JPH1060071A - Two pack type polyurethane elastomer composition for casting and production of polyurethane elastomer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of preventing an elastomer from changes in physical characteristics caused by a gap between stoichiometric amounts and also exhibiting an excellent casting work efficiency and physical strength by using a specific prepolymer having isocyanate terminals and a polyol. SOLUTION: This two pack type polyurethane elastomer composition for casting consists of a mixture of (A) a prepolymer having isocyanate terminals and (B) a mixture of (B1 ) a long chain polyol with a short chain diol and a short chain triol, and diphenylmethane diisocyanate containing an isomer thereof, a dimerized compound, or carbodiimide-modified material and a hexamethylenediisocyanate-modified material containing an isocyanulate ring or the ring with an urethodione ring, is used as the polyisocyanate for the component (A), and also a polycarbonate polyol and a polycaprolactone polyol are used simultaneously, or a poly(carbonate/caprolactone) polyol is used as the polyol for the component (A) and for the component (B1 ).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a two-component polyurethane elastomer composition for casting. More specifically, NC from specific polyisocyanate and specific polyol
Polyurethane elastomer composition for two-pack casting comprising O-group-terminated prepolymer and long-chain polyol, short-chain diol, short-chain triol, etc., and a process for producing polyurethane elastomer having excellent workability and physical strength of the composition It is about.

[0002]

2. Description of the Related Art Conventionally, molding techniques of cast urethane elastomers are generally classified into two types, one-shot method and prepolymer method. The one-shot method is a method in which all the raw materials are mixed and stirred in a reactor at a time, then cast, the reaction is almost completed by primary cure, the mold is released, and then the secondary cure is performed. So is the most economical way. However, since a polymerization reaction such as urethanization proceeds at a time, a large amount of heat is generated, and it is difficult to obtain stable physical characteristics. On the other hand, the prepolymer method employs a two-step method including a step of preliminarily reacting a polyol and an excess of isocyanate to synthesize a prepolymer, and a step of reacting the prepolymer with other insufficient raw materials to finally produce an elastomer. In the case of the prepolymer method, most cast urethane elastomers are produced by this method because the heat associated with the urethanization reaction has already been released during the prepolymerization and has the advantages described below. (A) Since the reaction proceeds uniformly, an elastomer having high physical properties can be obtained. (B) The total heat generation is small, and large-sized molding is possible. (C) A segmented polyurethane in which a curing agent such as glycol or amine is freely selected can be produced. However, drawbacks of this prepolymer method include high viscosity and offset of the mixture ratio. If the viscosity is high, poor defoaming, poor mixing with the curing agent, and the like may occur, while if the mixture ratio is uneven, there is a concern that a change in physical properties due to a shift in stoichiometry.

In Japanese Patent Publication No. 3-41833, diphenylmethane diisocyanate, tolylene diisocyanate or the like is used as an organic polyisocyanate, which is reacted with polycaprolactone ester to obtain a prepolymer, and as a curing agent, 1,4-butanediol or Urethane rubber is obtained using diamine. This urethane rubber aims at stability against temperature change, durability against heat, and stability for a long period of time. JP-A-5-24049 discloses a polyurethane molded product obtained by reacting diphenylmethane diisocyanate with polyethylene adipate polyol as a polyisocyanate to obtain a prepolymer, and using polyethylene adipate polyol and 1,4-butanediol as a curing agent. It has gained. The purpose of this elastomer is to reduce distortion without reducing low-temperature properties. JP-A-5-278045 discloses that a polyurethane molded product is obtained by reacting diphenylmethane diisocyanate with polycaprolactone ester diol as a polyisocyanate to obtain a prepolymer, and using a high molecular polyol and a low molecular polyol as a curing agent. ing. The purpose of this elastomer is to obtain abrasion resistance and durability. Tokuhei 7-7222
In JP-A No. 2, a prepolymer is obtained by using diphenylmethane diisocyanate or tolylene diisocyanate as a polyisocyanate and reacting polyoxytetramethylene glycol in the presence of a plasticizer. A polyurethane molded product is obtained by reacting with an amine as a curing agent in the presence of a plasticizer. The purpose of this elastomer is to have good moldability, low hardness, and rubber elasticity.

