JP2003313350A - Extruded styrenic resin foam and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an extruded flame-retardant lightweight styrenic resin foam having excellent heat insulation properties and strengths, such as strength of bond to concrete, suitable for use as a building material by using a blowing agent having a low load on the environment. <P>SOLUTION: The extrusion foam is one prepared by extrusion-foaming a styrenic resin and prepared by using a blowing agent being a mixed blowing agent comprising water, an ether, and a 3-5C saturated hydrocarbon and containing (A) at least one cell diameter modifier selected from the group consisting of paraffin wax, liquid paraffin, a nonionic surfactant, and a fluorine- containing surfactant and (B) at least one water-dispersing agent selected from the group consisting of bentonite, a water-absorbing polymer compound, a porous inorganic substance, and silanol-group-containing anhydrous silica. A method for producing the foam is also provided. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate-shaped styrene resin extruded foam used for a heat insulating material for buildings and a method for producing the same. More specifically, it relates to a styrene resin extruded foam having excellent environmental compatibility, high heat insulation performance, and strength suitable for building materials such as adhesive strength with concrete, and flame retardancy, and a method for producing the same. .

[0002]

2. Description of the Related Art Conventionally, styrene resin extruded foams have been widely used as heat insulating materials for buildings because of their suitability for workability and heat insulating properties. To obtain these styrene resin extruded foams,
Styrene resin is heated and melted with an extruder, a foaming agent is added and kneaded in the middle, this fluidized gel is cooled to a temperature suitable for foaming, pressure is released to a low pressure area through a die, and foaming is simultaneously performed, and at the same time molded into a plate shape. However, a method of obtaining a foam is common. Here, as the foaming agent, CFCs and saturated hydrocarbons are used in order to obtain excellent heat insulating properties, and in order to obtain good mechanical properties, foam dimensional stability and productivity, styrene-based foaming agents are used. A technique of using a halogenated hydrocarbon represented by methyl chloride and ethyl chloride, which are easily permeable gases, in combination with a resin has been widely adopted and established in the art.

However, in recent years, ozone depletion, global warming,
Environmental issues such as the effects of chemical substances on the air and water quality have been highlighted, and it is desired to use a blowing agent that is environmentally friendly.

Recently, it has been suspected that volatile organic compounds released from building materials are involved as a cause of sick house syndrome associated with the increase in highly airtight and highly heat-insulated houses. There is a possibility that the foaming agent of the styrene resin extruded foam used as the heat insulating material may also be involved, and there is also an opinion that attention should be paid to fluorocarbons and halogenated hydrocarbons. Therefore, if a styrene-based resin extruded foam having an environment-friendly foaming agent and high heat insulation performance can be developed without using a freon or halogenated hydrocarbon foaming agent, it will meet the social demand.

Under these circumstances, the use of water as a part of the foaming agent has been studied.

[0006] WO 01/51551 discloses a technical content in which bentonite is added as a dispersion medium of water, water is effectively used as a foaming agent, and a foam having a large and small cell structure is more advantageously obtained. However, further improvement is necessary in order to stably obtain a lightweight foam having a foam density of 20 to 35 kg / m ³ without using a foaming agent of fluorocarbons and halogenated hydrocarbons. It was

Further, in Japanese Patent Publication No. 8-502786, a means for mixing a low molecular weight polymer, an oligomer, a hydrophilic polymer and the like in a method for producing a styrene resin extruded foam by using water as a part of a foaming agent. Discloses a method in which a styrene resin material has water solubility. However, a synthetic resin extruded foam that meets the heat insulation performance, mechanical strength, adhesive strength with concrete, etc. required for building materials has not been proposed yet.

As described above, while making effective use of water as a foaming agent, the use of a foaming agent compatible with the environment makes it possible to further improve a lightweight styrene resin extruded foam excellent in heat insulation performance, strength physical properties and flame retardancy. There is a long-awaited improvement.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and provides a foaming agent for CFCs and halogenated hydrocarbons, which has environmental effects such as ozone depletion and global warming. Not used, in particular, a lightweight styrene resin extruded foam that has a large and small cell structure and has excellent heat insulation performance, strength such as adhesion strength with concrete required for building materials applications, and flame retardancy. The purpose is to provide.

[0010]

In order to solve the above-mentioned problems, the inventors of the present invention have conducted extensive studies and as a result, as a foaming agent, use a mixed foaming agent of water, ether and saturated hydrocarbon, and foam water. In order to achieve high foaming by using it as a foaming agent, it contains a water dispersant having a water absorbing function, and at the same time, contains a cell size adjusting agent that has the function of expanding the foam cell diameter It was found that a foam having the following formula, in particular, a foam having a large and small cell structure can be obtained. Regarding mixed foaming agents, achieving high foaming, heat insulation, strength,
The technology was completed by specifying the mixing ratio and the total amount of use in consideration of the flame retardant and dimensionally stable foam quality, and also considering the risk of ignition during transportation of the foam.

That is, the present invention provides the following styrene resin extruded foam and a method for producing the same. (1) A styrene-based resin extruded foam obtained by extrusion-foaming a styrene-based resin, wherein a mixed foaming agent comprising water, ether, and a saturated hydrocarbon having 3 to 5 carbon atoms is used as a foaming agent, and paraffin is used. At least one kind of bubble size adjusting agent (A) selected from the group consisting of wax, liquid paraffin, nonionic surfactant, and fluorine-containing surfactant, and bentonite, water-absorbing polymer compound, porous inorganic substance, silanol group A styrene resin extruded foam containing at least one water dispersant (B) selected from the group consisting of anhydrous silica having (2) The styrene resin extruded foam according to the above (1), which has a foam density of 20 to 35 kg / m ³ and a foam thickness of 20 to 120 mm.

(3) 5 to 10 parts by weight of the blowing agent is used per 100 parts by weight of the styrenic resin. 5 to 30% by weight of water and 15 to 50% of ether are used based on 100% by weight of the blowing agent. %, And 20 to 80% by weight of at least one saturated hydrocarbon having 3 to 5 carbon atoms are mixed, and the styrene resin extruded foam according to (1) or (2) above. (4) 0.1 to 10 parts by weight of the bubble size adjusting agent (A) and 0.1 to 10 parts by weight of the water dispersant (B) per 100 parts by weight of the styrene resin.
1 to 10 parts by weight is contained, (1) to
A styrene resin extruded foam according to any one of (3).

(5) The styrene resin extruded foam according to any one of (1) to (4) above, wherein the water dispersant (B) is natural bentonite or purified bentonite. (6) Saturated hydrocarbons having 3 to 5 carbon atoms are propane and n-
The styrene resin extruded foam according to any one of (1) to (5) above, which is at least one saturated hydrocarbon selected from butane and i-butane.

