JP2005213440A - Foamed styrene resin and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foamed styrene resin having extremely high flame-retardance and heat-insulation, enabling stable production and useful especially as a heat-insulating material for building by using a foaming agent having excellent environmental friendliness. <P>SOLUTION: The foamed styrene resin is produced by adding a foaming agent to a molten styrene resin and subjecting the product to extrusion foaming process. The foamed styrene resin is composed of 100 pts. wt. of a styrene resin, a foaming agent composed of (a) a 3-5C saturated hydrocarbon, (b) one or more compounds selected from methyl chloride, ethyl chloride and dimethyl ether and (c) a 3rd foaming agent component, a flame-retardant containing (d) a halogen-based flame-retardant and (e) a phosphorus-based flame-retardant, and a bubble diameter regulator composed of (f) a boric acid metal salt. The density of the foamed product is 20-50 kg/m<SP>3</SP>and the bubbles of the foamed material is composed of small bubbles and large bubbles. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a styrenic resin foam excellent in environmental compatibility, heat insulation and flame retardancy, and a method for producing the same.

  A method of continuously producing a foam by melting a styrene resin with an extruder or the like, then adding a foaming agent, cooling it, and extruding it into a low pressure region is already known (for example, patents). Document 1, Patent Document 2), and a method using chlorofluorocarbons as a foaming agent are also known (for example, Patent Document 3, Patent Document 4).

  However, chlorofluorocarbons are desired to be replaced if possible from the viewpoint of protecting the ozone layer.

  Styrenic resin foam using a blowing agent other than chlorofluorocarbons and a production method as styrene resin using propane, butane or a mixture thereof, or the hydrocarbon and methyl chloride, ethyl chloride or a mixture thereof as a blowing agent A foam and a manufacturing method thereof are disclosed in Patent Document 5. Furthermore, in Patent Document 5, in order to satisfy the flame retardancy specified in JIS A9511, 1 to 3% by weight of hexabromocyclododecane or tetrabromobisphenol A is used, and residual gas in the foam of propane and butane as blowing agents. It is disclosed that the amounts are adjusted to 3.5 wt% or less and 2.0 wt% or less, respectively.

  However, in the foam without using the chlorofluorocarbons obtained in the invention described in Patent Document 5, in order to adjust the residual gas amount of propane and butane to the above amount, Processing such as limiting the amount of addition or storing for a long period of time until the foaming agent is reduced after the production of the foam is required, and further, there are problems such as inferior production stability and productivity during extrusion foaming.

Furthermore, in the amount of propane and butane in the foam obtained by the invention described in Patent Document 5 that does not use chlorofluorocarbons, highly heat-insulating materials such as three types of extruded polystyrene foam heat insulating plates defined in JIS A9511 are used. It is difficult to obtain a foam having properties. According to the study by the present inventors, it is preferable to leave more saturated hydrocarbon compounds such as propane and butane in order to obtain a foam having high heat insulation properties. However, if the foam density is in the range of 20 to 40 kg / m ³ , 4.0% by weight or more for propane and 2.5% by weight or more for butanes with respect to the weight of the foam. It is preferable to leave it, and it is considered that it is particularly preferable to leave 3.0% by weight or more of butanes. However, when a large amount of relatively flammable compounds such as aliphatic hydrocarbons typified by propane and butane remain, hexabromocyclododecane and tetrabromobisphenol A are added in an amount of 1.0 to If only 3.0% by weight is used, the flame retardancy specified in JIS A9511 may not be satisfied. On the other hand, in order to improve the flame retardancy, it is conceivable to increase the amount of the flame retardant to be added, but it is difficult to obtain a stable flame retardancy simply by increasing the amount of addition. In particular, although the styrene resin itself, which is the basic material of the foam, is flame retardant, the tendency that it is easy to ignite hydrocarbons that volatilize from the foam during combustion and it is difficult to suppress combustion is still difficult to solve. Furthermore, an increase in the amount of the flame retardant tends to cause deterioration of foam moldability, and it tends to be difficult to obtain a molded product with satisfactory quality.

  In addition, in general, when adjusting the bubble diameter of the foam, an inorganic porous material typified by talc is often used as the bubble diameter adjusting agent. However, with these conventional bubble diameter adjusting agents, The degree of freedom of setting is limited. For example, when the amount of the conventional cell diameter adjusting agent is increased, the foam structure of the foam, which is easy to cause deterioration of the moldability of the foam and advantageous for obtaining the excellent heat insulation required by the present invention, specifically, the cell It is composed of bubbles having a diameter of 0.25 mm or less and bubbles having a bubble diameter of 0.3 to 1 mm. These bubbles are dispersed in a sea-island shape through the bubble film, and the bubble diameter occupies per foam cross-sectional area is 0.25 mm or less. A foam structure having a bubble area ratio of 10 to 90% (hereinafter, sometimes referred to as a bubble structure composed of large and small bubbles) is not obtained, and a molded product having a desired satisfactory quality is obtained. It tends to be difficult to obtain.

  Also, heat-melting styrene resin, using non-halogen foaming agent as foaming agent, and using halogen flame retardant, borate metal salt, fatty acid metal salt, excellent heat insulation and flame retardant Patent Document 6 discloses a styrenic resin foam excellent in properties and a method for producing the same. However, the foam described in Patent Document 6 does not have a large and small bubble structure advantageous for obtaining the above excellent heat insulating properties, and is still insufficient with respect to the heat insulating properties and needs to be improved. .

  Patent Documents 7 and 8 use a saturated hydrocarbon having 3 to 5 carbon atoms as a foaming agent, and (A) a halogen-based flame retardant, (B) a phosphorus-based flame retardant, and nitrogen containing as a flame retardant. It is described that a styrene resin foam excellent in heat insulation and flame retardancy is produced using at least one of a compound, a metal borate salt, and boron oxide, and the above-described large and small cell structures of the foam are described. Although a cellular structure is also described, there is no mention of applying a metal borate to this particular cellular structure.

Japanese Patent Publication No.31-5393 Japanese Patent Publication No.42-19195 Japanese Patent Publication No.41-672 Japanese Patent Publication No.57-7175 JP-A-10-237210 JP 2001-131323 A International Publication No. 01/030896 Pamphlet International Publication No. 02/051918 Pamphlet

  As described above, it is very difficult to achieve flame retardancy while having high heat insulation performance in a system using saturated hydrocarbons as a blowing agent.

  In addition, means for adjusting the bubble diameter of the foam are limited, and the degree of freedom in setting the bubble diameter is limited.