[0004]

SUMMARY OF THE INVENTION The present inventors have solved the drawbacks of the conventional casting technique, especially the prepolymer method, and have conducted intensive studies and studies on improvement of workability and various physical properties. By using an NCO-terminated prepolymer and a polyol composed of a polyester polyol, etc., the change in physical properties due to the stoichiometric deviation is remarkably improved, and the defoaming property and the demolding time are shortened by lowering the viscosity. As a result, the castability was improved, and the obtained elastomer was found to have excellent physical strength, and reached the present invention.

[0005]

That is, the present invention provides (A)
In a polyurethane elastomer composition comprising a mixture of an NCO-terminated prepolymer as a component and a long-chain polyol, a short-chain diol and a short-chain triol as a component (B), the polyisocyanate of the NCO-terminated prepolymer is diphenylmethane diisocyanate-based polyisocyanate And hexamethylene diisocyanate-based polyisocyanate, wherein the diphenylmethane diisocyanate-based polyisocyanate is diphenylmethane diisocyanate containing diphenylmethane diisocyanate containing isomer-containing diphenylmethane diisocyanate and / or diphenylmethane diisocyanate dimer compound and / or carbodiide-modified diphenylmethane diisocyanate, and hexamethylene Diisocyanate polyisocyanate Comprises a modified isocyanurate ring-containing hexamethylene diisocyanate or a modified uretdione ring and isocyanurate ring-containing hexamethylene diisocyanate. The polyol for the NCO-terminated prepolymer and the long-chain polyol of component (B) , A combination of polycarbonate polyol and polycaprolactone polyol, and / or poly (carbonate.
(2) Caprolactone) a polyol
It is a polyurethane elastomer composition for liquid casting.

According to the present invention, a two-component polyurethane elastomer composition for casting is used to mix the components (A) and (B) with three components.
A method for producing a polyurethane elastomer, comprising mixing and casting at 5 to 95 ° C.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION NCO which is the component (A) of the present invention
Examples of the diphenylmethane diisocyanate (hereinafter abbreviated as MDI) -based polyisocyanate constituting the terminal-terminated prepolymer include isomer-containing MDI, MDI dimer, carbodiided MDI, etc., and polyphenylpolymethylene polyisocyanate (hereinafter abbreviated as polymeric MDI). The isomer-containing MDI includes various isomers of MDI, and includes 4,4′-MDI, 2,4′-MDI, and 2,2′-.
Any mixture such as MDI. Such isocyanates can be used alone or as a mixture of two or more. In addition, derivatives of such isocyanates can be exemplified.

The isomer-containing MDI is 50 to 98% by weight of 4,4'-MDI and 50 to 2% of MDI other than 4,4'-MDI.
%, Preferably 4,4'-MDI of 50 to
90% by weight, 2,2'- and 2,4'-MDI from 50 to
10% by weight. More preferably, 4,4'-MDI is 71 to 86% by weight, and 2,2'- and 2,4'-MDI is 29 to 14% by weight. Among these, the weight ratio of 2,2'-MDI to 2,4'-MDI is 0.2 to 20% by weight of 2,2'-MDI, and 2,4'-MDI is 99.8 to 80.
%, Preferably 2,2′-MDI is 0.5 to
10% by weight, 99.5 to 90% by weight of 2,4'-MDI.

[0009] The MDI dimer used in the present invention is MD
I or an isomer-containing MDI, or a catalyst that promotes dimerization is added to a polyol adduct of MDI or an isomer-containing MDI, and the mixture is reacted at 50 to 90 ° C. for 4 to 9 hours, and a catalyst deactivator is added. Can be obtained by: Examples of the catalyst that promotes dimerization include tri-n-butylphosphine, tri-n-octylphosphine, and tris- (dimethylamino) phosphine. Examples of the catalyst deactivator include methyl p-toluenesulfonate, Diphosphate
(2-ethylhexyl) -ester and the like. The MDI dimer thus obtained has an NCO content of 29.0 to 33.0% by weight, preferably an NCO content of 30.0 to 32.0% by weight.

