KR20090123714A - Low-specific gravity polyurethane foam compositions having superior hydrolysis-proof - Google Patents

Abstract

PURPOSE: A polyurethane foam composition is provided to ensure excellent hardness and elongation, low specific gravity, and good hydrolysis resistance, and to maintain mechanical properties such as tensile strength of polyurethanefoam. CONSTITUTION: A polyurethane foam composition with excellent hydrolysis resistance comprises low-specific gravity beads with density of 0.05~0.2 g/cm^3 and an organic-inorganic hybrid compound represented by chemical formula 1. In chemical formula 1, X is metal oxide having a network structure; Y is an amino group, sulfide group, ester group or ether group; R^1 and R^2 are the same and different and are C1~C18 linear or branched aliphatic alkylene group, alicyclic alkylene group or aromatic group; R^3 is linear or branched aliphatic alkylene group and alicyclic alkylene group; n is the number of an organic compound substituted for metal oxide having a network structure.

Description

Low-specific gravity Polyurethane foam compositions having superior hydrolysis-proof}

The present invention relates to a polyurethane foam composition comprising an organic / inorganic hybrid compound for improving hydrolysis and low specific gravity beads, which not only significantly improved the hydrolysis resistance of the polyurethane foam, It can be used as a foam for bedding, shock absorber, thermal insulation, etc., especially for polyurethane foams, because it has a lower specific gravity than conventional polyurethane foams and is excellent in mechanical properties.

Foam is used in various industries such as furniture, bedding, shock absorbers, sound insulation, thermal insulation, building materials, electrical and electronics industry, footwear industry, and the foams are widely used in chemically foaming rubber or resin, Latexes such as rubber latex, chloroprene latex and styrene butadiene latex are produced by mechanical foaming.

Currently, the most widely used foam materials include EVA (ethylene vinyl acetate) resin foam and polyurethane foam. Polyurethane foam, which is a foam that is in demand in various industrial fields, has excellent shock absorption and functional parts in a wide temperature range. Not only can be easily installed, but also the simultaneous molding with other parts and materials has the advantage of simple production process and excellent properties such as permanent compression reduction and rebound elasticity. However, there are disadvantages in that discoloration occurs, the resistance to water resistance is bad, and the specific gravity is high. Therefore, many studies have been conducted to solve the disadvantages of the polyurethane foam as described above, and in particular, polyurethane products are hydrolyzed by moisture such as air and thus exhibit a serious mechanical property degradation, thereby improving hydrolysis resistance. And the invention has proceeded as follows.

In Korean Patent Laid-Open Publication No. 2006-33035, the yellowing property is improved to some extent by using a post-treatment process or an additive, but there is a problem of insufficient mechanical properties.

In addition, in the known arts such as Korean Patent Application Publication No. 2007-37712, Korean Patent Publication No. 1992-9686, US Patent No. 5,597,942, Japanese Patent No. 2002-13315, and Japanese Patent No. 09208816A, the water resistance of the polyurethane foam In order to improve the degradability, polyols, isocyanates, catalysts, emulsifiers and other additives and foams have been modified to improve the hydrolysis resistance of polyurethane foams, but they have not achieved great results. As such, while the mechanical properties can be continuously maintained, there is an increasing demand for low specific gravity polyurethane foam.

As described above, the present inventors have continually studied to solve the problems of the existing polyurethane foam and the demands of the industry. As a result, a new inorganic hybrid compound is added to improve the hydrolysis resistance of the existing polyurethane foam, and also the foam The present invention seeks to provide a polyurethane foam composition with the addition of low specific gravity beads to reduce its specific gravity.

Low specific gravity polyurethane foam composition excellent in moisture resistance of the present invention for solving the above problems comprises a polyol and an isocyanate prepolymer and the inorganic hybrid compound represented by the formula (1) as the polyol component and further low specific gravity beads It characterized by including the.

In Chemical Formula 1,

X is a metal oxide forming a network structure; ego

Y is an amino group, a sulfide group, an ester group or an ether group including an element including one or two or more lone pairs selected from nitrogen (N), sulfur (S), and oxygen (O); And

R ¹ and R ² is the same as or different from each other, a C ₁ to C ₁₈ straight or branched aliphatic alkylene group, alicyclic alkylene group, or aromatic group; And

R ³ represents a linear or pulverized aliphatic alkylene group or alicyclic alkylene group having a number average molecular weight of 200 to 8,000; n represents the number of organic compounds substituted with a metal oxide having a network structure.

