component (A) in the present invention is usually 5 to 30% by weight, preferably 15 to 28% by weight. Moreover, the viscosity (25 degreeC) of this (A) is 50-2,000 mPa * s normally, Preferably it is 100-1,000 mPa * s.
[0036]
Moreover, the hydroxyl value of a polyol component (B) is 100-600 normally, Preferably it is 150-300. Moreover, the viscosity (25 degreeC) of this (B) is 50-2,000 mPa * s normally, Preferably it is 100-1,000 mPa * s.
[0037]
The composition of the present invention usually comprises a combination of two liquids of an isocyanate component (A) and a polyol component (B), and the two liquids are mixed and reacted at the time of use to form a polyurethane resin.
The isocyanate component (A) and the polyol component (B) can be reacted at room temperature by weighing each of a predetermined amount and then mixing with a static mixer or a mechanical mixer. The gelation time is usually 3 to 60 minutes, and 12 to 48 hours are required for complete curing. The time when the hardness stops changing is regarded as complete curing (reaction end point). In addition, it is also possible to shorten the time to complete hardening by making curing temperature high (for example, 30-50 degreeC).
[0038]
The viscosity of the two-liquid mixture composed of (A) and (B) (viscosity before casting, 25 ° C.) is usually 50 to 2,000 mPa · s, preferably 100 to 1,000 mPa · s.
[0039]
The hardness (Shore D; instantaneous value) of the cured resin obtained by reacting (A) and (B) is usually 30 to 77, preferably 40 to 75.
[0040]
The polyurethane resin-forming composition for casting of the present invention is particularly suitably used as a sealing material for a blood treatment device or a water purifier. Examples of the blood treatment device to be used include hollow fiber type, membrane type, and coil type artificial kidneys and clot separation modules. It can also be used for artificial organs such as artificial lungs.
[0041]
Specific usage of the composition of the present invention is shown below.
The isocyanate component (A) and the polyol component (B) are individually degassed under reduced pressure (0.1 mmHg × 2 hours). These two liquids are weighed in a predetermined amount and then mixed at room temperature, and the hollow fiber is embedded in a polycarbonate container by a centrifugal molding method. An example of the centrifugal molding method is described in JP-B-57-58963. Generally, hollow fibers such as cellulose, acrylic, polyvinyl alcohol, polyamide, and polysulfone are used as the hollow fibers to be embedded.
The resin gels 30 minutes to 1 hour after injection, and the module can be removed from the molding machine. Curing is performed at 40 ° C. for 2 days to complete the curing. Thereafter, the product is sterilized by steam heating for 1 hour at 121 ° C. using an autoclave to produce a product. Sterilization can also be carried out by methods other than steam heating, such as ethylene oxide gas or gamma irradiation.
[0042]
The polyurethane resin from the composition of the present invention has little shrinkage at the time of curing, and there is no fear that the hollow fiber in the hemodialyzer is crushed. Also, the adhesion to the hollow fiber is very good, and the amount of eluate from the cured resin is small.
[0043]
【Example】
EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto. In the following, “%” represents “% by weight”.
[0044]
Production Example 1
A carbodiimide-modified product (carbodiimide-modified product) of a mixture of 2,4′-MDI and 4,4′-MDI (weight ratio 50:50) was added to a 2 L four-necked flask equipped with a stirrer, a thermometer and a nitrogen introduction tube. (About 36% by weight) 916.2 g of polypropylene glycol (PPG) and 83.8 g of castor oil fatty acid monoester [manufactured by Ito Oil Co., Ltd .; “URIC H-53”], and 70-80 ° C. in a nitrogen stream. And reacted for 4 hours with stirring to obtain an isocyanate component (A-1). The (A-1) had a free isocyanate group (NCO) content of 25.0% and a viscosity of 200 mPa · s / 25 ° C.
[0046]
Production Example 2
A reaction vessel similar to Production Example 1 was charged with 810.0 g of castor oil and 190.0 g of tetrakishydroxypropylethylenediamine (THPEDA), stirred at 40 to 50 ° C. for about 30 minutes and mixed uniformly to obtain a polyol component (B-1 ) This product had an OH value of 279 and a viscosity of 1,100 mPa · s / 25 ° C.
[0047]
Comparative production example 1
In a reaction vessel similar to Production Example 1, carbodiimide modified 4,4′-MDI [manufactured by Nippon Polyurethane Co., Ltd .; “Millionate MTL”] 878.5 g and PPG castor oil fatty acid monoester [manufactured by Ito Oil Co., Ltd .; “URIC H-53”] 121.5 g was charged and reacted at 70-80 ° C. for 4 hours to obtain an isocyanate component (A′-1) having an NCO content of 25.0% and a viscosity of 200 mPa · s / 25 ° C. It was.
[0048]
Comparative production example 2
In the same reaction vessel as in Production Example 1, 4,6.0'-MDI [manufactured by Nippon Polyurethane Co., Ltd .; “Millionate MT”] 786.0 g and PPG castor oil fatty acid monoester [manufactured by Ito Oil Co., Ltd .; H-53 "] 214.0 g was charged and reacted at 70-80 ° C for 4 hours to obtain an isocyanate component (A'-2) having an NCO content of 25.0 wt%. This was solid at room temperature.
[0049]
Comparative production example 3
In the same reaction vessel as in Production Example 1, carbodiimide-modified 4,4′-MDI [manufactured by Nippon Polyurethane Co., Ltd .; “Millionate MTL”] 500.0 g and HDI bifunctional prepolymer [manufactured by Asahi Kasei Co., Ltd .; D-101 "], 500.0 g, was added and stirred at 40-50 ° C for 1 hour under a nitrogen stream to obtain an isocyanate component (A'-3). The (A′-3) had an NCO content of 24.5% and a viscosity of 200 mPa · s / 25 ° C.
[0050]
Example 1 and Comparative Examples 1-3
The isocyanate components (A-1), (A′-1), (A′-2) and (A′-3) obtained in Production Example 1 and Comparative Production Examples 1 to 3 were placed in 100 ml glass bottles, respectively. After sealing with nitrogen gas, it was sealed and stored in a constant temperature bath at 25 ° C. and 0 ° C., and the change in appearance over time (storage stability) was examined. The results are shown in Table 1.
It can be seen from Table 1 that the storage stability of Example 1 is much better than that of Comparative Examples 1 to 3.
[0051]
[Table 1]

