JPH04164914A - Two-pack foaming polyurethane elastomer composition for sole - Google Patents

Abstract

PURPOSE:To obtain the title composition which can give a sole improved in mechanical strength, water resistance and flex resistance by mixing an isocyanate component comprising an organic polyisocyanate with a polyol component containing a specified polyol. CONSTITUTION:Polyoxytetramethylene glycol (i) of a molecular weight of 400-10,000, desirably 800-3,000, prepared by, for example polymerization of tetrahydrofuran through ring opening is addition-polymerized with 5-50wt.%, desirably 10-40wt.% lactone to obtain a polyol. The polyol is mixed with optionally a chain extender, a catalyst, a blowing agent, a foam stabilizer, a stabilizer, a pigment, etc., to obtain a polyol component. This component is mixed with an isocyanate component comprising an organic polyisocyanate and/or another organic polyisocyanate comprising a prepolymer prepared from the above polyisocyanate and a polyol to obtain the title composition.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a polyurethane composition for shoe soles, and more specifically, a composition for shoe soles that has excellent mechanical strength, water resistance, and bending resistance. The present invention relates to a two-component cellular polyurethane elastomer composition.

(Prior art) Shoes can be roughly classified into men's leather shoes, women's leather shoes, sports shoes, canvas shoes, women's chemical shoes, men's chemical shoes, hep sandals, etc., and the sole materials include rubber, leather, 1° 2-polybutadiene type, polyvinyl chloride type, and polyurethane type are widely used.

Cellular polyurethane elastomer is lightweight, has excellent mechanical strength, mold resistance, bending resistance, chemical resistance, slip resistance, and cold resistance, and is also excellent in productivity such as continuous demolding and integral molding. It is applied in a wide variety of ways.

In particular, polyester-based cellular polyurethane elastomers made of adipic acid ester and 4,4'-diphenylmethane diisocyanate (hereinafter abbreviated as MDI) are often used, but their drawbacks include poor water resistance and high resistance, and they do not absorb water easily. When stored, it is subject to severe damage, resulting in extremely low corrosion resistance and mechanical strength, making it prone to falling apart. In recent years, in order to improve this, polyoxyalkylene glycol, polyoxyalkylene triol and MD
A polyether-based cellular polyurethane elastomer consisting of I was developed, and its water resistance and piping resistance have been improved, but mechanical strength, abrasion resistance, and chemical resistance are superior to polyester-based cellular polyurethane elastomers. inferior in comparison.

Conventional techniques related to cellular polyurethane elastomers that improve both mechanical strength, water resistance, and piping resistance include the following. That is, JP-A-62-257
Publication No. 923 describes C2-1□ glycol, adipic acid, and gel tar as a measure to improve both the mechanical strength and water resistance of polyurethane and polyurethane-urea cellular and non-cellular elastomers for automobile bumpers and shoe soles. 10 to 70 parts by weight of a polyester diol consisting of acid and/or succinic acid, 1 to 90 parts by weight of polyoxytetramethylene glycol (Mw 162 to 600), and polyoxyalkylene glycol (Mw 106 to 1)
000) Hydroxy compound consisting of 0 to 50 parts by weight (
There is a description of a composition comprising OHV 25-100) and an organic polyisocyanate.

Furthermore, JP-A-61-181815 discloses that as a measure to improve the mechanical strength and repeated compression durability of cellular polyurethane elastomers, 20 to 50% of polyoxyalkylene polyol residues of 260 to 1800 are added. There is a description of a composition comprising a polyol compound comprising a polyester polyol having a molecular weight of 800 to 3,600, a blowing agent, and a foam stabilizer, and an organic polyisocyanate and/or a urethane prepolymer.

JP-A-63-101412 discloses that 3-methyl-1,
There is a description of a polyurethane composition comprising a polyol component containing 50 to 100% by weight of a condensed polyester polyol of 5-bentanediol and dicarboxylic acid, a polyisocyanate component, a chain extender, and a blowing agent. In addition, polyurethanes made of polycaprolactone diol and polyoxytetramethylene glycol are known to have excellent mechanical strength and water resistance, but when applied to cellular polyurethane elastomers, they have poor bending resistance and are used for shoe soles. As such, it is unreachable and cannot be put to practical use.

