JPH06157708A - Composition for polyurethane-based elastomer - Google Patents

Abstract

PURPOSE:To obtain a composition composed of a specified modified compound, a polyisocyanate containing a terminal NCO group-containing prepolymer and a polyol-based curing agent, excellent in heat resistance, exhibiting a high elasticity and high physical properties and useful as a sealant or a binder for a dialysis type artificial organ. CONSTITUTION:A curing agent (A) composed of an amine-based polyol or another kind of polyol is blended with a polyisocyanate (B) composed of a modified compound synthesized by partly changing NCO groups of hexamethylene diisocyanate to a polyol addition compound and subsequently converting it to an isocyanurate and a terminal NCO group-containing prepolymer. A di-or tri-functional polyol having <=3000 molecular weight is reacted with <=15wt.% NCO groups of HDI to convert HDI to its addition compound.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyurethane elastomer composition. More specifically, the present invention relates to a composition for a polyurethane-based elastomer used as a polyurethane-based sealant, a binder, and the like.

[0002]

2. Description of the Related Art Polyurethane is a polymer compound having ???-NHCOO ??? in the main chain repeating unit obtained industrially by reacting an organic polyisocyanate with a polyol having a polyester structure or a polyol having a polyether structure. However, depending on the combination of raw materials, it has a wide range of uses such as polyurethane foam, polyurethane rubber, adhesives, fibers and paints.

For example, in a hollow fiber binding agent for a medical or industrial fluid separation device using an electrical sealant and a hollow fiber separation membrane, tolylene diisocyanate (TDI), diphenylmethane diisocyanate ( Aromatic isocyanate such as MDI) or hexamethylene diisocyanate (H
DI), hydrogenated MDI, isophorone diisocyanate (I
A prepolymer obtained by reacting a non-aromatic isocyanate such as PDI) with a castor oil-based polyol such as castor oil or alcohol-modified castor oil, or a polyether polyol such as polypropylene glycol or polyethylene glycol is used as a curing agent (active agent). As the hydrogen-containing compound), castor oil-based polyols such as castor oil and alcohol-modified castor oil, polypropylene glycol, polyethylene glycol and the like are used.

For these sealants and binders, low-viscosity systems that cure quickly at low temperatures have also been studied, and problems with workability and moldability are decreasing. However, in terms of physical properties, the use is limited because of low elasticity, low strength, and poor durability.

On the other hand, in a two-component polyurethane for industrial rolls for paper making, iron making, printing, paper feed rolls, cleaning blades, etc., the above-mentioned aromatic or non-aromatic isocyanate and polyethylene adipate, polybutylene are used. A prepolymer obtained by reacting a polyester polyol such as adipate or a polyether polyol such as polytetramethylene ether glycol or polypropylene glycol is used, and 4,4′-methinebis (2-) is used as a curing agent (active hydrogen-containing compound). A highly elastic and high physical property resin is obtained by reacting and curing with an aromatic amine such as chloroaniline) or 4,4′-methylenedianiline or an aliphatic glycol such as 1,4-butanediol or trimethylolpropane. Widely used in industrial fields There.

However, these systems have low reactivity at low temperatures, and heat curing at 100 ° C. or higher is required to obtain high physical properties. Further, the prepolymer of polyisocyanate and polyol has a high viscosity, and it is difficult to cast into a fine portion.

Further, as a means for accelerating the curability at low temperature, a heavy metal catalyst such as Sn, Pb, Zn, Cd or an amine catalyst such as triethylenediamine or triethylamine may be added, but the reactivity may be deteriorated due to deactivation. In addition to the potential for instability, there is a problem in medical applications that it may be dissolved in body fluids and adversely affect the living body. Further, the conventional resins have drawbacks such as too high hardness and brittleness, and improvement thereof is desired.

