JP3341266B2 - Method for producing polyurethane-based elastomer-forming composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a polyurethane-based elastomer-forming composition. More specifically, the present invention relates to a method for producing a polyurethane-based elastomer-forming composition used for a polyurethane-based sealing agent, a binding agent, and the like.
It is about .

[0002]

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

[0003] 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 (TDI) as a main agent (polyisocyanate). Aromatic isocyanates such as MDI) or hexamethylene diisocyanate (H
DI), hydrogenated MDI, isophorone diisocyanate (I
A prepolymer prepared 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 the hydrogen-containing compound), castor oil-based polyols such as castor oil and alcohol-modified castor oil, and polypropylene glycol, polyethylene glycol and the like are used.

[0004] In these sealants and binders, low-viscosity systems that cure quickly at low temperatures have been studied, and problems in workability and moldability are decreasing. However, in terms of physical properties, it is low in elasticity, strength and the like, and is inferior in durability.

On the other hand, in the case of two-component polyurethane for OA equipment parts such as industrial rolls for papermaking, ironmaking and printing, paper feed rolls, cleaning blades and the like, the 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. As a curing agent (active hydrogen-containing compound), 4,4′-methinebis (2- Chloroaniline), an aromatic amine such as 4,4'-methylenedianiline, or an aliphatic glycol such as 1,4-butanediol and trimethylolpropane to obtain a resin having high elasticity and high physical properties. Is widely used in industrial fields There.

[0006] However, these systems have low reactivity at low temperatures and require heat curing at 100 ° C or higher to obtain high physical properties. Furthermore, 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 a low temperature, addition of a heavy metal catalyst such as Sn, Pb, Zn or Cd or an amine catalyst such as triethylenediamine or triethylamine is also performed. In addition to the possibility of instability, there are problems in medical applications, such as elution into body fluids and adverse effects on living organisms. Further, conventional resins have disadvantages such as high altitude and brittleness, and improvement thereof is demanded.

[0008]

SUMMARY OF THE INVENTION In order to obtain the disadvantages of the conventional polyurethane-based sealants and binders, that is, high elasticity, high physical properties, quick reactivity and good productivity, the present invention requires the viscosity of the resin. In the case of high curing, heat curing is required, and on the contrary, those that cure quickly at low temperatures have limited physical properties and their applications are limited, and furthermore, the dissolution rate is high and there is no biocompatibility, and the hardness of the resin Is too high to improve brittleness and the like.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies and studies to improve the conventional disadvantages. As a result, the present inventors have obtained a reaction as a polyisocyanate in the presence of HDI, a polyol and a trimerization catalyst. Modified isocyanurate (A) and diphenylmethane diisocyanate (MD
The present invention was found to be able to be improved by using the prepolymer ( I) or the NCO group-terminated prepolymer of the carbodiimide-modified MDI in combination (B).

That is, the present invention provides a process for producing a polyurethane elastomer-forming composition comprising a polyisocyanate and a curing agent, wherein the polyisocyanate is hexamethylene diisocyanate, a polyol having a molecular weight of 62 to 3,000 and a functional group of 2 to 3 ( E) and an isocyanurate-modified hexamethylene diisocyanate (A) having a urethane bond and an isocyanurate ring structure obtained by simultaneously performing a urethanization reaction and a trimerization reaction in the presence of a trimerization catalyst, and diphenylmethane diisocyanate (M
DI) or an NCO group-terminated prepolymer of carbodiimide-modified MDI (B), and is obtained by mixing the amine-based polyol (C) and / or the non-amine-based polyol (D) as the curing agent. The present invention relates to a method for producing a polyurethane-based elastomer-forming composition.