The carbodiimidated modified M used in the present invention
DI is MDI or isomer-containing MDI, or MDI
Alternatively, as a carbodiimidization catalyst for a polyol adduct of isomer-containing MDI, for example, a phosphorene-based catalyst such as 3-
Methyl-1-phenyl-3-phospholene-1-oxide, 3-methyl-1-ethyl-3-phospholene-1-oxide, 3-methyl-1-phenyl-2-phospholene-1-oxide, 1-methyl -3-phospholene-1
-Oxide, 1-phenyl-2-phospholene-1-oxide, 1-methoxy-3-phospholene-1-toxide, 3-methyl-1-phenyl-3-phospholene-1
-Reaction is carried out at 50 to 90 ° C. for 3 to 5 hours using sulfide or the like, and trichlorosilane, dichloroaphenylsilane, trichloromethylsilane, trichlorovinylsilane, dichlorodimethylsilane, etc. are added as a catalyst deactivator. To complete the reaction. The carbodiimidated modified MDI thus obtained has an NCO content of 28.0 to 32.8% by weight, preferably an NCO content of 29.0 to 32.0% by weight.

MDI or MD containing isomer used in the present invention
The polyol adduct of I is MDI or isomer-containing MDI
And a polyol at a temperature of about 50 to 100 ° C. In this case, not more than 20% by weight of the NCO groups of the MDI or the isomer-containing MDI is reacted with the polyol to obtain a polyol adduct of the MDI or the isomer-containing MDI. The polyol for obtaining a polyol adduct of MDI or an isomer-containing MDI has a molecular weight of 62 to 3
000, having a functionality of 2-3, for example, 1,3-butanediol (hereinafter abbreviated as 1,3-BD), dipropylene glycol, 1,6-hexane glycol (hereinafter, 1,6-BD)
HG), 3-methyl-1,5-pentanediol, neopentyl glycol (hereinafter abbreviated as NPG),
2,2-diethyl-1,3-propanediol, 2-ethyl-1,3-hexanediol, 2-n-butyl-2
-Ethyl-1,3-propanediol (hereinafter referred to as BEPG
Glycerin, trimethylolpropane, etc., polyester polyols obtained by the ester reaction of these diols and triols with dibasic acids, and polyether polyols obtained by the addition reaction of these diols and triols with alkylene oxides And the like. These can be used alone or as a mixture of two or more.

[0012] The present invention relates to a polyisocyanate, MD
Since an I-based polyisocyanate is used, it has good physical properties such as tensile strength, tear strength and abrasion resistance, and has excellent durability. A carbodiimide-modified MDI obtained from a polyol adduct of MDI or an isomer-containing MDI, or MDI
The DI dimer and the carbodiimide-modified MDI have extremely excellent compatibility with the HDI-based polyisocyanate.

The hexamethylene diisocyanate (hereinafter abbreviated as HDI) polyisocyanate constituting the NCO-terminated prepolymer which is the component (A) of the present invention includes:
The most preferred is an isocyanurate ring-containing modified product of HDI or an HDI polyol adduct (hereinafter abbreviated as a nurate modified product), or an uretdione / nurate modified product of HDI or an HDI polyol adduct. In addition, HD
A derivative of I, hydrogenated diphenylmethane diisocyanate,
There are hydrogenated tolylene diisocyanate and the like, which can be used alone or in combination as a mixture of two or more.

[0014] As a catalyst for obtaining a modified HDR of HDI, propionic acid, butyric acid, valeric acid, caproic acid,
Heptanoic acid, caprylic acid, pelargonic acid, capric acid,
Undecylic acid and the potassium or sodium salts of these branched fatty acids. As a co-catalyst that can be used in combination with the catalyst, a phenolic hydroxy compound (phenol, cresol, etc.), an alcoholic hydroxy compound (ethanol, cyclohexanol, etc.), or a tertiary amine (triethylamine, methylpiperidine, etc.) is used. be able to. The reaction proceeds easily with this co-catalyst. The amount of the catalyst used is 0.001 to 0.25% by weight based on the polyisocyanate, and the cocatalyst is 0.01 to 0.2% by weight.
0.2% by weight. In addition, a reaction terminator can be used. As the terminating agent, for example, phosphoric acid, sulfuric acid, methyl p-toluenesulfonate and the like can be used, and the used amount can be 0.5 to 5.0 times the catalyst equivalent.