  Under such circumstances, the problem to be solved by the present invention is to use a foaming agent having a tendency to burn easily and to have high heat insulation performance by adjusting the bubble diameter, and to achieve a high degree of difficulty defined in JIS A9511. An object of the present invention is to provide a styrenic resin foam sufficiently satisfying flammability and a method for producing the same.

  As a result of intensive studies to solve the above problems, the present inventors have used a metal borate as a cell diameter adjusting agent when producing the foam having the specific large and small cell structure required by the present invention. In general, it is possible to adjust the bubble size without increasing the inorganic porous material represented by talc and the like, which is necessary for adjusting the bubble size of the foam, and without inhibiting the specific large and small bubble structure. It became possible and found that excellent heat insulation was obtained.

  Furthermore, in the production of styrene resin foams using hydrocarbons as foaming agents, hydrocarbons can be used as foaming agents by using a halogen-based flame retardant, a phosphorus-based flame retardant, and, if necessary, a nitrogen-containing compound in combination. In spite of the use of methane, it is possible to achieve excellent flame retardancy, and in particular, it is possible to suppress ignition or combustion of hydrocarbons that are volatilized from the foam during combustion, thereby achieving a high degree of difficulty as defined in JIS A9511. It has been found that both flammability and high heat insulation can be achieved.

  Furthermore, it discovered that the heat insulation performance of the foam of this invention can be improved more by using together titanium oxide, especially the titanium oxide surface-treated with the silicon compound.

That is, this invention provides the following styrene resin foam and its manufacturing method.
(1) A styrene resin foam obtained by heating and melting a styrene resin, adding a foaming agent, and extruding and foaming the foaming agent, and a) carbon as a foaming agent with respect to 100 parts by weight of the styrene resin. 2 to 6 parts by weight of at least one saturated hydrocarbon having a number of 3 to 5, b) 1 to 7 parts by weight of at least one compound selected from the group consisting of methyl chloride, ethyl chloride and dimethyl ether, and c) 0.1 to 5 parts by weight of a third component foaming agent (excluding chlorofluorocarbon foaming agent) is used as a flame retardant, and d) at least one selected from halogen flame retardants 0.1 to 6 weights And e) at least one selected from phosphorous flame retardants and 0.1 to 3 parts by weight, and f) at least one selected from metal borate as a cell diameter regulator 0.1 Contains 6 parts by weight and has a foam density of 20 to 20 It was 0 kg / m ^3, and the bubbles of the foam is composed of bubbles of primarily cell diameter 0.25mm or less of the bubble and the bubble diameter 0.3 to 1 mm, dispersed dotted pattern these bubbles through the bubble membrane And the area ratio of the bubbles having a bubble diameter of 0.25 mm or less per cross-sectional area of the foam is 10 to 90%.

(2) The styrenic resin as described in (1) above, wherein the saturated hydrocarbon having 3 to 5 carbon atoms is at least one saturated hydrocarbon selected from the group consisting of propane, n-butane and i-butane. Foam.

(3) The third component foaming agent is at least one inorganic foaming agent selected from the group consisting of water, carbon dioxide and nitrogen, and / or one alcohol selected from methyl alcohol and ethyl alcohol. The styrene resin extruded foam according to the item (1) or (2).

(4) The above (1) to (1), wherein the halogen flame retardant is at least one halogen flame retardant selected from the group consisting of hexabromocyclododecane, tetrabromocyclooctane, and tetrabromobisphenol A bis (allyl ether). The styrene resin foam according to any one of items 3).

(5) The phosphorous flame retardant according to any one of the above (1) to (4), wherein the phosphoric flame retardant is at least one phosphorous flame retardant selected from triphenyl phosphate and tris (tribromoneopentyl) phosphate. Styrenic resin foam.

(6) The styrenic resin according to any one of (1) to (5), wherein the metal borate salt comprises at least one selected from the group consisting of barium borate, magnesium borate, and calcium borate. Foam.

(7) The styrenic resin foam as described in (6) above, wherein the metal borate salt is barium borate.

(8) The above (1) to (7) containing 0.2 to 10 parts by weight of at least one compound selected from the group consisting of bentonite, hectorite and inorganic porous material with respect to 100 parts by weight of styrene resin. The styrene resin foam according to any one of items 1).

(9) The styrenic resin foam according to any one of (1) to (8) above, wherein the third component foaming agent is water.

(10) Further, 0.1 to 5 parts by weight of at least one compound selected from nitrogen-containing compounds selected from the group consisting of cyanuric acid, isocyanuric acid and derivatives thereof is contained with respect to 100 parts by weight of the styrene resin. The styrenic resin foam according to any one of the items (1) to (9), wherein:

(11) The styrene resin foam according to any one of (1) to (10), further containing 0.2 to 6 parts of titanium oxide with respect to 100 parts by weight of the styrene resin.

(12) The styrene resin foam according to (11) above, wherein the titanium oxide is titanium oxide surface-treated with a silicon compound.

(13) Any one of the above items (1) to (12), which does not contain a fluorocarbon foaming agent and has both heat insulation and flame retardancy, which conforms to three types of extruded polystyrene foam heat insulating plates specified in JIS A9511 The styrenic resin foam according to claim 1.

(14) The styrenic resin foam as described in (13) above, wherein the heat insulating property is 0.028 W / mK or less in terms of thermal conductivity.

(15) In the flame retardancy measurement defined in JIS A9511, the flame extinguishes within 3 seconds, the flame disappears, there is no residue, and the combustion limit indication line is not combusted (13) Or the styrene resin foam as described in (14) term.

(16) A method for producing a styrene resin foam in which a styrene resin is heated and melted, a foaming agent is added, and this is extruded and foamed, and as a foaming agent for 100 parts by weight of the styrene resin, a) 2 to 6 parts by weight of at least one saturated hydrocarbon having 3 to 5 carbon atoms, b) 1 to 7 parts by weight of at least one compound selected from the group consisting of methyl chloride, ethyl chloride and dimethyl ether, c 3) 0.1 to 5 parts by weight of a third component foaming agent (excluding a fluorocarbon foaming agent), and as a flame retardant, d) at least one selected from halogenated flame retardants 0.1 to 6 E) at least one selected from 0.1 to 3 parts by weight selected from e) a phosphorus-based flame retardant, and f) at least one selected from metal borate as a cell diameter regulator 0.1 Extruded with ~ 6 parts by weight And foam, the foam density of 20 to 50 kg / m ^3, and the bubbles of the foam is composed of bubbles of primarily cell diameter 0.25mm or less of the bubble and the bubble diameter 0.3 to 1 mm, these bubbles A styrenic resin foam is obtained, which is dispersed in a sea-island shape through a cell membrane and obtains a styrene resin foam in which the area ratio of cells having a cell diameter of 0.25 mm or less per foam cross-sectional area is 10 to 90% Manufacturing method of resin foam.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to manufacture stably the styrene resin foam excellent in environmental compatibility and excellent in a flame retardance and heat insulation. The styrenic resin foam of the present invention is particularly useful for use as a heat insulating material for buildings because of its excellent flame retardancy and heat insulating properties.