[0008]

DISCLOSURE OF THE INVENTION The present invention provides a drawback of conventional polyurethane-based sealants and binders, namely, to obtain a resin having high elasticity and high physical properties, high reactivity, and high productivity. If the viscosity is high, heat curing is required, and on the contrary, the one that cures quickly at low temperature has low physical properties and its application is limited, and further, the amount of eluate increases and it is not biocompatible, and It is to improve that the hardness is too high and brittle.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to improve the conventional drawbacks, and as a result, modified products obtained by converting a part of the NCO groups of HDI to urethane and then converting to isocyanurate ( The inventors have found that the improvement can be achieved by using A) and the NCO group-terminated prepolymer (B) in combination, and have completed the present invention.

That is, the present invention provides a polyurethane elastomer composition comprising a polyisocyanate and a curing agent, wherein the polyisocyanate is converted to isocyanurate after a part of the NCO group of hexamethylene diisocyanate is converted to a polyol adduct. Modified product (A) and NC
The present invention relates to a polyurethane elastomer composition comprising an O group-terminated prepolymer (B) and, as the curing agent, an amine polyol (C) and / or a non-amine polyol (D). .

The polyisocyanate which can be used in the present invention is a modified product (A) in which a part (15% by weight or less) of all NCO groups of HDI is converted to a polyol adduct and then isocyanurate-ized. As the polyol for obtaining the polyol adduct, a polyol having a molecular weight of 3000 or less
~ Trifunctional polyols are suitable. As the diol, ethylene glycol, diethylene glycol, 1,3-butanediol (1,3BD), 1,4-butanediol, propylene glycol, dipropylene glycol,
Examples include dihydric alcohols such as neopentyl glycol and 1,6-hexane glycol (1,6HD), polyester polyols, and polyether polyols. Examples of triols include trihydric alcohols such as glycerin, trimethylolethane and trimethylolpropane, polyester polyols or polyether polyols. Polyols can also be used in these blend systems. The urethane conversion rate is preferably 15% by weight or less based on the total isocyanate. If it is 15% by weight or more, the characteristics of the isocyanurate-forming bond formed thereafter cannot be sufficiently exhibited. A method of converting 15% by weight or less of all NCO groups of HDI into a polyol adduct and then converting it to isocyanurate is disclosed in JP-A-57-
It is described in Japanese Patent No. 47321. In the isocyanurate-forming reaction, a metal salt of carboxylic acid is used as a catalyst, and a phenolic droxy compound, a
Examples include primary amines.

NC which can be used in the present invention
The O group-terminated prepolymer is obtained by reacting an NCO group and an active hydrogen group, and examples of the compound having an NCO group for obtaining the prepolymer include aromatic diisocyanates such as MDI, TDI, and naphthylene. 1,
5-diisocyanate, 1,3- and 1,4-phenylene diisocyanate, triphenylmethane-4,4 ',
Aliphatic or alicyclic diisocyanates such as 4 ″ -triisocyanate and polyphenylene polymethylene polyisocyanate such as HDI, 1,12-dodecane diisocyanate, cyclobutane-1,3-diisocyanate, cyclohexane-1,3- and-1,4 -Diisocyanates, IPDI, 2,4- and 2,6-hexahydrotoluylene diisocyanates, hexahydro-1,3
-And -1,4-phenyl diisocyanate, perhydro-2,4 'and 4,4'-diphenylmethane diisocyanate, and the like. Polyisocyanate compounds include
For example, 4,4 ', 4 "-triphenylmethane triisocyanate, diphenyl-4,6,4', triisocyanate 2,4,4 'diphenyl ether triisocyanate, polyphenylene polymethylene polyisocyanate, etc. Some are modified to biuret, allophanate, carbodiimide, oxazolidone, amide, imide and the like.

Examples of the compound having an active hydrogen group for obtaining a prepolymer include low molecular weight polyols, polyether type polyols, polyester type polyols, castor oil type polyols and the like. These can be used alone or as a mixture of two or more kinds. The low molecular weight polyol is divalent, for example, ethylene glycol, diethylene glycol, propylene glycol,
1,4-butanediol, 1,6-hexanediol,
Neopentyl glycol, hydrogenated bisphenol A, etc. 3
Those having a valence of 3 or more (three to eight valents), for example, glycerin, trimethylolpropane, hexanetriol, pentaerythritol, sorbitol, sucrose and the like can be mentioned. The equivalent of the low molecular weight polyol is 30 to 200.

