WO1999067313A1

WO1999067313A1 - Process for producing polyurethane foam

Info

Publication number: WO1999067313A1
Application number: PCT/JP1999/003296
Authority: WO
Inventors: Akito Itoi; Koei Hosokawa; Yasutoshi Isayama; Atsushi Ishikawa
Original assignee: Kao Corporation
Priority date: 1998-06-22
Filing date: 1999-06-21
Publication date: 1999-12-29
Also published as: JP3589423B2; CN1122058C; ID28836A; MY128201A; CN1306549A

Abstract

A process for producing a polyurethane foam which comprises reacting: an isocyanate composition (ingredient A) containing an isocyanate-terminated prepolymer obtained by condensation-polymerizing a polyester polyol resulting by reacting a polybasic acid ingredient comprising an aromatic polybasic acid and an aliphatic polybasic acid in a molar ratio of 0.05 to 0.4 with a polyhydric alcohol ingredient and a polyether polyol having two to six functional hydroxyl groups on the average and a number-average molecular weight of 1,500 to 20,000 with an organic polyisocyanate; with a polyol ingredient (ingredient B) comprising a polyester polyol or polyether polyol, a chain extender, a foaming agent, and a catalyst for urethane formation. By the process, a polyurethane foam which has excellent mechanical strength, is significantly reduced in the development of pinholes or shrinkage marks on the surface, and is suitable for use especially as a shoe sole can be produced in a short demolding time.

Description

Description Manufacturing method of polyurethane foam Technical field

The present invention relates to a method for producing a polyurethane foam. More specifically, the present invention relates to a method for producing a polyurethane foam having high mechanical strength and suitably used as shoe soles and the like. Background art

Conventionally, as a method for producing a low-density polyurethane foam having good dimensional stability and small shrinkage, an isocyanate obtained by reacting a polyester polyol with a specific polyether polyol with an organic polyisocyanate is used. A method using a prepolymer has been proposed [Japanese Unexamined Patent Publication (Kokai) No. 2-105584].

However, in this method, since a polyether polyol component is used for a part of the prepolymer, the polyurethane foam is removed from the molding die in comparison with the method using an isocyanate prepolymer obtained only from the polyester polyol. In addition, the polyurethane foam obtained has a disadvantage in that the time required for removal (demolding time) is prolonged and the productivity is reduced, and a decrease in mechanical strength is observed in the obtained polyurethane foam.

As a method for producing a polyurethane foam having excellent mechanical strength, there has been proposed a method using a polyester polyol having a molar ratio of terephthalic acid component Z fatty acid polybasic acid of 0.05 to 0.3 as a raw material. [Japanese Unexamined Patent Publication No. Hei 9-310265]. According to this method, a polyurethane foam having excellent mechanical strength can be obtained. In recent years, however, a polyurethane foam having less shrinkage and more excellent dimensional stability has been developed. Is eagerly awaited. An object of the present invention is to produce a polyurethane foam which has excellent mechanical strength, has very few pinholes and shrinkage on the surface, and is particularly suitable for use as a polyurethane foam for shoe soles in a short demolding time. It is to provide a method that can do this.

The above and other objects of the present invention will become apparent from the following description. Disclosure of the invention

According to the present invention,

A method for producing a polyurethane foam by reacting the following components A and B,

(A component) A polyester polyol obtained by polycondensation of a polybasic acid component and a polyhydric alcohol component having a molar ratio of aromatic polybasic acid / aliphatic polybasic acid of 0.5 to 0.4. An isocyanate composition containing an isocyanate-terminated prevolimer obtained by reacting an organic polyisocyanate with a polyether polyol having an average hydroxyl functional group number of 2 to 6 and a number average molecular weight of 1500 to 2000 ( B component) polyester polyol or polyether polyol, and chain extender

A polyol component containing a foaming agent and a urethanation reaction catalyst

Is provided. BEST MODE FOR CARRYING OUT THE INVENTION

"Isocyanate-terminated prepolymer" (hereinafter, simply referred to as "prepolymer") used in the component A means a reaction product of a polyisocyanate and a polyol which does not contain a free hydroxyl group. The prepolymer is a polyisocyanate in a relative amount such that no free hydroxyl groups remain in the prepolymer (indicated by the number of isocyanate groups per hydroxyl group present in the reaction mixture, and so on). It is obtained by reacting a nate with a polyol. This relative amount is preferably 2 or more so that no free hydroxyl groups remain in the prepolymer. If the relative amount is greater than 2, free polysocyanate, ie, polysocyanate that has not reacted with the polyol, may remain. This free polyisocyanate affects the NC% of the A component isocyanate composition. The relative amount is preferably 50 or less, more preferably 30 or less, from the viewpoint of storage stability and liquidity at room temperature.