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

  Examples of monomers copolymerizable with styrene include methylstyrene, dimethylstyrene, ethylstyrene, diethylstyrene, isopropylstyrene, bromostyrene, dibromostyrene, tribromostyrene, chlorostyrene, dichlorostyrene, and trichlorostyrene. Polyfunctional vinyl compounds such as divinylbenzene, (meth) acrylic compounds such as acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, acrylonitrile, diene compounds such as budadiene or the like Derivatives, unsaturated carboxylic acid anhydrides such as maleic anhydride, itaconic anhydride and the like. These can be used alone or in admixture of two or more.

  Among styrenic resins, styrene homopolymer is preferable from the viewpoint of processability.

  The present invention provides, as a blowing agent, a) at least one compound selected from the group consisting of a saturated hydrocarbon having 3 to 5 carbon atoms, b) methyl chloride, ethyl chloride, dimethyl ether, and c. ) It is characterized by using a third component foaming agent (excluding chlorofluorocarbon foaming agents) in a specific ratio.

  Examples of the saturated hydrocarbon having 3 to 5 carbon atoms used in the present invention include propane, n-butane, isobutane, n-pentane, isopentane, neopentane and the like. Among saturated hydrocarbons having 3 to 5 carbon atoms, 2 are selected from the group consisting of propane, n-butane, and isobutane alone, or propane, n-butane, and isobutane from the viewpoint of foamability and thermal insulation performance of the foam. In the case where a seed or a mixture of three species is preferred and higher thermal insulation performance is desired, n-butane, isobutane alone or a mixture of n-butane and isobutane is more preferred, and when higher thermal insulation performance is desired. Isobutane is most preferred.

  As the third component foaming agent, inorganic foaming agents such as water, carbon dioxide and nitrogen, and alcohols such as methyl alcohol and ethyl alcohol are preferable from the viewpoint of foamability and foam moldability. These can be used alone or in admixture of two or more. From the viewpoint of easily obtaining a specific large and small bubble structure in the present invention, water is more preferable. By using the foaming agent of the third component, not only the specific cell structure of the present invention can be obtained, but also a good plasticizing effect and foaming aid effect can be obtained, the extrusion pressure can be reduced, and the foam can be stably produced. Can be manufactured.

  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 2 to 20 parts by weight with respect to 100 parts by weight of the styrene resin, and more preferably 3 to 18 parts by weight. If the addition amount of the foaming agent is less than the above range, the foaming ratio is low, and the characteristics such as light weight and heat insulation as the resin foam may be difficult to be exhibited. May cause defects such as voids.

  Regarding the addition amount of each foaming agent component, a) the amount of one or two or more saturated hydrocarbons having 3 to 5 carbon atoms is 2 to 6 parts by weight with respect to 100 parts by weight of the styrenic resin, and b ) The amount of at least one compound selected from the group consisting of methyl chloride, ethyl chloride and dimethyl ether is 1 to 7 parts by weight, and c) the amount of the third component blowing agent is 0.1 to 5 parts by weight. . When the amount of the saturated hydrocarbon having 3 to 5 carbon atoms is less than the above range, the heat insulating property of the obtained foam may be inferior. On the other hand, when it exceeds the above range, desired flame retardancy cannot be obtained. Further, if the amount of at least one compound selected from the group consisting of methyl chloride, ethyl chloride, and dimethyl ether is less than the above range, it is necessary to increase the resin temperature in order to reduce the pressure in the extruder, resulting in closed cells. On the other hand, if the amount is larger than the above range, the plasticity is too high, the kneading state of the styrene resin and the foaming agent in the extruder becomes uneven, and the pressure control of the extruder tends to be difficult. If the amount of the third component foaming agent is less than the above range, the specific large and small cell structure in the present invention cannot be obtained, while if it exceeds the above range, the kneading state of the styrene resin and the foaming agent in the extruder is not good. It becomes uniform and the pressure control of the extruder tends to be difficult.

  In the present invention, other foaming agents may be used in addition to the foaming agent components a), b) and c). Such other blowing agents include alcohols such as propyl alcohol, isopropyl alcohol, butyl alcohol, isobutyl alcohol, t-butyl alcohol, diethyl ether, methyl ethyl ether, diisopropyl ether, di n-butyl ether, diisopropyl ether, furan, Ethers such as furfural, 2-methylfuran, tetrahydrofuran, tetrahydropyran, dimethyl ketone, methyl ethyl ketone, diethyl ketone, methyl n-propyl ketone, methyl n-butyl ketone, methyl isobutyl ketone, methyl n-amyl ketone, methyl n-hexyl ketone , Ketones such as ethyl n-propyl ketone, ethyl n-butyl ketone, formic acid methyl ester, formic acid ethyl ester, formic acid propyl ester Butyl formate ester formate, amyl esters, methyl propionate, organic foaming agent such as carboxylic acid esters such as propionic acid ethyl ester, and the like can be used chemical blowing agents such as, for example, azo compounds. These other foaming agents can be used alone or in admixture of two or more. These other foaming agents can be added to the extent that the production, appearance and physical properties of the foam are not impaired.

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

  In the present invention, the styrene resin foam obtained by extrusion foaming contains, as a foaming agent, a) at least one saturated hydrocarbon having 3 to 5 carbon atoms. When the amount of the saturated hydrocarbon having 3 to 5 carbon atoms in the foaming agent remaining in the foam is less than the above range (2 to 6 parts by weight with respect to 100 parts by weight of the styrene resin), good heat insulation performance is obtained. There is a tendency to be difficult to be.