(Problems to be Solved by the Invention) The object of the present invention is to provide a two-component cellular polyurethane elastomer composition for shoe soles that has excellent mechanical strength, water resistance, and bending resistance.

(Means for Solving the Problems) As a result of intensive research to solve the problems, the present inventors have completed the present invention.

That is, the present invention provides (A) an organic polyisocyanate, (B
) A two-component cellular polyurethane elastomer composition for shoe soles consisting of a polyol obtained by addition polymerizing lactone to polyoxytetramethylene glycol, and furthermore, an organic polyisocyanate (A) is a prepolymer obtained by reacting a polyol with an organic polyisocyanate. The composition is characterized in that the polyol (B) has a lactone addition rate of 5 to
The present invention provides a composition characterized in that the composition is 50% by weight, and a shoe sole made of the composition.

(Composition) The two-component cellular polyurethane elastomer uses organic polyisocyanate and/or urethane prepolymer as the isocyanate component, and contains polyol, chain extender, catalyst, blowing agent, foam stabilizer as the main components, and other components depending on the purpose. It consists of a polyol component of a polyol compound made by mixing various stabilizers (weather resistance, piping resistance, heat resistance improvers, etc.), pigments, etc.

The organic polyisocyanate (A) used in the present invention is
4,4'-diphenylmethane diisocyanate, carbodiimide-modified diphenylmethane diisocyanate (liquefied MDI), polyphenylene polyisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, ferlene diisocyanate, cyclohexane diisocyanate, xylylene diisocyanate, dicyclohexylmethane diisocyanate, tri- Examples include diisocyanate and naphthalene diisocyanate. A preferred diisocyanate is a mixture of 4,4'-diphenylmethane diisocyanate/liquefied MDI (mixed wt ratio) of 80-9515-20.

Preferably, the organic polyisocyanate (A) is a prepolymer obtained by reacting the organic polyisocyanate with a polyol, and the polyol at this time is preferably a polyoxyalkylene polyol, polyoxytetramethylene glycol, and a lactone. Addition-polymerized polyols and the like can be used.

The polyol (B) obtained by addition polymerizing lactone to polyoxytetramethylene glycol used in the present invention is:
Molecular weight 400-10.00 (1, preferably 800-3,
000 polyoxytetramethylene glycol, for example, ε-caprolactone.

- Addition polymerization of lactone such as butyl lactone, valerolactone, etc., preferably 5 to 50% by weight, more preferably 10% by weight
~40% by weight addition polymerization.

However, the addition polymerization rate (wt%) is -, and the total molecular weight of the addition polymerized polyol is 420
~16,000, preferably 715-4,200.

The correlation between the lactone addition rate and the properties of cellular polyurethane elastomers shows that whether the lactone addition rate is less than 5% by weight or greater than 50% by weight, the high crystallinity of the addition polymerized polyol does not decrease and the resistance is significantly increased. This is not preferable because it results in a decrease in flexibility.

If the molecular weight of the addition polymerized polyol becomes extremely small, the elongation and rebound properties of the sole will decrease, making it unsuitable for practical use.

Furthermore, if the size is extremely large, the addition polymerized polyol will have a high viscosity and a high melting point, which will cause problems in the molding operation and molding processability.

A polyoxyalkylene polyol is a compound obtained by adding a cyclic ether such as an epoxide to a polyvalent initiator. Examples of polyvalent initiators include compounds having a hydroxyl group or an amino group, such as polyhydric alcohols, alkanolamines, polyhydric phenols, and mono- or polyamines. As the epoxide, alkylene oxide is most preferred, but halogen-containing alkylene oxide, glycidyl ether, glycidyl ester, styrene oxide, and other three-membered cyclic ethers may be used alone or in combination with alkylene oxide.