The “average number of hydroxyl functional groups” means the average number of functional groups of the polyol composition (1) assuming that the average number of active hydrogens per molecule of the starting materials used in the production is the average number of functional groups of the starting materials. Number of hydroxyl groups per molecule), but in practice is somewhat lower due to terminal unsaturation. Also, the “number of hydroxyl functional groups” indicates the number of hydroxyl groups per molecule.

The "isocyanate composition" used for the component A may contain free polysocyanate in addition to the prepolymer.

The polyester polyol in the component A is obtained by polycondensation of a polybasic acid component and a polyhydric alcohol component, and the molar ratio of the aromatic polybasic acid / aliphatic polybasic acid of the polybasic acid component is 0.05 to 0.4.

Examples of the aromatic polybasic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, fluoric anhydride, and 0-fluoric acid;

(In the formula, R ¹ is an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aryl alkyl group having 7 to 13 carbon atoms, a halogen atom, an alkoxy group having 1 to 4 carbon atoms, A hydroxyl group or an aryloxy group having 6 to 12 carbon atoms which may have a substituent; A phthalic acid derivative represented by the formula:

Wherein R ² is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 12 carbon atoms, an arylalkyl group having 7 to 13 carbon atoms, a halogen atom, Or an aryloxy group having 6 to 12 carbon atoms which may have an alkoxy group, a hydroxyl group or a substituent which may have a substituent.) A mixture of more than one species can be used. Among these aromatic polybasic acids, aromatic dicarboxylic acids, 4-methylfuranic anhydride, 1,4-naphthalenedicarboxylic acid and 2,6-naphthalenedicarboxylic acid can be preferably used. Of these, terephthalic acid, phthalic anhydride and 0-fluoric acid are particularly preferred.

Aliphatic polybasic acids include, for example, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, nonamethylenedicarboxylic acid, decamethylenedicarboxylic acid, pendeca Methylene dicarboxylic acid, dodecamethylene dicarboxylic acid, tridecamethylene dicarboxylic acid, tetradecamethylene dicarboxylic acid, pendecamethylene dicarboxylic acid, hexadecamethylene acid, nonadecamethylene dicarboxylic acid, icosamethylene dicarboxylic acid, henicosamethylene dicarboxylic acid Saturated aliphatic dicarboxylic acids such as acid, docosamethylene dicarboxylic acid, tetracosamethylene dicarboxylic acid, octacosamethylene dicarboxylic acid, dotriacontamethylene dicarboxylic acid, maleic acid, fumaric acid, itaconic acid Unsaturated aliphatic dicarboxylic acids, dimer acids, Kuen acid, tartaric acid, spiculisporic acid and the like, and these aliphatic polybasic acids can be used alone or two or more of them combined mixed. Among these fatty acid-resistant polybasic acids, saturated fatty acid-resistant Rubonic acid, and also adipic acid, can be suitably used from the viewpoint of imparting excellent hydrolysis resistance and tensile strength to the obtained polyurethane foam in a well-balanced manner, and being highly safe and inexpensive. It is.

The polybasic acid component used in the present invention contains an aromatic polybasic acid and an aliphatic polybasic acid, but contains other polybasic acid components as long as the object of the present invention is not impaired. It may be. Examples of the other polybasic acid component include halogen-containing dicarboxylic acids such as tetrabromophthalic acid.

In the above-mentioned polybasic acid component, the molar ratio of aromatic polybasic acid / aliphatic polybasic acid is set so that the solidification point is not increased, and a liquid is formed under molding conditions (molding temperature: about 40 to 50 ° C). In order to exhibit the above, it is desirable to set it to not less than 0.05, preferably not less than 0.08, and from the viewpoint of facilitating injection and injection at the time of molding, it is preferably not more than 0.4, more preferably not more than 0.08. It is desirable to be 2 or less.

