JP2006198933A - Composite foam - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide composite foam having good thermal insulation properties over a long time by a simple method. <P>SOLUTION: The composite foam obtained by laminating/applying an epoxy-based curing resin which is cured in a short time at room temperature (within 24 h at 0-40°C) on the surface of a foamed styrene-based resin formed by extruding/foaming a styrene-based resin composition with a foaming agent of a 3-5C saturated hydrocarbon and its production method are provided. The composite foam, owing to its excellent thermal insulation properties, is used in various applications, especially in insulating material for construction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a composite foam having good heat insulating properties over a long period of time.

Styrene resin is heated and melted with an extruder, etc., and then a foaming agent such as aliphatic hydrocarbon, chlorinated hydrocarbon, fluorinated hydrocarbon, or chlorine fluorinated hydrocarbon is added and allowed to cool. A method of continuously producing a styrenic resin foam by extruding it into a low pressure region is already known (see, for example, Patent Document 1).

  Immediately after the production of the styrene resin foam thus obtained, the foam cells (cells) are filled with only the foaming agent having a low thermal conductivity as described above, so that it is good as a styrene resin foam. It has a good heat insulating property. However, since air permeates into the foam cell with the passage of time, the heat insulation tends to be gradually lowered. In addition, from a long-term perspective, the heat insulating property tends to decrease over time because the foaming agent is diffused from the cells.

  It is conceivable to add more foaming agent for the purpose of preventing a decrease in heat insulation due to the diffusion of the foaming agent from inside the cell, but the moldability of the resulting foam deteriorates and is combustible as a foaming agent. In the case of using a functional aliphatic hydrocarbon, there is a problem that the flame retardancy of the obtained foam is lowered.

  Therefore, a non-halogen material is used as a method to prevent the intrusion of air into the styrenic resin foam using a foaming agent that does not contain halogen, and to prevent the foaming agent from escaping from the foam, and to maintain thermal insulation over the long term. There is known a foam in which the above film is formed (see, for example, Patent Document 2). However, when laminating non-halogen-based films, it is necessary to stick with an adhesive or the like and workability is not good, and methods such as spraying and applying phenol resin are also mentioned, but in order to cure In some cases, post-treatment is troublesome, such as heating is required.

  In addition, in a foam containing fluorinated hydrocarbon as a foaming agent, a method for suppressing deterioration of heat insulation over time by pasting a gas barrier film with an epoxy resin adhesive is already known (for example, Patent Documents). 3)), however, in the case of styrene resin foam using a C3-C5 saturated hydrocarbon having excellent environmental compatibility as a foaming agent, simply attaching a gas barrier film with an epoxy resin adhesive Emission suppression is not sufficient and adjustment of the thickness of the epoxy resin adhesive is necessary.

  On the other hand, a method for producing a foam by heating and melting a polyamide resin having a gas barrier property higher than that of polystyrene and adding a foaming agent has also been proposed. However, molding is not easy, and the obtained foam is independent. It is difficult to say that the heat-insulating deterioration with time is sufficiently suppressed due to the low bubble rate (see, for example, Patent Documents 4 and 5).

As a resin foam having both mechanical strength and light weight, a polystyrene foam particle bonded with an epoxy resin-based cured product is known, but the epoxy resin-based cured product is used for bonding polystyrene foam particles. No mention is made regarding the heat insulating properties of the obtained foamed molded article (see, for example, Patent Document 6).
Japanese Patent Publication No.31-5393 JP 2002-144497 A JP 58-162337 A JP-A-5-209079 JP 2000-86800 A JP 2001-62860 A

  Under such circumstances, the problem to be solved by the present invention is to provide a composite foam having a good heat insulating property over a long period of time by a simple method.

  As a result of diligent research to solve the above-mentioned problems, the present inventors have found that a composite foam formed by laminating and coating an epoxy-based cured resin on the surface of a styrene-based resin foam obtained by extrusion foaming together with a specific foaming agent. The body was found to have good thermal insulation over a long period of time, leading to the present invention.

  That is, the present invention laminates an epoxy-based cured resin that cures at room temperature on the surface of a styrene-based resin foam obtained by extrusion foaming a styrene-based resin composition together with a foaming agent composed of a saturated hydrocarbon having 3 to 5 carbon atoms. The present invention relates to a composite foam formed by coating.

  It is preferable that the epoxy-based cured resin includes an epoxy-based compound as a main agent and a curing agent.

  It is preferable that the epoxy compound as the main agent is bisphenol A type diglycidyl ether and / or bisphenol A type epoxy resin.

  The curing agent preferably contains at least one compound selected from the group consisting of polyamide, polyamine, polyamidoamine, and polythiol.

  It is preferable that the average thickness of the laminated epoxy resin is 0.1 to 500 micrometers.

  It is preferable that a gas barrier material is further laminated and coated on the surface of the styrenic resin foam.

  It is preferable that the gas barrier substance contains at least one resin selected from the group consisting of a polyamide-based resin, a polyacrylonitrile-based resin, a polystyrene-based resin, a polyvinylidene chloride-based resin, and an ethylene-vinyl alcohol copolymer.

The partial pressure of air contained in the bubbles (cells) of the styrene resin foam is preferably 50 kilopascals or less.
In the present invention, the partial pressure of air contained in bubbles (cells) of a styrene resin foam obtained by extruding and foaming a styrene resin composition together with a foaming agent composed of a saturated hydrocarbon having 3 to 5 carbon atoms. The present invention relates to a method for producing a composite foam obtained by laminating and coating an epoxy-based cured resin on the surface of the styrene-based resin foam at a time of 50 kilopascals or less.

  Furthermore, the present invention relates to a method for producing a styrene resin foam obtained by extruding and foaming a styrene resin composition together with a foaming agent composed of a saturated hydrocarbon having 3 to 5 carbon atoms, which is extruded from an extruder into the atmosphere. The present invention also relates to a method for producing a composite foam obtained by laminating and coating an epoxy-based cured resin on the surface of the styrene resin foam within 12 hours.

  ADVANTAGE OF THE INVENTION According to this invention, the composite foam which has favorable heat insulation over a long term is provided. The composite foam of the present invention is useful for various uses, particularly for the use of heat insulating materials for buildings, from the viewpoint of its excellent heat insulating properties.

  The present invention is a composite foam obtained by laminating and coating an epoxy-based cured resin that cures at room temperature on the surface of a styrene-based resin foam obtained by extrusion foaming a styrene-based resin composition together with a foaming agent. In styrenic resin foams that do not undergo coating treatment, air penetrates into the foam over time, and the foaming agent added during extrusion is gradually released into the atmosphere. descend. In other words, the thermal conductivity increases with time (hereinafter also referred to as heat-insulating deterioration over time). However, when the epoxy curable resin is laminated on the surface of the styrene resin foam as in the present invention, both the intrusion of air and the release of the foaming agent are suppressed, and the deterioration of heat insulation over time is dramatically improved. Is done.

  Thus, the epoxy-based cured resin suppresses both the release of the foaming agent and the intrusion of air in the laminated coating portion, and even if the laminated coating portion is a partial surface, the foaming agent from that portion Since the release of air and the intrusion of air can be suppressed, it is possible to improve the deterioration of heat insulation over time. However, a wider laminated coating portion is preferred, and most preferably, the entire surface of the styrene resin foam is laminated and coated with an epoxy-based cured resin.