[0011]

The polyisocyanate usable in the present invention is a modified isocyanurate of HDI having a urethane bond and an isocyanurate ring structure in a molecule obtained by reacting in the presence of HDI, polyol (E) and a catalyst. [hereinafter modified product of HDI as (a)], and diphenyl
Methane diisocyanate (MDI) or carbodiimi
And the NCO-terminated prepolymer of modified MDI (B). In the modified HDI (A), a part (15% by weight or less) of all NCO groups before the reaction of HDI has a urethane bond. As the polyol (E) having a molecular weight of 62 to 3000 and a number of functional groups of 2 to 3 for obtaining the HDI modified product (A), bifunctional polyols include, for example, ethylene glycol, diethylene glycol (DEG),
1,3-butanediol (1,3-BD), 1,4-butanediol (1,4-BD), propylene glycol, dipropylene glycol (DPG), neopentyl glycol (NPG), 1,6-hexane Examples thereof include diols such as diol (1,6-HD), divalent polyester polyols, and polyether polyols. Trifunctional polyols include, for example, glycerin, trimethylolethane, and trimethylolpropane (TMP).
And trivalent polyether polyols. Furthermore, a bifunctional or more functional polyester polyol is mentioned. These polyols can be used alone or as a mixture of two or more. The preferred molecular weight of these polyols is from 62 to 2000.

The urethane bond in the modified HDI (A) is not more than 15% by weight of all isocyanate groups before the start of the reaction. If the content is 15% by weight or more, the characteristics of the isocyanurate ring structure formed thereafter cannot be sufficiently exhibited. It is preferably at most 10% by weight.

The trimerization catalyst (hereinafter abbreviated as catalyst) used for obtaining the modified form (A) of HDI is represented by a general formula:
A potassium or sodium salt of an organic acid represented by C _n H _{2n + 1} COOH, which can be used alone or in combination with a co-catalyst, if necessary, at 100 ° C. or lower. Catalysts that can be used include propionic acid, butyric acid,
Valeric acid, caproic acid, heptanoic acid, caprylic acid, pelargonic acid, capric acid, undecylic acid and potassium or sodium salts of these branched fatty acids.

When a phenolic hydroxy compound or an alcoholic hydroxy compound is used as a co-catalyst simultaneously with these catalysts, the reaction proceeds more easily. H like this
The progress of the urethanization and isocyanuration reaction of DI can be known by measuring the NCO content during the reaction. The NCO content of the modified HDI (A) is 16.5 to 23.5% by weight.

[0016] Used in the polyisocyanate of the present invention
Diphenylmethane diisocyanate (MDI) or cal
The NCO group-terminated prepolymer (B) of the bodiimide-modified MDI is obtained by reacting an NCO group with an active hydrogen group. MDI having an NCO group or a part of MDI is converted to biuret, allophanate, carbodiimide,
Those modified with oxazolidone, amide, imide or the like are used.

Examples of the compound having an active hydrogen group for obtaining a prepolymer include low molecular polyols, polyether polyols, polyester polyols, amine polyols, castor oil polyols and the like. These can be used alone or as a mixture of two or more. Examples of the low molecular polyol include divalent ones such as ethylene glycol, DEG, propylene glycol, 1,4-BD, 1,6-HD, DPG, NPG, hydrogenated bisphenol A, and the like. Octavalent) such as glycerin, TMP, hexanetriol,
Pentaerythritol, sorbitol, puffer rose and the like. The molecular weight of the low molecular polyol is from 62 to 5.
00 is used.

As the polyether polyol, alkylene oxides of the above-mentioned low molecular polyols (C 2-4)
Alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide) and ring-opened polymers of alkylene oxides, and specifically include polyethylene glycol, polypropylene glycol and polytetramethylene ether glycol. A polyether polyol having a molecular weight of 400 to 3000 is used. Preferably, it is 500 to 2500.

Examples of the polyester polyol include polyester polyol, polycaprolactone polyol, and polyetherester polyol. 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 low-molecular polyol and / or polyether polyol). The molecular weight of such polyols is between 400 and 5000. Preferably 500-300
0.

