JPH0337564B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to elastomer-forming compositions.
More specifically, the present invention relates to a composition capable of forming a high hardness polyurethane polyurea elastomer. [Prior Art] Elastomer-forming compositions conventionally used in cast elastomers include polyurethane polyurea-based compositions, such as NCO-terminated urethane prepolymers of polyether polyols or polyester polyols and aromatic polyisocyanates such as tolylene diisocyanate. DuPont's Adiprene L series, American Cyanamid's Cyanaprene A series and D series, etc.) and 4,4'-methylenebis(2-chloroaniline), and as a somewhat special composition, polytetramethylene ether NCO-terminated urethane prepolymer of glycol and 1,4-methylenebis(cyclohexyl isocyanate) (Adiprene LW series from Dupont) and 4.
A compound consisting of 4'-methylene dianiline is known. However, these compositions have low tear strength and elongation, and have insufficient durability when subjected to severe repeated stress. Furthermore, the viscosity increases rapidly after mixing the two liquids, which poses a problem in workability. [Problems to be Solved by the Invention] The present inventors have conducted studies to obtain a composition that is a high-hardness elastomer, has improved tear strength and elongation, has good durability, and has improved workability. We have arrived at the present invention. [Means for solving the problem] The present invention provides (A) an NCO-terminated urethane prepolymer made from a polyol having a molecular weight of 62 to 1,600, a polyisocyanate containing an isocyanurate ring, and a non-aromatic diisocyanate, and (B) an aromatic polyamine. and, if necessary, a (C) catalyst. Polyols having a molecular weight of 62 to 1,600 can be used as the raw material polyol for the urethane prepolymer (A) in the present invention. Specifically, polymer polyols such as polyether polyols, polyester polyols,
Included are polymer polyols, polybutadiene polyols, and mixtures of two or more thereof. Polyether polyols include low-molecular polyols (ethylene glycol, propylene glycol,
Bifunctional polyols such as 1,4-butanediol and 1,3-butanediol; trifunctional or higher functional polyols such as glycerin, trimethylolpropane, pentaerythritol, and sucrose),
Amines (alkanolamines such as triethanolamine, N-methyldiethanolamine;
Alkylene oxides of compounds having at least two active hydrogen atoms (alkylene oxides having 2 to 4 carbon atoms) such as aliphatic polyamines such as ethylene diamine; aromatic polyamines such as tolylene diamine, methylene dianiline, polymethylene polyphenyl amine, oxide (e.g. ethylene oxide, propylene oxide, butylene oxide, etc.), ring-opening polymers of alkylene oxides (ring-opening polymerization of tetrahydrofuran, polytetramethylene ether glycol by hydrolysis, etc.); polyester polyols include polycarboxylic acids (fatty polyester polyols obtained by condensation of group polycarboxylic acids such as adipic acid, maleic acid, dimerized linoleic acid, aromatic polycarboxylic acids such as phthalic acid) and polyols (low-molecular polyols or polyether polyols as mentioned above); Lactone polyesters (polycaprolactane, etc.); polymer polyols obtained by polymerizing vinyl monomers (acrylonitrile and/or styrene, etc.) in polyols (polyether polyols, polyester polyols, etc.); polybutadiene polyols: obtained by polymerizing butadiene with a hydroxyl group-containing radical initiator,
Examples include those obtained by adding a compound that becomes a hydroxyl group, such as ethylene oxide, to an active terminal polymer obtained by polymerizing butadiene using an anionic polymerization catalyst such as sodium or lithium. Among these polymer polyols, polyether polyols are preferred, and polytetramethylene ether glycol is particularly preferred. The molecular weight of high molecular weight polyols is usually 200~
1600 preferably 250-900. When a polymer polyol with a molecular weight of more than 1600 is used, it is difficult to obtain a tough and hard elastomer. If necessary, low-molecular polyols (bifunctional polyols such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol; trifunctional or higher functional polyols such as glycerin, trimethylolpropane, pentaerythritol, sucrose, etc.) ) may be used in combination. In this case, the equivalent ratio of high molecular polyol to low molecular polyol is usually 100:1 to 1:1, preferably 50:1 to 10:1. The (average) number of functional groups of the polyol is usually 2 to 8, preferably 2 to 3,