  For example, in a styrene resin foam having a rectangular parallelepiped shape such as 1820 cm × 910 cm × 25 cm, it is preferable that one of the widest surfaces of 1820 cm × 910 cm among the six surfaces is laminated and coated with an epoxy-based cured resin, and 1820 cm × 910 cm It is more preferred to laminate and coat two of the widest surfaces, and most preferred to laminate and coat all six sides.

  In the present invention, the epoxy-based cured resin that cures at room temperature refers to an epoxy-based cured resin that cures within 24 hours in a temperature range of 0 ° C to 40 ° C. From the viewpoint of workability and productivity, an epoxy-based cured resin that cures within 10 hours at 10 ° C. to 35 ° C. is preferable, and an epoxy-based cured resin that cures within 12 hours at 15 ° C. to 30 ° C. is more preferable. Epoxy cured resins that cure below 0 ° C tend to exceed 24 hours before being cured. On the other hand, if the temperature exceeds 40 ° C., the curing time is shortened, but a heating device is required.

  In the present invention, the time to cure is fast, and from the viewpoint of productivity of curing at room temperature, or from the viewpoint of significantly suppressing the release of 3-5 saturated hydrocarbons used as a foaming agent, curing at room temperature. As the epoxy-based cured resin to be used, it is more preferable to use a two-pack type epoxy-based cured resin composed of an epoxy-based compound as a main component and a curing agent.

The epoxy compound used as the main agent is not particularly limited as long as it is an epoxy compound that is cured by reacting with a curing agent. Specifically, bisphenol A type diglycidyl ether, biphenyl diglycidyl ether, bisphenol F type diglycidyl ether, bisphenol AD type diglycidyl ether, bisphenol S type diglycidyl ether, bisphenol A type epoxy resin, bisphenol F type epoxy resin, Bisphenol AD type epoxy resin, bisphenol S type epoxy resin, etc., hydrogenated or brominated epoxy resin, glycidyl ester type epoxy resin, novolac type epoxy resin, urethane modified epoxy resin having urethane bond, metaxylenediamine, Nitrogen-containing epoxy resins epoxidized with hydantoin, etc., rubber-modified epoxy resins containing polybutadiene or NBR, etc. Phenol A diglycidyl ether, bisphenol A type epoxy resin is more preferable.
In addition, among these epoxy compounds, in consideration of handling properties when laminating and coating, an epoxy resin that is liquid or semi-solid at room temperature is more preferable, and about 300 Pascal second (about 300000 centipoise) or less at room temperature. Viscosity is most preferred.
As the curing agent, a general curing agent for epoxy resin may be used, and examples thereof include polyamide, polyamine, polyamidoamine, polythiol, polyalcohol, acid anhydride, polyphenol, etc., but rapid curing time or Taking into account the flexibility after curing, polyamides, polyamines (eg, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, metaxylylenediamine, mensendiamine, etc. as aliphatic polyamines; metaphenylenes as aromatic polyamines; Diamine, diaminodiphenylmethane, diaminodiethyldiphenylmethane, diaminodiphenylsulfone, etc .; secondary or tertiary amines include benzyldimethylamine, triethylenediamine, triethanolamine Piperidine, polyamidoamine, etc.), polyamide amine, polythiol is more preferable. Among these curing agents, in consideration of handling properties when laminating and coating, curing agents that are liquid or semi-solid at room temperature are more preferable, and those having a viscosity of about 200 Pascal second (about 200000 centipoise) or less at room temperature are the most. preferable.
When mixing the main epoxy compound and the curing agent, if necessary, a curing accelerator such as a tertiary amine may be added.

  The average thickness when the epoxy-based cured resin is laminated and coated is not particularly limited, but is preferably 0.1 to 500 μm, more preferably 10 to 300 μm in terms of suppression of foaming agent release and air infiltration. . If it is less than 0.1 micrometer, the effect of suppressing the release of the foaming agent and the infiltration of air becomes low, and if it exceeds 500 micrometers, the weight of the composite foam becomes heavy and handling becomes difficult.

In the present invention, a composite foam in which a gas barrier material is further laminated and coated on at least one surface of the styrene resin foam is a more preferable form in order to suppress the deterioration of heat insulation over time. Examples of such gas barrier substances include polyamide resins, polyacrylonitrile resins, polystyrene resins, polyvinylidene chloride resins, polyvinyl chloride resins, polybilyl alcohol resins, ethylene-vinyl alcohol copolymers, styrene-acrylonitrile. A copolymer, metal foil, etc. (aluminum foil etc.) are mentioned. Among these, polyamide resins, polyacrylonitrile resins, polystyrene resins, polyvinylidene chloride resins, and ethylene-vinyl alcohol copolymers are the most preferable from the viewpoint of suppressing heat deterioration over time.
These gas barrier substances are more preferably laminated and coated on at least one surface of the styrenic resin foam with an average thickness of 0.1 to 500 micrometers from the viewpoints of heat-insulating aging degradation and productivity. .

  In particular, when a film-like gas barrier material having an average thickness of 0.1 to 500 micrometers is used, lamination coating is easy and preferable. In such a case, different gas barrier films are laminated in advance on one gas barrier film, It is a more preferable form to combine a plurality of gas barrier substances by applying different gas barrier substances to one gas barrier film.

There is no limitation on the portion of the epoxy-based cured resin or gas barrier substance that is laminated and coated on the styrene-based resin foam, or the order of lamination. For example, the following cases (1) to (5) can be exemplified. .
(1) A styrenic resin foam is laminated with an epoxy-based cured resin, and a gas barrier material is further laminated thereon.
(2) A gas barrier material is laminated and coated on the styrene resin foam, and an epoxy-based cured resin is further laminated and coated thereon.
(3) An epoxy-based cured resin is laminated and coated on a part of the styrene-based resin foam, and a gas barrier material is laminated and coated on the remaining other part.
(4) Styrenic resin foam is alternately laminated with an epoxy-based cured resin and a gas barrier material.
(5) A styrene resin foam is laminated with an epoxy-based cured resin, and a styrene resin foam is laminated thereon. Further, if necessary, an epoxy-based cured resin, a gas barrier material, and a styrene resin foam are laminated and coated in an appropriate order.

Although there is no restriction | limiting in particular as air quantity contained in the bubble (cell) of the styrene resin foam in the composite foam of this invention, From a heat insulation viewpoint, it is 70 kg as a partial pressure of the air in a bubble (cell). It is preferably less than Pascal. More preferably, it is 50 kilopascals or less, and most preferably 25 kilopascals or less.
In the present invention, the partial pressure of air contained in bubbles (cells) of a styrene-based resin foam obtained by extruding and foaming a styrene-based resin composition together with a blowing agent composed of a saturated hydrocarbon having 3 to 5 carbon atoms is 50 This is a method for producing a composite foam obtained by laminating and coating an epoxy-based cured resin on at least one surface of the styrene-based resin foam at the time of kilopascal or less.
From the viewpoint of heat insulation, at the time when the partial pressure of air contained in the bubbles (cells) of the styrenic resin foam is 25 kilopascals or less, at least one surface of the styrenic resin foam is epoxy-based. More preferably, the cured resin is laminated and coated.

