JPH0413712A - Urethane prepolymer and composition containing the same prepolymer - Google Patents

Abstract

PURPOSE:To obtain a polyurethane prepolymer free from smell and toxicity, providing a polyurethane having excellent hot water resistance, wet heat resistance, etc., by reacting a specific hydroxyl group-containing liquid diene-based polymer with 2,4-tolylene diisocyanate, etc., in a specific ratio. CONSTITUTION:(A) A hydroxyl group-containing liquid diene-based polymer having 600-2,000 number-average molecular weight and 1.9-2.7 average functional groups is reacted with (B) 2,4-tolylene diisocyanate and/or isophorone diisocyanate in the ratio of NCO of the component B/OH of the component A=1.6-2.2 to give a urethane prepolymer containing <=1wt.% free isocyanate. The prepolymer is mixed with a polyamine compound and/or a polyol compound to further improve hot water resistance and wet heat resistance of polyurethane.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a prepolymer for producing urethane and a polyurethane composition containing the same. The present invention relates to a prepolymer and a polyurethane composition containing the same.

[Prior Art and Problems to be Solved by the Invention] Tolylene diisocyanate (TDI) prepolymers of poly(oxytetramethylene) glycol have been known as prepolymers for producing polyurethane. A polyurethane composition composed of this prepolymer and a polyamine compound is used in the field of elastomers such as urethane rolls as an elastic body having superior mechanical strength etc. compared to ordinary polyurethane compositions. However, it has been pointed out that the above composition has insufficient hot water resistance and moist heat resistance.

On the other hand, hydroxyl group-containing diene polymers are known as raw material polyols for obtaining polyurethanes with excellent hot water resistance and moist heat resistance. However, the TD produced using this
The I prepolymer has a high amount of residual TDI, and not only has problems with odor and toxicity during storage and use, but also has a major drawback of having a very short pot life.

[Means to solve the problem]

Therefore, the present inventors conducted intensive research to obtain a urethane prepolymer that solved the above problems and a polyurethane composition using the same, and found that a specific hydroxyl group-containing liquid diene polymer and a specific isocyanate compound were They discovered that it is sufficient to mix them in the appropriate ratios, and completed the present invention.

That is, the present invention provides (a) a number average molecular weight of 600 to 2.0;
00 and a hydroxyl group-containing liquid diene polymer having an average functional group number of 1.9 to 2.7, and (b) 2,4-tolylene diisocyanate and/or isophorone diisocyanate, the hydroxyl group (OH ) and the isocyanate group (NGO) of component (b) (NGOloR
) is 1.6 to 2.2, and the free isocyanate group is 1% by weight or less, and the urethane prepolymer is blended with a polyamine compound and/or a polyol compound. A composition is provided.

The hydroxyl group-containing liquid diene polymer used as component (a) in the present invention is known or can be easily produced by known methods. For example, carbon number is 4-22
diene monomer (butadiene.

isoprene, chloroprene, 1,3-pentadiene, cyclopentadiene, etc.) or two of these diene monomers.
A mixture of hydrogen peroxide and an azo compound having a hydroxyl group (for example, 2,2゛-azobis[2-methyl-N-(2
A hydroxyl group-containing liquid diene polymer can be obtained by radical polymerization using a hydroxyl group-containing peroxide (for example, cyclohexanone peroxide, etc.) as a polymerization initiator.

Furthermore, a hydroxyl group-containing liquid diene polymer can also be obtained by anionically polymerizing a diene monomer using a catalyst such as naphthalene dilithium to produce a living polymer, and then reacting with a monoepoxy compound or the like. Additionally, addition polymerizable monomers having 2 to 22 carbon atoms such as butene, pentene, styrene, a-methylstyrene, acrylonitrile, acrylic acid and its esters, methacrylic acid may be added at a ratio of 50+o1% or less to the diene monomer during polymerization, if necessary. and its esters.

Vinyl chloride, vinyl acetate, acrylamide, etc. can also be added.

Here, the number average molecular weight of the hydroxyl group-containing liquid diene polymer as component (a) is 600 to 2000, preferably 90.
It needs to be between 0 and 1600.