Examples of polyhydric alcohol components include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-propanediol, 1,4-butanediol, 1,5-pentenediol, and neopentyl. Glycol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, diethylene glycol, and the like. The dihydric alcohol components can be used alone or in combination of two or more. Among these polyhydric alcohol components, ethylene glycol and 1,4-butanediol can be suitably used from the viewpoint of obtaining a polyurethane foam having physical properties such as excellent tensile strength. Ethylene glycol and 4-butanediol may be used alone or in combination.

The polyester polyol is obtained by polycondensing a polybasic acid component and a polyhydric alcohol component.

The reaction between the polybasic acid component and the polyhydric alcohol component is a condensation polymerization reaction. Since both ends of the ester polyol are always hydroxyl groups, the stoichiometric ratio of the COOH group of the polybasic acid component to the OH group of the polyhydric alcohol component (C〇OH / OH) is more than 1. Preferably, it is slightly smaller.

The method of polycondensing the polybasic acid component and the polyhydric alcohol component is not particularly limited as long as it is a method usually employed when producing a polyester. From the viewpoint of workability, the polyester polyol obtained by polycondensation of the polybasic acid component and the polyhydric alcohol component preferably exhibits a liquid state at 40 ° C., and has a degree of restriction at 60 ° C. of 1 0 0 0 O m P a · s or less can be used ο

The polyether polyol used for the component A has an average number of hydroxy functional groups of 2 to 6 and a number average molecular weight of 1500 to 2000. The average number of hydroxyl functional groups is set to 2 or more from the viewpoint of preventing the progress of molecular growth and deterioration of physical properties, and is 6 or less, preferably 4 or less, from the viewpoint of improving the flexibility of the polyurethane foam. Preferably it is 3 or less. The number average molecular weight is set to 1500 or more from the viewpoint of hardly shrinking the polyurethane foam, and is set to 2000 or less from the viewpoint of shortening the demolding time.

Examples of polyether polyols include polyoxypropylene-based polyols having a number average molecular weight of 150 or more per hydroxyl group in which ethylene oxide is added to terminal hydroxyl groups of polyoxypropylene polyol (hereinafter referred to as PPG). ), Polyoxytetramethylene glycol (hereinafter referred to as PTMG) having a number average molecular weight of i500 or more obtained by ring-opening polymerization of tetrahydrofuran, and mixtures thereof.

PPG can be suitably used because it has a long repeating unit of an oxypropylene chain, and thus works effectively as a soft segment in the obtained polyurethane foam, and plays a role of improving elongation characteristics and bending characteristics. Things. In PPG, the molecular weight per hydroxyl group is calculated as the soft segment of the oxypropylene chain. From the viewpoint of effectively expressing all the roles, it is more than 1500, preferably more than 2000, more preferably more than 300, and from the point of viscosity of handling, less than 200, It is preferably at most 1500, and more preferably at most 800.

PPG is produced by using a compound having two or more active hydrogens as a starting material, subjecting it to a conventional ring-opening addition reaction of an alkylene oxide, and further adding ethylene oxide to the molecular terminals in a block-like manner. Can be.

Starting materials for PPG include polyhydric alcohols, polyphenols, polyamines, alkanolamines and the like. Specific examples thereof include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane, pennoerythritol, Examples include glycerin, dextrose, sucrose, bisphenol A, ethylenediamine, denatured products thereof, and the like. These can be used alone or in combination of two or more.

Examples of the alkylene oxide to be subjected to the ring-opening addition reaction to the starting material include ethylenoxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, and styrene oxide. Among them, propylene oxide may be used alone, or propylene oxide may be used as a main component (50% by weight or more), and may be used in combination with other alkylene oxides so as to perform random copolymerization or block copolymerization. Is preferred.

After the reaction between the starting material and the alkylene oxide, a blockwise addition reaction of ethylene oxide is performed so that the terminal hydroxyl group becomes primary in order to increase the reactivity of urethanization in producing a polyurethane foam. Is preferred. The primary hydroxylation ratio of terminal hydroxyl groups by ethylene oxide (the number of primary hydroxyl groups / the total number of hydroxyl groups) increases the reactivity of urethanization in the production of polyurethane foam, shortens the demolding time, reduces resinification speed and reduces foaming. Polyurethane foam shrinks by improving the balance of From the viewpoint of preventing generation, it is preferably at least 50%, more preferably at least 70%.