(7) The bubbles forming the foam are mainly bubbles having a diameter of 0.25 mm or less and a diameter of 0.3 to 1 mm.
The cells are dispersed in a sea-island shape through a cell membrane, and the bubbles having a diameter of 0.25 mm or less have an occupied area ratio of 10 to 90% per foam cross-sectional area. The styrene resin extruded foam according to any one of (1) to (6).

(8) A method for producing a styrene resin extruded foam in which a styrene resin is heated and melted, a foaming agent is added to the styrene resin, and extrusion foamed through a die. On the other hand, 0.1 to 10 parts by weight of a cell size adjusting agent (A) selected from the group consisting of paraffin wax, liquid paraffin, nonionic surfactants, and fluorine-containing surfactants, bentonite, and high water absorption. 0.1 to 10 parts by weight of at least one water dispersant (B) selected from the group consisting of a molecular compound, a porous inorganic material, and silanic group-containing anhydrous silica, and 5 to 10 parts by weight as a foaming agent. Used, 5 to 30% by weight of water, 15 to 50% by weight of ether, and 20 to 80% by weight of at least one saturated hydrocarbon having 3 to 5 carbon atoms, based on the total amount of the blowing agent. Method for producing a styrene resin extruded foam coexist mixing a foaming agent consisting%, characterized in that the extrusion foaming.

[0016]

DETAILED DESCRIPTION OF THE INVENTION The inventors of the present invention have disclosed WO01 / 515.
As disclosed in No. 51, the technology of effectively using water as a foaming agent, and further, by creating a foam having a characteristic cell structure in which large and small bubbles are mixed, a more advanced foam insulation We have been continuously studying technologies to obtain performance.

Although water is a clean substance, it has almost no compatibility with styrene resins, so the amount added is limited. If the amount added is too large, it will not be uniformly dispersed in the resin and will be stable. There are problems that extrusion foaming is impossible and voids are generated in the foam. Therefore, it has been found that water is effectively dispersed as a foaming agent by adding an effective water-absorbing substance found in the example of bentonite to uniformly disperse water in a resin in an extruder. As a result, we have succeeded in developing a foam that has excellent heat insulation performance while using water as a foaming agent to some extent and using an environment-friendly foaming agent.

However, in order to produce a foam more economically and to obtain a foam having better handleability, it is necessary to step up the technique in order to obtain a further lightweight foam. Met.

Then, as a result of intensive studies, the above-mentioned problems were overcome and the technique was completed by the technique described below.

Also, it should be noted that regarding the adhesive strength of the heat insulating material with concrete required at the construction site,
We have found an effective point in the physical properties of foams that can improve the adhesive strength of the foams having large and small cell structures that have been obtained in the past.

At the construction site, a method of adhering a styrene resin extruded foam to concrete is widely used. However, the adhesiveness between the conventional styrene resin extruded foam having large and small cell structures and concrete is not always sufficient. By increasing the technical means of the present invention, it is possible to increase the average cell diameter of the foam having a large and small cell structure, making it easier for concrete to enter the cells and increasing the anchor effect, and It is presumed that the improvement of the adhesive strength of was achieved.

First, as a technique of the present invention, when a mixed foaming agent containing water is used for a styrene resin, a bubble diameter adjusting agent (A) having a function of expanding bubbles and a water styrene resin By including an additive of the water dispersant (B) having a function of improving dissolution, dispersion and absorption,
We have succeeded in improving the characteristics of the base resin and have found that the foaming ability of water can be fully utilized. If these (A) or (B) are used alone, their effects are not sufficiently exhibited, and a sufficient effect is obtained only by a synergistic effect.

Examples of the compound used as the cell size adjusting agent (A) include paraffin wax, liquid paraffin, nonionic surfactants and fluorine-containing surfactants. These compounds may be used alone or in combination of two or more. Can be used.

Examples of the nonionic surfactant include glycerin fatty acid ester, sucrose fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, lecithin and the like.

Examples of the fluorine-containing surfactant include fluoroalkyl (C ₂ -C ₁₀ ) carboxylic acid and N-perfluorooctanesulfonylglutamic acid dinalium.

Among these bubble diameter adjusting agents (A), paraffin wax and nonionic surfactants are most preferable.

Various compounds such as a viscosity modifier and a plasticizer were examined, and the above compounds were most effective in expanding the cell diameter when water was used as the foaming agent.

The content of the cell size adjusting agent (A) is appropriately adjusted according to the addition amount and ratio of the foaming agent, or the type and content of other additives, if used together. The amount is preferably 0.1 to 10 parts by weight, more preferably 0.15 to 5 parts by weight, and still more preferably 0.2 to 3 parts by weight with respect to 100 parts by weight of the resin.

If the content of the cell size adjusting agent (A) is less than the above range, the effect of reducing the weight of the foam tends not to be exhibited, and if it exceeds the above range, when the foam is to be molded into a plate shape, The foam tends to tear and become difficult to mold.

Examples of the compound used as the water dispersant (B) include bentonite, water-absorbing polymer compounds, porous inorganic substances, and silanic group-containing anhydrous silica. These compounds may be used alone or in combination of two or more. Can be used.

Examples of bentonite include natural bentonite, refined bentonite, organized bentonite and the like. The bentonite referred to in the present invention is a basic clay mineral whose main component is montmorillonite and which contains accompanying minerals such as quartz, α-cristobalite, opal, feldspar and mica. In terms of chemical components, bentonite has silicon oxide as its main component, and aluminum oxide has the next largest chemical component. In addition, montmorillonite is composed of a thin silicate layer of about 1 nm, the surface of the plate-like crystal particles is negatively charged, and the layers are electrically charged by interchanging cations such as sodium and calcium. It is said to be a clay mineral that keeps its neutrality and that when water comes into contact with it, water molecules hydrate in the exchangeable cations between the layers and the layers swell.

Examples of the water-absorbing polymer compound include polyacrylate resin, starch-acrylate graft copolymer resin, vinyl alcohol-acrylic acid copolymer resin, polyvinyl alcohol resin and the like.

Examples of the porous inorganic material include silica gel, activated carbon, zeolite, porous sodium silicate glass and the like.

Among these water dispersants (B), natural bentonite and purified bentonite are most preferable.

The content of the water dispersant (B) is appropriately adjusted according to the addition amount and ratio of the foaming agent, or the type and content of other additives when used in combination, the styrene resin 100 The amount is preferably 0.1 to 10 parts by weight, more preferably 0.15 to 5 parts by weight, and still more preferably 0.2 to 3 parts by weight with respect to parts by weight.