In addition, another aspect of the present invention is to provide a method for producing the polyurethane foam composition.

Polyurethane foam composition of the present invention containing the above-described composition is excellent in mechanical properties such as hardness, elongation, and light weight because of its low specific gravity, and in particular, because of excellent hydrolysis resistance, Otherwise, the mechanical properties such as the tensile strength of the polyurethane foam when it is first manufactured has a long lasting effect.

The present invention will be described in more detail as follows.

The present invention is characterized in that the polyurethane foam composition comprises an inorganic hybrid compound having a formula (1) and a low specific gravity bead.

[Formula 1]

In Chemical Formula 1, X is a metal oxide forming a network structure; And Y is an amino group, sulfide group, ester group or ether group including an element containing one or two or more non-covalent electron pairs selected from nitrogen (N), sulfur (S), and oxygen (O); R ¹ and R ² is the same as or different from each other, a C ₁ to C ₁₈ straight or branched aliphatic alkylene group, alicyclic alkylene group, or aromatic group; And R ³ represents a linear or pulverized aliphatic alkylene group or alicyclic alkylene group having a number average molecular weight of 200 to 8,000; n represents the number of organic compounds substituted with a metal oxide having a network structure.

Referring to the formula 1 in more detail,

X is a metal oxide having a network structure, and the manufacturing method is not specified, but is preferably a metal oxide produced by a sol-gel method and having a network structure having a size of 20 to 200 nm. In more detail, X has a metal oxide network structure represented by Structural Formula 1 as a basic structure.

[Formula 1]

In Structural Formula 1, M is one metal selected from silicon (Si), titanium (Ti), aluminum (Al), zirconium (Zr), and barium (Ba), and O is oxygen.

Y in Formula 1 may include elements such as N, S, and O as an element or compound including an unshared electron pair, and such compounds include amino groups, sulfide groups, ester groups, ether groups, and the like.

R ¹ and R ² is the same as or different from each other, and is a C ₁ to C ₁₈ straight or crushed aliphatic alkylene group, alicyclic alkylene group, or aromatic group.

R ¹ is a C ₁ to C ₁₂ linear or crushed aliphatic alkylene group or alicyclic alkylene group selected from methylene, ethylene, propylene, butylene, hexamethylene, dodecane methylene, cyclohexylene, phenylene and the like Or aromatic groups are preferred. However, the present invention is not limited thereto.

In addition, R ² is

Butylene, hexamethylene, octamethylene, or dodecane aliphatic alkyl group of C ₂ ~ C ₁₈ such as methylene;

C ₄ -C ₁₅ alicyclic alkyl groups such as isophorone, cyclohexylene or isocyanatocyclohexylene; or

It is more preferable to use C ₆ -C ₁₅ aromatic alkyl groups such as phenylene, naphthalene, diphenylmethyl or toluylene. However, the present invention is not limited thereto.

R ³ is a linear or pulverized aliphatic alkylene group or alicyclic alkylene group having a number average molecular weight of 200 to 8,000, which is a saturated hydrocarbon or an unsaturated hydrocarbon, and further selected from ester groups, ether groups and carbonate groups in the main chain. Further comprising a functional group of the species can be used. And n is an integer having 1 or more, more preferably 1 to 10 ¹⁰ , and represents the number of organic compounds substituted with a metal oxide having a network structure. Here, n is to indicate that each reacting compound reacts in the same molar ratio, and also increases the amount of the reactants does not increase the size of the final product indefinitely.

Hereinafter, a method for preparing the inorganic hybrid compound represented by Chemical Formula 1 will be described in detail.

[Manufacturing method of organic / inorganic hybrid compound]

The inorganic hybrid compound of the present invention represented by Chemical Formula 1 may be prepared through the following 1-3 steps.

결합의 망상 구조를 갖는 금속 산화물의 합성 [Stage 1] :

Synthesis of Metal Oxides Having a Network Structure of Bonds

결합의 망상구조를 갖는 금속 산화물은 하기 반응식 1과 같은 방법 으로 제조할 수 있으며, 이를 상세하게 설명을 하면,

Metal oxides having a network of bonds may be prepared by the same method as in Scheme 1 below.

결합의 망상구조를 갖는 금속 산화물을 합성한다.First, a catalyst and water are hydrolyzed by adding a catalyst and water to a metal alkoxide and an alcoholic silane compound having a compound Y containing a non-covalent electron pair such as a mercapto group, an amino group, an alcohol group, a carboxyl group, and an epoxy group which can react with an isocyanate at the terminal. Substituted alkoxide group with hydroxy (OH) group, and then through the condensation process of M-OH represented by the following formula (2)

A metal oxide having a network of bonds is synthesized.