By the way, when the content of the oxechylene group present inside and at the terminal of the PPG is increased, the hydrophilicity is increased, water is attracted, and the hydrolysis resistance is reduced, so that the content of the oxyethylene group in the PPG is increased. The amount is preferably 35% by weight or less, and from the viewpoint of the primary hydroxyl group termination ratio, the content of oxyethylene groups in PPG is preferably 5% by weight or more. Note that PPG may be composed of several types of polyoxyalkylene polyols as long as the molecular weight per hydroxyl group, the content of oxethylen groups, and the primary hydroxylation ratio of terminal hydroxyl groups in the polyether polyol as a whole are within the above ranges. May be mixed and prepared.

The PTMG has a property of improving mechanical properties such as strength from its molecular structure. The number average molecular weight of PTMG is 150 or more, preferably 180 or more, from the viewpoint of the usefulness of the oxytetramethylene chain as a soft segment, and the point that the liquidity is maintained at the handling operation temperature. From this, it is set to not more than 2000, preferably not more than 3000, more preferably not more than 230.

Specific examples of the organic polyisocyanate used for the component A include tolylene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, xylylene diisocyanate, and 4,4 'diphenyl. Enylmethanediisocyanate, hexamethylenediisocyanate, isophoronediisocyanate, polymethylenepolyphenyldiisocyanate, 3,3'-dimethyl-4,4'-biphenyldienediisocyanate, 3,3'-Dimethyl-4,4 'diphenylmethane diisocyanate, 3,3-dichloro-1,4,4'-biphenylenediisocyanate, 1,5-naphthyl diisocyanate Examples thereof include cyanate compounds and modified products thereof, for example, modified products of carposimid. These organic polysocyanate monomers may be used alone. Or it can be used as a mixture of two or more. Among them, 4,4 'diphenylmethane diisocyanate is used alone or It is particularly preferable to use the 4,4′-diphenylmethane diisocyanate in combination with its modified carpoimide.

The isocyanate composition of component A is obtained by reacting an organic polyisocyanate with a mixture of a polyester polyol and a polyether polyol, or by reacting a polyester polyol and a polyether polyol in order or in any order. Can be prepared. Further, a polyester isocyanate composition containing a polyester prepolymer obtained by reacting a polyester polyol and an organic polyisocyanate, and a polyether prepolymer obtained by reacting a polyether polyol with an organic polyisocyanate. May be used in admixture with the polyether-based isocyanate composition. The polyester-based isocyanate composition and the polyether-based isocyanate composition may each contain a free organic polyisocyanate. The polyester polyol “polyether polyol (weight ratio) is preferably 1/9 to 9/1, more preferably 1 Z 5 to 5/1. Also, the polyester-based isocyanate composition When the polyester polyol and the polyether-based composition are used as a mixture, the polyester polyol Z polyether polyol (weight ratio) calculated by calculation is preferably 1/9 to 9 Z 1, More preferably, it is 5 to 5/1.

When preparing the isocyanate composition of the component A, an additive may be added as necessary.

Examples of the additives include, for example, additives used when preparing the polyester polyol or polyether polyol, and hydrogen chloride gas, sulfurous acid, and sulfuric acid prepolymer to prevent the isocyanate prepolymer from self-polymerizing. Acidic gas such as gas, acid chlorides such as acetyl chloride, benzoyl chloride and isophthalic acid chloride, and isocyanate self-polymerization inhibitor such as phosphoric acid, monoethyl phosphate and phosphoric acid compound such as getyl phosphate can be used. These additives may be used alone or in combination. These can be used in combination.

The NC 0% of the isocyanate composition is desirably 15% or more, preferably 17% or more, in order to prevent the viscosity from increasing so that molding with a low-pressure foaming machine becomes difficult. From the viewpoint of avoiding a decrease in the measuring accuracy of the foaming machine, the content is desirably 25% or less, preferably 22% or less.

As the polyester polyol or polyether polyol as the component B, those having an average number of hydroxyl functional groups of 2 to 6 and a number average molecular weight of 500 to 600 are preferable. Examples of polyester polyols include ethylene glycol, ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, methylpentanediol, 1,6-hexanediol, trimethylolpropane, glycerin, At least one polyhydric alcohol such as pentaerythritol, diglycerin, dextrose, sorbitol, and at least one dibasic such as oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, dimer acid, etc. Examples thereof include polyester polyols and polyproprolactone polyols obtained by polycondensation with an acid, and the polyester polyols may contain a polyester polyol or a polycarbonate polyol used as the component A. Examples of the polyether polyol include polyether polyols such as polypropylene glycol and polyoxytetramethylene glycol, and the polyether polyol may contain the polyether polyol used in the component A. The polyester polyol and the polyether polyol can be used alone or in combination of two or more. Among them, from the viewpoint of improving the physical properties, a polyester polyol obtained by condensation-polymerizing ethylene glycol and 1,4-butanediol with adipic acid or ethylene glycol and diethylene glycol with adipic acid is preferable.