When the content of the water dispersant (B) is less than the above range, the ability to disperse and absorb water is deteriorated, water is spouted from the die, and voids are generated in the foam, resulting in a good foam. If the amount is more than the above range, a large amount of foreign matter will be present in the styrene resin, the foam film will be broken during foaming, and closed cells cannot be maintained, resulting in a good foam. Tends to be unmoldable.

The foam having a characteristic cell structure in which large and small cells coexist in the present invention means that small cells having a cell diameter of 0.25 mm or less have an occupied area ratio of 10 to 90% per foam cross-sectional area. To The occupied area ratio of the small bubbles is preferably 20 to 90% per foam cross-sectional area, and 30 to 90%.
% Is more preferable, and 40 to 90% is the most preferable. As described above, it is preferable that the small bubble occupying area ratio is large because the heat insulating performance is improved. In order to obtain a foam having a cell structure composed of large and small cells, water as a foaming agent can be used by successfully using the water dispersant (B) together with other foaming agents.

However, in the present invention, the cell structure of the foam may be either a uniform cell structure or a cell structure in which large and small cells are mixed. In order to improve the heat insulation performance of the foam, a cell structure in which large and small cells are mixed is preferable, and a uniform cell structure is preferable in terms of further reducing the weight of the foam.

In the technique of the present invention, water, ether, and saturated hydrocarbon having 3 to 5 carbon atoms are mixed as a foaming agent, and three kinds of foaming agents are mixed in an appropriate ratio, and the total amount of the foaming agent is It is to use an amount necessary to achieve high foaming with a foam density of 20 to 35 kg / m ³ .

The applicant of the present invention also examined the use of ether and saturated hydrocarbon having 3 to 5 carbon atoms as a foaming agent having good foaming performance without adversely affecting the environment when extruding and foaming a styrene resin. However, it can be said that the present invention is a further improvement thereof.

Ether has a large solubility in styrene resin and a high permeability, and is suitable for obtaining a high expansion ratio. However, since it is a flammable gas and has a characteristic that it is more easily released than foam, it may ignite when handling foam when it is used more than necessary, especially when it is transported. Can be considered.

Saturated hydrocarbons having 3 to 5 carbon atoms have relatively low permeability from the styrene resin and have a thermal conductivity of gas smaller than that of air, so that they remain in the foam and the heat insulating performance of the foam. Improve. However, since it is a flammable gas, when it is used for building materials, a flame retardant is usually added to the resin to impart flame retardancy to the foam, but the flame retardancy of this foam deteriorates. Have a tendency to

As described above, water has almost no compatibility with styrene resins. Further, since it has a high boiling point and is a liquid at room temperature, it tends to cause shrinkage of the foam immediately after foaming.

Therefore, although these substances are substances that do not have a bad influence on the environment, some ingenuity is required to use them as a foaming agent for styrene resins.

As a requirement of the foaming agent for stably extruding and foaming the styrene resin, the plasticizing action on the styrene resin is at least necessary. In addition, it is of course necessary to suppress the dimensional shrinkage immediately after foaming in terms of the quality of the foam, and to impart high thermal insulation performance, which is the most important quality required for the heat insulating material.
Mandatory. Therefore, in order to satisfy all of these, by finally mixing three kinds of foaming agents of water, ether, and saturated hydrocarbon having 3 to 5 carbon atoms in an appropriate ratio, finally the target foam is obtained. It was

Examples of the ether include dimethyl ether, diethyl ether, methyl ethyl ether, etc. These may be used alone or in combination of two or more kinds. Of these, dimethyl ether is most preferred as the saturated hydrocarbon having 3 to 5 carbon atoms, such as propane and n.
-Butane, i-butane, n-pentane, i-pentane,
Examples include neopentane. Among these, n-butane, i-butane and propane are preferable from the viewpoint of foamability and heat insulation performance of the foam.

In the mixed foaming agent, the mixing ratio of water is preferably 5% by weight or more and 30% by weight or less, more preferably 5% by weight or more and 25% by weight based on 100% by weight of the total amount of the blowing agent.
The amount of ether is not more than 15% by weight, and the mixing ratio of ether is preferably not less than 15% by weight and not more than 50% by weight, more preferably not less than 20% by weight and not more than 40% by weight, based on 100% by weight of the total amount of the blowing agent, and having 3 carbon atoms The mixing ratio of saturated hydrocarbon of 5 to 5 is 20% or more with respect to 100% by weight of the total amount of the blowing agent.
It is preferably 0% by weight or less, more preferably 30% by weight
The amount is 70% by weight or less.

When the mixing ratio of water is less than the above range, high foaming becomes difficult, and at the same time, the ether and the carbon number are 3 to.
Since the mixing ratio of the saturated hydrocarbon of No. 5 exceeds the above range, the problem described below tends to occur. If the mixing ratio of water exceeds the above range, the dispersion and absorption in the styrene resin will exceed the allowable range, and gas spouting from the die will occur, so that a good foam tends not to be obtained.

When the mixing ratio of ether is less than the above range, the foaming agent tends to be unable to be stably extruded because the foaming agent has little plasticizing effect on the styrene resin in the extrusion system. If the mixing ratio of ether exceeds the above range, the atmosphere concentration of ether may increase to a range where ignition may occur during transportation of the foamed material, such as in a truck carrier.

When the mixing ratio of the saturated hydrocarbon having 3 to 5 carbon atoms is less than the above range, the foam immediately after extrusion contracts and the dimensional stability of the foam tends to deteriorate. In addition, the obtained foam has poor heat insulation. When the mixing ratio of the saturated hydrocarbon having 3 to 5 carbon atoms exceeds the above range, the flame retardancy of the obtained foam tends to deteriorate.

The amount of the mixed foaming agent used varies depending on the set value of the expansion ratio, etc., but when a lightweight foam having a foam density of 20 to 35 kg / m ³ is obtained, the foaming agent is used. Is preferably 5 to 10 parts by weight, more preferably 6 to 100 parts by weight of the styrene resin.
~ 9 parts by weight. If the amount of the foaming agent added is less than 5 parts by weight, the expansion ratio is low, and it may be difficult to exhibit the properties of the resin foam such as light weight and heat insulation. On the other hand, if it exceeds 10 parts by weight, the amount of the foaming agent is excessive. It tends to cause defects such as voids in the foam.