Polycaprolactone polyols include ε-caprolactone, α-methyl-ε-caprolactone, and ε-methyl-polymerization initiators such as glycols and triols.
It can be obtained by addition polymerization of ε-caprolactone and the like in the presence of an organic metal compound, a metal chelate compound, a fatty acid metal acylate and the like. The molecular weight of such a lactone polyol is 400-3000. The polyetherester polyol is obtained by subjecting a polyester having a terminal carboxyl group and / or OH group to an addition reaction with an alkyleneoxy group such as ethylene oxide or propylene oxide. The equivalent of the polyester polyol is 200 to
1500.

Examples of the amine polyol include tetrakishydroxyethylethylenediamine and tetrakishydroxypropylethylenediamine.

Examples of castor oil-based polyols include transesterification of castor oil and castor oil or castor oil fatty acid with the low-molecular-weight polyols, polyether polyols and polyester polyols, or esterified polyols. Castor oil-based polyol has a molecular weight of 50
Those having a size of 0 to 3000 are used. Preferably molecular weight 8
00 to 2000.

Preferred among these polyols are low molecular weight polyols such as 1,4-BD and DE.
G, DPG, tripropylene glycol, polyether-based polyols include polyethylene glycol and polypropylene glycol, and aminoalcohol-based polyols include tetrakishydroxyethylethylenediamine, tetrakishydroxypropylethylenediamine, and castor oil-based polyol. In this case, if the isocyanate is solid at room temperature, it can be made into a stable pre-polymer that is liquid at room temperature and is easy to handle by using a propylene glycol as a prepolymer.

The diphenylmethane diisocyanate of the present invention
The equivalent ratio of NCO groups / active hydrogen groups for obtaining the NCO group-terminated prepolymer (B) of carbodiimide or carbodiimide-modified MDI is 7.0 to 18.0. The reaction can be performed at a temperature of 30 to 120 ° C. for a reaction time of 3 to 8 hours. The polyisocyanate of the present invention comprises a modified form of HDI (A) and diphenylmethane diisocyanate (MD
I) or the NCO group-terminated prepolymer of carbodiimide-modified MDI (B) can be used in the range of 5:95 to 95: 5 (weight ratio). Preferably, 15:85
８５85: 15 (weight ratio).

The curing agent that can be used in the present invention is:
It is an amine-based polyol (C). As the amine-based polyol (C), an oxyalkylated derivative of an amino compound having two or more active hydrogen atoms can be used. As specific examples, N, N, N ′,
Propylene oxide (PO) to amino compounds such as ethylenediamine such as N'-tetrakis [2-hydroxypropyl] ethylenediamine, N, N, N ', N'-tetrakis [2-hydroxyethyl] ethylenediamine
Alternatively, an ethylene oxide adduct, or mono-, di-, or tri-ethanolamine may, for example, be mentioned. The amine-based polyol is N, N, N ', N'-tetrakis [2-
[Hydroxypyrrol] ethylenediamine and the like to which propylene oxide and ethylene oxide are added are preferable.

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

The amine-based polyol (C) and the non-amine-based polyol (D) as such a curing agent preferably have a weight ratio of 10:90 to 100: 0.
In this case, if the content of the amine-based polyol is 10% by weight or less, the curing time is prolonged, which is not preferable in view of workability and productivity. These curing agents can be used by mixing them with other polyols in appropriate amounts according to the required properties of the binder and the sealant.

The reaction between the polyisocyanate of the present invention and the curing agent is carried out by an isocyanate group / active hydrogen group equivalent ratio of 0.8.
To 1.6, preferably in the range of 0.9 to 1.2. If the ratio is out of 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.

In the method for producing a polyurethane elastomer-forming composition of the present invention, in particular, a polyisocyanate and a curing agent (active hydrogen-containing compound) have a low-temperature liquid and low viscosity and use a metal or amine catalyst. Without
Since it shows good curability, polyurethane having high elasticity and high physical properties can be used by operating at room temperature and curing at room temperature without requiring a heating device. Further, the absence of unreacted metals or amine catalysts means that there is no elution into water or body fluids, and low-temperature liquidity and low viscosity are useful in terms of workability. In particular, it shows excellent performance in heat resistance, tensile strength, tear strength and the like, and when eluate is measured in a dialysis-type artificial kidney device, the absorbance of the eluate is low and shows excellent performance.