As the polyether polyol, alkylene oxide (having 2 to 4 carbon atoms) of the above-mentioned low molecular weight polyol is used.
Alkylene oxides of ethylene oxide, propylene oxide, butylene oxide) and ring-opening polymerization products of alkylene oxides, and specifically include polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. The equivalent weight of the polyether polyol is 200 to 1500.

Examples of polyester polyols include polyester polyols, polycaprolactone polyols and polyether ester polyols. Polyester polyols include carboxylic acids (aliphatic saturated or unsaturated carboxylic acids such as adipic acid, azelaic acid, dodecanoic acid, maleic acid, fumaric acid, itaconic acid, dimerized linoleic acid and / or aromatic polycarboxylic acids such as phthalic acid. , Isophthalic acid) and a polyol (the above-mentioned low molecular weight polyol and / or polyether polyol) can be obtained by condensation polymerization.

Polycaprolactone polyol is a polymerization initiator for glycols and triols, and is used as an initiator for ε-caprolactone, α-methyl-ε-caprolactone and ε-methyl-.
It can be obtained by addition polymerization of ε-caprolactone and the like in the presence of an organometallic compound, a metal chelate compound, a fatty acid metal acylated product and the like. The polyether ester polyol is a polyester having a carboxyl group and / or an OH group at the terminal, and an alkyleneoxy group such as ethylene oxide,
It is obtained by addition reaction of propylene oxide and the like. The equivalent weight of the polyester polyol is 200 to 1500.

Examples of castor oil-based polyols include transesterification of castor oil and castor oil or castor oil fatty acid with the aforementioned low molecular weight polyols, polyether polyols and polyester polyols, or esterified polyols. Castor oil-based polyol equivalent is 200
~ 1500 are used.

Among these polyols, preferred are low molecular weight polyols such as 1,4-butanediol and diethylene glycol, polyether polyols such as polyethylene glycol and polypropylene glycol, and amino alcohol polyols such as tetrakishydroxyethyl. Examples thereof include ethylenediamine, tetrakishydroxypropylethylenediamine and castor oil-based polyol.

The equivalent ratio of NCO group / active hydrogen group for obtaining the NCO group-terminated prepolymer of the present invention is 7.0-18.
It is 0. The reaction can be carried out by a urethanization reaction which is usually performed.

Modified product (A) from HDI in the present invention
And NCO group-terminated prepolymer (B) are 5: 95-9
It can be used within the range of 5: 5 (weight ratio).

Curing agents that can be used in the present invention include
It is an amine-based polyol (C) and / or a non-amine-based polyol (D). As the amine-based polyol (C), an oxyalkylated derivative of an amino compound having two or more active hydrogen atoms can be used. As a concrete example, N, N, N ′, N′-tetrakis [2-hydroxypropyl] ethylenediamine as an amino alcohol,
Propylene oxide (PO) or ethylene oxide adducts with amino compounds such as ethylenediamine such as N, N, N ', N'-tetrakis [2-hydroxyethyl] ethylenediamine, or mono-, di-, tri-
Examples include ethanolamine and the like. As the amine-based polyol, those obtained by adding propylene oxide or ethylene oxide to ethylenediamine such as N, N, N ′, N′-tetrakis [2-hydroxypropyl] ethylenediamine are preferable.

Examples of the polyol (D) other than the amine-based polyol as the curing agent include low-molecular polyols, polyether polyols, castor oil-based polyols, polyester-based polyols and the like. As these, the compound having an active hydrogen group used for obtaining the isocyanate group-terminated prepolymer can be used.

The amine-based polyol (C) as the curing agent and the non-amine-based polyol (D) are preferably in the range of 10:90 to 100: 0 (weight ratio).
In this case, when the amount of the amine-based polyol is 10% by weight or less, the curing time becomes long, which is not preferable in consideration of workability and productivity. These curing agents can be used in appropriate amounts by mixing with other polyols depending on the properties required of the binding agent and the sealing agent.