In addition to the mixed foaming agent used in the present invention, the following foaming agents may be used in small amounts.
For example, ketones such as dimethyl ketone, methyl ethyl ketone, diethyl ketone, methyl n-propyl ketone, methyl n-butyl ketone, methyl i-butyl ketone, methyl n-amyl ketone, methyl n-hexyl ketone, ethyl n-propyl ketone, and ethyl n-butyl ketone. Alcohols such as methanol, ethanol, propyl alcohol, i-propyl alcohol, butyl alcohol, i-butyl alcohol and t-butyl alcohol, formic acid methyl ester, formic acid ethyl ester, formic acid propyl ester, formic acid butyl ester, formic acid amyl ester , Carboxylic acid esters such as propionic acid methyl ester and propionic acid ethyl ester, inorganic blowing agents such as nitrogen and carbon dioxide, and chemical blowing agents such as azo compounds can be used.

The pressure for adding or injecting the foaming agent is
The pressure is not particularly limited as long as it is higher than the internal pressure of the extruder or the like.

The styrenic resin used in the present invention is not particularly limited, and is a styrene homopolymer obtained only from a styrene monomer, a monomer copolymerizable with styrene monomer and styrene, or a derivative thereof. Random, block or graft copolymers, brominated polystyrene, modified polystyrene such as rubber-reinforced polystyrene, and the like. These may be used alone or in combination of two or more.

As the monomer copolymerizable with styrene,
Methyl styrene, dimethyl styrene, ethyl styrene,
Styrene derivatives such as diethylstyrene, isopropylstyrene, bromostyrene, dibromostyrene, tribromostyrene, chlorostyrene, dichlorostyrene, trichlorostyrene, etc., polyfunctional vinyl compounds such as divinylbenzene, acrylic acid, methacrylic acid, methyl acrylate, methacryl (Meth) acrylic compounds such as methyl acidate, ethyl acrylate, ethyl methacrylate and acrylonitrile, diene compounds such as budadiene or derivatives thereof, unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride, and the like. . These may be used alone or in combination of two or more.

Of the styrene resins, styrene homopolymer is preferable from the viewpoint of workability.

In the present invention, the flame retardant usually used in the thermoplastic resin can be used without special limitation, if necessary. For example, as a bromine-based flame retardant, hexabromocyclododecane, a bromide of an aliphatic or alicyclic hydrocarbon such as hexabromocyclooctane, hexabromobenzene, ethylenebispentabromodiphenyl, decabromodiphenylethane, decabromodiphenyl ether, Brominated aromatic compounds such as octabromodiphenyl ether and 2,3-dibromopropyl pentabromophenyl ether, tetrabromobisphenol A, tetrabromobisphenol A bis (2,3-dibromopropyl ether), tetrabromobisphenol A (2- Brominated bisphenol such as tetrabromobisphenol A diglycidyl ether, adduct of tetrabromobisphenol A diglycidyl ether and tribromophenol, etc. Lumpur and their derivatives, tetrabromobisphenol A
Polycarbonate oligomer, brominated bisphenol derivative oligomer such as epoxy oligomer of adduct of tetrabromobisphenol A diglycidyl ether and brominated bisphenol, ethylenebistetrabromophthalimide, bis (2,4,6-tribromophenoxy) ethane, etc. Brominated aromatic compounds, brominated acrylic resins, ethylenebisdibromonorbornanedicarboximide, and the like. As a chlorine-based flame retardant, chlorinated paraffin, chlorinated naphthalene, chlorinated aliphatic compounds such as perchloropentadecane, chlorinated aromatic compounds,
Examples thereof include chlorinated alicyclic compounds. These compounds may be used alone or in combination of two or more.

Among the flame retardants, bromine flame retardants are preferable from the viewpoint of flame retardancy, and hexabromocyclododecane and the like are particularly preferable from the viewpoint of compatibility with styrene resins.

In addition to the above flame retardant, WO01 / 308
96, a phosphorus compound having a nitrogen atom in the molecule, a tetrazole compound, cyanuric acid, isocyanuric acid, a derivative of cyanuric acid, a derivative of isocyanuric acid, a boric acid metal salt, boron oxide, a phosphoric acid ester system. Flame retardant aids such as compounds can also be used as appropriate.

In the present invention, silica, talc, calcium silicate, wollastonite, kaolin, clay, mica, zinc oxide, titanium oxide, calcium carbonate, etc. may be used, if necessary, within a range that does not impair the effects of the present invention. Inorganic compounds, sodium stearate, magnesium stearate, barium stearate, processing aids such as stearylamide compounds, phenolic antioxidants, phosphorus stabilizers, benzotriazoles, light resistance stabilizers such as hindered amines, Additives such as other flame retardants, antistatic agents, and coloring agents such as pigments may be contained.

The extruded styrene resin foam of the present invention is
I. B. The styrene resin is mixed with the bubble size adjusting agent (A), the water dispersant (B), and optionally other additives, and then heated and melted. After heating and melting the styrene resin,
A bubble size adjusting agent (A), a water dispersant (B), and optionally other additives are added and mixed. The styrene resin was mixed with the cell size regulator (A), the water dispersant (B), and other additives as required, and then the composition was heated and melted, and the composition was heated again by supplying it to the extruder. By various methods such as melting, the styrene resin, the bubble size adjusting agent (A), the water dispersant (B), and optionally other additives are supplied to a heating and melting kneading means such as an extruder, In a step, under high pressure conditions, a foaming agent is added to a styrenic resin to form a fluid gel, cooled to a temperature suitable for extrusion foaming, and the fluid gel is extruded and foamed in a low pressure region through a die to form a foam. It is manufactured by

The heating temperature, the melt-kneading time, and the melt-kneading means when heat-melting and kneading the styrene resin and the additive such as the foaming agent are not particularly limited. The heating temperature may be higher than or equal to the temperature at which the styrene resin used is melted, but the temperature at which molecular deterioration of the resin due to the influence of a flame retardant or the like is suppressed as much as possible, for example, 150 to 220 ° C.
A degree is preferable. The melt-kneading time cannot be unconditionally determined because it depends on the extrusion amount per unit time, the melt-kneading means, etc., but the time required for uniformly dispersing and mixing the styrene resin and the foaming agent is appropriately selected. The melt-kneading means may be, for example, a screw type extruder, but is not particularly limited as long as it is used for ordinary extrusion foaming. However, in order to suppress the molecular deterioration of the resin as much as possible, it is preferable to use a low shear type screw as the screw shape.

Further, the foam molding method is not particularly limited, but, for example, the foam obtained by releasing the pressure from the slit die may be cut by using a molding die and a molding roll installed in close contact with or in contact with the slit die. A general method for molding a plate-shaped foam having a large area can be used.