Particularly preferably 2 to 2.5. In the present invention, trimerized organic polyisocyanates can be used as the isocyanurate ring-containing polyisocyanates used as raw materials for the prepolymer component (A). Examples of organic polyisocyanates include alicyclic polyisocyanates such as isophorone diisocyanate, cyclohexane-1,4-diisocyanate, 1,4-methylenebis(cyclohexyl isocyanate);
Aliphatic polyisocyanates; common aliphatic polyisocyanates such as hexamethylene diisocyanate; araliphatic polyisocyanates such as xylylene diisocyanate; aromatic polyisocyanates, such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate; Isocyanate, 2,4-tolylene diisocyanate and 2,
Mixture of 6-tolylene diisocyanate, xylylene diisocyanate, diphenylmethane-4,
4'-diisocyanate, diphenylmethane which is liquid at room temperature - Modified (carbodiimide modified, etc.) polyisocyanates based on 4,4'-diisocyanate, triphenylmethane triisocyanate, 1,3-bis(phenylmethyl)benzene
4,4',4''-triisocyanate; and mixtures of two or more thereof. Among these, preferred are aliphatic and cycloaliphatic polyisocyanates, and particularly preferred is isophorone diisocyanate. Specific examples of trimerized organic polyisocyanates include trimerized isophorone diisocyanate;
Examples include trimerized products of hexamethylene diisocyanate and trimerized products of tolylene diisocyanate. The trimerized organic polyisocyanate can be obtained by a known method. For example, by applying a trimerization catalyst to an organic polyisocyanate,
It can be made into a trimerized product relatively easily. As a trimerization catalyst, see "Polyurethanes Chemistry and Technology" Volume 1 by J.H. SAUNDERS and K.C. FRISCH,
Examples include those described on pages 94-97 and 212. Specific examples include strong organic bases and salts [trialkylphosphine, trialkyl-aminoalkylphenol, N,N′,N″-tris(alkylaminoalkyl)hexahydro-sym
-triazine, etc.], composites with tertiary amine catalysts [triethylenediamine-propylene oxide,
triethylenediamine-trioxymethylene,
N,N,N',N'-tetramethyl-1,3-butanediamine-propylene oxide, etc.], Friedel-Crafts catalysts [ _AlCl3 , _FeCl3 , _BF3 ,
ZnCl _2, etc.], basic salts of weak organic acids [alkali metal (potassium, sodium, etc.) salts of C ₆ - C ₂₀ carboxylic acids, such as potassium octoate, potassium oleate, etc.], alkali metal oxides [potassium oxide, etc.] , sodium oxide, etc.], alkali metal alcoholates [sodium methoxylate, potassium ethoxylate, etc.]. Among these, preferred are strong organic bases and salts. Examples of the non-aromatic diisocyanate in the present invention include the above-mentioned aliphatic diisocyanates, alicyclic diisocyanates, and mixtures of two or more thereof. Among these, cyclohexane-1,4-diisocyanate, 1,4-
Methylenebis(cyclohexyl isocyanate)
and this mixture. The prepolymer (A) in the present invention comprises the above-mentioned polyol, polyisocyanate containing an isocyanurate ring, and non-aromatic diisocyanate.
The reaction is carried out at a rate such that an NCO-terminated urethane prebolimer is produced, and the equivalent ratio (NCO/OH ratio) is usually 1.2 to 5.0, preferably 1.4 to 5.0.
It is 3.5. The ratio of the polyisocyanate containing an isocyanurate ring to the non-aromatic diisocyanate is usually 1:3 to 1:50, preferably 1:5 to 1:25 in terms of equivalent ratio. The urethane prepolymer (A) is usually prepared by reacting the above polyol with a polyisocyanate containing an isocyanurate ring at 70 to 110°C for 1 to 20 hours, then adding the above non-aromatic diisocyanate and heating at 70°C.
It is obtained by reacting at ~110℃ for 1 to 20 hours (two-step method), but the above three components are simultaneously reacted at ~70℃.
It can also be obtained by reacting at 110°C for 1 to 30 hours (one-stage method). Furthermore, free polyisocyanate may remain in the prepolymer. The NCO content of the prepolymer is usually 6.0 to 20% by weight, preferably 7 to 15% by weight. The aromatic polyamine (B) in the present invention has the general formula (In the formula, Y is a divalent organic group or a sulfonyl group, and X ₁ and X ₂ are a halogen atom or a carbon number 1
-4 alkyl group, and n ₁ and n ₂ are 0 or an integer of 1 or more. ) and/or general formula (In the formula, R ₃ is a monovalent organic group and X ₃ has 1 carbon number.
-4 alkoxy group or halogen atom. )
Compounds shown can be used. The divalent organic group of Y in general formula (1) is -
CH ₂ -, -S(CH ₂ ) _n1 S- (where m ₁ is 0 or an integer of 1 to 4, preferably 1 to 3, sometimes 2), -COO-A-OOC- [where A is 2 to an alkylene group with 6 carbon atoms, optionally branched and/or containing an oxygen atom, a sulfur atom or an -N(R) group (R=C ₁ -C ₄ alkyl group) . [Alkylene group preferably having 2 to 4 carbon atoms, especially 3 carbon atoms] and Japanese Patent Publication No. 1987-
-CO-O- described in Publication No. 51959,