If the number average molecular weight is less than 600, the elasticity of the polyurethane composition using the obtained urethane prepolymer will be poor, which is undesirable. On the other hand, if the number average molecular weight exceeds 2000, gelation will occur and the desired prepolymer is not obtained.

Furthermore, the average value of hydroxyl groups per molecule of the hydroxyl group-containing liquid diene polymer (a) component (hereinafter referred to as the average number of functional groups) is 1.9 to 2.7, preferably 2.0 to 2.
．． Must be 5. If the average number of functional groups is less than 1.9, the elasticity of polyurethane or polyurethane/polyurea produced using the obtained urethane prepolymer will be poor, which is not preferable. On the other hand, if the average number of functional groups exceeds 2.7, gelation occurs and the desired prepolymer cannot be obtained.

The hydroxyl group of the liquid diene polymer may be located at any position within the two molecular chains at the end of the molecular chain, but preferably at the end of the molecular chain. Furthermore, in the present invention, in synthesizing the urethane prepolymer, two or more types of hydroxyl group-containing liquid diene polymers may be mixed and used. In particular, when outstanding heat resistance and weather resistance are required, it is desirable to hydrogenate the double bonds in the skeleton of the hydroxyl group-containing liquid diene polymer before use.

The skeleton structure of the hydroxyl group-containing liquid diene polymer as component (a) preferably has a 1,4-structure of 50so1% or more in order to exhibit good elasticity as an elastomer.

Next, in the present invention, 2,4-tolylene diisocyanate and/or isophorone diisocyanate is used as component (b).

The 2,4-tolylene diisocyanate is preferably a pure product, but it is a 2,6-) diisocyanate in a proportion (up to 35% by weight) that does not interfere with the production of urethane prepolymers.

The urethane prepolymer of the present invention comprises the above component (a) and (
c) Components at 0 to 150°C2 preferably 20 to 120°C
It is obtained by reacting for 0.1 to 100 hours, preferably 0.5 to 50 hours. At this time, the hydroxyl group (OH) of component (a) and the isocyanate group (NGO
It is necessary to mix component (a) and component (a) so that the molar ratio (NGOloH) of ) is 1.6 to 2.2, preferably 1.7 to 2.1. Here, the molar ratio is 1.6
If it is less than that, gelation will occur during the reaction, which is not preferable.

On the other hand, when it exceeds 2.2, the amount of free (residual) isocyanate groups in the obtained urethane prepolymer exceeds 1% by weight, which is not preferable because it causes problems with odor and toxicity during storage and use.

In the present invention, the additives shown below can be added to the reaction of component (a) and component Φ), but in that case, the amount of free isocyanate groups in the urethane prepolymer finally obtained is 1% by weight. It is necessary to add the following amount.

Furthermore, in obtaining the urethane prepolymer of the present invention, the following curing accelerating catalyst and viscosity modifier are used.

Various additives such as a solvent can be added before the reaction, during the reaction, or at an appropriate time after the reaction.

Examples of catalysts that promote the curing reaction include triethylenediamine, tetramethylguanidine, N, N, and N'.

N”-tetramethylhexane-1,6-diamine, N.

N, N'N"N'"-pentamethyldiethylenetriamine, bis(2-dimethylaminoethyl)ether, 1,
2-dimethylimidazole, N-methyl-N'-(2-
Tertiary amines or their carboxylates such as (dimethylamino)-ethylpiperazine, diazabicycloundecene, stannas octoate dibutyltin diacetate, dibutyltin dilaurate, dibutyltin mercaptide, dibutyltin thiocarboxylate, dibutyltin dimaleate , dioctyltin mercaptide, dioctyltin thiocarboxylate, phenylmercury propionate, lead octenoate, and other organometallic compounds. The amount of catalyst added should be at most 10 parts by weight per 100 parts by weight of component (a). If the amount added exceeds 10 parts by weight, not only the curing accelerating effect reaches its peak, but also the risk of local abnormal reaction (gelation) increases, which is not preferable.