The thickness of the foam of the present invention is not particularly limited,
It is appropriately selected according to the application. For example, in the case of a heat insulating material used for applications such as building materials, in order to impart preferable heat insulating properties, bending strength and compressive strength, the thickness like a normal plate-like material is more preferable than the thin one like a sheet. Is preferred, usually 20 to 120 mm, preferably 20
~ 100 mm. The density of the foam of the present invention is preferably 20 to 35 kg / m ³ in order to impart lightweight and excellent heat insulating properties, bending strength and compressive strength, and 25 to ³⁰ kg / m ³ is preferable. It is more preferable that there is.

In some cases, the adhesiveness between the styrene resin extruded foam and the concrete may be said to be sufficient at about 20 N / cm ² , but according to the present invention, it is satisfied even in the situation where stronger adhesive strength is required. can be obtained ur foam, for example, 23N / cm ² or more, more 25 N / cm ² or more,
Most preferably more than 25 N / cm ² , 35 to 40
It is possible to obtain an adhesive strength of about N / cm ² .

[0066]

EXAMPLES Next, the extruded styrene resin foam of the present invention and the method for producing the same will be described in more detail based on examples, but the present invention is not limited to these examples.

The properties of the obtained foam are as follows: foam molding state, foam cross-sectional profile, foam cell diameter, foam density, foam thermal conductivity, foam compressive strength, foam flammability, and concrete. The adhesive strength was determined according to the following method.

(1) Molded state of foam The following evaluation was made. ◯: The foam has no cracks, cracks, dents, and voids, and a good foam is stably obtained. X: Gas is ejected from the die. The pressure fluctuation in the extrusion system is severe and a stable foam cannot be obtained. In foam,
There are cracks, cracks, pits, voids, etc., and only a poor foam can be obtained.

(2) Foam Section Profile The dimension of the obtained foam section in the thickness direction and the dimension in the width direction were measured. The dimension in the thickness direction was calculated as an average value of 3 points at both ends in the width direction and the center portion in the width direction.

(3) Foam Cell Bubble Diameter (mm) A cross section obtained by cutting the foam vertically (thickness direction) along the width direction was sampled, and this portion was scanned with a scanning electron microscope (manufactured by Hitachi Ltd., Part number: S-450) was used to magnify 30 times and photographed.
It measured according to TM D-3576. The actual size of the photographed part was about 5 mm × 5 mm. The sampling position may be anywhere in the foam, except for the special cell structure at the end of the foam. In this measurement, foam (thickness: 20 to 100 mm, width: 910 to 1)
(000 mm) at a position 100 mm inside from the end in the width direction, three or five points were sampled symmetrically vertically from the center of thickness. The foam cell diameter (mm) was the average of the values obtained at each sampling site.

(4) Foam density (kg / m ³ ) Foam density was determined based on the following formula and the unit is kg / m
Converted to ³ . Foam density (g / cm ³ ) = foam weight (g) / foam volume (cm ³ ).

In this measurement, the foam (thickness: 20 to 100
mm, width: 910 to 1000 mm) at both ends in the width direction and the center of the width direction, product thickness × width 300 mm × length 30
Measured by sampling with a sample size of 0 mm. The average value of 3 points was used.

(5) Thermal conductivity of foam (W / mK) Measured according to JIS A 9511 extruded polystyrene foam heat insulating plate. The measurement was carried out on the foam that had been produced for 30 days.

(6) Compressive Strength of Foam (N / cm ² ) It was measured according to JIS A 9511 extruded polystyrene foam heat insulating plate. The measurement was performed on the foam that had been produced for 7 days.

(7) Foam flammability It was measured according to JIS A 9511. The measurement was performed on the foam that had been produced for 7 days. If the criteria of "burn out within 3 seconds, do not burn without exceeding dust and burning limit indicator line" are satisfied, it is ○ (pass), and if this criterion is not reached, x (not Passed).

(8) Adhesive strength with concrete A foam is processed into a size of 30 mm in thickness, 910 mm in width and 1820 mm in length, and concrete is poured into the foam.
The concrete was cured and dried outdoors for 2 weeks to bond the foam and the concrete. After a disc jig having a diameter of 100 mm and a foam were adhered and cured with an epoxy adhesive, the disc jig was pulled out by a hydraulic press to measure the strength when the adhesive interface between the foam and concrete was peeled off. The adhesive strength was measured at arbitrary 6 points and the average value was taken as the adhesive strength.

Example 1 As the polystyrene resin, Styron G9401 manufactured by A & M Styrene Co., Ltd. was used,
Hexabromocyclododecane (hereinafter abbreviated as HBCD) as a halogen-based flame retardant, together with 100 parts by weight of polystyrene resin, 1 part by weight of paraffin wax as a cell size adjusting agent, 1 part by weight of bentonite as a water dispersant. 3 parts by weight, 0.1 part by weight of talc as a nucleating agent,
0.25 part by weight of barium stearate as a lubricant was dry blended, and these resin mixtures were fed to a tandem type extruder.

About 2 parts of the resin mixture fed to the first extruder was used.
The mixture is heated to 00 ° C. and melt-kneaded, and as a foaming agent, 2 parts by weight of water, 2.5 parts by weight of dimethyl ether, and 3 parts by weight of isobutane (based on 100% by weight of the foaming agent) are used per 100 parts by weight of the polystyrene resin. Then, a foaming agent consisting of 27% by weight of water, 33% by weight of dimethyl ether, and 40% by weight of isobutane) was pressed into the resin from different lines in the vicinity of the tip of the first extruder. After that, the resin temperature is adjusted to about 110 by a second extruder connected to the first extruder and further by a cooler.
It was cooled to 130 ° C. and extruded into the air from a die provided at the tip of a cooler, and an extruded foam plate having a cross-sectional shape with a thickness of 90 mm and a width of 1000 mm was obtained with a molding die and a molding roll.

The foam obtained had a foam cell diameter of 0.7.
It was a good foam having a size of 1 mm and a foam density of 23.4 kg / m ³ . The cell structure of the foam was a uniform cell structure. The thermal conductivity of the obtained foam is 0.038 W /
The mK and compressive strength were 24.3 N / cm ² , and the flammability satisfied JIS A 9511 standards. The adhesive strength with concrete was 34 N / cm ² .

Example 2 As the polystyrene resin, Styron G9401 manufactured by A & M Styrene Co., Ltd. was used,
With respect to 100 parts by weight of the polystyrene resin, 1.5 parts by weight of liquid paraffin as a cell size adjusting agent, 1 part by weight of bentonite as a water dispersant, 3 parts by weight of HBCD as a halogen-based flame retardant, and 0 of talc as a nucleating agent. 0.1 part by weight and 0.25 part by weight of barium stearate as a lubricant were dry blended, and these resin mixtures were supplied to a tandem type extruder.