The method for producing a polyurethane elastomer-forming composition of the present invention is excellent in various physical properties such as hardness, tensile strength, elongation, and tear strength. For various industrial seal materials, for example, electrical, automotive, architectural and civil engineering seal materials or various cushioning materials, as well as OA equipment parts such as industrial rolls for papermaking, steelmaking, printing, paper feed rolls, cleaning blades, etc. Available.

The process for producing the polyurethane elastomer-forming composition of the present invention does not contain a metal or an amine catalyst which is an unreacted product, in addition to the above-mentioned excellent physical properties.
Therefore, it is advantageous as a hollow fiber binding agent for medical and industrial fluid separation devices using a hollow fiber separation membrane. Examples of these medical and industrial fluid separators include a plasma separator, an artificial lung, an artificial kidney, an artificial liver, and a domestic / industrial water treatment apparatus.

[0032]

[0033]

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. "Part" in Examples and Comparative Examples
And “%” are all “parts by weight” unless otherwise specified,
"% By weight".

Preparation of Modified Form of HDI (A) Preparation of A-1 300 parts of HDI in a 500 ml separable flask equipped with a thermometer, stirrer and nitrogen sealed tube, 2.7 parts of 1,3-BD as polyol (E), 0.06 parts of potassium caprate as a catalyst and 0.3 parts of phenol as a co-catalyst were added, the air in the flask was replaced with nitrogen, and the mixture was heated to a reaction temperature of 70 ° C. with stirring, and reacted at the same temperature for 4 hours. went.
0.042 parts of phosphoric acid was added to this reaction solution as a terminator,
After stirring for 1 hour at the reaction temperature, free HD
I was removed. The obtained liquid is a pale yellow transparent liquid with NCO
The content was 20.7%, the viscosity was 2200 mPa · s / 25 ° C., and the free HDI content was 0.3%. This modified product is designated as A-1.

Production of A-2 300 parts of HDI, 1,3-
BD 10.2 parts, potassium propionate 0.1 as a catalyst.
The reaction was carried out in the same manner as in A-1, using 06 parts, 0.3 parts of phenol and 0.072 parts of phosphoric acid. After distillation, the NCO content was 19.1%, the viscosity was 2800 mPa · s / 25 ° C., and the free H
The DI content was 0.3%. This modified product is designated as A-2.

Production of A-3 300 parts of HDI, 1,6-
The reaction was carried out in the same manner as in A-2 using 3.3 parts of HD, 0.03 parts of sodium undecylate and 0.198 parts of phosphoric acid. After distillation, NCO content 20.3%, viscosity 3000m
Pa · s / 25 ° C., free HDI content 0.2%.
This modified product is designated as A-3.

Production of A-4 (Comparative Example) Using an apparatus similar to A-3, 300 parts of HDI and 60 parts of trimethylolpropane were reacted at 80 ° C. for 5 hours to obtain N.
CO content 26.0%, viscosity 70,000 mPa · s / 2
A prepolymer at 5 ° C. was obtained. This prepolymer was designated as A-4
And

Preparation of NCO-terminated prepolymer (B) Preparation of B-1 Preparation of modified product MDI was carried out using the same apparatus as in (A-1).
(Millionate MT, manufactured by Nippon Polyurethane Industry)
318 parts and 15 parts of diethylene glycol at 80 ° C.
After reacting for 2 hours, the NCO content is 28.0% and the viscosity is 80 mPa.
-The prepolymer of s was obtained. This prepolymer is referred to as B-1
And

Preparation of B-2 Using the same apparatus as in B-1, carbodiimide-modified MDI
(Millionate MT, manufactured by Nippon Polyurethane Industry
L) 233 parts and 110 parts of PPG-2000 (polyether manufactured by Asahi Denka Kogyo) were reacted at 80 ° C. for 4 hours to obtain NCO.
A prepolymer having a content of 18.2% and a viscosity of 750 mPa · s / 25 ° C. was obtained. This prepolymer is referred to as B-2.