[0052]
In addition, the isocyanate components (A-1), (A′-1), (A′-2) and (A′-3) obtained in Production Example 1 and Comparative Production Examples 1 to 3 and Production Example 2 The obtained polyol component (B-1) was combined as shown in Table 2 to obtain a sealing material. Evaluation was performed as follows using this sealing material.
The cellulose hollow fiber was inserted into a polycarbonate container and fixed with a sealing material by a centrifugal method. After curing at 40 ° C. for 2 days, a blood circuit connection component was attached to prepare a module. Thereafter, sterilization was performed by steam heating at 121 ° C. for 1 hour in an autoclave.
Each two-component liquid mixture and each obtained module were evaluated for performance by the following test method. The results are shown in Table 2.
[0053]

[0054]
[Table 2]

[0055]
【The invention's effect】
The composition of the present invention has the following effects.
(1) The long-term storage stability of isocyanate components at low temperatures is extremely good, eliminating the need for cumbersome operations such as re-dissolution by heating, and significantly improving workability and productivity compared to the conventional products. To do.
(2) Formability, cured resin physical properties and the like are equal to or higher than those using a conventional carbodiimide-modified 4,4′-MDI isocyanate component.
Because of the above effects, the cast polyurethane resin-forming composition of the present invention is particularly useful as a sealing material for artificial organs such as blood treatment devices or water purifiers.
It can also be used for electrical insulation applications such as sealing of electronic circuit boards, water-stopping applications such as sealing of optical fiber cable connection parts, and building material applications such as bonding of heat insulating aluminum sashes and bonding of aluminum honeycomb panels.

Claims (5)

  Diphenylmethane diisocyanate modified carbodiimide (A1) having a content of 2,4′-diphenylmethane diisocyanate of 5% by weight or more and carbodiimide modified product of diphenylmethane diisocyanate having a content of 2,4′-diphenylmethane diisocyanate of 5% by weight or more (a ) And a polyol (b), an isocyanate group-terminated urethane prepolymer (A2) or an isocyanate component (A) comprising the polyisocyanate compound (A2) and a polyol component (B). Forming composition.   The composition according to claim 1, wherein (A2) is an isocyanate group-terminated urethane prepolymer from (a) and a castor oil fatty acid ester-based polyol.   The composition according to claim 1 or 2, wherein the content of the carbodiimide modified product of 2,4'-diphenylmethane diisocyanate in (A) is 0.5 to 60% by weight based on the weight of (A).   (B) comprises a tertiary amino group-containing polyol and a castor oil fatty acid ester-based polyol, and the content of the tertiary amino group-containing polyol is 5 to 50% by weight based on the weight of (B). The composition in any one of 1-3.   The composition according to any one of claims 1 to 4, which is used as a sealing material for a hollow fiber blood treatment device or a water purifier.