Examples of effective catalysts for obtaining modified uretdione / nurate derivatives of HDI include phosphines such as triethylphosphine, dibutylethylphosphine, tri-n-propylphosphine, trioctylphosphine and triamylphosphine.

The reaction for obtaining such a modified form of HDR or a modified uretdione / nurate can be obtained by reacting at 50 to 100 ° C. for 3 to 7 hours. The reaction mixture thus obtained can remove unreacted HDI, for example, by thin-film distillation.
The uretdione / nurate modified form of HDI has a ratio of the isocyanurate cyclic trimer content of 11 to 40% by weight to the uretdione dimer content of 20 to 60% by weight.
The NCO group content is 17 to 25% by weight.

The polyol adduct of HDI used in the present invention is one in which a part (20% by weight or less) of all NCO groups is a polyol adduct. As the polyol that can be used here, the polyol used when obtaining the MDI polyol adduct can be used. The uretdione dimer content and isocyanurate cyclic trimer content were determined from a calibration curve based on the area percentage of each peak obtained by gel permeation chromatography using differential refractometer detection.

The MDI-based polyisocyanate constituting the NCO-terminated prepolymer which is the component (A) of the present invention and H
The weight ratio of the DI polyisocyanate to be used is 70 to 95 parts for the MDI system and 30 to 5 parts for the HDI system, preferably 75 to 90 parts for the MDI system and 2 for the HDI system.
5 to 10 parts.

The polyol constituting the NCO-terminated prepolymer which is the component (A) of the present invention may be a combination of a polycarbonate polyol and a polycaprolactone polyol, and / or poly (carbonate / caprolactone).
There are polyols. Polycarbonate polyols having a molecular weight of 500 to 4000, for example, a dealcoholization condensation reaction of glycols and dialkyl carbonates such as dimethyl and diethyl, or a phenol condensation reaction of glycols and diphenyl carbonate, or glycols and ethylene carbonate, diethyl carbonate and the like And those obtained by the ethylene glycol condensation reaction. As the glycols, for example,
1,6-HG, diethylene glycol, propylene glycol, 1,4-butanediol, 3-methyl-1,5
-Aliphatic diols such as pentanediol and NPG; and alicyclic diols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol. For example, there is poly (hexamethylene carbonate) polyol obtained by a condensation reaction between 1,6-HG and diethyl carbonate.

The polycaprolactone polyol used in the present invention has a molecular weight of 500 to 4000, for example, α
Lactones such as caprolactone, β-caprolactone, γ-caprolactone, δ-caprolactone, α-methyl-ε-caprolactone, β-methyl-ε-caprolactone and ethylene glycol, propylene glycol, 1,4-butanediol, 5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-
It can be obtained by reaction with HG, NPG, diethylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, decamethylene glycol, polyethylene glycol, polytetramethylene glycol and the like. Preferred molecular weights are between 1000 and 3000. For example, specifically, Praxel P-210 (molecular weight: 1000) and Praxel P-22 manufactured by Daicel Chemical Industries, Ltd.
0 (molecular weight 2000), TONE POLYO made by UNION CARBIDE
L 0210 (molecular weight 530, hydroxyl value 212), TONE POLYO
L 0210 (molecular weight: 830, hydroxyl value: 135). Further, as a triol, TONE POLYOL 0305 (molecular weight 54
0, hydroxyl value 310), TONE POLYOL 0301 (molecular weight 30)
0, hydroxyl value 560), TONE POLYOL 0310 (molecular weight 90
0, hydroxyl value 187) and the like.

Further, a lactone-based polyester polyether polyol can also be used. This can be obtained by conducting a ring-opening addition polymerization reaction of a lactone with a polyol having two or more active hydrogen groups in the presence of a catalyst, followed by adding an alkylene oxide in the presence of a catalyst to carry out the reaction. As the polyol or lactone, the compound used for obtaining polycaprolactone polyol can be used. Examples of the catalyst include alkali metals such as lithium, sodium, and potassium, and hydroxides and alcoholates thereof, and these can be used alone or as a mixture of two or more.