As the viscosity modifier, plasticizers such as dioctyl phthalate, process oils such as paraffinic, naphthenic, and aromatic oils, olefin oligomers, alkylbenzenes, alkylnaphthalenes, alkyldiphenylethanes, silicone oils, and the like can be used. The amount of viscosity modifier added should be less than 50% by weight of the resulting urethane prepolymer. If it exceeds 50% by weight, the physical properties of polyurethane or polyurethane/polyurea produced using the urethane prepolymer will deteriorate, which is not preferable.

Next, as a solvent, n-hexane, cyclohexane,
Hydrocarbon solvents such as toluene and xylene, ketone solvents such as methyl ethyl ketone and cyclohexanone, ester solvents such as butyl acetate, ester solvents such as tetrahydrofuran, N,N-diethylformamide, dimethyl sulfoxide, etc. can be used. This solvent is mainly used for the purpose of lowering the viscosity, and the amount added should be 30% by weight or less of the urethane prepolymer obtained. If it exceeds 30% by weight, the urethane prepolymer will not be produced Polyurethane or polyurethane
This is not preferred because the physical properties of polyurea deteriorate.

Furthermore, the present invention also provides a polyurethane composition obtained by blending a polyamine compound and/or a polyol compound with the above-mentioned urethane prepolymer.

The polyamine compound used in the present invention is a compound having an amino group having two or more active hydrogens in one molecule. Specifically, aliphatic polyamines such as hexamethylene diamine and polyoxypropylene polyamine, 3,
Alicyclic polyamines such as 3′-dimethyl-4,4′-diaminodicyclohexylmethane, 3,3″-dichloro-4
, 4'-diaminodiphenylmethane, 3,5-diethyltoluene-2,4-diamine, and 3,5-diethyltoluene-2,6-diamine. The blending ratio of the polyamine compound is such that the molar ratio (NCO/NHz) of the isocyanate group (NGO") of the urethane prepolymer to the amino group (Nlh) of the polyamine compound is 0.5 to 2.0, preferably 0.7. ~1.5, where:
If the molar ratio is less than 0.5 or exceeds 2.0, the physical properties of the resulting polyurethane composition (polyurethane/polyurea) will deteriorate, which is not preferable.

Next, the polyol compound used in the present invention is a compound having two or more hydroxyl groups in one molecule, and preferably has a molecular weight of 50 to 500. Also, primary polyols and secondary polyols.

Any tertiary polyol may be used. in particular,
1,2-propylene glycol, dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-bentanediol, 2,3-bentanediol.

2,5-hexanediol, 2,4-hexanediol, 2-ethyl-1,3-hexanediol.

Cyclohexanediol, glycerin, N,N-bis-
2-hydroxypropylaniline, N,N'-bishydroxyisopropyl-2-methylpiperazine, propylene oxide adduct of bisphenol A, etc. (both are low molecular weight polyols containing a hydrogen group bonded to one secondary carbon) Furthermore, ethylene glycol, diethylene glycol, 1,3-propylene glycol, 1.
4-butanediol, 1,5-bentanediol.

1.6-hexanediol, trimethylolpropane,
Pentaerythritol, dipentaerythritol, etc. can also be used.

Furthermore, as a zero-polymerization type polyol compound that can also use a polymerization type polyol or a castor oil-based polyol,
Polymerizable polyol compounds having a number average molecular weight of 500 to 10,000 and commonly used as raw materials for polyurethane can be used, specifically polyether polyols and modified products thereof.

Polytetraethylene ether glycol, tetrahydrofuran/alkylene oxide copolymer polyol, epoxy resin modified polyol, polyester polyol,
Examples include polydiene polyols, partially phosphoric acid ethylene-vinyl acetate copolymers, and the like. In addition, castor oil-based polyols include castor oil, hydrogenated castor oil,
Examples include castor oil transesterified products. These polymerized polyols or castor oil-based polyols are
A mixture of two or more types can also be used. The polymerizable polyol or castor oil polyol is preferably used in combination with other polyols, and the amount thereof is preferably 30% by weight or less based on the total amount of the polyurethane composition (polyurethane).