As the polyvalent initiator, a compound having a valence of 2 to 8, especially a compound having a valence of 2 to 4 is suitable. Therefore, the high molecular weight polyol is preferably a valent of 2 to 8, especially a compound having a valence of 2 to 4. . A mixed polyoxyalkylene polyol can also be obtained by using a mixture of two or more initiators. Examples of the initiator include the following compounds, and di- to tetrahydric polyhydric alcohols are particularly preferred.

Polyhydric alcohols: ethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, glycerin, trimethylolpropane, pentaerythritol, diglycerin, dextrose, tulpitol, sucrose, polyoxytetramethylene glycol.

Alkanolamines: monoethanolamine, jetanolamine, triethanolamine, diisopropanolamine, N-alkyl jetanolamine.

Amines: ethylene diamine, propylene diamine, tolylene diamine.

Polyhydric phenol: Bisphenol A1 novolac.

Epoxides include alkylene oxides, especially those with 2 carbon atoms.
-3 alkylene oxides are preferred.

Particularly preferred is a combination of ethylene oxide and brobylene oxide and/or butylene oxide.

Molecular weight is 260-8000, preferably 1000
~5000.

Other polybutadiene polyols, acrylic polyols, higher fatty acid ester polyols, and the like may also be used in combination as polyols.

Furthermore, as a chain extender, for example, ethylene glycol,
Propylene glycol, butylene glycol, diethylene glycol, bentanediol, hexanediol,
Polyols include compounds having 2 to 4 hydroxyl groups with a molecular weight of 60 to 300, such as bishydroxybenzene, methylenebishydroxybenzene, trimethylolpropane, and pentaerythritol, and mixtures thereof.

Particularly preferred are ethylene glycol, butylene glycol, and diethylene glycol.

Examples of the foam stabilizer used in the present invention include silicone surfactants such as dimethylpolysiloxane, polyoxyalkylene polyol-modified dimethylpolysiloxane,
Althenyl gelicol-modified dimethylpolysiloxane is mentioned, and natural oil-based surfactants include fatty acid carboxylates, fatty acid sulfate ester salts, fatty acid phosphate ester salts, and sulfonate salts (anionic surfactants). A particularly preferred foam stabilizer is alkylene polyether modified silicone surfactant (trade name: 5RX-2).
74C (manufacturer: Nitoray Silicone Co., Ltd.), and funnel oil (manufacturer: Ito Oil Co., Ltd.) obtained by sulfating castor oil and neutralizing caustic soda, preferably from 0.1 to 1.0 per 100 parts by weight of polyol. Parts by weight are added.

In addition to distilled water, blowing agents used in the present invention include fluorocarbons such as trichlorofluoromethane, dichlorofluoromethane, dichlorofluoromethane, trichlorofluoromethane, and trichlorotrifluoroethane.

As the urethanation catalyst used in the present invention, suitable known catalysts include tertiary amines such as triethylamine, tributylamine, triethylenediamine, N-methylmorpholine, N-ethylmorpholine, N-coco-morpholine,
N, N, N', N'-tetramethylethylenediamine,
1,4-diazabicyclo-(2,2,2)-octane,
N-methyl-N'-dimethylaminoethylpiperazine,
N,N-dimethylhensylamine, bis-(N,N-diethylaminoethyl)-acetate, N,N-diethylbenzylamine, pentamethyldiethylenetriamine,
N.

N-dimethylcyclohexylamine, N, N, N', N
Vertetramethyl-1,3-butanediamine, N,
Contains N-dimethyl-β-phenylethylamine, 1,2-dimethylimidazole and 2-methylimidazole.

Organometallic compounds and more particularly organotin compounds may also be used as catalysts.

Preferred organotin compounds are tin mercaptide and tin acetate (
■), silver octoate (■), tin ethylhexanoate (ff
) and tin (n) salts of carboxylic acids such as silver(II) laurate and tin salts such as diptyltin oxide, dibutyltin dichloride, diptyltin diacetate, diptyltin dilaurate, diptyltin simalate and dioctyltin diacetate. (IV) Contains a compound. It is of course also possible to use any of the abovementioned catalysts in the form of mixtures.