At the time of preparation, the reaction temperature is 25 ~ 60 ℃ and stirred for 24 hours to terminate the reaction. As the catalyst used herein, strong acids such as hydrochloric acid, sulfuric acid, nitric acid, weak acids such as acetic acid and phosphoric acid may be used, or basic catalysts such as potassium hydroxide, sodium hydroxide, and amine may be used.

In Formula 2, R ¹ is a C ₁ ~ C ₁₈ straight or crushed aliphatic alkylene group, alicyclic alkylene group or aromatic group. Y is an amino group, a sulfide group, an ester group, or an ether group containing an element containing an unpaired or two or more lone pairs selected from nitrogen (N), sulfur (S), and oxygen (O).

In Reaction Scheme 1, M is a metal selected from silicon, titanium, aluminum, zirconium and barium, m is an integer of 0 or more, n is an integer of 1 or more, and R ⁴ is a C ₁ ~ C containing a hydrogen atom ₈ is an alkyl group or an aryl group. Specific examples include methyl group, ethyl group, butyl group, propyl group, octyl group, phenyl and xylyl group.

)을 X로 표시할 것이며, 상기 화학식 2는

으로 표현할 수 있다.In the present specification, in the formula (2), the network portion of the metal oxide (

) Will be represented by X, and the formula (2)

It can be expressed as

The network structure represented by X is a metal oxide having a size of 20 to 200 nm, and may cause problems in that it does not properly exhibit hydrolysis characteristics when less than 20 nm, and when the size exceeds 200 nm, a polyurethane compound is prepared. When doing so, a problem may occur that the mechanical properties are lowered as an impurity. In addition, the network structure can be controlled by changing the reaction pH, the nature and concentration of the catalyst, the molar ratio of water / metal element, the reaction temperature, which can be confirmed through the examples.

[ Step 2 ] : Synthesis of Organic / Inorganic Hybrid Composite

결합의 망상구조를 갖는 금속 산화물과 디이소시아네이트를 반응시켜서 하기 화학식 3으로 표시되는 이소시아네이트 말단의 유·무기 하이브리드 복합체를 제조한다. Represented by Formula 2 prepared in step 1

A metal oxide having a bonded network structure is reacted with a diisocyanate to prepare an organic-inorganic hybrid composite having an isocyanate terminal represented by the following formula (3).

At the time of preparation, the reaction temperature is 40 to 100 ° C. and stirred for 2 to 4 hours until the YH of all reacts to synthesize the organic-inorganic hybrid composite represented by the following Chemical Formula 3 as shown in Scheme 2 below.

For Formula ^{3, X, Y, R 1} , R 2 and n have the same meaning as ^{X, Y, R 1, R} 2 and n of the formula (1) described above.

[ Step 3]: Synthesis of Organic / Inorganic Hybrid Compound

As shown in Scheme 3 below, the additive for improving hydrolysis of the present invention represented by Chemical Formula 1 may be prepared by reacting the organic / inorganic hybrid complex represented by Chemical Formula 3 with the polyol represented by Chemical Formula 4 below. have.

In Chemical Formula 4,

R ³ is a linear or pulverized aliphatic alkylene group or alicyclic alkylene group having a number average molecular weight of 200 to 8,000, which is a saturated hydrocarbon or an unsaturated hydrocarbon, and may include an ester group, an ether group, a carbonate group, and the like in the main chain. .

[Low specific gravity beads]

The present invention is characterized by using low specific gravity beads to lower the specific gravity of the foam. In the present invention, single or two or more selected from aluminosilicate, borosilicate, silica and aerosil can be used within the range of not impairing the stability of the foam composition, lowering the specific gravity of the foam and maintaining physical properties. In order to achieve this, it is more preferable to use beads having a density of 0.05 to 0.2 g / cm 3 and a size of 10 to 110 μm. Specific examples of low specific gravity beads having such density and size include U.S. 3M K1 (borosilicate glass, density: 0.125g / cm3, size: 100㎛), S15 (borosilicate glass, density: 0.15g / cm3, size: 90 μm). In this case, when the density of the low specific gravity beads is less than 0.05 g / cm 3, workability may be poor, and a problem that may damage worker health may occur due to particles floating in the air, and when the concentration of the low specific gravity beads is greater than 0.2 g / cm 3, the specific gravity reduction effect may not be exhibited. There may be a problem, there may be a problem that the reinforcement effect is insufficient when the size of the low specific gravity beads is less than 10 ㎛, there may be a problem that the mechanical properties are degraded due to the bead particles larger than the cell size in the foam when more than 110 ㎛ As such, it is preferable to use low specific gravity beads having a density and size within the above range.