As the chain extender used for the component B, a polyol having 2 to 6 hydroxyl functional groups and a molecular weight of 62 to 499 is preferable. 2 or more hydroxyl functional groups With, sufficient release properties and physical properties can be obtained, and when it is 6 or less, flexibility is improved. When the molecular weight is in this range, the demolding time is further shortened. The amount thereof is preferably 2 to 30 parts by weight, more preferably 5 to 25 parts by weight, per 100 parts by weight of the polyester polyol or polyether polyol from the viewpoints of demolding properties and physical properties.

Representative examples of chain extenders include ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentenediol, methylpentenediol, and 6-hexanediol, trimethylethylpropane, Polyhydric alcohols such as glycerin, pen erythritol, diglycerin, dextrose, and sorbitol; aliphatic polyamines such as ethylenediamine and hexamethylenediamine; aromatic polyvalent amines; and jetanolamines And alkanolamines such as triphenylamine, diisopropanolamine and the like. These chain extenders can be used alone or in combination of two or more.

Examples of the foaming agent include water, fluorocarbons such as trichlorofluoromethane, dichlorodifluoromethane, and trichlorodifluoroethane, as well as water.These foaming agents may be used alone or in combination of two or more. O Can be mixed and used

Examples of urethanization catalysts include triethylamine, triethylenediamine, N-methylmorpholin, N-ethylmorpholin, N, N, N ', N'-tetramethylhexamethylenediamine, and 1,2-dimethylimidazo. Tertiary amines such as octyl, N, N'-ethyl pentylamine, tin (II) acetate, tin (II) octoate, tin (II) laurate, dibutyltin dilaurate, dibutyltin dimaleate, octyltin Examples include tin compounds such as diacetate and dibutyltin dichloride. These urethanization catalysts can be used alone or in combination of two or more.o

The B component may contain a foam stabilizer, a stabilizer, a pigment, and the like in appropriate amounts as necessary. Examples of the foam stabilizer include silicone surfactants such as dimethylpolysiloxane, polyoxyalkylenepolyol-modified dimethylpolysiloxane, and alkyleneglycol-modified dimethylpolysiloxane, fatty acid salts, sulfate salts, phosphate ester salts, and the like. Anionic surfactants such as sulfonic acid salts are exemplified.

Examples of the stabilizer include dibutylhydroxytoluene, penyu erythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) probionet], isooctyl-3- (3,5-di- hindered phenolic radical scavengers such as t-butyl-4-hydroxyphenyl) propionate; antioxidants such as phosphites such as phosphorous acid, triphenylphosphite, triethylphosphite, and triphenylphosphine; (5-Methyl-2-hydroxyphenyl) benzotriazole, methyl-3- [3-t-butyl-5- (2H-benzotriyl-2-yl) -1-hydroxyphenyl] propionate and boron UV absorbers such as condensates with ethylene glycol, and the like.

Examples of the pigment include an inorganic pigment typified by a transition metal salt, an organic pigment typified by an azo compound, and carbon powder, but the present invention is not limited to only these examples.

Since both the A component and the B component are liquid at 40 ° C., they are suitably used, for example, at a molding temperature of about 40 to 50 ° C. without any problem when producing polyurethane foam. Is what you can do.

In the present invention, the component A and the component B are mixed and stirred by a molding machine at a mixing ratio in which the equivalent of the isocyanate in the component A and the equivalent of the hydroxyl group reacting with the fusocyanate in the component B and the equivalent of water are calculated. The polyurethane foam can be molded by injecting into a molding die and foaming. More specifically, for example, foaming machines such as an automatic mixing injection foaming machine and an automatic mixing injection foaming machine after adjusting the temperature of the component A and the component B to about 4 TC using a tank or the like, respectively. Polyurethane foam can be formed by reacting A component and B component using Wear.