  There is no particular restriction on the point at which the epoxy-based cured resin or gas barrier material is laminated and coated on the styrene-based resin foam, but at the same time as the styrene-based resin foam is obtained by extrusion foaming, the release of the blowing agent is suppressed as much as possible. In addition, it is preferable from the viewpoint of heat insulation to suppress the intrusion of air due to the styrene resin foam being in contact with the atmosphere. However, even when the styrenic resin foam is obtained and the laminate coating is not performed at the same time, the release of the foaming agent and the intrusion of air after the laminate coating can be suppressed. It is possible to suppress deterioration.

  Therefore, in the method for producing a styrene resin foam obtained by extruding and foaming the styrene resin composition of the present invention together with a foaming agent composed of a saturated hydrocarbon having 3 to 5 carbon atoms, from the extruder to the atmosphere. A production method of a composite foam obtained by laminating and coating an epoxy cured resin on at least one surface of the styrene resin foam within 12 hours after extrusion is a preferred production method.

  From the viewpoint of heat insulation, it is more preferably within 6 hours, most preferably within 1 hour after being extruded from the extruder into the atmosphere.

  In the present invention, the method of laminating and coating the epoxy-based cured resin on the styrene-based resin foam is not particularly limited. (1) After mixing the main component epoxy resin and the curing agent, the styrene-based resin within the pot life. Method of applying to foam, (2) After mixing epoxy resin as main agent and curing agent, spraying to styrene resin foam within pot life, (3) Epoxy resin and curing as main agent After mixing the agent, a method of immersing the styrene resin foam within the pot life, (4) a method of laminating and coating a styrene resin foam with a pre-cured epoxy-based cured resin with an adhesive, etc. It is done.

  In the present invention, the method for laminating and coating the gas barrier substance on the styrene resin foam is not particularly limited, and (1) an epoxy-based cured resin or other liquid or semi-solid adhesive within the usable life is used. (2) A method of laminating and coating a gas barrier film using a film-like (hot melt) adhesive, and (3) Applying a liquid such as a latex or an emulsion containing a gas barrier material. And a method of spraying, and (4) a method of immersing a styrenic resin foam in a liquid such as a latex or an emulsion containing a gas barrier substance.

As the blowing agent used in the present invention, a saturated hydrocarbon having 3 to 5 carbon atoms is used. Specific examples of the saturated hydrocarbon having 3 to 5 carbon atoms include propane, n-butane, i-butane, n-pentane, i-pentane, and cyclopentane.
Among these, propane, n-butane, i-butane, cyclopentane or a mixture thereof is preferable in terms of foamability and heat insulation.
In the present invention, a compound other than a saturated hydrocarbon having 3 to 5 carbon atoms may be used in combination as a foaming agent, specifically, a non-halogen foaming agent described in JP-A-2004-331964, Trifluoromethane (HFC-23: CHF ₃ ), difluoromethane (HFC-32: CH ₂ F ₂ ), 1,1,1,2,2-pentafluoroethane (HFC-125: CHF ₂ CF ₃ ), 1, 1,1,2-tetrafluoroethane (HFC-134a: CH ₂ FCF ₃ ), 1,1,1-trifluoroethane (HFC-143a: CH ₃ CF ₃ ), 1,1-difluoroethane (HFC-152a: CH ₃ CHF _2), 1,1,1,2,3,3,3- heptafluoropropane _{(HFC-227ea: CF 3 CHFCF} 3), 1,1,1,3,3,3- Hekisafuruo Propane _{(HFC-236fa: CF 3 CH} 2 CF 3), 1,1,2,2,3- pentafluoropropane _{(HFC-245ca: CH 2 FCF} 2 CHF 2), 1,1,1,2,2- Pentafluoropropane (HFC-245cb: CF ₃ CF ₂ CH ₃ ), 1,1,1,3,3-pentafluoropropane (HFC-245fa: CF ₃ CH ₂ CHF ₂ ), 1,1,1,3 Hydrofluorocarbons such as 3-pentafluorobutane (HFC-365mfc: CF ₃ CH ₂ CF ₂ CH ₃ ) can be used, and these can be used as appropriate. Among these, it is preferable to use dimethyl ether, water, carbon dioxide, hydrofluorocarbon and the like in terms of foaming properties, heat insulating properties, and the like.

  In the production of the styrene resin foam of the present invention, the amount of the foaming agent to be added or injected into the styrene resin is appropriately changed according to the setting value of the expansion ratio, etc. The total amount is preferably 1 to 20 parts by weight with respect to 100 parts by weight of the styrene resin. In particular, from the viewpoint of heat insulation, the saturated hydrocarbon having 3 to 5 carbon atoms is more preferably 2 to 10 parts by weight. When the amount of the foaming agent added is less than 1 part by weight, the foaming ratio is low, and the characteristics such as light weight and heat insulation as foams may be difficult to be exhibited. On the other hand, when the amount exceeds 20 parts by weight, foaming is caused by an excessive amount of foaming agent. There may be defects such as voids in the body, and flame retardancy may be reduced depending on the type of foaming agent.

  The styrenic resin used in the present invention is not particularly limited, and can be obtained from, for example, a styrene homopolymer obtained only from a styrene monomer, a styrene monomer, a monomer copolymerizable with styrene, or a derivative thereof. Specific examples include random, block or graft copolymers, post-brominated polystyrene, modified polystyrene such as rubber-reinforced polystyrene, and the like. From the viewpoint of foamability, styrene homopolymer is most preferable. These may be used alone or in combination of two or more.

  Specific examples of the monomer copolymerizable with styrene include those described in JP-A-2004-331964.

  In the present invention, it is preferable to add a flame retardant to a styrene resin foam, an epoxy curable resin, or a gas barrier material to impart flame retardancy to the resulting composite foam. There are no particular restrictions on the flame retardant used for such purposes, and a generally known flame retardant such as a halogen flame retardant, a phosphorus flame retardant, a silica flame retardant, or a nitrogen flame retardant is appropriately selected. Use it.

In particular, it is important to make a styrene resin foam as a base material flame retardant when used as a building material or the like. However, in making a styrene resin foam flame retardant, it is preferable to use a halogen flame retardant. .
Specific examples of such halogen flame retardants include those described in JP-A-2004-331964. From the viewpoint of flame retardancy, hexabromocyclododecane, tetrabromocyclooctane, tetrabromobisphenol A Bis (2,3-dibromopropyl ether) and tris (2,3-dibromopropyl) isocyanurate are more preferable.

  The content of the halogen-based flame retardant in the styrene resin foam is an additive having a foaming agent addition amount, a foam density, and a flame retardant synergistic effect so that the flame retardancy specified in JIS A9511 measuring method A can be obtained. Although it is suitably adjusted according to the type or addition amount of the agent and the like, it is preferably 0.1 to 20 parts by weight, more preferably 1 to 15 parts by weight, with respect to 100 parts by weight of the styrenic resin. More preferably, it is 2 to 12 parts by weight. When the content of the halogen-based flame retardant is less than 0.1 parts by weight, it is difficult to obtain good characteristics such as flame retardancy, which is the object of the present invention, as a foam. When it exceeds, the heat resistance and surface property of the foam obtained, stability at the time of foam production, etc. may be lost.