When used as a urethane prepolymer as the organic polyisocyanate (A) of the present invention, the following polyhydroxy compounds can be used in addition to the above-mentioned polyol obtained by addition-polymerizing lactone to a polyoxyalkylene polyol. For example, polyoxyalkylene polyol (
Polyoxypropylene glycol, polyoxypropylene triol, polyoxyethylene propylene glycol, polyoxyethylene propylene triol, polyoxytetramethylene glycol, glycol obtained by addition polymerizing alkylene oxide to polyoxytetramethylene glycol, etc.), lactones, polymers (usually , ring-opening polymerization polyols of lactones using glycols as an initiator) are suitable for providing the mechanical strength, water resistance, etc. of cellular polyurethane elastomers.
Other types of polyols such as acrylic polyols, polybutadiene polyols, and polyester polyols may be used in combination, and glycols exemplified as chain extenders may also be used in combination.

The urethane prepolymer is prepared by reacting the above polyhydroxy compound with an organic polyisocyanate.

Further, a urethane prepolymer containing unreacted polyisocyanate is usually called a urethane semi-prepolymer, and may be used as an isocyanate component for shoe soles.

The NCO equivalent of the urethane prepolymer is preferably 26
0 to 1,800, particularly preferably 260 to 500.

The polyurethane elastomer of the present invention uses, as a polyol component, a polyol (B) obtained by addition polymerizing lactone to polyoxytetramethylene glycol alone, or a polyoxyalkylene polyol is used in combination with the polyol (B). In this case, polyoxyalkylene polyol 0~
It is preferable to use the polyol (B) at a weight ratio of 40 to 100 to 60.

When a prepolymer is used in the present invention, the production method requires an equivalence ratio between the isocyanate component and the polyol component.
a/b, ≧2.1 and/or a/bl +b
, ≧2.1 Furthermore, the following relationship holds true for the equivalent ratio of each component during the reaction of the two-component cellular polyurethane elastomer.

In the above formula, □〈2.1　and It is not suitable for practical use because it has a high molecular weight and high viscosity.

Since the molecular ends of polyurethane elastomers theoretically become OH groups, it is difficult for urethane-specific crosslinking reactions such as allophanate bonds and billet bonds to proceed, and the molecular weight of polyurethane is also relatively small. Because of the upper NGO groups, urethane-specific crosslinking reactions such as allophanate bonds and billet bonds tend to proceed, but when the NGO excess ratio falls within this range, the linear polyurethane molecular weight does not increase and the balance of strength and elongation is poor.

The composition of the present invention is formed into a shoe sole by conventional methods.

The molded sole has a density of 0.3 to 1.0 g/cI113
, preferably 0.4 to 0.7 g/cm'.

(Example) Next, the present invention will be described in detail by giving examples, comparative examples, etc. "Parts" and "%" written therein are "parts by weight",
shall mean "% by weight".

Synthesis Example 1 Polyoxytetramethylene glycol (OH value 56.0
, acid value 0.1) 90 parts, ε-caprolactone 10 parts
Addition polymerization was carried out for 3 hours at 50 to 200° CXI (Lacto 710% addition polymerization polyol No.

To-2000-10, OHHSO35, acid value 0.5)
After that, at 60°C, 3.8 parts of ethylene glycol, 0.7 parts of diethylene glycol, Silicone S RX-274C
0.5 parts, triethylenediamine 0.8 parts, distilled water 0.
Polyol compound To-30- with addition of 53 parts
1 was adjusted.