All organic / inorganic hybrid compounds and low specific gravity beads used in the present invention described below use those having the characteristics of the organic / inorganic hybrid compound and low specific gravity beads described above.

The low specific gravity polyurethane foam composition excellent in hydrolysis resistance of the present invention is a polyol mixture containing a polyol, a crosslinkable compound, a catalyst, a foam stabilizer, a foaming agent, a low specific gravity bead and an organic / inorganic hybrid compound having the formula (1); And isocyanate prepolymer; characterized in that it includes, and will be described in detail with respect to each of the compositions included in the present invention.

[Polyol]

In the present invention, it is preferable to use a polyol having a number average molecular weight of 1,000 to 4,000 and two or more hydroxy groups, the polyol is selected from polyether-based polyols, polyester-based polyols and phenolic polyols or 2 When the number average molecular weight of the polyol is less than 1,000, it is possible to use more than one species. Here, the hardness may be good, but other physical properties may be poor. When the foam is more than 4,000, the viscosity is high so that isocyanate prepolymer and other It is preferable to use a polyol having a number average molecular weight within the above range because it may cause a problem that the physical properties are not mixed well with the additive.

The polyether polyol may be obtained by addition reaction of an alkylene oxide such as ethylene oxide and propylene oxide with a polyhydroxyalkane or an amine compound, and the hydroxyalkane may be glycols such as ethylene glycol and propylene glycol, glycerol, trimethyl It is preferable to use triols such as olpropane, and ammonia, triethanolamine, ethylenediamine and the like can be used as the amine compound. Specifically, single or two or more polyether polyols selected from polyethylene glycol, polypropylene glycol, and polytetramethylene glycol may be used.

The polyester-based polyol may be obtained by reaction of dicarboxylic acid containing 2 to 12 carbon atoms with at least one diol, and specifically selected from polycaprolactone diol, polycarbonate diol, polyethylene terephthalate diol, and polybutyrate Single or 2 or more types of polyester polyols can be used.

The dicarboxylic acid may be an aliphatic divalent acid such as adipic acid, succinic acid, azelaic acid, sebacic acid, suberic acid, glutaric acid, etc .; And aromatic acids such as phthalic acid, isophthalic acid, terephthalic acid, naphthenic acid and the like; Single or 2 or more types selected from among these can be used.

The diol is a glycol containing 2 to 8 carbon atoms, such as ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, or 1,6-hexanediol;

Polyhydric alcohols such as glycerol, trimethylolpropane, pendaerythritol and the like; And

Lactone polyester polyols obtained by ring-opening polymerization of cyclic esters such as caprolactone; One or two or more diols selected from among them can be used.

In addition, the phenolic polyol may be a monophenol or two or more selected from polyphenols prepared by reacting a noblock resin and an alkylene oxide, and polyphenols prepared by reacting a resol resin and an alkylene oxide.

In the present invention, as described above, the polyol may be one or two or more selected from polyether polyols, polyester polyols, and phenolic polyols according to the properties of the foam.

[Crosslinkable Compound]

The crosslinkable low molecular weight compound, which is a composition of the present invention, plays a role of controlling the stability and hardness of the foam, and may have an average molecular weight of 30 to 400, and contains active hydrogen capable of reacting with an isocyanate. It is preferable to use two or more functional groups.

The crosslinkable compound may include at least one amine compound selected from diethanolamine, glycerin, triethanolamine, diisopropanolamine and the like; And

Ethylene glycol, butanediol, tetraethylenepentamine, polyethyleneamine, trimethylolpropane, alkylene oxides having an average molecular weight of 50 to 400, polyfunctional amines, adducts of alcohols or various low molecular weight multifunctional hydroxy compounds; Single or 2 or more types selected from among them can be used.

[catalyst]

In the preparation of the foam, the catalyst, which is the composition of the present invention, controls the speed and timing of the two reactions so that the crosslinking reaction (gel reaction) and the foaming reaction proceed at an appropriate time to obtain a good foam structure. .