After the component A and the component B are mixed, the mixture can be formed into a molded product such as a shoe sole or the like by using a molding die whose temperature is usually controlled to about 40 to 60 ° C.

Thus, the molded article density of the polyurethane foam obtained by the production method of the present invention is 0.15 to 1.0 g / g from the viewpoint that sufficient mechanical strength is obtained and the density is reduced. It is practical to have a cm ³ , preferably between 0.2 and 0.6 g / cm ³ . Production Example 1 (Production of polyester polyols A to G)

After charging the aliphatic polybasic acids, aromatic polybasic acids, and polyhydric alcohols of the types and amounts shown in Table 1 into a four-necked flask, a stir bar, a dehydrating tube, a nitrogen gas introducing tube, and a thermometer are installed. The flask was attached.

Next, nitrogen gas was introduced into the flask, the generated water was distilled off, and the temperature was raised to 220 ° C.

After confirming that the contents in the flask became transparent, the pressure was gradually reduced, and water was further distilled off.

By continuing the reaction until the acid value of the obtained reaction solution became 1 KOH mg / g or less, polyester polyols A to G shown in Table 1 which were in a liquid state at 40 ° C. were obtained.

As physical properties of the obtained polyester polyols A to G, an acid value, a hydroxyl value, a viscosity, a freezing point and a number average molecular weight were examined. The results are shown in Table 1.

The acid value was measured according to JIS K0070, the hydroxyl value was measured according to JIS K0070, the viscosity was measured according to JIS Z 8803, and the freezing point was measured according to JIS K0065. The number average molecular weight was calculated from the hydroxyl value. table 1

(note)

EG: Ethylene glycol

1, 4-BD: 1, 4-butanediol Production Example 2 (Production of A component 1 16)

In a four-necked flask, 4,4'-diphenylmethane diisocyanate was charged, the temperature was adjusted to 60 ° C, and a stir bar, a dehydration tube, a nitrogen gas inlet tube, and a thermometer were attached. Next, while vigorously stirring the contents in the flask, one of the polyester polyols AG shown in Table 1 obtained in Production Example 1 was gradually dropped at 60 ° C in a nitrogen stream, and The reaction was performed for 2 hours while maintaining the temperature at 6070 ° C.

Next, Karposimid-modified MDI (manufactured by Nippon Polyurethane Co., Ltd., trade name: Coronate MX) was added to the flask, and the mixture was aged for 1 hour to obtain an isocyanate composition having the composition shown in Table 2. Was. Physical properties of the obtained isocyanate composition See Table 2.

The NCO% was measured according to ASTM-D 1638-74, and the viscosity was measured according to JIS Z 8803. In addition, the component A (isocyanate composition) 10 described in Table 2 was not able to be prepared because the degree of distortion of the polyester diol G was extremely high and it was not possible to drop it at 40 ° C.

Table 2

A component type 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

4.4'-Diphenyl

^ Cinet 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 (Heavy S part)

E: polyester polyol A B c D A A C E F G A E A A E C

(ffiffi) 37.1 37.1 37.1 37.1 53.4 35.9 37.1 37.1 37.1 37.1 54.0 37.1 78 34 78 54 Polyether polyol EL E EL EL EL EL EL EL EL EL EL

(Heavy fi part) -510 -510 -510 -510 -510 -850 -510 -510 -510 -510

18.5 18.5 18.5 18.5 26.7 17.5 18.5 18.5 18.5 18.5

Polyester polyol /

: Rie terpoliol 2/1 2/1 2/1 2/1 2/1 2/1 2/1 2/1 2/1 2/1 1/0 2/1 1/0 2/1 1 / 0 1/0

(fflffi ratio)

Carbodiimi F denaturation

MD1 (parts by weight) 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 25 NCO% 21.6 21.6 21.6 21.6 18.6 21.6 21.6 21.6 21.6 21.6 18.5 18.5 21.6 21.5 21.6

Viscosity at 40 ° C 210 225 225 220 430 220 260 195 195 245 420 550 200 235 270 Properties C! (MPa-s)

(note)

E-510: Asahi Glass Co., Ltd., trade name (number average molecule S4000, average number of hydroxy functional groups 2.0, with terminal ethylene oxide added)

EL-850: manufactured by Asahi Glass (Co.) ¾, quotient _u name (.. The number average molecular Λ7000 average hydroxy functionality ¾ number 3.0 terminal Echirenokisai de Yes addition)