[expression] and

〔Example〕

The present invention will be further explained below with reference to production examples and examples, but the present invention is not limited thereto. The parts described below indicate parts by weight. Production Example 1 100 parts of polytetramethylene ether glycol having a number average molecular weight of 700 was placed in a four-necked flask equipped with a stirring rod and a thermometer, and the mixture was heated to 110° C. under reduced pressure of 3 mmHg and dehydrated for 1 hour. Next, a trimerized product of isophorone diisocyanate having an isocyanurate ring (isocyanate equivalent: 223)
10.6 parts of cyclohexane-1,4-diisocyanate were added and reacted at 100°C for 6 hours under a nitrogen stream, and then 60.3 parts of cyclohexane-1,4-diisocyanate was added and the reaction was carried out at 100°C under a nitrogen stream.
The mixture was reacted for 5 hours to obtain prepolymer [A ₁ ].
The free isocyanate content of prepolymer [A(c)] was 11.9%. Production Example 2 100 parts of polytetramethylene ether glycol having a number average molecular weight of 700 was placed in a four-necked flask equipped with a stirring rod and a thermometer, and the mixture was heated to 110° C. under reduced pressure of 3 mmHg and dehydrated for 1 hour. Next, a trimerized product of isophorone diisocyanate having an isocyanurate ring (isocyanate equivalent: 223)
Then, 1.9 parts of 1.4-methylenebis(cyclohexyl isocyanate) was added and reacted at 100℃ for 6 hours under a nitrogen stream.
The reaction was carried out at 100°C for 7 hours to obtain prepolymer [A ₂ ]. The free isocyanate content of the prepolymer [A ₂ ] was 10.2%. Comparative Production Example 1 100 parts of polytetramethylene ether glycol having a number average molecular weight of 700 was placed in a four-necked flask equipped with a stirring bar and a thermometer, and the mixture was heated to 110°C under reduced pressure of 3 mmHg and dehydrated for 1 hour. . Next, cyclohexane-1,4-diisocyanate,
63.3 parts were added and reacted at 100°C for 5 hours under a nitrogen stream to obtain prepolymer [A' ₁ ]. The free isocyanate content of the prepolymer [A′ ₁ ] was 12.1%. Comparative Production Example 2 100 parts of polytetramethylene ether glycol having a number average molecular weight of 700 was placed in a four-necked flask equipped with a stirring bar and a thermometer, and the mixture was heated to 110°C under reduced pressure of 3 mmHg and dehydrated for 1 hour. . Next 2,
Add 81.1 parts of 4-tolylene diisocyanate,
The reaction was carried out at 100° C. for 4 hours under a nitrogen stream to obtain prepolymer [A′ ₂ ]. The free isocyanate content of the prepolymer [A′ ₂ ] was 15.0%. Example 1 The composition of the present invention was made into a prepolymer [A ₁ ] and a mixture of 4,4'-methylenebis(2-chloroaniline) and an adipic acid catalyst [B ₁ , C ₁ ]. [A ₁ ] and [B ₁ , C ₁ ] at 90℃ and 120℃, respectively.
Weigh the specified amount into a beaker at ℃, mix thoroughly for 30 seconds with a baby motor equipped with a screw-type stirring blade, degas for 1 minute under reduced pressure of 3 mmHg, and then quickly pour into a mold heated to 110℃. is. After heating the mold at 110°C for 1 hour, the cured product was demolded,
A sheet-like urethane resin molded product with a thickness of 2 mm and a cylindrical urethane resin molded product with a thickness of 12.7 mm and a diameter of 29 mm were obtained. The obtained sheet-like and cylindrical molded products are
After heating and curing at 110°C for 15 hours and curing at room temperature for one week, it was subjected to physical property measurements. Example 2 The composition of the present invention was made into a prepolymer [A ₂ ] and a mixture of 4,4'-methylenebis(2-chloroaniline) and triethylenediamine [B ₁ , C ₁ ]. [A ₂ ] and [B ₁ , C ₁ ] at 90℃,
A predetermined amount was weighed into a beaker at 120° C., and sheet-like and cylindrical molded products were produced under the same conditions as in Example 1. Comparative Example 1 Prepolymer [A' ₁ ] and 4,4'-methylene dianiline [B ₂ ] were used as compositions for comparison. [A′ ₁ ] and [B ₂ ] at 90℃ and 120℃, respectively.
A predetermined amount was weighed into a beaker at ℃, and sheet-like and cylindrical molded products were created under the same conditions as in Example 1. Comparative Example 2 The compositions for comparison were prepolymer [A' ₂ ] and 4,4'-methylenebis(2-chloroaniline [B ₂ ]. [A' ₂ ] and [B ₁ ] were each 80% ℃，120
A predetermined amount was weighed into a beaker at ℃, and sheet-like and cylindrical molded products were created under the same conditions as in Example 1. Test Example 1 Performance tests were conducted on the compositions of Examples 1 and 2 and Comparative Examples 1 and 2. The results are shown in Table-1.