In the present invention, the catalyst is a tertiary amine such as triethylamine, N-methylmorpholine, N, N`-dimethylbenzylamine, N, N`-dimethylethanolamine;

Strong bases such as alkali and alkaline earth metal hydroxides, alkoxides and phenoxides;

Acidic metal salts such as ferric chloride, tin chloride, antimony trioxide, bismuth nitrate;

Metal chelates such as acetyl acetone, benzoyl acetone, trifluoroacetyl acetone and ethyl acetoacetate; And

Various metals such as sodium acetate, potassium laurate, calcium hexanoate, tin acetate, octosan tin, and tin oleate; Single or 2 or more types selected from among them can be used.

[Foam stabilizer]

In the present invention, the foam stabilizer serves to improve the physical properties of the foam by improving the mixing properties of the various components and to prevent agglomeration of the resulting bubbles to stabilize and uniformize the bubbles, generally used in the production of polyurethane foam Foam stabilizers may be used, and alkylsiloxanes and polyether block copolymers or alkylsiloxanes and polyester block copolymers may be used, and more preferably, block copolymers of dimethylsiloxane and polyether, dimethylsiloxane and polyester It is preferable to use single or 2 or more types selected from block copolymers.

[blowing agent]

In the present invention, the blowing agent serves to react with the isocyanate to generate the small dioxide,

Water (H ₂ O); Low boiling hydrocarbons such as pentane, hexane, heptane and pentene; Azo compounds, such as azohexahydro benzonitrile; And

Halogenated hydrocarbons such as dichlorodifluoroethane, vinylidene chloride and methylene chloride; Single or 2 or more types selected from among them can be used.

[Isocyanate Prepolymer]

The isocyanate prepolymer, which is another composition of the present invention, may be a prepolymer having an isocyanate group at its terminal, and a molar ratio of hydroxy group and isocyanate group of 1: 1.2 to 1.5. Here, when the molar ratio of the hydroxy group and the isocyanate group is less than 1: 1.2, the viscosity of the product may be high, which may cause a problem in manufacturing the foam, and when the ratio is greater than 1: 1.5, other physical properties other than the hardness of the prepared foam may occur. It is preferable to use an isocyanate prepolymer having a molar ratio within the above range.

As the isocyanate prepolymer, an aromatic compound, a saturated cyclic compound, an unsaturated cyclic compound, or an aliphatic compound may be used, and more preferably, toluene diisocyanate, xylene diisocyanate, hydrogenated methylene diphenyl diisocyanate, hydrogenated toluene diisocyanate, and the like. It is possible to use a mixture of one or more selected from isophorone diisocyanate and hexamethylene diisocyanate.

The polyol mixture containing the low specific gravity beads of the present invention and the organic / inorganic hybrid compound having Formula 1 is as described above.

Hereinafter will be described in detail with respect to the present invention mainly on the composition ratio of the composition of the present invention described above.

Low specific gravity polyurethane foam composition of the present invention is excellent

3 to 20 parts by weight of the crosslinkable compound, 0.1 to 1.5 parts by weight of the catalyst, 0.1 to 3 parts by weight of the foam stabilizer, 0.5 to 3 parts by weight of the blowing agent, 3 to 15 parts by weight of the low specific gravity beads and the formula 1 Polyol mixture containing 2 to 15 parts by weight of an organic-inorganic hybrid compound having a; And isocyanate prepolymers.

Herein, when the crosslinkable compound is less than 3 parts by weight with respect to 100 parts by weight of the polyol, the hardness of the polyurethane foam is lowered, and when it exceeds 20 parts by weight, the hardness is too high, which may cause a problem of lowering other mechanical properties. Good to use at

When the catalyst is less than 0.1 part by weight with respect to 100 parts by weight of the polyol, the foam may not be sufficiently foamed. When the catalyst is more than 1.5 parts by weight, the foaming speed may proceed too fast, resulting in poor foam condition and cracking.

When the foam stabilizer is less than 0.1 part by weight with respect to 100 parts by weight of the polyol, the foam stabilization effect is not well obtained, and the expected physical properties are not obtained, and when the amount exceeds 3 parts by weight, the foam stabilization effect is not increased by increasing the amount, and the hardness is also increased. And physical properties such as tensile strength may be lowered.

When the blowing agent is less than 0.5 parts by weight based on 100 parts by weight of polyol may cause a problem that the desired foaming ratio can not be obtained due to the small amount of carbon dioxide, and when the blowing agent exceeds 3 parts by weight, the mechanical properties may be rather reduced, so it is used within the above range It is good.