  In the present invention, for the purpose of improving the flame retardancy of the styrene resin foam, a compound exhibiting a synergistic effect with the halogen flame retardant described above may be added. Examples of the compound exhibiting a synergistic effect with such a halogen flame retardant include iron-containing compounds, phosphorus-containing compounds, nitrogen-containing compounds, boron-containing compounds, sulfur-containing compounds and the like. Phosphorus-containing compounds, nitrogen-containing compounds, boron-containing compounds, sulfur-containing compounds and the like described in JP-A-2003-327738 may be used.

  On the other hand, in the flame-retarding of the epoxy-based cured resin, the halogen flame retardant described above, the phosphorus-containing compound, the nitrogen-containing compound, the boron-containing compound, and the sulfur-containing compound described in JP-A-2003-327738 are used alone, or It can be used in combination to make it flame retardant. Among these, it is more preferable to use a combination of two or more halogen flame retardants, phosphorus-containing compounds, nitrogen-containing compounds, and boron-containing compounds.

  When water is used as the foaming agent for the styrene resin foam, it is preferable to use a water-absorbing substance capable of absorbing water at the same time. In such a case, relatively small bubbles (small bubbles) mainly having a bubble diameter of 0.25 mm or less and relatively large bubbles (large bubbles) having a bubble diameter of about 0.3 to 1 mm are contained in the foam. A styrene resin foam having a characteristic cell structure mixed in a shape is obtained. The styrenic resin foam thus obtained has improved heat insulation performance, and in the composite foam in which such a styrene resin foam is laminated with an epoxy-based cured resin, the heat insulation performance is improved. Since deterioration with time is suppressed as it is, a more preferable form is obtained. Furthermore, when water is used as the foaming agent, the foam obtained by the generation of large bubbles can be easily thickened at a low density, and the moldability of the styrene resin foam can be improved. However, it is preferable to use water as a foaming agent.

  Specific examples of the water-absorbing substance include those described in JP-A-2004-331964, and these may be used as appropriate.

  In the present invention, if necessary, various flame retardant aids, silica, talc, calcium silicate, wollastonite, kaolin, clay, mica, zinc oxide, titanium oxide, as long as the effects of the present invention are not impaired. Inorganic compounds such as calcium carbonate, processing aids such as sodium stearate, magnesium stearate, barium stearate, liquid paraffin, olefin wax, stearylamide compound, phenolic antioxidant, phosphorus stabilizer, nitrogen stabilizer Additives such as a colorant such as a light-resistant stabilizer such as an agent, a sulfur-based stabilizer, benzotriazoles and hindered amines, a flame retardant other than those described above, an antistatic agent, and a pigment.

  In the styrene resin foam used in the present invention, other additives such as styrene resin and halogen flame retardant are supplied to heating and melting means such as an extruder, and the foaming agent is added under high pressure conditions at any stage. It is produced by adding to a styrenic resin, forming a fluid gel, cooling to a temperature suitable for extrusion foaming, and extruding and foaming the fluid gel through a die to a low pressure region to form a foam.

  There are no particular restrictions on the heating temperature, melt kneading time, and melt kneading means when heating and kneading the styrene resin and additives such as a foaming agent.

  The heating temperature may be equal to or higher than the temperature at which the styrenic resin used melts, but is preferably a temperature at which molecular degradation of the resin due to the influence of a flame retardant is suppressed as much as possible, for example, about 150 to 260 ° C.

  The melt-kneading time varies depending on the amount of extrusion per unit time, the melt-kneading means, etc., and thus cannot be determined in general. However, the time required for uniformly dispersing and mixing the styrene-based resin and the foaming agent is appropriately selected.

The melt kneading means is, 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 degradation of the resin as much as possible, it is preferable to use a low shear type screw for the screw shape.
There is no particular restriction on the foam molding method, but for example, a plate having a large cross-sectional area using a molding die and a molding roll in which a foam obtained by releasing pressure from the slit die is placed in close contact with or in contact with the slit die. A general method of forming a foam can be used.

  There is no restriction | limiting in particular in the thickness of the styrene resin foam used by this invention, According to a use, it selects suitably. For example, in the case of a heat insulating material used for a building material or the like, in order to give preferable heat insulating properties, bending strength and compressive strength, the thickness is not as thin as a sheet but as a normal plate. Is preferable, usually 10 to 150 mm, preferably 20 to 100 mm.

The density of the styrenic resin foam used in the present invention is 15 to 50 kg / m ³ , more preferably 20 to 50 kg / m ³ in order to give light weight and excellent heat insulation, bending strength and compressive strength. It is preferable that it is 25 to 35 kg / m ³ . If the density is less than 15 kg / m ³ , the mechanical properties such as compressive strength tend to decrease, and if it exceeds 50 kg / m ³ , the heat insulation tends to decrease and it is difficult to say that it is lightweight. It becomes difficult.

  Next, although the composite foam of this invention is demonstrated still in detail based on an Example, this invention is not restrict | limited only to this Example. Unless otherwise specified, “%” represents “% by weight”.

In the examples and comparative examples, the following compounds were used.
A: Styrene resin A-1: Polystyrene (G9401 manufactured by PS Japan Co., Ltd.)
B: Halogen-based flame retardant B-1: Hexabromocyclododecane (SAYTEX HP-900 manufactured by ALBEMALLE CORPORATION)
B-2: Tetrabromobisphenol A-bis (2,3-dibromopropyl ether) (fire guard 3100 manufactured by Teijin Chemicals Ltd.)
B-3: Tris (2,3-dibromopropyl) isocyanurate (TAIC-6B manufactured by Nippon Kasei Co., Ltd.)
C: Phosphorus-containing compound C-1: Triphenyl phosphate (TPP manufactured by Daihachi Chemical Industry Co., Ltd.)
D: Foaming agent D-1: Propane (odorless propane manufactured by Iwatani Corporation)
D-2: Isobutane (isobutane manufactured by Mitsui Chemicals, Inc.)
D-3: Cyclopentane (cyclopentane manufactured by Taiyo Liquefied Gas Co., Ltd.)
E: Other foaming agents E-1: Dimethyl ether (dimethyl ether manufactured by Mitsui Chemicals, Inc.)
E-2: Water (Settsu City tap water)
F: Other additives F-1: Talc (Talcan powder manufactured by Hayashi Kasei Co., Ltd.)
F-2: Barium stearate (barium stearate manufactured by Sakai Chemical Industry Co., Ltd.)
F-3: Bentonite (Bengel Bright 11 manufactured by Hojun Co., Ltd.)
F-4: AEROSIL (Nippon Aerosil Co., Ltd., AEROSIL)
F-5: Stabilizer (IRGANOX B911 manufactured by Ciba Specialty Chemicals Co., Ltd. (hindered phenol antioxidant IRGANOX1076: octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) Phosphorus stabilizer IRGAFOS 168: 1: 1 mixture of tris (2,4-di-t-butylphenyl) phosphite)
G: Laminated coating material G-1: Epoxy-based cured resin (Bond Quick Mender manufactured by Konishi Co., Ltd., main component main component: modified epoxy resin, curing agent main component: polythiol, main component and curing agent have a viscosity of about 200 Pascal / second, Specific gravity about 1.5)
G-2: Epoxy-based curable resin (Bond E set L manufactured by Konishi Co., Ltd.), main component main component: modified epoxy resin, curing agent main component: modified polyamide resin, main component and curing agent have viscosities of about 3 to 4 Pascal / second, Specific gravity 1)
G-3: Epoxy curing resin (main component main component: Asahi Denka Kogyo Co., Ltd. Adeka Sizer EP-13 (bisphenol A diglycidyl ether), curing agent main component: modified polyamide resin (Konishi Co., Ltd. Bond E set) L curing agent, viscosity about 3-4 pascal / second), specific gravity about 1)
G-4: Phenolic curable resin (Dainippon Ink & Chemicals, Inc., main component: Phenolite MD-3003, viscosity of about 0.1-0.2 Pascal / second, curing agent: Catalyst TD-473 Resin specific gravity 1)
G-5: Urethane-based cured resin (Cemedine UM700, one component, resin specific gravity about 1)
H: Gas barrier material H-1: Nylon film (Kojin Cobarrier ONY, manufactured by Kojin Co., Ltd., thickness 25 micrometers)
H-2: Polyacrylonitrile film (Zeklon, Mitsui Chemicals, Inc., thickness 30 micrometers)
H-3: Eval (ethylene-vinyl alcohol copolymer) film (EF-XL, manufactured by Kuraray Co., Ltd., thickness 15 micrometers)
H-4: Skin layer of styrene resin foam surface (styrene resin composition)
Evaluation / measurement methods for the obtained foam are as follows.