The poly (carbonate / caprolactone) polyol used in the present invention may have a molecular weight of 500-4.
000, a method of transesterifying a polycarbonate polyol with a polycaprolactone polyol, or a method of reacting a polycarbonate polyol with a lactone, the polycarbonate polyol and the polycaprolactone) polyol and the lactone and / or the carbonate. It can be obtained by a method or the like by reacting in the presence of a compound. The usage ratio of the polycarbonate polyol and the polycaprolactone polyol used in the present invention is 25 to 75% by weight of the polycarbonate polyol and 75 to 25% by weight of the polycaprolactone polyol. By the use of such various polyols,
Elastomers have hydrolysis resistance, tensile strength, tear strength,
It has excellent durability such as abrasion resistance.

The preparation of the NCO group-terminated prepolymer as the component (A) of the present invention is carried out at a molar ratio of NCO group / active hydrogen group in the range of 3.0 to 30, preferably 4.0 to 20. Will be The reaction between the polyisocyanate and the polyol may be carried out according to a conventional method. The reaction is usually carried out at a temperature of 50 to 100 ° C. to obtain an NCO-terminated prepolymer.

As the component (B) of the present invention, a long-chain polyol, a short-chain diol, a short-chain triol and the like are used.
As the long-chain polyol, a polyol having a molecular weight of 500 to 4000 used for obtaining an NCO group-terminated prepolymer is used.

The short-chain diol used in the component (B) of the present invention includes, for example, ethylene glycol, propanediol, butanediol, pentanediol, 1,6-HG, methylpentanediol, NPG, and the like having a molecular weight of 62 to less than 500. Cyclohexanedimethanol, 1,4-bis (2-hydroxyethoxy) benzene (hereinafter referred to as BHE
B), diethylene glycol, dipropylene glycol and the like. Preferred molecular weights are from 62 to 25.
0.

The short-chain triol used in the component (B) of the present invention has a molecular weight of from 92 to less than 500, preferably from 92 to 350. For example, glycerin, trimethylolpropane (TMP), 1,2,6-hexanetriol, 1,2,4-butanetriol, diglycerin, pentaerythritol, trimethylolethane, triisopropanolamine, triethanolamine, diisopropanolamine and the like Can be used alone or in combination of two or more.

The polyol / component (B) of the present invention
The weight mixing ratio of short chain diol / short chain triol is used in the range of 75 to 95/5 to 25/0 to 10, respectively.
A preferred range is from 80 to 90/6 to 20/0 to 5. Outside this range, the time required for demolding during molding is insufficiently reduced, and the physical properties are also poor.

The components (A) and (B) of the present invention are NC
It is used so that the equivalent ratio of O group / active hydrogen group becomes 0.8 to 1.20. In this case, the weight mixing ratio A / B is 100
/ 40 to 100/222. If necessary, a catalyst, an additive or the like can be used. As the catalyst, a metal system such as dibutyltin dilaurate and an amine system such as diethanolamine are used. Casting is (A) /
(B) The mixture is poured into a pre-heated mold,
Primary crosslinking at a temperature of ° C. After this primary crosslinking, 10
After secondary crosslinking at 0 to 170 ° C and aging, a urethane elastomer is obtained. The elastomer obtained by using the composition of the present invention is useful in various fields such as rolls, tires and pipes. Also, it can be suitably used for OA equipment.

[0029]

The cast polyurethane elastomer using the composition according to the present invention can be used without impairing general physical properties such as hardness, tensile strength, elongation and compression set.
It also has good casting workability and shows excellent properties such as heat resistance and weather resistance. In particular, by using the isocyanurate ring of HDI together, more excellent heat resistance, weather resistance and the like can be obtained.

[0030]

EXAMPLES The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples. “Parts” and “%” in the examples indicate “parts by weight” and “% by weight”, respectively.