PTMG-1000: Hodogaya Chemical Industry Co., Ltd., trade name (number average molecule fllOOO. Average number of hydroxy functional groups 2.0. No terminal ethylene oxide added) PTMG-2000: Hodogaya Chemical Industry Co., Ltd., trade name (Number average molecular weight 2000. Average number of hydroxy functional groups 2.0. No addition of terminal ethylene oxide)

T fc—

o Preparation example (Preparation of 8 components 1-3)

Polyester polyol in the amount shown in Table 3 [Raw material monomers: ethylene glycol, diethylene glycol and adipic acid, ethylene glycol diethylene glycol (molar ratio): 1/1, number average molecular weight: 220, average hydroxyl Number of functional groups: 2], ethylene glycol as chain extender [molecular weight: 62, number of hydroxyl functional groups: 2], water as foaming agent, foam stabilizer [silicone foam stabilizer, manufactured by Dow Chemical Company, product name: DC-193], a urethanization reaction catalyst (manufactured by Kao Corporation, trade name: AS-615-60C) and a pigment (manufactured by Union Chemical Co., trade name: P-505). Charged, the temperature was adjusted to 40 ° C, and the mixture was stirred to obtain B component 1-3. Table 3 shows the obtained degree of B component.

The viscosity was measured according to JIS Z 8803. Table 3

Type of B component 1 2 3

B Polyester polyol 100 100 100

Success

Min Ethylene glycol] -yl (chain extender) 13 15 17

of

Water (foaming agent) 0.7 0.9 1.15

Success

Foam stabilizer 0.5 0.5 0.5 0.5 Urethane-forming reaction catalyst 1.5 1.5 1.4

Department

Pigment 5 5 5 Object Viscosity at 40 ° C 2300 2100 2000

(MPa's) Examples 1 to 9

An automatic mixing type injection foaming machine (Polyurethane Engineering Co., Ltd., Model MU-200), which mixes any one of B components 1 to 3 obtained in Preparation Example and one of A components 1 to 7 obtained in Production Example 2. 3 S, Model No. 6- 0 18), foamed under the following molding conditions, and made with a 1 O mm x 100 mm x 30 O mm polyurethane foam sheet and shoe sole forming mold A bottom molded body was produced.

〔Molding condition〕

Mixing temperature: Both the temperature of the isocyanate prepolymer and the polyol component were adjusted to 35 to 45 ° C.

Reactive cream time 5 10 seconds

String time 1 5 3 0 seconds

Rise time 3 5 6 0 seconds

Tack free time 3 0 5 5 seconds

Mold: Mold temperature 4 5 5 5 ° C

Release agent Silicone and Pax

Density: Freeform density 0.1 2 to 32 g / cm ³

Aging condition: 1 week at normal temperature

(Removability)

The demolding time of the molded shoe sole under the above molding conditions (the shortest time that can be taken out without causing scratches on the surface) was measured. The results are shown in Table 4. Next, as the final physical properties of the obtained sheet, the density, hardness, tensile strength (tensile strength), elongation at break and tear strength of the molded article, and appearance of the shoe sole molded article were examined according to the following methods. . The results are shown in Table 4. [Final physical properties of sheet]

Density of the molded body: 1 0 mmx 1 00 mmx 30 0 mm weighed polyurethane foam sheet over bets, measured hardness was divided by the volume ^{30 0 cm 3 (Asker C)} : determined according to SRIS 0101

Tensile strength: Measured according to JIS K 6301 using JIS No. 1 dumbbell

Elongation at break: Measured according to JIS K 6301 using JIS No. 1 dumbbell

Tear strength: Measured in accordance with JIS K 7311

(Appearance of molded shoe sole)

Observe visually and evaluate based on the following evaluation criteria

(A) Evaluation criteria for surface pinholes

◎: No surface pinholes

〇: Almost no pinholes on the surface

X: Surface pinholes are conspicuous or extremely large

(B) Evaluation criteria for shrinkage

〇: No shrinkage

X: There is shrinkage

Table 4

Comparative Examples 1 to 10

A polyurethane foam and a molded shoe sole were produced in the same manner as in Examples 1 to 9, except that the A component 8 to 9 or 11 to 16 obtained in Production Example 2 was used.