  The residual content of saturated hydrocarbons having 3 to 5 carbon atoms in the obtained styrenic resin foam varies depending on the type of saturated hydrocarbon compound, the density of the foam, etc., but generally in 100 parts by weight of the foam. On the other hand, it is preferably 2 to 6 parts by weight. More preferably, 2.5 to 6 parts by weight of propane, 2 to 6 parts by weight of n-butane and isobutane, and 2 to 6 parts by weight of n-pentane, isopentane and neopentane are used from the viewpoint of heat insulation performance and flame retardancy. preferable.

  In the present invention, at least one selected from d) halogen-based flame retardants and e) at least one selected from phosphorus-based flame retardants are allowed to coexist in the styrene resin foam. Thus, even when a highly combustible hydrocarbon is used as a foaming agent, it has a feature that a high degree of flame retardancy as defined in JIS A9511 can be achieved.

  Examples of the halogen-based flame retardant used in the present invention include, as brominated flame retardants, hexabromocyclododecane, tetrabromocyclooctane, dibromoneopentyl glycol, tribromoneopentyl alcohol, tris (2,3-dibromopropyl). ) Brominated aliphatic or alicyclic hydrocarbons such as isocyanurate, tetrabromoethane, hexabromobenzene, pentabromotoluene, ethylenebispentabromodiphenyl, decabromodiphenyl, decabromodiphenylethane, decabromodiphenyl ether, octabromo Brominated aromatic compounds such as diphenyl ether and 2,3-dibromopropylpentabromophenyl ether, tetrabromobisphenol A, tetrabromobisphenol A-bis (2,3-dibromo Propyl ether), tetrabromobisphenol A (2-bromoethyl ether), tetrabromobisphenol A diglycidyl ether, tetrabromobisphenol A bis (allyl ether), an adduct of tetrabromobisphenol A diglycidyl ether and tribromophenol, tetra Brominated bisphenols such as bromobisphenol S and tetrabromobisphenol S-bis (2,3-dibromopropyl ether) and derivatives thereof, tetrabromobisphenol A polycarbonate oligomer, addition of tetrabromobisphenol A diglycidyl ether and brominated bisphenol Brominated bisphenol derivatives oligomers such as epoxy oligomers, ethylene bistetrabromophthalimide, bis (2,4,6 Tribromophenoxy) ethane, tris (tribromophenoxy) triazine, brominated aromatic compounds such as brominated acrylic resins, ethylene bis-dibromo norbornane dicarboximide and the like. Examples of the chlorinated flame retardant include chlorinated aliphatic compounds such as chlorinated paraffin, chlorinated naphthalene, and perchloropentadecane, chlorinated aromatic compounds, and chlorinated alicyclic compounds. These halogen flame retardants can be used alone or in admixture of two or more. Of the halogen-based flame retardants, brominated flame retardants are preferable from the viewpoint of flame retardancy, and hexabromocyclododecane, tetrabromocyclooctane, tetrabromobisphenol A bis ( Allyl ether) is preferred. Content of a halogenated flame retardant is 0.1-6 weight part with respect to 100 weight part of styrene resin, Preferably it is 1-6 weight part. If the content of the halogen-based flame retardant is less than the above, the target flame retardancy of the present invention tends to be difficult to obtain, whereas if it exceeds the above range, the moldability during foam production may be impaired. is there.

  Examples of the phosphorus flame retardant used in the present invention include phosphate ester compounds, and the phosphate ester compounds include halogen-containing phosphate ester compounds and halogen-free phosphate ester compounds. Specific examples of the halogen-containing phosphate ester compounds include tris (halogenated alkyl) such as tris (2-chloroethyl) phosphate, tris (chloropropyl) phosphate, tris (dichloropropyl) phosphate, tris (tribromoneopentyl) phosphate, and the like. ) Halogenated phosphate compounds such as phosphates. Specific examples of the halogen-free phosphate ester compounds include trialkyl phosphates such as trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri (2-ethylhexyl) phosphate (the alkyl group preferably has 1 to 12 carbon atoms) , Trialkoxyalkyl phosphate such as tributoxyethyl phosphate (preferably alkoxyalkyl group having 2 to 12 carbon atoms), dimethyl phosphate, diethyl phosphate, dibutyl phosphate, diisodecyl phosphate, dialkyl such as di (2-ethylhexyl) phosphate Monoalkyl phosphates (as alkyl groups, preferably alkyl groups having 1 to 12 carbon atoms), monoisodecyl phosphate, etc. C1-C12 are preferred), aliphatic phosphate esters such as 2-acryloyloxyethyl acid phosphate, acyloxyalkyl phosphates such as 2-methacryloyloxyethyl acid phosphate, triphenyl phosphate, tricresyl phosphate , Trixyl phosphate, tris (isopropylphenyl) phosphate, tris (phenylphenyl) phosphate, trinaphthyl phosphate, cresyl diphenyl phosphate, xylyl diphenyl phosphate, di (isopropylphenyl) phenyl phosphate, etc. Group, which may be substituted with a phenyl group, diphenyl (2-ethylhexyl) phosphate, diphenyl (2-acrylic group). Aromatic phosphate esters such as diarylalkyl phosphates such as yloxyethyl) phosphate and diphenyl (2-methacryloyloxyethyl) phosphate, and diaryl acyloxyalkyl phosphates (aryl groups and alkyl groups may be substituted) Can be given. These phosphorus flame retardants can be used alone or in admixture of two or more. Among the phosphorus-based flame retardants, tris (tribromoneopentyl) phosphate and triphenyl phosphate are particularly preferable because of the large synergistic effect in combination with the halogen-based flame retardant.

  The phosphorous flame retardant content is higher than the flame retardancy of the halogen flame retardant alone, so that a higher flame retardancy and a synergistic effect of suppressing ignition and combustion of hydrocarbons that volatilize during combustion can be obtained. It is 0.1-3 weight part with respect to 100 weight part of styrenic resin, Preferably it is 0.3-3 weight part. When the content of the phosphorus-based flame retardant is less than the above range, a synergistic effect tends to be difficult to be obtained. On the other hand, when the content exceeds the above range, moldability during foam production may be impaired.

  In the present invention, at least one selected from halogen-based flame retardants and at least one selected from phosphorus-based flame retardants are used in an appropriate amount within the above-described range, so that the contribution mechanism to flame retardancy has not yet been determined. However, the radicals generated during combustion of the styrene resin foam are probably captured by halogen, and the non-combustible gas generated by decomposition, melting, etc. reduces the oxygen concentration around the combustion site, flame retardant coating or carbon foam coating. It is presumed that a synergistic effect of combustion inhibition such as formation of a flame retardant layer or a heat insulating layer is produced by the formation, and high flame retardancy tends to be easily obtained.