Synthesis Example 1 Preparation of HDR Nurate Modified Form (A-1) 300 parts of HDI was placed in a 500 ml separable flask equipped with a thermometer, a stirrer, and a nitrogen sealed tube, and then 0.05 part of potassium caprate was used as a catalyst. Then, 0.3 part of phenol was added as a co-catalyst, and an isocyanurate-forming reaction was carried out at 60 ° C. for 4.5 hours. To this reaction solution, 0.042 part of phosphoric acid was added as a terminator, and after stirring at 60 ° C. for 1 hour, free HDI was removed by a molecular distillation apparatus. The obtained liquid is a pale yellow transparent liquid having an NCO content of 22.0% and a viscosity of 2100 mP.
aS / 25 ° C, free HDI content 0.4%. This HD
The nullate modified form of I is designated as A-1.

Synthesis Example 2 Production of Nurate Modified HDI (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-2 using 06 parts, 0.3 parts of phenol and 0.072 parts of phosphoric acid. After reacting the polyol with HDI, the NCO content was 45.3%. After distillation,
The NCO content was 19.2%, the viscosity was 2800 mPa.s / 25 ° C, and the free HDI content was 0.3%. This HDR nurate modified product is designated as A-2.

Synthesis Example 3 Preparation of Nurate Modified HDI (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 reacting the polyol with HDI, the NCO content is 48.6.
%Met. After distillation, NCO content 20.5%, viscosity 3
000 mPa.s / 25 ° C., free HDI content 0.4%.
This HDR-modified nurate is referred to as A-3.

Synthesis Example 4 Preparation of Modified Uretdione Nurate (A-4) of HDI
HDI300 parts using the same apparatus as forming A-2, NPG
6.4 parts, 0.4 part of tributylphosphine, phosphoric acid 0.1 part.
The reaction was carried out in the same manner as in A-2 using 6 parts. After the reaction
The CO content was 37.1%. After distillation, the NCO content is 2
1.2%, viscosity 215 mPa.s / 25 ° C, free HDI content 0.
2%. This HDI dimer is 32% HDI
Was 28%. This uretdione-nurate modified form of HDI is designated as A-4.

Synthesis Example 5 Preparation of Modified Uretdione Nurate (A-5) of HDI
HDI300 parts using the same apparatus as forming A-4, BEPD
The reaction was carried out in the same manner as in A-5, using 6.0 parts, 0.3 parts of tributylphosphine and 0.33 parts of methyl paratoluenesulfonate. After the reaction, the NCO content was 39.0%. After distillation, the NCO content was 21.9% and the viscosity was 170 mPa.
s / 25 ° C, free HDI content 0.2%. The dimer of HDI was 43%, and the trimer of HDI was 31%. This HD
The uretdione-nurate modified form of I is designated as A-5.

Examples 1 to 4 Polyurethane elastomer composition and elastomer
Production (A) MDI-based polyisocyanate and HDI-based polyisocyanate are used as the polyisocyanate for the NCO group-terminated prepolymer, and the HDI-based polyisocyanate uses A-1 of Synthesis Example 1, and poly (hexamethylene carbonate) is used as the polyol. ) Using diol and polycaprolactone polyol, a polyurethane elastomer composition comprising (B) poly (hexamethylene carbonate) diol), polycaprolactone polyol, BHEB and TMP was obtained. [Production of Elastomer] In a separable flask equipped with a thermometer, a stirrer, and a nitrogen sealed tube, the HDR-nullated modified product (A-1) of Synthesis Example 1 and MDI-based polyisocyanate were used to prepare poly (hexamethylene carbonate) diol. Using polycaprolactone diol in the proportions shown in Table 1,
The reaction was carried out at 70 ° C. for 3 hours while stirring under a nitrogen stream.
A viscous prepolymer (A) was obtained. Table 1 shows the NCO group content and the like. Poly (hexamethylene carbonate) diol, polycaprolactone polyol, BHEB, and TMP were added to the thus obtained prepolymer (A) at the ratio shown in Table 1 as the component (B), and the mixture was thoroughly stirred until the mixture became completely uniform. After that, defoaming was performed at a reduced pressure of 10 Torr or less until the foaming stopped. This mixture was poured into a centrifugal molding machine preheated to 130 ° C., primary curing was performed at 130 ° C. for 1 hour, and the obtained plate-like polyurethane was secondarily crosslinked at 120 ° C. for 2 hours, and then further cured at room temperature for 1 hour.
After aging for a week, an elastomer was obtained. The prescription is shown in Table 1 and the results are shown in Table 2.