The reaction between the polyisocyanate of the present invention and the curing agent is carried out at an isocyanate group / active hydrogen group equivalent ratio of 0.8.
˜1.6, preferably 0.9 to 1.2. If it deviates from the range of 0.8 to 1.6, the resin may not be cured or the physical properties of the resin may not be exhibited.

The polyurethane elastomer of the present invention is
Especially, since polyisocyanate and curing agent (active hydrogen-containing compound) are liquid at low temperature and have low viscosity and show good curability without using metal or amine-based catalyst, no heating device is required. In addition, polyurethane with high elasticity and physical properties can be used by operating at room temperature and curing at room temperature. further,
It is useful in terms of workability that it contains no unreacted metal or amine-based catalyst, that it does not elute into water or body fluid, and that it has a low temperature liquid state and low viscosity.
Particularly, it shows excellent performances in heat resistance, tensile strength, tear strength, etc. When the eluate is measured with a dialysis type artificial kidney device, the absorbance of the eluate is low and excellent performance is exhibited.

The polyurethane elastomer of the present invention is
Since it is excellent in various physical properties as its attributes, such as hardness, tensile strength, elongation, tear strength, etc., it can be used for various industrial sealing materials, such as electrical, automobile, construction, civil engineering. It can be used as a sealing material or cushioning material for industrial applications such as paper making, iron making, printing, paper feed rolls, and cleaning blades.

The polyurethane elastomer of the present invention does not contain a metal or amine catalyst which is an unreacted material, in addition to the above-mentioned excellent physical properties. Therefore, it is advantageous as a hollow fiber binding material for medical and industrial fluid separation devices using the hollow fiber separation membrane. Examples of these medical and industrial fluid separation devices include plasma separators, artificial lungs, artificial kidneys, artificial livers, and domestic / industrial water treatment devices.

[0028]

EXAMPLES The present invention will be described more specifically below with reference to Examples and Comparative Examples. However, the present invention is not limited to these. All "parts" and "%" in Examples and Comparative Examples are "parts by weight" and "% by weight" unless otherwise specified.

Production of modified HDI (A) Production of A-1 300 parts of HDI in a 500 ml separable flask equipped with a thermometer, a stirrer and a nitrogen seal tube, 1, as a polyol
2.4 parts of 3-BD was added, the air in the flask was replaced with nitrogen, the mixture was heated to a reaction temperature of 80 ° C. with stirring, reacted at the same temperature for 2 hours, and the NCO content was measured to be 48.8%. It was Next, potassium caprate 0.06 as a catalyst
Parts and 0.3 parts of phenol as a cocatalyst were added, and an isocyanurate-forming reaction was carried out at 60 ° C. for 4.5 hours. To this reaction solution, 0.042 parts of phosphoric acid was added as a terminating agent, and the mixture was stirred at the reaction temperature for 1 hour, and then free HDI was removed by a molecular distillation apparatus. The obtained liquid is a pale yellow transparent liquid and has an NCO content of 2
1.0%, viscosity 2200 mPa · s / 25 ° C, free HD
The I content was 0.4%. This modified product is designated as A-1.

Production of A-2 Using the same equipment as in A-1, 300 parts of HDI, 1,3
The reaction was carried out in the same manner as in A-1, using 10.2 parts of BD, 0.06 parts of potassium propionate as a catalyst, 0.3 parts of phenol, and 0.072 parts of phosphoric acid. After reacting HDI with a polyol, the NCO content was 45.3%. After distillation, NCO content 19.2%, viscosity 2800 mPa · s /
The free HDI content was 0.3% at 25 ° C. This modified product is designated as A-2.

Production of A-3 Using the same equipment as in A-2, 300 parts of HDI, 1,6
-HD 3.3 parts, sodium undecylate 0.03 parts,
The reaction was performed in the same manner as in A-1 using 0.198 parts of phosphoric acid. After the HDI was reacted with the polyol, the NCO content was 48.
It was 6%. After distillation, NCO content 20.5%, viscosity 3000 mPa · s / 25 ° C, free HDI content 0.4%
Met. This modified product is designated as A-3.