  That is, when a saturated hydrocarbon is used as the foaming agent, the residual foaming agent is released from the foam into the atmosphere during combustion of the foam, and the foaming agent burns, so that the foaming heat is generated by the combustion heat of the foaming agent. There is a tendency for surface melting to spread and spread. However, with respect to these tendencies, combustion of the residual foaming agent can be inhibited by using a halogen-based flame retardant and adding at least one compound selected from phosphorus-based flame retardants. Can be reduced or eliminated, and by using an appropriate amount, a foam molded article having excellent flame retardancy and molding stability can be obtained. .

  Furthermore, in this invention, at least 1 sort (s) chosen from a boric acid metal salt is used as a bubble diameter regulator.

  Examples of the metal borate used in the present invention include barium borate, magnesium borate, calcium borate, aluminum borate, zinc borate, strontium borate, zirconium borate, tin borate, and borax. . Among these, barium borate, magnesium borate, and calcium borate are preferable from the viewpoint of the effect of adjusting the bubble diameter and moldability. Particularly preferred is barium borate. Content of boric-acid metal salt is 0.1-6 weight part with respect to 100 weight part of styrenic resin, Preferably it is 0.5-6 weight part. When the content of the boric acid metal salt is less than the above range, the adjustment of the cell diameter, which is the object of the present invention, tends to be difficult to achieve. On the other hand, when the content exceeds the above range, the moldability at the time of foam production is impaired. There is.

  Furthermore, the addition of a boric acid metal salt can contribute to flame retardancy. Moreover, the compounding amount of the metal borate salt is usually 10 to 20 parts by weight or more depending on the type of the resin with respect to 100 parts by weight of the thermoplastic resin by combining with the halogen-based flame retardant. However, the effect of the present invention can be achieved with a minimum amount of about several parts by weight.

  Furthermore, in the present invention, in order to obtain higher flame retardancy, the flame retardancy is further improved by adding at least one nitrogen-containing compound selected from the group consisting of cyanuric acid, isocyanuric acid and derivatives thereof. To do.

  Specific examples of the nitrogen-containing compound include monoalkyl cyanurates such as cyanuric acid and methyl cyanurate, dialkyl cyanurates such as diethyl cyanurate, trialkyl cyanurates such as trimethyl cyanurate and triethyl cyanurate, phenyl cyanurate, and diphenyl. Dialkyl phenyl cyanurates such as cyanurate, triphenyl cyanurate, dimethylphenyl cyanurate, monoalkyl isocyanurates such as isocyanuric acid and methyl isocyanurate, dialkyl isocyanurates such as diethyl isocyanurate, trimethyl isocyanurate, triethyl isocyanurate, etc. Trialkyl isocyanurate, phenyl isocyanurate, diphenyl isocyanurate, triphenyl isocyanurate, Dialkylphenyl isocyanurates such as methylphenyl isocyanurate, mono (aminoalkyl) isocyanurates such as mono (2-aminoethyl) isocyanurate, di (aminoalkyl) isocyanurates such as di (2-aminoethyl) isocyanurate, tri Tri (aminoalkyl) isocyanurate such as (2-aminoethyl) isocyanurate, tri (hydroxymethyl) isocyanurate, tri (2-hydroxyethyl) isocyanurate, tri (2-hydroxypropyl) isocyanurate Bis (carboxyl) such as di (hydroxyalkyl) isocyanurate such as alkyl) isocyanurate, di (hydroxymethyl) isocyanurate, and bis (2-carboxyethyl) isocyanurate Kill) isocyanurate, 1,3,5-tris (2-carboxyethyl) isocyanurate and the like 1,3,5-tris (carboxyalkyl) isocyanurate, tris (2,3-epoxypropyl) isocyanurate and the like It is done. These nitrogen-containing compounds can be used alone or in combination. Of these, isocyanuric acid is preferred because it has a large synergistic effect in combination with a halogen-based flame retardant and a phosphorus-based flame retardant.

  The content of nitrogen-containing compounds is higher than that of the flame retardant combination of the halogen-based flame retardant and the phosphorus-based flame retardant, and has a synergistic effect of suppressing ignition and combustion of hydrocarbons that volatilize during combustion. Therefore, 0.1 to 5 parts by weight is preferable with respect to 100 parts by weight of the styrene resin, and more preferably 1 to 5 parts by weight. When the content of the nitrogen-containing compound is less than the above range, the synergistic effect tends to be difficult to be obtained. On the other hand, when the content exceeds the above range, moldability at the time of foam production may be impaired.

  Furthermore, in this invention, in order to obtain a higher heat insulation performance, a heat insulation performance improves further by adding a titanium oxide. Among these, titanium oxide surface-treated with a silicon-based compound such as silicon oxide is preferable. When surface treatment has not been applied, or when titanium oxide surface-treated with a silicon-based compound other than a zinc-based compound is used, thermal stability is likely to be affected by thermal history in mixed systems with halogenated flame retardants. In the case where it is intended to stably obtain a foam excellent in both heat insulation performance and flame retardancy as in the present invention, there may be a problem in flame retardancy. The content of titanium oxide is preferably 0.2 to 6 parts by weight, more preferably 0.5 to 6 parts by weight with respect to 100 parts by weight of the styrene resin. When the content of titanium oxide is out of the above range, the function as a heat-insulating agent tends not to appear remarkably.

  In the styrene resin foam of the present invention, the bubbles of the foam 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 formed in a sea island shape through a bubble film. It has a characteristic bubble structure in which the area ratio of bubbles having a bubble diameter of 0.25 mm or less occupying per foam cross-sectional area is 10 to 90%. The heat insulation performance of the foam having the large and small cell structure is excellent because the heat flow moving through the uniform cell structure in the conventional foam having the uniform cell structure is different from that in the foam having the large and small cell structure. It is presumed that it is divided by small bubbles having a fine bubble diameter of 0.25 mm or less present around large bubbles having a bubble diameter of 0.3 to 1 mm.

  In the present invention, at least one compound selected from bentonite, hectorite, and inorganic porous material is used to obtain the foam having the large and small cell structure. These compounds mainly act as an absorptive substance that absorbs the third component foaming agent (for example, water), and enables uniform dispersion of the third component in the styrene resin. In this invention, in addition to this absorptive substance, the said large and small bubble structure made into the objective of this invention can be easily obtained by using together the said borate metal salt as a bubble diameter regulator.