The blending ratio of the polyol compound is usually the molar ratio of the isocyanate group (NGO) of the urethane prepolymer to the hydroxyl group (OH) of the polyol compound (NCOl
The polyol compound is blended so that the oH) is 0.5 to 2.0, preferably 0.7 to 1.5.

Here, if the molar ratio is less than 0.5 or exceeds 2.0, the physical properties of the resulting polyurethane composition will deteriorate, which is not preferable.

The polyurethane composition of the present invention is composed of the above-mentioned urethane prepolymer, polyamine compound and/or polyol compound, but if desired, in addition to the above-mentioned components, fillers and additives used in the production of the urethane prepolymer (catalyst, viscosity Conditioners, solvents) can be added.

As the filler, either an inorganic filler or an organic filler may be used. Specifically, the inorganic filler includes zinc, asbestos alumina, and aluminum.

Kaolin clay, glass spheres, glass flakes, glass fibers, carbon (channel black, furnace black, acetylene black, thermal black) carbon fibers, nepheline, cryolite, graphite silica, wollastonite, diatomaceous earth, zinc oxide, oxide Magnesium, zirconium oxide, titanium oxide, iron oxide, aluminum hydroxide,
Magnesium hydroxide, slate powder, zeolite, quartz powder.

Examples include calcium carbonate, magnesium carbonate, talc, potassium titanate, boron nitride, feldspar powder, copper, nickel, molybdenum disulfide, barium sulfate, whiting, waxite clay, mica, and ceracola. In addition, organic fillers include rubber powder, cellulose, lignin, chitin, leather powder, coconut shell, wood flour, cotton, hemp, wool,
Natural fibers such as silk, nylon, polyester, vinylon.

Synthetic fibers such as acetate and acrylic, polyethylene, polypropylene, polystyrene, ABsmllL polyml
Method 1, polyethylene terephthalate, polybutylene terephthalate, polymethyl methacrylate, polyvinyl chloride resin, epoxy resin.

Examples include synthetic resin powder or granules such as phenol resin. The blending amount of these inorganic fillers and organic fillers is preferably 30% by weight or less based on the total amount of the polyurethane composition.

The polyurethane composition of the present invention can be obtained by blending and mixing the above components. Usually, the urethane prepolymer and other components are heated at 0-120°C, preferably at 5-120°C.
After stirring and mixing at 100° C., a cured product may be obtained by a conventional method such as press hardening.

〔Example〕

Next, the present invention will be explained by examples.

Production Example 1 Preparation of liquid polyisoprene having a hydroxyl group at the end of the molecular chain 1! Isoprene 200 was added to a stainless steel pressure-resistant reaction vessel.
During the reaction, the pressure reached a maximum of 8 kg/cjG. .

After the reaction is complete, put the reaction mixture into a separating funnel and add 600g
of water was added, the mixture was shaken, and the mixture was allowed to stand for 3 hours, after which the oil phase was separated. From this oil phase, the solvent, monomer, and low boiling point components are removed.
-aug, 100°C, and 2 hours to obtain liquid polyisoprene having a hydroxyl group at the end of the molecular chain (yield: 66% by weight). The number average molecular weight of this product is 2240. The hydroxyl group content was 0.96 meq/g, the viscosity was 64 poise/30°C, and the bromine number was 220 g/100 g.

Structural analysis of the obtained liquid polyisoprene by 'H-NMR revealed that it was 32% 1.4-cis, 58% 1,4-trans, 4% 1,2-vinyl, and 6% 3.4-vinyl. Ta.

Production Example 2 Preparation of liquid polyisoprene having a hydroxyl group at the end of the molecular chain Into the stainless steel pressure-resistant reaction vessel of 11, 200 g of isoprene was added.
g, 52 g of 50% by weight hydrogen peroxide solution and 290 g of isopropanol were charged, and the reaction was carried out at a temperature of 115° C. for a reaction time of 2° and 5 hours. During the reaction, the pressure reached a maximum of 7 kg/ciiG. After the reaction was completed, the reaction mixture was placed in a separatory funnel, 600 g of water was added thereto, and the mixture was shaken. After standing for 3 hours, the oil phase was separated. From this oil phase, the solvent, monomer, and low boiling point components were extracted at 2 dg at 100°C.
The residue was distilled off for a certain amount of time to obtain liquid polyisoprene having a hydroxyl group at the end of the molecular chain (yield: 66% by weight). The number average molecular weight of this product is 1410. Hydroxyl group content is 1.44 s
eq/g, and the viscosity was 64 voids/30°C.