The low specific weight beads (Beads) has a problem that the specific gravity of the foam is increased when used in less than 3 parts by weight with respect to 100 parts by weight of polyol, may cause a problem that the overall mechanical properties such as tensile strength, elongation rate is lowered when more than 15 parts by weight Therefore, it is preferable to use it within the said range.

The organic-inorganic hybrid compound is less than the hydrolysis resistance of the foam when used in less than 2 parts by weight with respect to 100 parts by weight of polyol, and more than 15 parts by weight of excellent hydrolysis resistance, but may cause other mechanical properties deterioration, It is good to add in the said range.

The isocyanate prepolymer

It is preferable to use the polyol and isocyanate prepolymer in a ratio of 100: 95 to 105, wherein when the isocyanate prepolymer is less than 95, the hardness of the foam is lowered. The problem of deterioration may occur, and it is preferable to use it within the above range.

Hereinafter will be described a method for producing a low specific gravity polyurethane foam composition excellent in hydrolysis resistance of the present invention described above.

Method for producing a polyurethane foam composition of the present invention

Preparing a polyol mixture by stirring and mixing a polyol, a crosslinkable compound, a catalyst, a foam stabilizer, a blowing agent, a low specific gravity bead, and an organic / inorganic hybrid compound having the formula (1); And

And mixing and stirring the polyol mixture and the isocyanate prepolymer.

The type and composition range of each of the polyurethane foam composition materials used in the production method are as described above, and when described in more detail,

Method for producing a polyurethane foam composition of the present invention

3 to 20 parts by weight of the crosslinkable compound, 0.1 to 1.5 parts by weight of the catalyst, 0.1 to 3 parts by weight of the foam stabilizer, 0.5 to 3 parts by weight of the blowing agent, 3 to 15 parts by weight of the low specific gravity beads and the formula 1 Preparing a polyol mixture by stirring and mixing 2 to 15 parts by weight of an organic / inorganic hybrid compound having a; And

And mixing, stirring and reacting the polyol and isocyanate prepolymer in a weight ratio of 100: 95 to 105.

Polyurethane foams prepared by the low specific gravity polyurethane foam composition and the manufacturing method excellent in the hydrolysis resistance of the present invention described above have an average density of 0.18 ~ 0.25 g / cm 3, generally having an average density of 0.25 ~ 0.34 g / cm 3 It is not only lighter because it has a lower density than conventional polyurethane foams, and because it has excellent hydrolysis resistance, it can be used as a bedding material, shock absorber, building material, and so on. When used as a polyurethane foam for the use can be used to maximize the effect.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the scope of the present invention is not limited by the following examples.

Preparation of Organic and Inorganic Hybrid Compounds

Preparation Example 1

90 g of tetramethoxytitanium and 10 g of bis (trimethoxypropyl) amine were mixed in a 1 L flask, and 5 g of 0.05N triethylamine was added thereto to react at room temperature for 24 hours to include an amino group at the end thereof, and to bind Ti-O-Ti. A metal oxide having a network structure of was prepared.

7.3 g of methylene diphenyl diisocyanate was mixed with 105 g of the metal oxide, 0.1 g of dibutyl tin dilaurate was added as a reaction catalyst, and the mixture was stirred for 2 hours in an oil bath at 80 ° C. under a nitrogen atmosphere. Hybrid composites were prepared.

112.3 g of the isocyanate-terminated organic-inorganic hybrid composite and 58.4 g of a polyester polyol having a number average molecular weight of 2,000 (K-320, KK) were added and reacted at 80 ° C. under a nitrogen atmosphere for 2 hours to represent the following Chemical Formula 5 An organic-inorganic hybrid compound was prepared.

) 결합의 망상 구조를 갖는 금속 산화물이며, n은 망상구조를 갖는 금속 산화물에 치환되는 유기화합물의 수를 나타낸다.In Chemical Formula 6, X is (

) Is a metal oxide having a network structure of the bond, and n represents the number of organic compounds substituted with the metal oxide having a network structure.

Preparation Example 2

80 g of tetramethoxysilane and 20 g of bis (trimethoxysilylpropyl) amine were mixed in a 1 L two-necked flask and 5 g of 0.1N triethanolamine was added, followed by reaction at room temperature at a speed of 100 to 200 rpm for 24 hours. A metal oxide containing an amino group at the terminal and having a network structure of Si—O—Si bonds was prepared.