〔Effect of the invention〕

The high hardness polyurethane polyurea elastomer obtained by curing the composition of the present invention is strong and has high breaking strength and elongation. It has good durability without breaking even under severe repeated stress. In addition, the viscosity increases slowly after mixing the two liquids, improving workability and making it suitable for manufacturing large, complex-shaped molded products. Furthermore, the decrease in hardness at high temperatures is small and it can be used even at high temperatures. Because of these effects, the high hardness polyurethane polyurea elastomer composition of the present invention is required to withstand repeated high loads, such as in industrial rolls such as paper rolls and steel rolls, solid tires, sprockets, and industrial parts. Suitable for this purpose.

Claims (1)

[Scope of Claims] 1 (A) NCO-terminated urethane prepolymer from a polyol with a molecular weight of 62 to 1600, a polyisocyanate containing an isocyanurate ring, and a non-aromatic diisocyanate, (B) an aromatic polyamine and optionally (C) A polyurethaneurea elastomer-forming composition comprising a catalyst. 2. The composition according to claim 1, wherein the polyol comprises a high molecular weight polyol having a molecular weight of 200 to 1600 and, if necessary, a low molecular weight polyol. 3. The composition according to claim 2, wherein the polymer polyol is a polyether polyol. 4 The molecular weight of the polyether polyol is 200~
900. The composition according to claim 3, wherein the composition is 5. The composition according to claim 4, wherein the polyether polyol is polytetramethylene ether glycol. 6. The composition according to any one of claims 1 to 5, wherein the aromatic polyamine is an aromatic polyamine having an electrophilic substituent. 7 Aromatic polyamine is 4,4′-methylenebis(2-chloroaniline) and/or 4,4′-methylenebis(2-chloroaniline)
7. A composition according to any one of claims 1 to 6, which is 4'-diaminodiphenyl sulfone. 8. The composition according to any one of claims 1 to 7, wherein the polyisocyanate containing an isocyanurate ring is a trimerized product of an aliphatic polyisocyanate or an alicyclic polyisocyanate. 9. The composition according to claim 8, wherein the trimerized alicyclic polyisocyanate is a trimerized product of isophorone diisocyanate. 10 Claims 1 to 9, wherein the non-aromatic diisocyanate is cyclohexane-1,4-diisocyanate and/or 1,4-methylenebis(cyclohexyl isocyanate)
A composition according to any one of paragraphs. 11 NCO content of urethane prepolymer is 7~
Claims 1 to 1 which are 15% by weight
The composition according to any one of item 0.