[0037]

[Table 1]

Description of Table 1 MT (1): MDI containing isomer (4,4'-MD
I 71%, 2,2'-MDI 1.8%, 2,4'-
MDI 27.2%) MT (2): Dimer-modified 4,4′-MDI (containing 15% of dimer compound) NCO content 31.1% MTL (1): Carbodiimide-modified MDI (Millionate MTL manufactured by Nippon Polyurethane Industry Co., Ltd.) , NCO content 2
MT (3): MDI containing isomer (4,4'-MD
I 83%, 2,2'-MDI 0.8%, 2,4'-
MDI 16.2%) Polyol (A): Poly (hexamethylene carbonate) polyol (molecular weight 1000, OH number 112) Polyol (B): Poly (hexamethylene carbonate) polyol (molecular weight 1500, OH number 74.8) Polyol ( C): Poly (hexamethylene carbonate) polyol (molecular weight 2000, OH value 56.1) Polyol (D): Polycaprolactone polyol,
(Molecular weight 1000, OH value 112) Polyol (E): polycaprolactone polyol,
(Molecular weight 1500, OH value 74.8) Polyol (F): polycaprolactone polyol,
(Molecular weight 2000, OH value 56.1) Short-chain diol: BHEB Short-chain triol: TMP

[0039]

[Table 2]

Description of Table 2 The hardness (JIS A) was measured one day and one week after the completion of the secondary crosslinking. The demolding time was such that the molded product had no tackiness and could be easily removed from the mold at a primary curing temperature of 130 ° C. Physical property values conformed to JIS K6301.

Examples 5-8 Polyurethane Elastomer Composition and Elastomer
Production (A) MDI-based polyisocyanate and HDI-based polyisocyanate are used as the polyisocyanate for the NCO group-terminated prepolymer, and HDI-based polyisocyanate is A-2 of Synthesis Example 2, and poly (hexamethylene carbonate) is used as the polyol. ) Using a diol and a polycaprolactone polyol, a polyurethane elastomer composition comprising (B) a poly (hexamethylene carbonate) diol, a polycaprolactone polyol, BHEB and TMP was obtained. [Production of Elastomer] Using polyisocyanate and polyol under the conditions shown in Table 3, the reaction was carried out in the same manner as in Example 1 to obtain viscous prepolymer A. Table 3 shows the NCO group content and the like. A polyurethane elastomer was obtained in the same manner as in Example 1, except that the component (B) was used for the prepolymer A component thus obtained under the conditions shown in Table 3. Table 4 shows the results
Shown in

[0042]

[Table 3]

[0043]

[Table 4]

Examples 9-12 Polyurethane Elastomer Composition and Elastomer
Production (A) MDI-based polyisocyanate and HDI-based polyisocyanate are used as the polyisocyanate for the NCO-terminated prepolymer, and HDI-based polyisocyanate is A-3 of Synthesis Example 3, and poly (hexamethylene carbonate) is used as the polyol ) Using diol and polycaprolactone polyol, a polyurethane elastomer composition comprising (B) poly (hexamethylene carbonate) diol), polycaprolactone polyol, BHEB and TMP was obtained. [Production of Elastomer] Using polyisocyanate and polyol under the conditions shown in Table 5, the reaction was carried out in the same manner as in Example 1 to obtain viscous prepolymer A. Table 5 shows the NCO group content and the like. A polyurethane elastomer was obtained in the same manner as in Example 1, except that the component (B) was used for the prepolymer A component thus obtained under the conditions shown in Table 5. Table 6 shows the results
Shown in

[0045]

[Table 5]

[0046]

[Table 6]