(1) Foam density After the extruded foam was cut into a rectangular parallelepiped of about 200 mm x 100 mm x 25 mm, this weight was measured, and the vertical, horizontal and height dimensions were measured with calipers, and the foam density was calculated using the formula:
Foam density (g / cm ³ ) = foam weight (g) ÷ foam volume (cm ³ )
And the unit was expressed in terms of (kg / m ³ ).

(2) Cell diameter of styrene resin foam Using a Sonic digital microscope BS-D8000, an image enlarged 200 times the cross section in the thickness direction of the styrene resin foam was taken into a personal computer. Print this image on A3 paper, draw a straight line equivalent to 1 mm in actual dimension in the thickness direction at any two locations, count the number of bubbles crossing each straight line, and the bubbles in the thickness direction at each location The diameter was calculated according to the following formula.
Bubble diameter = length of straight line 1 mm / number of bubbles crossing the straight line Then, the value of the bubble diameter at two locations was arithmetically averaged to obtain the bubble diameter in the thickness direction.
Similarly, the bubble diameter was calculated | required about the width direction of a foam, and the length direction, respectively, and the arithmetic mean of 3 directions was made into the bubble diameter.

However, for the foam in which small bubbles and large bubbles were mixed, the small bubble size and the large bubble size were measured separately as follows.
Small bubble diameter: In a photograph in which the cross section in the thickness direction of the extruded foam is magnified 200 times, straight lines corresponding to 1 mm in actual dimension are drawn in the thickness direction at any two locations of the sea part in the sea-island structure. The number of bubbles crossing each other was counted, and the bubble diameter in the thickness direction at each location was calculated according to the following formula.
Small bubble diameter = length of straight line 1 mm ÷ number of bubbles crossing straight line Then, the values of small bubble diameters at two locations were arithmetically averaged to obtain a small bubble diameter in the thickness direction.
Similarly, the bubble diameter was determined for each of the width direction and the length direction of the foam, and the arithmetic average of the three directions was defined as the small bubble diameter.
Large cell diameter: In a photograph in which the cross section in the thickness direction of the extruded foam is magnified 50 times, the length in the thickness direction of the island portions scattered in the sea-island structure is randomly selected, and the thickness for each island is selected. The maximum length in the thickness direction was measured, and the large bubble diameter in the thickness direction was determined by arithmetic averaging. Similarly, the bubble diameter was obtained for each of the width direction and the length direction of the foam, and the arithmetic average of the three directions was defined as the large bubble diameter.

(3) Small cell area ratio of styrene resin foams Occupied area ratio of small bubbles with a bubble diameter of 0.25 mm or less per cross-sectional area of the foam in the thickness direction of the foam in which small bubbles and large bubbles are mixed Was determined as follows. Here, a small bubble having a bubble diameter of 0.25 mm or less is a bubble having a circle equivalent diameter of 0.25 mm or less.
(A) Using a scanning electron microscope (manufactured by Hitachi, Ltd., S-450), the cross section in the thickness direction of the foam is magnified 30 times and photographed (the size of the photograph is 100 mm × 90 mm). .
(B) An OHP sheet is placed on the photographed photograph, and a portion corresponding to a bubble having a diameter in the thickness direction larger than 7.5 mm (corresponding to a bubble having an actual size larger than 0.25 mm) is blackened on the photograph. Paint with ink and copy (primary processing).
(C) The primary processing image is taken into an image processing apparatus (PIAS-II, manufactured by Pierce Co., Ltd.), and whether or not the dark color portion and the light color portion are painted with black ink is identified.
(D) Of the dark-colored portion, the portion corresponding to the area of a circle having a diameter of 7.5 mm or less, that is, the diameter in the thickness direction is long, but the area is only the area of a circle having a diameter of 7.5 mm or less. The portion is lightened and the dark portion is corrected.
(E) Using “FRACTAREA (area ratio)” in the image analysis calculation function, the area ratio of the bubble diameter of 7.5 mm or less (light color portion divided by shading) in the entire image is obtained by the following equation.
Occupied area ratio of small bubbles (%) = (1-area of dark portion / area of entire image) × 100
(4) Thermal conductivity The thermal conductivity of the composite foam was measured according to JIS A9511. For measurement, HC-074 manufactured by Eihiro Seiki was used, and three cuboidal test pieces of about 300 mm x 100 mm x 25 mm were cut out from the styrene resin foam, and an epoxy cured resin was laminated and coated on them (all three cut out) In the same manner, the three laminated coating pieces were arranged side by side and set in a shape of about 300 mm × 300 mm × 25 mm on HC-074 and measured. In addition, it carried out about the foam which passed the 1st day (the next day of a lamination | stacking coating process) and 180 days after the lamination | stacking coating process.

(5) Measurement of foaming agent and amount of air in foam Using a gas chromatograph (GC-9A, manufactured by Shimadzu Corporation), the center of the composite foam 180 days after the laminate coating treatment (styrene resin foaming) The body part) was cut out, and the remaining amount relative to about 1 g of the styrene resin foam was analyzed. The obtained value was converted to the number of parts by weight with respect to 100 parts by weight of the styrene resin foam for the foaming agent. Air was converted to partial pressure.

(6) Average thickness measurement of epoxy-type cured resin The average thickness of the epoxy-type cured resin which carried out lamination | stacking coating was calculated | required as follows.