Structural analysis of the obtained liquid polyisoprene by 'H-NMR revealed that it was 33% 1,4-cis, 58% 1,4-trans, 4% 1,2-vinyl, and 5% 3,4-vinyl. Ta.

Examples 1 to 2 and Comparative Examples 1 to 3 A 500W glass separable flask equipped with a stirrer, a temperature needle, an Allene condenser, and a N2 seal was charged with the first
A predetermined amount of 2,4-tolylene diisocyanate shown in the table was charged, and the internal temperature was raised to 60°C in an oil bath. A mixture of a diene polymer and a catalyst in a predetermined amount shown in Table 1, which had been placed in a dropping funnel in advance, was added dropwise thereto over one hour while being maintained at 60°C. After the dropwise addition was completed, the internal temperature was raised to 80°C, and stirring was continued for 3 hours. Then, the mixture was cooled to room temperature to obtain a urethane prepolymer. Table 1 shows the properties of the obtained urethane prepolymer.

Table 1 ml Manufactured by Idemitsu Atochem ■, hydroxyl group-containing liquid polybutadiene, skeleton structure of both R-15BT and R~45HT: 1,4cis 22χ, 1,4-trans 59χ, 1,2-
Vinyl 19χ.

$3 Dibutyltin dilaurate book 4 manufactured by Kyodo Yakuhin■
During the reaction, the system became a rubbery solid (gelation), and a prepolymer could not be obtained.

Examples 3 to 7 and Comparative Examples 4 to 5 A predetermined amount of urethane prepolymer shown in Table 2 was heated at 80°
Place it in a constant temperature bath at 120°C for 1 hour, then add other ingredients separately to 120°C.
It was placed in a constant temperature bath at C for 1 hour. Mix these immediately after taking them out of the thermostat, stir for 2 minutes with a spatula heated to 100°C, pour into a mold, press harden at 120°C for 2.5 hours, and harden to a thickness of 2. I got a body. Table 2 shows the physical properties of the obtained cured product.

/ *l Manufactured by Ihara Chemical ■, 3.3'-dichloro-4
,4゜-diaminodiphenylmethane, amine equivalent? ,4
9meq/g - Nippon Nyukazai ■, bisphenol A propylene oxide adduct, hydroxyl group content 5°03seq/g umbrella 380°
There was a strong pungent odor when I took it out of the thermostatic chamber in C.

4 UNIROYAL Inc., poly (oxytetramethylene) glycol/tolylene diisocyanate prepolymer, NGO content 4.1% by weight*5
Gelation occurred during mixing and stirring, and the product could not be poured into a mold.

Compliant with JIS K-6301 [Effects of the Invention] The urethane prepolymer of the present invention has no odor or toxicity during storage or use, and is useful as a material for urethane elastomers. Moreover, the polyurethane composition obtained from the urethane prepolymer of the present invention has excellent hot water resistance and moist heat resistance.

Patent applicant: Idemitsu Petrochemical Co., Ltd. Agent Patent Attorney Kubo 1) Fujibe Rako↓ Procedural amendments issued) August 23, 1990

Claims (2)

[Claims] (1) (a) A hydroxyl group-containing liquid diene polymer having a number average molecular weight of 600 to 2,000 and an average number of functional groups of 1.9 to 2.7, and (b) 2,4-tolylene diisocyanate and/or isophorone diisocyanate. The above (
The molar ratio (NCO/OH) of the hydroxyl group (OH) of component a) and the isocyanate group (NCO) of component (b) is 1.6 to 2.
．． A urethane prepolymer containing 1% by weight or less of free isocyanate groups. (2) A polyurethane composition obtained by blending the urethane prepolymer according to claim 1 with a polyamine compound and/or a polyol compound.