14.6 g of methylene diphenyl diisocyanate was mixed with 105 g of the metal oxide, and then 0.1 g of dibutyltin dilaurate was added as a reaction catalyst, and the mixture was stirred for 2 hours in an oil bath at 80 ° C. under a nitrogen atmosphere to prepare an inorganic hybrid complex of the isocyanate terminal. Prepared.

120 g of a polyester polyol having a number average molecular weight of 2,000 (K-320, Dong Chem) and 0.1 g of dibutyl tin dilaurate were added to 119.6 g of the organic-inorganic hybrid composite, followed by reaction at 80 ° C. under a nitrogen atmosphere for 2 hours. To prepare an inorganic hybrid compound having a hydroxyl terminal having an amino group and a urethane group represented by the following formula (6).

) 결합의 망상 구조를 갖는 금속 산화물이며, n은 망상구조를 갖는 금속 산화물에 치환되는 유기 화합물의 수를 나타낸다.In Chemical Formula 5, X is (

) Is a metal oxide having a network structure of the bond, and n represents the number of organic compounds substituted with the metal oxide having a network structure.

Preparation of Polyurethane Foam

Example 1

100 parts by weight of polyester polyol (DT-2014 of Daewon Polymer, average molecular weight: 2,000), 10 parts by weight of ethylene glycol, 0.5 part by weight of triethylamine as an amine catalyst, 0.1 part by weight of dibutyltin dilaurate, foam stabilizer 0.5 parts by weight of a block copolymer of dimethylsiloxane and polyether (L-5420 of Witco, USA), 0.8 parts by weight of water as blowing agent, borosilicate glass (low density: 0.15 g / cm 3, size: 90) Μm, US 15M S15) 10 parts by weight, 5 parts by weight of the inorganic hybrid compound prepared in Preparation Example 1 was added and stirred and mixed at a speed of 2,000 rpm for 1 minute to prepare a polyol mixture.

Thereafter, 95 parts by weight of an isocyanate prepolymer (MP-5460, NCO content: 20%) of Dongsung Chemical Co., Ltd. was added to 100 parts by weight of the polyol, stirred at a speed of 2,000 rpm for 5 seconds, and poured into a mold, followed by hot air at 60 ° C. After standing in a circulation oven for 10 minutes to undergo foaming and crosslinking, a polyurethane foam having a specific gravity of 0.22 (block specific gravity) was prepared.

Examples 2-5

In the same manner as in Example 1 was carried out to have the composition shown in Table 1, Example 2 was used as polypolyproprolactonediol (DT-0241, Union molecular weight: 2,000, US Union carbide Co., Ltd.) of the polyester polyol, Example 3 changed the amount of isocyanate prepolymer added. In addition, Example 4 used borosilicate glass (K1 of 3M, USA) with a density of 0.125 g / cm 3 and 100 μm as low specific gravity beads, and Example 5 changed the amount of the inorganic hybrid compound used so that the polyurethane foam Was prepared.

Example 6

In the same manner as in Example 1 was carried out to have a composition as shown in Table 1, in contrast to Example 1 5 parts by weight of the inorganic hybrid compound prepared in Preparation Example 2 instead of the inorganic hybrid compound prepared in Preparation Example 1 It was carried out by.

Comparative Examples 1 to 4

To prepare a polyurethane foam in the same manner as in Example 1, it was carried out to have a composition of Table 1.

Experimental Example 1

Physical property test

Physical properties of the polyurethane foam prepared in Examples and Comparative Examples was carried out by the following method, the results are shown in Table 2 below.

[Hardness Measurement Experiment Method]

Hardness was measured in accordance with ASTM D 2240 with a Asker C type hardness tester for the smooth middle part of the foamed state by cutting the foam. The thickness of the specimen and the distance between the measurement points were 10 mm and 6 mm or more, respectively, and after five repeated measurements, the average value was the hardness of the sponge.

[Specific gravity measurement test method]

The specific gravity of the foam was measured using a model DMA-3, Ueshima's automatic specific gravity measurement device in the presence of the surface layer, and the average value was measured three times except for values exceeding 20% or more from the median value of the measured values. It was.

[Test method for measuring tensile strength & elongation]

After the obtained foam was made to a thickness of about 5 mm, a test piece was made with a B-type cutter according to KS M 6518 to measure tensile strength and elongation. At this time, five test pieces were used for the same test.

[Tear strength test method]

After the obtained foam was made to a thickness of about 5 mm, a test piece was made with a B-type cutter according to KS M 6518 to measure tensile strength and elongation. At this time, five test pieces were used in the same test, and the measurement conditions were performed according to KS M 6518.