The demolding time of the shoe sole molded article, the physical properties of the obtained polyurethane foam sheet, and the appearance of the shoe sole molded article were examined in the same manner as in Examples 1 to 9. Table 5 shows the results.

Table 5

Examples and comparative examples will be considered based on the above results.

In Example 1, as compared with the case where the aromatic polybasic acid is not contained in the polyester polyol used in the component A as in Comparative Examples 1 and 2, or the content thereof is low, the shoe sole molded body The demolding time can be shortened, and the tensile properties and the like in the final physical properties are greatly improved. '

Regarding Examples 2 to 4, the effect of sufficient demolding property, final property and appearance improvement even when the kind of aromatic polybasic acid or the kind of polyhydric alcohol in the polyester polyol used in the component A is changed. Is recognized.

In Examples 5 and 6, the type of polyether polyol used in the component A or the average number of hydroxyl functional groups was changed from Example 1, but sufficient demolding properties, effects of final physical properties and appearance improvement were obtained. Is recognized.

Example 1 in which the A component contains a polyether polyol is a polyether polyol. As compared with Comparative Example 3 which does not contain, there is no pinhole or shrinkage on the surface of the molded article, and the molded article has an excellent appearance.

In Example 5, no pinholes or shrinkage were observed on the surface of the molded article, and the molded article had an excellent appearance as compared with Comparative Example 4 in which the molecular weight of the polyether polyol used as the component A was reduced.

In Example 7 and Comparative Examples 5 and 6, the NCO% of the component A was reduced, but Example 7 had excellent demolding properties and physical properties as compared with Comparative Example 5, and Comparative Example 6 It has an excellent appearance in comparison with. In particular, Example 7 has no surface pinholes.

In Comparative Example 7, in which the polyester polyol in the component A did not contain an aromatic polybasic acid and no polyester polyol was used, the demolding time of the shoe sole was long, the physical properties were poor, and the molded product was poor. There are many pinholes on the surface, shrinkage is observed, and the appearance of the molded product is defective.

Examples 8 to 9 and Comparative Examples 8 to 10 were prepared so that the density of the compact was 0.35 g / cm ³ . Example 8 is superior in hardness and various strengths as compared with Comparative Example 8 in which the component A (isocyanate composition) in which the aromatic polybasic acid was not used was used. In addition, in contrast to Comparative Examples 9 to 10 in which the component A (isocyanate composition) containing no polyether polyol was used, in Examples 8 to 9, pinholes and shrinkage were observed on the surface of the molded body. It has good appearance and excellent physical properties. Industrial applicability

ADVANTAGE OF THE INVENTION According to the manufacturing method of this invention, the demolding time of a molded object can be shortened and productivity can be improved.

Furthermore, according to the production method of the present invention, it is possible to obtain a polyurethane foam having excellent final physical properties such as tensile strength without generating pinholes, shrinkage, etc. on the surface of the molded article. Can be.

Therefore, the polyurethane foam obtained by the production method of the present invention can be suitably used as a polyurethane foam for shoe soles and the like.

Claims

The scope of the claims

1. A method for producing a polyurethane foam by reacting the following components A and B.

(A component) Aromatic polybasic acid Z Polyester polyol obtained by polycondensation of polybasic acid component and polyhydric alcohol component having a molar ratio of aliphatic polybasic acid of 0.05 to 0.4 An isocyanate composition containing an isocyanate-terminated prevolimer obtained by reacting an organic polyisocyanate with a polyether polyol having an average hydroxyl functional group number of 2 to 6 and a number average molecular weight of 1500 to 2000

(Component B) A polyol component containing a polyester polyol or polyether polyol, a chain extender, a foaming agent, and a urethanization reaction catalyst.

2. The process for producing a polyurethane foam according to claim 1, wherein the polyester polyol or polyether polyol used in the component B has an average number of hydroxyl functional groups of 2 to 6 and a number average molecular weight of 500 to 600.

3. The process for producing a polyurethane foam according to claim 1, wherein the chain extender used in the component B is a polyol having 2 to 6 hydroxyl functional groups and a molecular weight of 62 to 499.

4. The amount of the chain extender used in the component B is 2 to 30 parts by weight per 100 parts by weight of the polyester polyol or polyester polyol, and the polyurethane foam according to any one of claims 1 to 3. Manufacturing method.

5. The process for producing a polyurethane foam according to any one of claims 1 to 4, wherein the NC content of the isocyanate composition is 15 to 25% by weight.