First, the weight of the applied epoxy-based cured resin is calculated from the weight of the styrene-based resin foam before coating and the weight after the epoxy-based cured resin is applied to the styrene-based resin foam and left to dry at room temperature for one day. did. Next, the average thickness was calculated according to the following formula using the specific gravity of the epoxy-based cured resin.
Average thickness of epoxy cured resin = weight of applied epoxy cured resin ÷ (applied area × specific gravity of epoxy cured resin)
Example 1
For 100 parts of polystyrene (A-1), 3 parts of hexabromocyclododecane (B-1) as a halogen flame retardant, 0.5 part of talc (F-1), and barium stearate (F-2) 0 About 70 kg / hr at a rate of about 70 kg / hr to an extruder in which a mixture of 25 parts and 0.3 parts of stabilizer (F-5) was dry blended and the resulting mixture was vertically connected with a diameter of 65 mm and a diameter of 90 mm Supplied with. While the mixture supplied to the extruder having a diameter of 65 mm was kneaded by heating to 200 ° C., a blowing agent composed of 50% propane (D-1) and 50% dimethyl ether (E-1) was used as a styrene-based foaming agent. The resin was press-fitted into the resin from the vicinity of the tip in the extrusion direction of the extruder having a diameter of 65 mm so as to be 8 parts with respect to 100 parts of the resin. Next, it was cooled by an extruder having a diameter of 90 mm connected to an extruder having a diameter of 65 mm, and further the resin temperature was cooled to 120 ° C. by a cooler connected to the extruder having a diameter of 90 mm, and provided at the tip of the cooler. A styrene-based resin foam having a thickness of 50 mm and a width of 150 mm was obtained by extrusion into the atmosphere from a base having a rectangular cross section with a thickness direction of 2 mm and a width direction of 50 mm. The obtained foam had a uniform cell structure, an average cell diameter of 0.20 mm, and a density of 28 kg / m ³ .

  Next, after the resulting styrene resin foam was allowed to cool for about 40 minutes, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the center of the foam, and epoxy cured resin (G -1) was laminated and coated, and a composite foam was obtained 1 hour after extrusion of the styrene resin foam. In the case of lamination coating, the main agent and the curing agent were mixed well at a weight ratio of 1: 1 and then applied with a spatula. The composite foam thus obtained was allowed to stand for 1 day, and then the thermal conductivity was measured (1 day after the laminate coating treatment). Furthermore, the thermal conductivity was also measured after standing for 180 days.

  Regarding the average thickness of the laminated coating of the epoxy cured resin, the total surface area of the laminated coating portion of the rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm, the weight of the epoxy-based cured resin (G-1) used for the laminated coating, and the epoxy It calculated from the specific gravity of a system hardening resin (G-1).

  For the composite foam after standing for 180 days, the amount of foaming agent and the amount of air in the foam cell were measured.

  The results are shown in Table 1.

なお、得られたスチレン系樹脂発泡体の難燃性について、ＪＩＳ Ａ９５１１測定方法Ａに準じて、厚さ１０ｍｍ、長さ２００ｍｍおよび幅２５ｍｍの試験片に切削した後、７日経過した時点で評価したところ、基準を満たした。

In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Examples 2-3)
A styrene resin foam was obtained and a composite foam was obtained in the same manner as in Example 1 except that the type and addition amount of the halogen flame retardant (B) were changed to the values shown in Table 1. Table 1 shows the characteristics of the obtained styrenic resin foam and composite foam.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Comparative Example 1)
A styrene resin foam was obtained in the same manner as in Example 1. However, the laminated coating treatment was not performed, and the thermal conductivity of the next day (1st day) and the 180th day after cutting out a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was measured, and the next day (1 Day 2) was also evaluated for flammability.
The results of the above measurement and evaluation are shown in Table 1.
In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

  As is clear from comparison between Examples 1 to 3, which are examples of the present invention, and Comparative Example 1, it can be seen that according to the present invention, deterioration of the thermal conductivity with time is suppressed.

Example 4
For 100 parts of polystyrene (A-1), 3 parts of hexabromocyclododecane (B-1) as a halogen-based flame retardant, 1 part of triphenyl phosphate (C-1) as a phosphorus-containing compound, and further talc (F-1 ) 0.5 parts, a mixture consisting of 0.25 parts of barium stearate (F-2) and 0.3 parts of stabilizer (F-5) was dry blended, and the resulting mixture was mixed with an extruder having a diameter of 65 mm An extruder having a diameter of 90 mm was supplied to an extruder connected vertically, at a rate of about 70 kg / hr. While the mixture supplied to the extruder having a diameter of 65 mm was kneaded by heating to 200 ° C., a foaming agent composed of 67% isobutane (D-2) and 33% dimethyl ether (E-1) was used as a styrene-based foaming agent. The resin was press-fitted into the resin from near the front end in the extrusion direction of the extruder having a diameter of 65 mm so as to be 6 parts with respect to 100 parts of the resin. Next, it is cooled with an extruder with a diameter of 90 mm connected to an extruder with a diameter of 65 mm, and further the resin temperature is cooled to 120 ° C. with a cooler connected to an extruder with a diameter of 90 mm, and the thickness provided at the tip of the cooler A styrene resin foam having a thickness of 50 mm and a width of 150 mm was obtained by extrusion into the atmosphere from a base having a rectangular cross section of 2 mm in the width direction and 50 mm in the width direction. The obtained foam had a uniform cell structure, an average cell diameter of 0.19 mm, and a density of 30 kg / m ³ .

  Next, after the resulting styrene resin foam was allowed to cool for about 40 minutes, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the center of the foam, and epoxy cured resin (G -1) was laminated and coated, and a composite foam was obtained 1 hour after extrusion of the styrene resin foam. In the case of lamination coating, the main agent and the curing agent were mixed well at a weight ratio of 1: 1 and then applied with a spatula.

  The composite foam thus obtained was allowed to stand for 1 day, and then the thermal conductivity was measured (1 day after the laminate coating treatment). Furthermore, the thermal conductivity was also measured after standing for 180 days.

  In addition, about the laminated coating thickness of an epoxy cured resin, the total surface area of the laminated coating part of a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm, the weight of the epoxy cured resin (G-1) used for the laminated coating, and the epoxy type It calculated from specific gravity of cured resin (G-1).

  For the composite foam after standing for 180 days, the amount of foaming agent and the amount of air in the foam cell were measured.

  The results are shown in Table 1.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Examples 5-6)
A styrene resin foam was obtained and a composite foam was obtained in the same manner as in Example 4 except that the type and addition amount of the halogen flame retardant (B) were changed to the values shown in Table 1. Table 1 shows the characteristics of the obtained styrenic resin foam and composite foam.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Comparative Example 2)
A styrene resin foam was obtained in the same manner as in Example 4. However, the thermal conductivity was measured on the next day (first day) and the 180th day after cutting out a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm without carrying out the laminated coating treatment.

  The results of the above measurement and evaluation are shown in Table 1.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

  As is clear by comparing Examples 4 to 6, which are examples of the present invention, and Comparative Example 2, it can be seen that according to the present invention, deterioration of the thermal conductivity over time is suppressed.