  Bentonite as used in the present invention is composed mainly of montmorillonite (a thin silicate layer having a thickness of about 1 nm, the surface of the plate-like crystal particles is negatively charged, and an exchangeable positive electrode such as sodium or calcium is interposed between the layers. This is a clay mineral that maintains neutrality in charge through ions and hydrates with the exchangeable cations between layers when water comes in contact with them, and swells between the layers. Quartz, α-Cristobalite, Opal It is a basic clay mineral containing accompanying minerals such as feldspar and mica.

  Examples of the bentonite used in the present invention include natural bentonite and purified bentonite. In addition, montmorillonite-modified products such as organic bentonite, anionic polymer-modified montmorillonite, silane-treated montmorillonite, and highly polar organic solvent composite montmorillonite are also included in the category.

  Examples of hectorite used in the present invention include natural hectorite and synthetic hectorite. In addition, modified products such as organic treatment, anionic polymer modification, and silane treatment are also included in the category.

  Examples of the inorganic porous material used in the present invention include silicon dioxide, silica gel, activated carbon, zeolite, and calcium silicate.

  As the absorbent material of the third component foaming agent, absorbent or absorption swellable clay such as saponite and swellable fluorine mica, organically treated products thereof, water-absorbing polymer compounds, and the like can also be used. These absorptive substances can also be used in combination with the bentonite, hectorite, and inorganic porous substance.

  The blending amount of at least one compound selected from bentonite, hectorite, and inorganic porous material is preferably 0.2 to 10 parts by weight, more preferably 1 to 5 parts by weight with respect to 100 parts by weight of the styrenic resin. is there. When the compounding amount of the compound is less than the above range, not only the target large / small cell structure tends to be hardly obtained, but also the absorption and / or adsorption amount of the third component blowing agent is insufficient, On the other hand, pores are generated due to non-dispersion of the third component such as water, and the molded product tends to be defective. On the other hand, when the amount is larger than the above range, gel non-dispersion occurs in the extruder, air bubbles become uneven, and the heat insulation performance of the foam deteriorates and tends to vary.

  When obtaining a foam having a large and small cell structure which is the object of the present invention, small cells having a cell diameter of 0.25 mm or less have an occupied area ratio of 10 to 90% per cross-sectional area of the foam. The occupied area ratio of the small bubbles is preferably 20 to 90%, more preferably 30 to 90%, and most preferably 35 to 90% per cross-sectional area of the foam. As described above, it is preferable that the small bubble occupation area ratio is large because the heat insulation performance is improved.

  In the present invention, conventionally known bubble diameter adjusting agents such as talc, wollastonite, kaolin, clay, etc. may be used. These conventional cell diameter regulators are preferably used in an amount of less than 3 parts by weight, more preferably 2.5 parts by weight or less, based on 100 parts by weight of the styrene resin. When the blending amount of the conventional bubble diameter adjusting agent is 3 parts by weight or more, there is a tendency to hinder the formation of the large and small cell structure which is the object of the present invention. There is a tendency to cause remarkable deterioration of sex.

  In the present invention, an inorganic compound such as silica, mica, zinc oxide, titanium oxide, calcium carbonate, sodium stearate, magnesium stearate, barium stearate, fluidity as long as the effect of the present invention is not inhibited as necessary. Processing aids such as paraffin, olefinic wax, stearylamide compounds, phenolic antioxidants, phosphorus stabilizers, light-resistant stabilizers such as benzotriazoles, hindered amines, other flame retardants, antistatic agents, pigments Additives such as coloring agents can be included.

In the present invention, a styrene-based resin foam obtained by heating and melting a styrene-based resin, adding a foaming agent, and extrusion-foaming the styrene-based resin, and as a foaming agent for 100 parts by weight of the styrene-based resin, a) 2 to 6 parts by weight of at least one saturated hydrocarbon having 3 to 5 carbon atoms, b) 1 to 7 parts by weight of at least one compound selected from the group consisting of methyl chloride, ethyl chloride and dimethyl ether, c ) 0.1 to 5 parts by weight of a third component foaming agent (excluding chlorofluorocarbon foaming agent), and as a flame retardant, d) at least one selected from halogenated flame retardants 0.1 to 6 E) at least one selected from 0.1 to 3 parts by weight selected from a phosphorus-based flame retardant, and f) at least one selected from metal borate as a cell diameter regulator 0.1 Contains ~ 6 parts by weight, foam density is 0~50kg / m is ^3, and the bubbles of the foam is composed of bubbles of primarily cell diameter 0.25mm or less of the bubble and the bubble diameter 0.3 to 1 mm, island-like these bubbles through the bubble membrane To obtain a foam structure having a cell structure in which the area ratio of bubbles having a bubble diameter of 0.25 mm or less per cross-sectional area of the foam is 10 to 90%. Without using an agent, it is possible to achieve both heat insulation and flame retardancy that meet the specifications of three types of extruded polystyrene foam heat insulating plates specified in JIS A9511. That is, the thermal insulation is 0.028 W / mK or less in terms of thermal conductivity, and the flame retardancy is measured in flammability as defined in JIS A9511. It is possible to obtain a styrene-based resin extruded foam that satisfies the condition that it does not burn beyond the combustion limit indicator line.

  Here, the three types of extruded polystyrene foam heat insulating plates specified in JIS A9511 mean the type of extruded polystyrene foam heat insulating plate 3a or 3b specified in JIS A9511. The standard of thermal conductivity is the same between the extruded polystyrene foam heat insulating plates 3a and 3b specified in JIS A9511. Furthermore, the standard of combustibility is the same between the extruded polystyrene foam heat insulating plates 3a and 3b specified in JIS A9511. From this point, when referring to the heat insulation property and flame retardancy of the extruded polystyrene foam heat insulating plate in the present invention, three types of extruded polystyrene foam heat insulating plates specified in JIS A9511 and simplified expressions are used.

  A preferred embodiment for obtaining a styrene resin extruded foam having both heat insulating properties and flame retardancy that meets the specifications of three kinds of extruded polystyrene foam heat insulating plates specified in JIS A9511 is as follows. Among the saturated hydrocarbons having 3 to 5 carbon atoms, n-butane and / or isobutane is preferably used as the blowing agent, and isobutane is particularly preferably used. As the flame retardant, any of the compounds shown in the present invention can be preferably used as the halogen-based flame retardant, but hexabromocyclododecane, tetrabromocyclooctane, and tetrabromobisphenol A bis (allyl ether) are particularly preferable. Further, any of the compounds shown in the present invention can be preferably used as the phosphorus-based flame retardant, but triphenyl phosphate and tris (tribromoneopentyl) phosphate are particularly preferable. In addition, as the cell diameter adjusting agent, any of the compounds shown in the present invention can be preferably used as the metal borate salt, but barium borate, magnesium borate, and calcium borate are more preferable because they are the most difficult. In order to obtain flammability, it is desirable to further use at least one compound selected from nitrogen-containing compounds. In order to obtain the best heat insulation, titanium oxide can be used, and it is particularly desirable to use titanium oxide surface-treated with a silicon compound in combination.