Synthesis Example 2 Polyoxytetramethylene glycol (OH value 56.0
, acid value 0.1) and 20 parts of ε-caprolactone were subjected to addition polymerization at 150 to 200°C for 1 to 3 hours (lacto 720% addition polymerized polyol NαTo-2000-2).
0, OH value 46.2, acid value 0.55), 4.0 parts of ethylene glycol, 0.0 parts of diethylene glycol at 60°C.
Polyol compound No. To-30-2 was prepared by adding 7 parts of silicone SRX-274C, 0.5 parts of silicone SRX-274C, 0.8 parts of triethylenediamine, and 0.53 parts of distilled water.

Synthesis Example 3 Polyoxytetramethylene glycol (OH value 56.0
, acid value 0.1), 60 parts of ε-caprolactone, 1
Addition polymerization was carried out at 50-200° CXI for 3 hours (lacto 740% addition polymerized polyol To-2000-40,
OHHBO26, acid value 0.5), at 60°C, 4.4 parts of ethylene glycol, 0.8 parts of diethylene glycol, 0.5 parts of silicon SRχ-274C, 0.8 parts of triethylenediamine, and 0.53 parts of distilled water. The added polyol compound To-30-3 was prepared.

Synthesis Example 4 Polyoxytetramethylene glycol (OH value 172.
5, acid value 0.1) 68.9 parts, polyoxytetramethylene glycol (OH value 37.3, acid value 0.1) 11.
1 part and 20 parts of ε-caprolactone at 150-200°C
Addition polymerization was carried out for ~3 hours (lacto 720% addition polymerization polyol k To-650/3.000-20, OH
value 46.2, acid value 0.55), at 60°C, 4.0 parts of ethylene glycol, 0.7 parts of diethylene glycol,
Polyol compound No. To-30-4 was prepared by adding 5 parts of 7SRX-274CO, 0.8 parts of triethylenediamine, and 0.53 parts of distilled water.

Synthesis Example 5 Polyoxytetramethylene glycol (OH value 37.3
, acid value 0.1) 90 parts, ε-caprolactone 10 parts
Addition polymerization was carried out for 50 to 200° CXI for 3 hours (lacto 710% addition polymerized polyol To-3000-10,
08 value: 33.5, acid value: 0.5), 4.7 parts of ethylene glycol, 0.8 parts of diethylene glycol, 0.5 parts of silicone S RX-274C, 0.8 parts of triethylenediamine, 0.0 parts of distilled water at 60°C. A polyol compound To-30-5 was prepared with the addition of 53 parts.

Synthesis Example 6 Polyol NαTo-2000-10 shown in Synthesis Example 1
(OHHSO35, acid value 0.5) 43.95 parts, 4
．． 4'-diphenylmethane diisocyanate 47.6
4 parts and 8.41 parts of liquefied MDI (Japan Polyurethane Industries, Millionate MTL) at 60-90°C x 15-
After reacting for 180 minutes, urethane prepolymer No., To
-31-1 (NGO equivalent weight 250) was prepared.

Synthesis Example 7 Polyoxypropylene glycol (PPG 2000
) (OH value 56.0, acid value 0.1) 36.84 parts,
1.06 parts of dipropylene glycol, 52.78 parts of 4.4'-diphenylmethane diisocyanate and liquefied M
9.32 parts of DI was reacted at 60 to 90°C for 15 to 180 minutes to form urethane prepolymer NαTo-31-2 (N
CO equivalent weight 230) was adjusted.

Reference example 8 Polyoxyethylene propylene glycol (08 value 43
．． 1, acid value 0.1, EO addition rate 20%) 75 parts, polyoxyethylene propylene triol (OH value 36.5,
acid value 0.1, EO addition rate 20%) 25 parts, ethylene glycol 6.5 parts, diethylene glycol 0.5 parts, silicon S RX-274C 0.5 parts, distilled water 0.57 parts,
A polyol compound To-30-6 containing 0.8 parts of triethylenediamine was prepared in a rich sieve.

Reference Example 9 Boreethylene butylene adipate (o[1fi55.
6, acid value 0.5) 100 parts, ethylene glycol 8.0
part, Silicon S RX-274C0.5 parts, distilled water 0
．． A polyol compound To-30-7 containing 54 parts of polyol and 0.5 parts of triethylenediamine was prepared.