The resin mixture fed to the first extruder was added to about 2
The mixture was heated to 00 ° C. and melt-kneaded, and as a foaming agent, 1.5 parts by weight of water, 2 parts by weight of dimethyl ether, and 3 parts by weight of isobutane (based on 100% by weight of the foaming agent) were used per 100 parts by weight of the polystyrene resin. Then, a foaming agent composed of 23% by weight of water, 31% by weight of dimethyl ether, and 46% by weight of isobutane) was press-fitted into the resin from different lines in the vicinity of the tip of the first extruder.

After that, the resin temperature is cooled to about 110 to 130 ° C. by a second extruder connected to the first extruder and further by a cooler, and the resin is extruded into the atmosphere from a die provided at the tip of the cooler and molded. Depending on the mold and forming roll, the thickness is 50 mm,
An extruded foam plate having a cross-sectional shape with a width of 1000 mm was obtained.

The obtained foam has a foam cell diameter of 0.5.
It was a good foam having a diameter of 2 mm and a foam density of 26.4 kg / m ³ . The cell structure of the foam was a uniform cell structure. The thermal conductivity of the obtained foam is 0.035 W /
The mK and compressive strength were 28.6 N / cm ² , and the flammability satisfied JIS A 9511 standards. The adhesive strength with concrete was 31 N / cm ² .

Example 3 As the polystyrene resin, Styron G9401 manufactured by A & M Styrene Co., Ltd. was used,
With respect to 100 parts by weight of the polystyrene resin, 1.5 parts by weight of lecithin which is a nonionic surfactant as a cell size adjusting agent, 1.5 parts by weight of bentonite as a water dispersant, and 3 parts by weight of HBCD as a halogen-based flame retardant. Parts, 0.1 part by weight of talc as a nucleating agent and 0.25 part by weight of barium stearate as a lubricant were dry blended, and these resin mixtures were supplied to a tandem type extruder.

About 2 parts of the resin mixture fed to the first extruder was used.
The mixture was heated to 00 ° C. and melt-kneaded, and as a foaming agent, 1 part by weight of water, 2 parts by weight of dimethyl ether, 2 parts by weight of isobutane, and 2 parts by weight of propane were used per 100 parts by weight of a polystyrene resin. 14% by weight of water, 29% by weight of dimethyl ether, and 57% by weight of saturated hydrocarbons of isobutane and propane are added to the resin near the tip of the first extruder from different lines. Pressed in. After that, the resin temperature is cooled to about 110 to 130 ° C. by a second extruder connected to the first extruder and further by a cooler, and the resin is extruded into the atmosphere from a die provided at the tip of the cooler, and a molding die and With the forming roll, the thickness is 80mm,
An extruded foam plate having a cross-sectional shape with a width of 1000 mm was obtained.

The obtained foam had a foam cell diameter of 0.5.
It was a good foam having a size of 6 mm and a foam density of 24.3 kg / m ³ . The cell structure of the foam was a uniform cell structure. The thermal conductivity of the obtained foam is 0.037 W /
The mK and compressive strength were 25.3 N / cm ² , and the flammability satisfied JIS A 9511 standards. The adhesive strength with concrete was 29 N / cm ² .

Example 4 As a polystyrene resin, Styron G9401 manufactured by A & M Styrene Co., Ltd. was used,
With respect to 100 parts by weight of the polystyrene resin, 1.5 parts by weight of a freon-based surfactant as a bubble size adjusting agent, 2 parts by weight of bentonite as an aqueous dispersant, and 3 parts by weight of HBCD as a halogen-based flame retardant, a nucleating agent. As talc 0.1
By weight, 0.25 part by weight of barium stearate as a lubricant was dry blended, and the resin mixture was supplied to a tandem type extruder.

About 2 parts of the resin mixture fed to the first extruder was used.
The mixture is heated to 00 ° C. and melt-kneaded, and as a foaming agent, 1.5 parts by weight of water, 2 parts by weight of dimethyl ether, and 3 parts by weight of propane (based on 100% by weight of the foaming agent) with respect to 100 parts by weight of the polystyrene resin. Then, a foaming agent consisting of 23% by weight of water, 31% by weight of dimethyl ether, and 46% by weight of propane) was pressed into the resin in the vicinity of the tip of the first extruder from different lines. Then, the resin temperature is adjusted to about 110 to 13 by the second extruder connected to the first extruder and further by the cooler.
It is cooled to 0 ° C., extruded into the atmosphere from a die provided at the tip of a cooler, and made to have a thickness of 40
An extruded foam plate having a cross-sectional shape of mm and a width of 1000 mm was obtained.

The obtained foam had a foam cell diameter of 0.4.
It was a good foam having a size of 1 mm and a foam density of 27.3 kg / m ³ . The foam structure of the foam was a mixture of large and small bubbles. The obtained foam had a thermal conductivity of 0.033 W / mK and a compressive strength of 29.3 N / cm ² ,
Regarding the flammability, the standard of JIS A 9511 was satisfied. The adhesive strength with concrete was 26 N / cm ² .

Example 5 As the polystyrene resin, Styron G9401 manufactured by A & M Styrene Co., Ltd. was used,
With respect to 100 parts by weight of the polystyrene resin, 1 part by weight of paraffin wax as a cell diameter adjusting agent, 1 part by weight of a water-absorbing polymer compound as a water dispersant, 3 parts by weight of HBCD as a halogen-based flame retardant, and a nucleating agent Talc 0.
1 part by weight and 0.25 part by weight of barium stearate as a lubricant were dry blended, and these resin mixtures were supplied to a tandem type extruder.

The resin mixture fed to the first extruder was adjusted to about 2
The mixture was heated to 00 ° C. and melt-kneaded, and as a foaming agent, 1.5 parts by weight of water, 2 parts by weight of dimethyl ether, and 3 parts by weight of isobutane (based on 100% by weight of the foaming agent) were used per 100 parts by weight of the polystyrene resin. Then, a foaming agent composed of 23% by weight of water, 31% by weight of dimethyl ether, and 46% by weight of isobutane) was press-fitted into the resin from different lines in the vicinity of the tip of the first extruder. After that, the resin temperature is adjusted to about 110 by a second extruder connected to the first extruder and further by a cooler.
It was cooled to 130 ° C. and extruded into the atmosphere from a die provided at the tip of a cooler, and an extruded foam plate having a cross-sectional shape with a thickness of 60 mm and a width of 1000 mm was obtained with a molding die and a molding roll.

The obtained foam has a foam cell diameter of 0.5.
It was a good foam having a size of 4 mm and a foam density of 28.1 kg / m ³ . The cell structure of the foam was a uniform cell structure. The thermal conductivity of the obtained foam is 0.034 W /
The mK and compressive strength were 30.7 N / cm ² , and the flammability satisfied JIS A 9511 standards. The adhesive strength with concrete was 29 N / cm ² .