  The styrene resin foam of the present invention is (1) at least one compound selected from (1) halogenated flame retardant, phosphorus flame retardant, metal borate, bentonite, hectorite, and inorganic porous material in styrene resin, If necessary, at least one compound selected from nitrogen-containing compounds, titanium oxide, and other additives are mixed and then heat-melted; (2) halogen-based flame retardant, phosphorus after heat-melting the styrene resin -Based flame retardant, boric acid metal salt, bentonite, hectorite, at least one compound selected from inorganic porous materials, if necessary, at least one compound selected from nitrogen-containing compounds, titanium oxide, other additives (3) Halogen flame retardant, phosphorus flame retardant, metal borate, bentonite, hectorite, inorganic Preparing at least one compound selected from a porous substance, and, if necessary, at least one compound selected from nitrogen-containing compounds, titanium oxide, and other additives, and then heating and melting the composition; At least one selected from styrene-based resin, halogen-based flame retardant, phosphorus-based flame retardant, metal borate, bentonite, hectorite, and inorganic porous material by various methods such as supplying to an extruder again and heating and melting; And, if necessary, at least one compound selected from nitrogen-containing compounds, titanium oxide, and other additives are supplied to heating and melt-kneading means such as an extruder, and foamed under high pressure conditions at any stage. The agent is added to the styrenic resin to form a fluid gel, cooled to a temperature suitable for extrusion foaming, and the fluid gel is extruded and foamed into a low pressure region through a die to form a foam. It is produced by.

  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. Although the heating temperature should just be more than the temperature which the styrene resin to be used melt | dissolves, the temperature which suppresses the molecular degradation of resin by the influence of a flame retardant etc. as much as possible, for example, about 150-220 degreeC is preferable. The melt-kneading time varies depending on the amount of extrusion per unit time, the melt-kneading means and the like, and thus cannot be determined unconditionally. However, the time required for uniformly dispersing and mixing the styrenic 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 deterioration of the resin as much as possible, it is preferable to use a low shear type screw for the screw shape.

  Also, the foam molding method is not particularly limited. For example, the foam obtained by releasing the pressure from the slit die is used to form a large cross-sectional area using a molding die and a molding roll installed in close contact with or in contact with the slit die. A general method for forming a plate-like foam can be used.

The thickness of the foam of the present invention is not particularly limited and is appropriately selected depending on the application. 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 1 to 150 mm, preferably 10 to 100 mm. The density of the foam of the present invention is preferably 20 to 50 kg / m ³ in order to give light weight and excellent heat insulation, bending strength and compressive strength.

  Next, although the styrenic resin foam of this invention and its manufacturing method are demonstrated in detail based on an Example, this invention is not restrict | limited only to this Example. Unless otherwise specified, “parts” represents parts by weight and “%” represents% by weight.

  As the characteristics of the foams obtained in Examples 1 to 13 and Comparative Examples 1 to 4 shown below, the appearance, density, small bubble occupation area ratio, residual gas amount, thermal conductivity, and flammability are determined according to the following methods. Examined. Finally, comprehensive evaluation was made with “Excellent” being “Excellent”, “Good” being excellent, and “X” having some problem with the characteristics.

1) Appearance The appearance of the foam was visually inspected, and “◎” indicates that the appearance is extremely good, “◯” indicates that the appearance is good, and “×” indicates that the appearance is extremely poor such as voids or cracks.

2) Density (kg / m ³ )
The foam density was determined based on the following formula, and the unit was shown in terms of kg / m ³ .
Foam density (g / cm ³ ) = foam weight (g) / foam volume (cm ³ )

3) Small bubble occupation area ratio (%)
The occupied area ratio per cross-sectional area of the foam having a bubble diameter of 0.25 mm or less was determined as follows. Here, a bubble having a bubble diameter of 0.25 mm or less is a bubble having an equivalent circle diameter of 0.25 mm or less.
a) Magnify 30 times with a scanning electron microscope (manufactured by Hitachi, Ltd., product number: S-450) and photograph a longitudinal section of the foam.
b) An OHP sheet is placed on the photograph taken, 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 dimension larger than 0.25 mm) is black ink. Fill in and copy (primary processing).
c) The primary processed image is taken into the image processing apparatus (Pierce Co., Ltd., product number: PIAS-II), and the dark color portion and the light color portion, that is, the portion painted with black ink are identified.
d) Of the dark portion, a portion corresponding to the area of a circle having a diameter of 7.5 mm or less, that is, a portion having a long diameter in the thickness direction but only an area of a circle having a diameter of 7.5 mm or less. Is lightened to correct the dark portion.
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.
Small bubble occupation area ratio (%) = (1−area of dark color portion / area of entire image) × 100

4) Residual amount of gas (g / 100g)
By analyzing the foam after 14 days of production using a gas chromatograph (GC-14A, manufactured by Shimadzu Corporation), the amount of residual foaming agent (g) relative to 100 g of the foam was determined.

5) Thermal conductivity (W / mK)
It measured according to JIS A9511. The measurement was performed on a foam that had passed 30 days after production. Those having a thermal conductivity (0.028 W / mK or less) matched with the three types of extruded polystyrene foam heat insulating plates specified in JIS A9511 were designated as “OK”, and those other than that were designated as “NG”.

6) Combustibility A foam test (measurement method A) was conducted with 5 test pieces using 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 for a foam that had passed 14 days after production. The determination was made according to the following criteria.
Burning time ◎: All 5 flame extinguishing times are within 3 seconds. ○: Out of 5 flame extinguishing times, at least one exceeds 3 seconds, but the remaining 3 or more are within 3 seconds. Δ: Flame extinguishing time. Of the five, at least three of them exceed 3 seconds, but the remaining one or more are within 3 seconds. X: Combustion situation in which all 5 flame extinguishing times exceed 3 seconds. ◎: Burn within the combustion limit indicator line. Stops, no combustion of the foaming agent is observed. ○: Combustion stops within the combustion limit indicator line, and some combustion of the foaming agent is observed. Δ: Combustion exceeds the combustion limit indicator line, and the foaming agent burns. Is observed, but does not lead to complete burning.