Reference example 11 Polyethylene/diethylene adipate (OH value 55.6
, acid value 0.5) 39.57 parts, 4,4'-diphenylmethane diisocyanate 51.37 parts, liquefied MDI
9.07 parts were reacted at 60 to 90°C for 15 to 180 minutes to prepare urethane prepolymer grade To-313 (NGO equivalent: 230).

Reference Example 10 Polycaprolactone glycol (OH value 55.6, acid value 0.5) 100 parts, ethylene glycol 3.8 parts, diethylene glycol 0.7 parts, silicone 5RX-274C
0.5 parts, distilled water 0.54 parts, triethylene diamiso 0
．． Polyol compound To-30- containing 5 parts
8 was adjusted.

Examples 1 to 6, Comparative Examples 1 to 3 The polyol and urethane prepolymer obtained in the above reference example were molded with the formulation shown in Table 1 under the following molding conditions to obtain a molded product, and its physical properties were evaluated. The results are shown in Tables 1 and 2.

The molding conditions for the two-component cellular polyurethane elastomer of the present invention are as shown below.

■Foaming machine used: Automatic mixing injection foaming machine, automatic mixing injection foaming machine, high-pressure reaction injection foaming machine (RIM) Any of these can be used.

■Mixing temperature Polyisocyanate (urethane prepolymer) component 35-45°C Polyol (polyol compaland, etc.) component 35-45°C ■Reactivity Cream time (CT) 5-10 seconds Rise time (RT) 30-60 seconds Tack Free time (TPT) 30 to 60 seconds ■Mold Mold temperature 40 to 50°C Demoulding time 4 to 6 Separation agent Silicone and wax ■Density Free form density 0, 30 to 0.35 g / Cl11" molded product Density 0, 60 +0.02 g/cm3 ■Aging conditions for molded products Approximately 1 week at room temperature Using the molded products obtained on each side above, normal physical properties (hardness, tensile strength, elongation at break, tear strength, Senpo bending test) ) Water resistance (8
Sampled from a 0°C x 95% RH constant temperature and humidity chamber,
After leaving for 4 hours or more, hardness, tensile strength, elongation at break, and senpo-type bending test) were measured. The results are shown in Table 1.

In addition, various test methods are as shown below.

■ O hardness of ASKER-C: Compliant with 5RIS-0101 (6mm thickness) Q N JIS-A: J
Based on IS-6301 (〃) O tensile strength (JIS 3
No. dumbbell): (〃) ○ Breaking elongation (JIS No. 3 dumbbell): Compliant with JIS-6301 (6an thickness) O tear strength (B type dumbbell): Compliant with JIS-6301 (〃) O Senbo Type bending test (10mm thickness)
Angle 90°, 20ORPM, load ib.

The Texon paper on the back was attached to a test piece (25.4 x 150 x 10 t mm). However, for the normal test, a test piece with a 2.0 mm notch was used, and for the post-water resistance test, a test piece was used without a 2.0 mm notch.

(Effects of the present invention) The two-component cellular polyurethane elastomer composition for shoe soles of the present invention has both mechanical strength (tensile strength, tear strength, etc.) and water resistance, and also has excellent bending resistance and Because it has excellent abrasion and crack resistance, it is suitable for the soles of sports shoes for jogging and tennis, high-quality men's leather shoes, safety shoes, etc.

Agent Patent Attorney Katsutoshi Takahashi

Claims (1)

[Scope of Claims] 1. A two-component cellular polyurethane elastomer composition for shoe soles comprising (A) an organic polyisocyanate (B) a polyol obtained by addition polymerizing lactone to polyoxytetramethylene glycol. 2. The composition according to claim 1, wherein the organic polyisocyanate (A) is a prepolymer obtained by reacting a polyol with an organic polyisocyanate. 3. The composition according to claim 1, wherein the lactone addition rate of the polyol (B) is 5 to 50% by weight. 4. A shoe sole comprising the composition of claim 1.