(Example 7)
For 100 parts of polystyrene (A-1), 3 parts of hexabromocyclododecane (B-1) as a halogen-based flame retardant, 1 part of triphenyl phosphate (C-1) as a phosphorus-containing compound, and further talc (F-1 ) 0.2 parts, barium stearate (F-2) 0.25 parts, bentonite (F-3) 1 part, AEROSIL (F-4) 0.1 part, stabilizer (F-5) 0.3 part The resulting mixture was dry blended, and the resultant mixture was fed at a rate of about 70 kg / hr to an extruder in which those having a diameter of 65 mm and a diameter of 90 mm were vertically connected. While the mixture supplied to the extruder having a diameter of 65 mm was kneaded while heating to 200 ° C., 57% isobutane (D-2), 29% dimethyl ether (E-1) and water (E-2) Near the tip of the 65 mm diameter extruder (connected to the end opposite to the die of the 90 mm diameter extruder) so that the foaming agent comprising 14% is 7 parts with respect to 100 parts of the styrene resin. The resin was press-fitted into the resin from the side end). Next, it is cooled by an extruder having a diameter of 90 mm connected to this, and further the resin temperature is cooled to 120 ° C. by a cooler connected to this, and the thickness direction is 2 mm and the width direction is 50 mm provided at the tip of this cooler. A styrene-based resin foam having a thickness of 50 mm and a width of 150 mm was obtained by extrusion into the atmosphere from a rectangular cross-section die. The obtained foam has a cell structure in which small bubbles and large bubbles are mixed. The average bubble diameter of small bubbles is 0.07 mm, the average bubble diameter of large bubbles is 0.48 mm, and the small bubble area ratio is The density was 40 kg and the density was 30 kg / m ³ .

  Next, after the resulting styrene resin foam was allowed to cool for about 40 minutes, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the central portion of the foam, and epoxy cured resin (G -1) was laminated and coated, and a composite foam was obtained 1 hour after extrusion of the styrene resin foam. In the case of lamination coating, the main agent and the curing agent were mixed well at a weight ratio of 1: 1 and then applied with a spatula.

  The composite foam thus obtained was allowed to stand for 1 day, and then the thermal conductivity was measured (1 day after the laminate coating treatment). Furthermore, the thermal conductivity was also measured after standing for 180 days.

  In addition, about the laminated coating thickness of an epoxy cured resin, the total surface area of the laminated coating part of a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm, the weight of the epoxy cured resin (G-1) used for the laminated coating, and the epoxy type It calculated from specific gravity of cured resin (G-1).

  For the composite foam after standing for 180 days, the amount of foaming agent and the amount of air in the foam cell were measured.

  Table 2 shows the results of the above measurement and evaluation.

なお、得られたスチレン系樹脂発泡体の難燃性について、ＪＩＳ Ａ９５１１測定方法Ａに準じて、厚さ１０ｍｍ、長さ２００ｍｍおよび幅２５ｍｍの試験片に切削した後、７日経過した時点で評価したところ、基準を満たした。

In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Examples 8 to 15)
Except the halogen flame retardant (B), the foaming agent (D), the type and amount added, the type of the laminated coating material (G), and the average thickness, the values shown in Table 2 were used. A styrene resin foam was obtained and a composite foam was obtained. Table 2 shows the characteristics of the obtained styrenic resin foam and composite foam. (Epoxy-based cured resins (G-2) and (G-3) were both mixed with a main agent and a curing agent at a weight ratio of 1: 1 as in (G-1).)
In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. As a result, the criteria were satisfied except for Example 15. Example 15 was burnt down.
(Example 16)
A styrenic resin foam was obtained in exactly the same manner as in Example 7, and allowed to cool for about 40 minutes. Then, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the center of the foam and left for another 18 hours. All six surfaces were coated with an epoxy-based cured resin (G-1). That is, a composite foam was obtained 18 hours after the styrene resin foam was extruded. Evaluation of thermal conductivity and combustibility was performed in the same manner as in Example 7.
Table 2 shows the results of the above measurement and evaluation.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Example 17)
A styrenic resin foam was obtained in exactly the same manner as in Example 7, and allowed to cool for about 40 minutes. Then, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the central portion of the foam and immediately 300 mm × 100 mm 2 The epoxy cured resin (G-1) was laminated and coated only on a total of four surfaces of the surface and two surfaces of 300 mm × 25 mm, and a composite foam was obtained within 1 hour after extrusion of the styrene resin foam. Evaluation of thermal conductivity and combustibility was performed in the same manner as in Example 7.
Table 2 shows the results of the above measurement and evaluation.
In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Example 18)
A styrenic resin foam was obtained in exactly the same manner as in Example 7, and allowed to cool for about 40 minutes. Then, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the central portion of the foam and immediately 300 mm × 100 mm 2 An epoxy-based cured resin (G-1) was laminated and coated only on the surface, and a composite foam was obtained within 1 hour after extrusion of the styrene-based resin foam. Evaluation of thermal conductivity and combustibility was performed in the same manner as in Example 7.
Table 2 shows the results of the above measurement and evaluation.
In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Example 19)
A styrenic resin foam was obtained in exactly the same manner as in Example 7, and allowed to cool for about 40 minutes. Then, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the central portion of the foam, and immediately, 300 mm × 100 mm 1 An epoxy-based cured resin (G-1) was laminated and coated only on the surface, and a composite foam was obtained within 1 hour after extrusion of the styrene-based resin foam. Evaluation of thermal conductivity and combustibility was performed in the same manner as in Example 7. However, when the three laminated coating pieces were arranged at the time of measuring the thermal conductivity, the surfaces subjected to the laminated coating treatment were set to be the same surface.
Table 2 shows the results of the above measurement and evaluation.
In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Example 20)
The styrenic resin foam was allowed to cool for about 40 minutes in exactly the same manner as in Example 7, and then cut out to a length of about 310 mm along the extrusion direction, and the surfaces other than the cut out two surfaces were left uncut. In addition, the skin layer which consists of a polystyrene resin composition existed in thickness of about 20-100 micrometers in the outermost layer of surfaces other than the cut-out 2 surface.

Next, this skin-attached styrene resin foam was laminated and coated with an epoxy-based cured resin (G-1) in exactly the same manner as in Example 7, and the composite foam was formed in 1 hour after extrusion of the styrene resin foam. Obtained.
After leaving the composite foam thus obtained for 1 day, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the center of the composite foam, and the thermal conductivity was immediately measured (after laminating coating treatment 1 Day). Furthermore, another composite foam obtained in the same manner was cut into a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm on the 180th day, and the thermal conductivity was measured immediately.

  In addition, about the laminated coating thickness of an epoxy cured resin, it calculates from the total surface area of a laminated coating part, the weight of the epoxy-type cured resin (G-1) used for laminated coating, and the specific gravity of an epoxy-type cured resin (G-1). did.

  For the composite foam after standing for 180 days, the amount of foaming agent and the amount of air in the foam cell were measured.

  Table 2 shows the results of the above measurement and evaluation.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Example 21)
A styrenic resin foam was obtained in exactly the same manner as in Example 7, and allowed to cool for about 40 minutes. Then, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the central portion of the foam, and epoxy was immediately applied to all six surfaces. In order to laminate and coat the system-cured resin (G-1) with a spatula, before curing, the nylon film (H-1) is further coated on all six surfaces of the epoxy-based cured resin (G-1). (In other words, the nylon film layer is outside of the epoxy-based cured resin layer), and a composite foam was obtained 1 hour after the extrusion of the styrene-based resin foam. Evaluation of thermal conductivity and combustibility was performed in the same manner as in Example 7.

  Table 2 shows the results of measurement and evaluation of the composite foam.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Examples 22 to 23)
A composite foam was obtained in exactly the same manner as in Example 21, except that the polyacrylonitrile film (H-2) and the eval film (H-3) were used instead of the nylon film (H-1).