HDI 30 was prepared using a device similar to A-3.
0 part and 80 parts of trimethylolpropane were reacted at 80 ° C. for 5 hours to give an NCO content of 19.4% and a viscosity of 80,000.
A prepolymer having mPa · s / 25 ° C. was obtained. This prepolymer is designated as A-4.

Production of Isocyanate-Terminated Prepolymer (B) Production of B-1 MDI (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name Millionate MT) 318 using the same apparatus as in the production of modified product (A).
And 15 parts of diethylene glycol were reacted at 80 ° C. for 4 hours to give an NCO content of 28. %, A prepolymer having a viscosity of 80 mPa · s was obtained. This prepolymer is designated as B-1.

Preparation of B-2 Carbodiimide-modified MDI was prepared using the same equipment as in B-1.
(Nippon Polyurethane Industry, trade name Millionate MT
L) 233 parts and PPG-2000 (Asahi Denka Kogyo polyether) 115 parts were reacted at 80 ° C. for 4 hours to obtain NCO.
A prepolymer having a content of 18.0% and a viscosity of 800 mPa · s / 25 ° C. was obtained. This prepolymer is designated as B-2.

Examples 1 to 8 and Comparative Examples 1 to 3 were mixed in the proportions shown in Table 1 to prepare polyisocyanates. The composition for elastomer is shown in Table 1. The above polyisocyanate and the curing agent were mixed at a resin temperature of 25 ° C. so that the reaction equivalent ratio was 0.95, and cured at 25 ° C. The polyisocyanate curing agent quickly became compatible with each other, the gelation time was good, and smooth casting and molding were possible. The hardness, tensile strength, elongation and tear strength of the produced polyurethane are shown in Table 2. Hardness is 2 to check heat resistance
Measured at 5 ° C and 120 ° C.

Dissolution Test Using the compositions of Examples 1-8 and Comparative Examples 1-3, the composition is poured into a mold in which hollow fibers containing about 70% by weight of glycerin are set. After the injection, the adhesive molding was completely performed by the centrifugal molding method. The molded hollow bonded portion is left at 25 ° C. for 7 days for complete curing. After that, it is cut into about 1 cm square and 40 g is used as a test piece. The test results are shown in Table 2. Test item and method Dialysis type artificial kidney device standard
No. V-4, the eluate was measured by an absorptiometry according to the elution test (Note-1) of the bonded portion of the hollow fiber. The measurement wavelength was expanded to 300 to 22 nm for measurement. Note 1: Content of dialysis-type artificial kidney device V-4 Contents Dissolution test of hollow fiber adhesive part For a hollow fiber type dialyzer, cut out the hollow fiber adhesive part for one dialyzer and measure about 1 cm square. Shred into 200 ml of water is added thereto, and the mixture is gently shaken at 40 ° C. for 2 hours and heated. After cooling, take 1.0 ml of the supernatant and add water to make exactly 5.0 ml. When this solution is used as a test solution and water is used as a control and the absorbance at a wavelength of 280 to 240 mm at a layer length of 10 mm is measured by the Japanese absorbance measurement method, the absorbance must be 0.05 or less.

[0037]

[Table 1]

[0038]

[Table 2]

Examples 9 to 16 and Comparative Examples 4 and 5 The same operations as in Examples 1 to 8 and Comparative Examples 4 and 5 were carried out. Details are shown in Tables 3 and 4. The dissolution test was also conducted in the same manner. Table 4
Shown in.

[0040]

[Table 3]

[0041]

[Table 4]

Claims (1)

[Claims] 1. A polyurethane elastomer composition comprising a polyisocyanate and a curing agent, wherein the polyisocyanate is NC of hexamethylene diisocyanate.
It is composed of a modified product (A) in which a part of O groups is converted to a polyol adduct and then isocyanurate, and an NCO group-terminated prepolymer (B), and as the curing agent, an amine polyol (C) and / or an amine system A composition for polyurethane-based elastomers, which comprises a polyol (D) other than the above.