[Experimental Compression Set (Cs) Measurement Experiment Method]

Permanent compression strain measurement was carried out in accordance with ASTM D-3754 for a specimen prepared in the form of a cylinder of 300.05 mm in diameter with a thickness of about 10 mm. Insert the test piece between two chrome plated parallel metal plates, insert a spacer corresponding to 50% of the test piece thickness, compress it, heat-treat it in an air circulation oven maintained at 50 ° C. for 6 hours, and then press the compression device. The test piece was taken out and cooled at room temperature for 30 minutes, and the thickness was measured. Three test pieces were used in the same test, and the permanent compression rate (Cs) is calculated by the following equation (1).

Cs (%) = [(t _o -t _f ) / (t _o -t _s )] × 100

In Equation 1, t _o is the initial thickness of the test piece, t _f is the thickness when cooled after the heat treatment, and t _s is the thickness of the spacer.

Experimental Example 2

Hydrolysis resistance test

The polyurethane foams prepared in Examples and Comparative Examples were left for 7 days at 70 ° C. and 95% relative humidity, and then dried for 24 hours to measure tensile strength to evaluate hydrolysis resistance at a rate of decreasing tensile strength. It is shown in Table 3 below, the value in parentheses ^* of Table 3 represents the measured tensile strength value.

Hereinafter, Experimental Examples 1 and 2 will be described.

Examining the results of the physical properties of Comparative Example 1 without adding an inorganic hybrid compound, it was found that the hydrolysis resistance was not very good, so that the tensile strength was very low with time, which means that the durability of the polyurethane foam was reduced. Means. In addition, Comparative Example 2, which does not add low specific gravity beads, has overall mechanical properties.

Is good, but the specific gravity is high.

In Comparative Example 3 prepared with low specific gravity beads of more than 15 parts by weight, specific gravity was low, but tensile strength and tear strength were not as good as those of Examples 1 to 6 of the present invention. In the case of Comparative Example 4 prepared in excess of the hydrolysis resistance was the best, it was confirmed that other physical properties are inferior.

Combining the Experimental Example 1 and Experimental Example 2, it can be seen that the physical properties of the polyurethane foams of Examples 1 to 6 of the present invention is relatively excellent when compared with the physical properties of the polyurethane foams of Comparative Examples 1 to 3, and in particular, It can be confirmed that hydrolysis resistance is excellent.

Claims (6)

A low specific gravity polyurethane foam composition having excellent hydrolyzability, comprising low specific gravity beads having a density of 0.05 to 0.2 g / cm 3, and an inorganic hybrid compound represented by the following Chemical Formula 1; [Formula 1]

In Chemical Formula 1, X is a metal oxide forming a network structure; ego Y is an amino group, a sulfide group, an ester group or an ether group including an element including one or two or more lone pairs selected from nitrogen (N), sulfur (S), and oxygen (O); And R ¹ and R ² is the same as or different from each other, a C ₁ to C ₁₈ straight or branched aliphatic alkylene group, alicyclic alkylene group, or aromatic group; And R ³ represents a linear or pulverized aliphatic alkylene group or alicyclic alkylene group having a number average molecular weight of 200 to 8,000; n represents the number of organic compounds substituted with a metal oxide having a network structure. The method of claim 1, 100 parts by weight of polyol, 3 to 20 parts by weight of crosslinking compound, 0.1 to 1.5 parts by weight of catalyst, 0.1 to 3 parts by weight of foam stabilizer, 0.5 to 3 parts by weight of foaming agent, 3 to 15 parts by weight of low specific gravity beads and Formula 1 Polyol mixtures containing 2 to 15 parts by weight of an inorganic hybrid compound; And an isocyanate prepolymer; A low specific gravity polyurethane foam composition having excellent hydrolyzability, comprising the isocyanate prepolymer in a weight ratio of 100: 95 to 105 with respect to the polyol. The method of claim 2, The polyol is a monopoly or two or more mixed polyols selected from polyester polyols, polyether polyols, and phenolic polyols, and has a number average molecular weight of 1,000 to 4,000. The method of claim 2, The low specific gravity polyurethane foam composition having excellent hydrolytic properties, characterized in that having a diameter of 10 ~ 110㎛ size. As the foamed polyurethane foam composition of any one of claims 1 to 4, A low specific gravity polyurethane foam having excellent hydrolysis ability, having a density of 0.18 to 0.25 g / cm 3. The method of claim 5, wherein Low specific gravity polyurethane foam, characterized in that it is used in shoes.