Production of B-3 320 parts of MDI (Millionate MT, manufactured by Nippon Polyurethane Industry Co., Ltd.) and 1,3-
10 parts of BD and 20 parts of dipropylene glycol were reacted at 80 ° C. for 4 hours to obtain an NCO content of 24.3% and a viscosity of 180 m.
A prepolymer having a Pa · s / 25 ° C. was obtained. This prepolymer is designated as B-3.

Examples 1 to 8 and Comparative Examples 1 to 4 Polyisocyanates were prepared by mixing at the ratios shown in Table 1. Table 1 shows the composition of the elastomer-forming composition. The amounts used in the table are parts. The above polyisocyanate and the curing agent are reacted at a resin temperature of 25 ° C. with a reaction equivalent ratio of 0.1.
95 and cured at 25 ° C. The polyisocyanate curing agent was quickly made compatible and uniform, had a good gelation time, and was capable of smooth casting and molding. Table 2 shows the hardness, tensile strength, elongation and tear strength of the produced polyurethane. Hardness is 25 ℃ and 1 to check heat resistance
It was measured at 20 ° C.

Dissolution Test Using the compositions of Examples 1 to 8 and Comparative Examples 1 to 3, a hollow fiber containing about 70% by weight of glycerin is poured into a set mold. After the injection, the adhesive was completely molded by a centrifugal molding method. The molded hollow adhesive portion is left at 25 ° C. for 7 days to perform complete curing. Then cut into 1cm squares and 40g
Is a test piece. Table 2 shows the test results. Test items and methods Dialysis-type artificial kidney device standard (Notice 494 by the Director of Pharmaceutical Affairs Bureau, Ministry of Health and Welfare)
No.) The eluate was measured by an absorption measurement method in accordance with the elution test (Note-1) of the V-4 hollow fiber adhesion portion. The measurement wavelength was expanded to 300 to 22 nm. Note-1: Dialysis type artificial kidney device standard V-4 content Dissolution test of hollow fiber adhesive part For hollow fiber type dialyzer, one hollow fiber adhesive part of one dialyzer was cut out, and the size was about 1 cm square. Shred into pieces. 200 ml of water is added thereto, and the mixture is gently shaken and heated at 40 ° C. for 2 hours. 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, the absorbance at a wavelength of 280 to 240 mm with a layer length of 10 mm is measured by the absorbance measurement method of the Japanese Pharmacopoeia. The absorbance must be 0.05 or less.

[0043]

[Table 1]

[0044]

[Table 2]

Examples 9 to 16 and Comparative Examples 4 and 5 The same operation as in Examples 1 to 8 and Comparative Examples 1 to 3 was carried out. The compositions and physical properties are shown in Tables 3 and 4. The dissolution test was performed similarly. It is shown in Table 4.

[0046]

[Table 3]

[0047]

[Table 4]

Examples 17 to 24 The same procedures as in Examples 1 to 8 were carried out. Details are shown in Tables 5 and 6. The dissolution test was performed similarly. It is shown in Table 6.

[0049]

[Table 5]

[0050]

[Table 6]

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-319007 (JP, A) JP-A 64-2653 (JP, A) JP-A 64-38102 (JP, A) 157708 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C08G 18/00-18/87

Claims (1)

(57) [Claims] 1. A process for producing a polyurethane elastomer-forming composition comprising a polyisocyanate and a curing agent, wherein the polyisocyanate is hexamethylene diisocyanate, a polyol (E) having a molecular weight of 62 to 3,000 and a functional group of 2 to 3, and Isocyanurate-modified hexamethylene diisocyanate (A) having a urethane bond and an isocyanurate ring structure obtained by simultaneously performing a urethanation reaction and a trimerization reaction in the presence of a quantification catalyst, and a diphenylmethane diisocyanate (MDI) or carbodiimide modification It is obtained by mixing an NCO-terminated prepolymer (B) of MDI with an amine-based polyol (C) and / or a non-amine-based polyol (D) as the curing agent. Polyurethane elastomer type Method for manufacturing a sexual composition.