Example 6 As a polystyrene resin, Styron G9401 manufactured by A & M Styrene Co., Ltd. was used,
With respect to 100 parts by weight of polystyrene resin, 1 part by weight of paraffin wax as a cell size adjusting agent, 1 part by weight of a porous inorganic material as a water dispersant, 3 parts by weight of HBCD as a halogen-based flame retardant, and 0% of talc as a nucleating agent. 0.1 part by weight and 0.25 part by weight of barium stearate as a lubricant were dry blended, and these resin mixtures were supplied to a tandem type extruder.

The resin mixture fed to the first extruder was adjusted to about 2
The mixture was heated to 00 ° C. and melt-kneaded, and as a foaming agent, 1.5 parts by weight of water, 2 parts by weight of dimethyl ether, and 3 parts by weight of isobutane (based on 100% by weight of the foaming agent) were used per 100 parts by weight of the polystyrene resin. Then, a foaming agent composed of 23% by weight of water, 31% by weight of dimethyl ether, and 46% by weight of isobutane) was press-fitted into the resin from different lines in the vicinity of the tip of the first extruder. After that, the resin temperature is adjusted to about 110 by a second extruder connected to the first extruder and further by a cooler.
It was cooled to 130 ° C. and extruded into the air from a die provided at the tip of a cooler, and an extruded foam plate having a cross-sectional shape with a thickness of 50 mm and a width of 1000 mm was obtained with a molding die and a molding roll.

The obtained foam had a foam cell diameter of 0.3.
It was a good foam having a diameter of 8 mm and a foam density of 29.1 kg / m ³ . The foam structure of the foam was a mixture of large and small bubbles. The thermal conductivity of the obtained foam was 0.
The compression strength was 032 W / mK, the compression strength was 31.5 N / cm ² , and the flammability satisfied the JIS A 9511 standard. The adhesive strength with concrete was 25 N / cm ² .

Example 7 As the polystyrene resin, Styron G9401 manufactured by A & M Styrene Co., Ltd. was used,
With respect to 100 parts by weight of the polystyrene resin, 1 part by weight of paraffin wax as a cell size adjusting agent, 1 part by weight of anhydrous silica having a silanol group as a water dispersant, together with 3 parts by weight of HBCD as a halogen-based flame retardant and a nucleating agent. As a lubricant, and 0.25 part by weight of barium stearate as a lubricant were dry-blended, and the resin mixture was supplied to a tandem type extruder.

About 2 parts of the resin mixture fed to the first extruder was used.
The mixture was heated to 00 ° C. and melt-kneaded, and as a foaming agent, 1.5 parts by weight of water, 2 parts by weight of dimethyl ether, and 3 parts by weight of isobutane (based on 100% by weight of the foaming agent) were used per 100 parts by weight of the polystyrene resin. Then, a foaming agent composed of 23% by weight of water, 31% by weight of dimethyl ether, and 46% by weight of isobutane) was press-fitted into the resin from different lines in the vicinity of the tip of the first extruder. After that, the resin temperature is adjusted to about 110 by a second extruder connected to the first extruder and further by a cooler.
It was cooled to 130 ° C. and extruded into the air from a die provided at the tip of a cooler, and an extruded foam plate having a cross-sectional shape with a thickness of 70 mm and a width of 1000 mm was obtained by a molding die and a molding roll.

The obtained foam had a foam cell diameter of 0.6.
It was a good foam having a diameter of 2 mm and a foam density of 25.4 kg / m ³ . The cell structure of the foam was a uniform cell structure. The thermal conductivity of the obtained foam is 0.035 W /
The mK and compressive strength were 24.1 N / cm ² , and the flammability satisfied JIS A 9511 standards. The adhesive strength with concrete was 25 N / cm ² .

Comparative Example 1 As a polystyrene resin, A & M Styrene Co., Ltd., trade name: Styron G9401 was used.
As a halogen-based flame retardant, H-type flame retardant was added to 100 parts by weight of polystyrene resin without adding a bubble size regulator and a water dispersant.
3 parts by weight of BCD, 0.1 part by weight of talc as a nucleating agent, and 0.25 part by weight of barium stearate as a lubricant were dry blended, and these resin mixtures were supplied to a tandem type extruder.

About 2 parts of the resin mixture fed to the first extruder was used.
The mixture was heated to 00 ° C. and melt-kneaded, and as a foaming agent, 1.5 parts by weight of water, 2 parts by weight of dimethyl ether, and 3 parts by weight of isobutane (based on 100% by weight of the foaming agent) were used per 100 parts by weight of the polystyrene resin. Then, a foaming agent composed of 23% by weight of water, 31% by weight of dimethyl ether, and 46% by weight of isobutane) was press-fitted into the resin from different lines in the vicinity of the tip of the first extruder. After that, the resin temperature is adjusted to about 110 by a second extruder connected to the first extruder and further by a cooler.
It was cooled to 130 ° C. and extruded into the atmosphere through a die provided at the tip of the cooler to obtain an extruded foam plate. However, a gas could not be ejected stably from the die, or the pressure fluctuation in the extrusion system was severe, and a stable foam could not be obtained. Although the foam was inferior, the physical properties of the foam were evaluated to the extent possible. The foam cross-section has a thickness of 30 mm and a width of 600 m.
m. The foam cell diameter is 0.31 mm and the foam density is 42.
6 kg / m ³ . Foam thermal conductivity is 0.038 W / mK,
Compressive strength is 45.6 N / cm ² , flammability is JI
It did not meet the criteria of SA 9511. The adhesive strength with concrete was 20 N / cm ² .

Comparative Example 2 As the polystyrene resin, Styron G9401 manufactured by A & M Styrene Co., Ltd. was used,
With respect to 100 parts by weight of the polystyrene resin, 1 part by weight of bentonite was added as a water dispersant without adding a bubble size adjusting agent, and 3 parts by weight of HBCD as a halogen-based flame retardant and 0.1 part by weight of talc as a nucleating agent. Parts, 0.25 part by weight of barium stearate as a lubricant is dry blended,
These resin mixtures were fed to a tandem extruder.

The resin mixture fed to the first extruder was mixed with about 2
The mixture was heated to 00 ° C. and melt-kneaded, and as a foaming agent, 1.5 parts by weight of water, 2 parts by weight of dimethyl ether, and 3 parts by weight of isobutane (based on 100% by weight of the foaming agent) were used per 100 parts by weight of the polystyrene resin. Then, a foaming agent composed of 23% by weight of water, 31% by weight of dimethyl ether, and 46% by weight of isobutane) was press-fitted into the resin from different lines in the vicinity of the tip of the first extruder. After that, the resin temperature is adjusted to about 110 by a second extruder connected to the first extruder and further by a cooler.
It was cooled to 130 ° C. and extruded into the atmosphere from a die provided at the tip of a cooler, and an extruded foam plate having a cross-sectional shape with a thickness of 60 mm and a width of 1000 mm was obtained with a molding die and a molding roll.