  Table 2 shows the results of measurement and evaluation of the composite foam.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Example 24)
A styrenic resin foam was obtained in exactly the same manner as in Example 7, and allowed to cool for about 40 minutes. Then, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the center of the foam and allowed to stand for 3 days. Three days later, an epoxy cured resin (G-1) and a nylon film (H-1) were laminated and coated in the same manner as in Example 21 to obtain a composite foam.

  Table 2 shows the results of measurement and evaluation of the composite foam.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Example 25)
A styrenic resin foam was obtained in exactly the same manner as in Example 7 and allowed to cool for about 40 minutes. After that, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the center of the foam, and immediately nylon was applied to all six sides. The film (H-1) was laminated and coated. At this time, a hot melt type film (Erphan NT-120 manufactured by Nippon Matai Co., Ltd.) is first placed on the entire surface of the rectangular parallelepiped test piece, and a nylon film (H-1) is stacked thereon, and then a nylon film (H -1) It was bonded by pressing with an iron heated to about 120 ° C. from above.

  Immediately thereafter, all six surfaces were laminated and coated with the epoxy cured resin (G-1) in the same manner as in Example 7 (that is, the nylon film layer was between the styrene resin foam and the epoxy cured resin layer), and styrene. A composite foam was obtained 1 hour after the extrusion of the resin foam.

  Table 2 shows the results of measurement and evaluation of the composite foam.

In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.
(Comparative Example 3)
A styrene resin foam was obtained in exactly the same manner as in Example 7. However, the thermal conductivity was measured on the next day (first day) and the 180th day after cutting out a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm without carrying out the laminated coating treatment.

  Table 3 shows the results of measurement and evaluation of the above styrene resin foam.

なお、得られたスチレン系樹脂発泡体の難燃性について、ＪＩＳ Ａ９５１１測定方法Ａに準じて、厚さ１０ｍｍ、長さ２００ｍｍおよび幅２５ｍｍの試験片に切削した後、７日経過した時点で評価したところ、基準を満たした。

In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Comparative Example 4)
A styrene resin foam was obtained in exactly the same manner as in Example 7 except that no halogen flame retardant was used. However, the thermal conductivity was measured on the next day (first day) and the 180th day after cutting out a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm without carrying out the laminated coating treatment.

  Table 3 shows the results of measurement and evaluation of the above styrene resin foam.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. When it was done, it burned down.

(Comparative Example 5)
The styrenic resin foam was allowed to cool for about 40 minutes in the same manner as in Example 7, and then cut out to a length of about 310 mm along the extrusion direction, and the other surfaces than the cut out surfaces were left as they were. In addition, the skin layer which consists of a polystyrene resin composition existed in the thickness of about 20-100 micrometers on surfaces other than the cut-out 2 surface.
Next, without carrying out the laminate coating treatment with this skin-attached styrene resin foam, after leaving it for one day, a cuboid test piece of about 300 mm × 100 mm × 25 mm was cut out from the central portion of the skin-attached styrene resin foam, Immediately the thermal conductivity was measured. Further, after leaving for 180 days, it was left as a styrene resin foam with skin, cut into a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm on the 180th day, and immediately measured for thermal conductivity.
Table 3 shows the results of measurement and evaluation of the above styrene resin foam.
In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Comparative Example 6)
A styrenic resin foam was obtained in exactly the same manner as in Example 7, and allowed to cool for about 40 minutes. Then, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the central portion of the foam, and phenol on all six sides immediately. The system cured resin (G-4) was laminated and coated, and a composite foam was obtained in 1 hour after the extrusion of the styrene resin foam. In the case of lamination coating, the main agent and the curing agent were mixed well at a weight ratio of 100: 15 and then applied with a spatula.

  Subsequent evaluation was performed in the same manner as in Example 7.

  Table 3 shows the results of the measurement and evaluation of the composite foam.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

(Comparative Example 7)
A styrenic resin foam was obtained in exactly the same manner as in Example 7, and allowed to cool for about 40 minutes. Then, a rectangular parallelepiped test piece of about 300 mm × 100 mm × 25 mm was cut out from the central portion of the foam, and immediately urethane on all six surfaces. The system cured resin (G-4) was laminated and covered with a spatula, and a composite foam was obtained 1 hour after the extrusion of the styrene resin foam.

  Subsequent evaluation was performed in the same manner as in Example 7.

  Table 3 shows the results of the measurement and evaluation of the composite foam.

  In addition, about the flame retardance of the obtained styrenic resin foam, after cutting into a test piece having a thickness of 10 mm, a length of 200 mm and a width of 25 mm in accordance with JIS A9511 measuring method A, evaluation was made when 7 days had passed. I met the criteria.

  As is clear by comparing Examples 7 to 25 and Comparative Examples 3 to 7 which are examples of the present invention, according to the present invention, deterioration of the thermal conductivity over time is suppressed, and even better flame retardancy is achieved. It turns out that it expresses.

  Further, as apparent from comparison between Example 7 and Examples 20 to 25, it is understood that when the gas barrier material is used in combination, deterioration of the thermal conductivity with time is further suppressed.

Claims (10)

  Composite foam formed by laminating and coating an epoxy cured resin that cures at room temperature on the surface of a styrene resin foam obtained by extruding and foaming a styrene resin composition together with a foaming agent composed of a saturated hydrocarbon having 3 to 5 carbon atoms. body.   The composite foam according to claim 1, wherein the epoxy-based cured resin comprises an epoxy-based compound as a main agent and a curing agent.   The composite foam according to claim 2, wherein the epoxy compound as the main agent is bisphenol A type diglycidyl ether and / or bisphenol A type epoxy resin.   The composite foam according to claim 2, wherein the curing agent contains a compound selected from the group consisting of polyamide, polyamine, polyamidoamine, and polythiol.   The composite foam according to any one of claims 1 to 4, wherein the average thickness of the laminated epoxy-based cured resin is 0.1 to 500 micrometers.   The composite foam according to any one of claims 1 to 5, wherein a gas barrier material is laminated and coated on the surface of the styrenic resin foam.   The gas barrier material contains a resin selected from the group consisting of a polyamide-based resin, a polyacrylonitrile-based resin, a polystyrene-based resin, a polyvinylidene chloride-based resin, and an ethylene-vinyl alcohol copolymer. The composite foam described.   The composite foam according to any one of claims 1 to 7, wherein the partial pressure of air contained in the bubbles (cells) of the styrene resin foam is 50 kilopascals or less.   The partial pressure of the air contained in the bubbles (cells) of the styrene resin foam obtained by extruding and foaming the styrene resin composition with a blowing agent composed of a saturated hydrocarbon having 3 to 5 carbon atoms is 50 kilopascals or less. At the time, a method for producing a composite foam obtained by laminating and coating an epoxy-based cured resin on the surface of the styrene-based resin foam.   A method for producing a styrenic resin foam obtained by extruding a styrenic resin composition together with a foaming agent comprising a saturated hydrocarbon having 3 to 5 carbon atoms, which is extruded from the extruder into the atmosphere within 12 hours. A method for producing a composite foam obtained by laminating and coating an epoxy-based cured resin on the surface of the styrene resin foam.