Examples 13-16 Polyurethane Elastomer Composition and Elastomer
Production (A) MDI-based polyisocyanate and HDI-based polyisocyanate are used as the polyisocyanate for the NCO group-terminated prepolymer, and the HDI-based polyisocyanate uses A-4 of Synthesis Example 4, and poly (hexamethylene carbonate) is used as the polyol. ) Using diol and polycaprolactone polyol, a polyurethane elastomer composition comprising (B) poly (hexamethylene carbonate) diol), polycaprolactone polyol, BHEB and TMP was obtained. [Production of Elastomer] Using polyisocyanate and polyol under the conditions shown in Table 7, the reaction was carried out in the same manner as in Example 1 to obtain viscous prepolymer A. Table 7 shows the NCO group content and the like. A polyurethane elastomer was obtained in the same manner as in Example 1, except that the component (B) was used for the prepolymer A component thus obtained under the conditions shown in Table 7. Table 8 shows the results.
Shown in

[0048]

[Table 7]

[0049]

[Table 8]

Examples 17-20 Polyurethane Elastomer Composition and Elastomer
Production (A) MDI-based polyisocyanate and HDI-based polyisocyanate are used as the polyisocyanate for the NCO-terminated prepolymer, and HDI-based polyisocyanate is A-5 of Synthesis Example 5, and poly (hexamethylene carbonate) is used as the polyol. ) Using diol and polycaprolactone polyol, a polyurethane elastomer composition comprising (B) poly (hexamethylene carbonate) diol), polycaprolactone polyol, BHEB and TMP was obtained. [Production of Elastomer] Using polyisocyanate and polyol under the conditions shown in Table 9, the reaction was carried out in the same manner as in Example 1 to obtain viscous prepolymer A. Table 9 shows the NCO group content and the like. A polyurethane elastomer was obtained in the same manner as in Example 1, except that the component (B) was used as the prepolymer A component thus obtained under the conditions shown in Table 9. Table 1 shows the results
0 is shown.

[0051]

[Table 9]

[0052]

[Table 10]

Comparative Examples 1-4 Using a polyisocyanate and a polyol under the conditions shown in Table 11, the mixture was reacted at a temperature of 60-70 ° C. for 3 hours with stirring under a nitrogen stream to obtain a viscous prepolymer A component. I got Table 11 shows the NCO group content and the like. The component (B) was used for the prepolymer A component thus obtained under the conditions shown in Table 11, and the mixture was thoroughly stirred until the A / B mixture became completely transparent. Was performed for 60 minutes until foaming subsided. This A / B mixture was injected into a centrifugal molding machine preheated to 130 ° C, and primary curing was performed at 130 ° C for 1 hour. The obtained plate-like polyurethane was secondarily crosslinked at 120 ° C. for 2 hours, and then aged at room temperature for 1 week to obtain a polyurethane elastomer. Table 12 shows the results.

[0054]

[Table 11]

[0055]

[Table 12]

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location C08G 18/79 C08G 18/79 A

Claims (2)

[Claims] 1. A polyurethane elastomer composition comprising an NCO-terminated prepolymer as a component (A) and a mixture of a long-chain polyol, a short-chain diol and a short-chain triol as a component (B). As the isocyanate, a diphenylmethane diisocyanate-based polyisocyanate and a hexamethylene diisocyanate-based polyisocyanate are used, and the diphenylmethane diisocyanate-based polyisocyanate is a diphenylmethane diisocyanate and / or a carbodiide-modified diphenylmethane diisocyanate containing an isomer-containing diphenylmethane diisocyanate and / or a diphenylmethane diisocyanate dimer compound. Containing diphenylmethane diisocyanate and hexamethylene diisocyanate DOO-based polyisocyanates, isocyanurate ring-containing modifications thereof of hexamethylene diisocyanate, or consist uretdione rings and isocyanurate ring-containing modified product of hexamethylene diisocyanate, a polyol for the NCO-terminated prepolymer and (B)
A two-component cast polyurethane elastomer composition, characterized in that the long-chain polyol component is a combination of a polycarbonate polyol and a polycaprolactone polyol, and / or a poly (carbonate-caprolactone) polyol. 2. A polyurethane, wherein the component (A) and the component (B) are mixed and cast at 35 to 95 ° C. using the polyurethane elastomer composition for two-component casting according to claim 1. A method for producing an elastomer.