The obtained foam had a foam cell diameter of 0.1.
It was a good foam having a size of 9 mm and a foam density of 32.3 kg / m ³ . The foam structure of the foam was a mixture of large and small bubbles. The obtained foam had a thermal conductivity of 0.027 W / mK and a compressive strength of 26.4 N / cm ² ,
Regarding the flammability, the standard of JIS A 9511 was satisfied. The adhesive strength with concrete was 22 N / cm ² .

Comparative Example 3 As the polystyrene resin, A & M Styrene Co., Ltd., trade name: Stylon G9401 was used.
To 100 parts by weight of polystyrene resin, 1 part by weight of paraffin wax was added as a bubble size adjusting agent, and no water dispersant was added. In addition, HBC was used as a halogen-based flame retardant.
D3 parts by weight, talc 0.1 part by weight as a nucleating agent, and barium stearate 0.25 part by weight as a lubricant were dry blended, and these resin mixtures were supplied to a tandem type extruder.

The resin mixture fed to the first extruder was mixed with about 2
The mixture was heated to 00 ° C. and melt-kneaded. As a foaming agent, 1.5 parts by weight of water, 2 parts by weight of dimethyl ether, and 3 parts by weight of isobutane were added to 100 parts by weight of a polystyrene resin (based on 100% by weight of the foaming agent). , 23% by weight of water, 31% by weight of dimethyl ether, and 46% by weight of isobutane) were pressed into the resin from different lines in the vicinity of the tip of the first extruder. Then, the resin temperature is adjusted to about 110 to 13 by the second extruder connected to the first extruder and further by the cooler.
It was cooled to 0 ° C. and extruded into the atmosphere from a die provided at the tip of the cooler to obtain an extruded foam plate. However,
The pressure fluctuation in the extrusion system was severe and a stable foam could not be obtained. The foam was a poor foam with cracks, cracks, voids and the like. Although the foam was inferior, the physical properties of the foam were evaluated to the extent possible.

The cross-sectional shape of the foam is 40 mm thick and 70 mm wide.
0 mm. Foam bubble diameter 0.21mm, foam density 4
1.2 kg / m ³ . Foam thermal conductivity is 0.039 W / m
K, compressive strength was 39.1 N / cm ² , and flammability did not meet the JIS A 9511 criteria. The adhesive strength with concrete was 21 N / cm ² .

Table 1 collectively shows the results obtained in Examples 1 to 7 and Comparative Examples 1 to 3.

[0108]

[Table 1]

[0109]

According to the present invention, it is possible to obtain a lightweight styrene resin extruded foam having excellent environmental compatibility, high heat insulation properties, strength and flame retardancy suitable for building materials. Also, the adhesive strength with concrete is improved.

Continued front page    F-term (reference) 4F074 AA32 AC32 AD00 BA34 BA35                       BA36 BA37 BA38 BA39 BA75                       BA95 BC01 BC02 BC11 BC15                       CA22 DA02 DA03 DA23 DA32                 4F207 AA13 AB10 AB16 AB20 AG20                       KA01 KA11

Claims (8)

[Claims] 1. A styrenic resin extruded foam obtained by extruding and foaming a styrenic resin, wherein a mixed foaming agent comprising water, ether, and a saturated hydrocarbon having 3 to 5 carbon atoms is used as a foaming agent. , Paraffin wax, liquid paraffin,
From at least one type of bubble size adjusting agent (A) selected from the group consisting of nonionic surfactants and fluorine-containing surfactants, and bentonite, water-absorbing polymer compounds, porous inorganic substances, and silanic anhydride silica A styrene resin extruded foam containing at least one water dispersant (B) selected from the group consisting of: 2. The extruded styrene-based resin foam according to claim 1, wherein the foam density is 20 to 35 kg / m ³ and the foam thickness is 20 to 120 mm. 3. The blowing agent is used in an amount of 5 to 10 parts by weight based on 100 parts by weight of the styrene resin, and the total amount of the blowing agent is 10.
5% to 30% by weight of water and 1% of ether to 0% by weight
The styrene resin extruded foam according to claim 1 or 2, wherein 5 to 50% by weight and 20 to 80% by weight of at least one kind of saturated hydrocarbon having 3 to 5 carbon atoms are mixed. 4. With respect to 100 parts by weight of the styrene resin,
The styrene according to any one of claims 1 to 3, which contains 0.1 to 10 parts by weight of the cell diameter adjusting agent (A) and 0.1 to 10 parts by weight of the water dispersant (B). Resin extruded foam. 5. The water dispersant (B) is natural bentonite,
It is refined bentonite, It is characterized by the above-mentioned.
The styrene resin extruded foam according to any one of 1. 6. The saturated hydrocarbon having 3 to 5 carbon atoms is at least one saturated hydrocarbon selected from propane, n-butane and i-butane.
The styrene resin extruded foam according to any one of 5 above. 7. The foam-forming bubbles are mainly composed of bubbles having a bubble diameter of 0.25 mm or less and bubbles having a bubble diameter of 0.3 to 1 mm, and these bubbles are dispersed in a sea-island shape through a cell membrane. The styrene resin extruded foam according to any one of claims 1 to 6, wherein the cells having a cell diameter of 0.25 mm or less have an occupied area ratio of 10 to 90% per foam cross-sectional area. 8. A method for producing an extruded styrene resin foam, which comprises heating and melting a styrene resin, adding a foaming agent to the styrene resin, and extruding and foaming the resin through a die. 0.1 to 10 parts by weight of at least one type of cell diameter adjusting agent (A) selected from the group consisting of paraffin wax, liquid paraffin, nonionic surfactants, and fluorine-containing surfactants, bentonite, and water absorbency. 0.1 to 10 parts by weight of at least one water dispersant (B) selected from the group consisting of a polymer compound, a porous inorganic material, and anhydrous silica having a silanol group is contained,
Further, as the foaming agent, 5 to 10 parts by weight of the total amount of the foaming agent is used, and 5 to 3 parts of water is added to 100% by weight of the total amount of the foaming agent.
Styrene characterized by extruding and foaming in the presence of a mixed blowing agent of 0% by weight, 15 to 50% by weight of ether, and 20 to 80% by weight of a saturated hydrocarbon having 3 to 5 carbon atoms. Method for producing resin-based extruded foam.