Example 1
100 parts of polystyrene resin (manufactured by Kaneka Chemical Co., Ltd., trade name: KPS, melt index (MI): 3.1) as an additive, 0.5 part of talc and 0.3 part of calcium stearate, halogen 4.0 parts of hexabromocyclododecane (HBCD) as a flame retardant, 1.0 part of tris (tribromoneopentyl) phosphate (trade name: CR900, manufactured by Daihachi Chemical Co., Ltd.) as a phosphorus flame retardant, boric acid Dry blend of 1.0 part of barium (manufactured by Sakai Chemical Co., Ltd., trade name: BUSAN11), 0.5 part of synthetic hectorite and 0.3 part of silicon dioxide, and the resulting resin mixture having a diameter of 65 mm and a diameter A 90 mm piece was supplied to a two-stage extruder connected in series at a rate of about 80 kg / hr. The resin mixture supplied to the extruder having a diameter of 65 mm is heated to 200 ° C. to melt or plasticize and knead, and the resin temperature is cooled to 120 ° C. with an extruder having a diameter of 90 mm connected thereto. Extruded into the atmosphere from a rectangular cross-section die having a thickness direction of 2 mm and a width direction of 50 mm provided at the tip of the extruder, a rectangular parallelepiped extruded foam having a thickness of about 40 mm and a width of about 150 mm was obtained. At this time, as a blowing agent, 4.0 parts of isobutane, 4.0 parts of methyl chloride, and 0.8 parts of water are added to 100 parts of polystyrene resin from different lines in the vicinity of the tip of the 65 mm diameter extruder (bore diameter). The resin was press-fitted into the resin from the end connected to the end opposite to the base of the 90 mm extruder. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4 below, a foam having both high flame resistance and heat insulation performance was obtained.

Example 2
Extruded foam was obtained under the same conditions as in Example 1, except that 1.0 part of titanium oxide (titanium oxide surface-treated with a silicon compound, manufactured by Sakai Chemical Co., Ltd., trade name: R7E) was added. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Example 3
As a phosphorus flame retardant, use tris (1.0 parts of triphenyl phosphate (Ajinomoto Fine Techno Co., Ltd., trade name: Leophos TPP) instead of tribromoneopentyl phosphate, and add 1.0 part of titanium oxide. Except for the above, an extruded foam was obtained under the same conditions as in Example 1. The properties of the obtained foam are shown in Table 1. Compared with Comparative Examples 1 to 4, the flame retardant performance and the heat insulation performance are high. A compatible foam was obtained.

Example 4
An extruded foam was obtained under the same conditions as in Example 1 except that 0.5 part of triphenyl phosphate was added as a phosphorus-based flame retardant and 1.0 part of titanium oxide was added. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Example 5
As a phosphorus flame retardant, tris (0.5 parts of triphenyl phosphate is used instead of tribromoneopentyl phosphate, isocyanuric acid (trade name: ICA-P, manufactured by Shikoku Kasei Co., Ltd.) as a nitrogen-containing compound. Except that 0 part was added and 1.0 part of titanium oxide was added, an extruded foam was obtained under the same conditions as in Example 1. The properties of the obtained foam are shown in Table 1. Comparative Examples 1 to Compared to 4, a foam having both high flame retardancy and heat insulation performance was obtained.

Example 6
As a phosphorus flame retardant, tris (0.5 parts of triphenyl phosphate was used instead of tribromoneopentyl phosphate, the amount of barium borate was changed to 3.0 parts, and 1.0 part of titanium oxide was added. Except for the above, an extruded foam was obtained under the same conditions as in Example 1. The properties of the obtained foam are shown in Table 1. Compared with Comparative Examples 1 to 4, both high flame retardancy and heat insulation performance are achieved. A foam was obtained.

Example 7
An extruded foam was obtained under the same conditions as in Example 1 except that 2.5 parts of dimethyl ether was used instead of methyl chloride as the foaming agent. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Example 8
An extruded foam was obtained under the same conditions as in Example 1 except that the amount of isobutane was changed to 3.0 parts and 1.0 part of propane was added as a foaming agent. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Example 9
Extruded foams were obtained under the same conditions as in Example 1 except that 1.0 part of bentonite (product name: Bentolite 11 manufactured by Toyoshun Co., Ltd.) was used in place of synthetic hectorite. It was. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Example 10
Extrusion foaming under the same conditions as in Example 1 except that 2.0 parts of calcium borate (trade name: calcium borate, manufactured by Tomita Pharmaceutical Co., Ltd.) was used as the metal borate salt instead of barium borate. Got the body. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Example 11
Extrusion foaming under the same conditions as in Example 1 except that 2.0 parts of magnesium borate (trade name: magnesium borate, manufactured by Tomita Pharmaceutical Co., Ltd.) was used as the metal borate salt instead of barium borate. Got the body. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Example 12
Use 4.0 parts of tetrabromocyclooctane (manufactured by Albemarle Asano Co., Ltd., trade name: SAYTEX BC-48) instead of HBCD as the halogen flame retardant, and change the amount of barium borate to 2.0 parts Except that, an extruded foam was obtained under the same conditions as in Example 1. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Example 13
Use 4.0 parts of tetrabromobisphenol A bis (allyl ether) (trade name: 122K, manufactured by Tosoh Corporation) instead of HBCD as the halogen flame retardant, and adjust the amount of barium borate to 2.0 parts. Except for the change, an extruded foam was obtained under the same conditions as in Example 1. The properties of the obtained foam are shown in Table 1. As compared with Comparative Examples 1 to 4, a foam having both high flame resistance and heat insulation performance was obtained.

Comparative Example 1
Extruded foam under the same conditions as in Example 1 except that only 4.0 parts of HBCD was used as the flame retardant, no phosphorus flame retardant was used, and no metal borate was used as the cell diameter regulator. Got. The properties of the obtained foam are shown in Table 1. Compared with Example 1, the flame retardancy is inferior.

Comparative Example 2
As a foaming agent, the amount of isobutane was changed to 1.0 part, only 4.0 parts of HBCD was used as a flame retardant, no phosphorus flame retardant was used, and a metal borate was used as a cell diameter regulator. Extruded foam was obtained under the same conditions as in Example 1 except that there was no. The properties of the obtained foam are shown in Table 1. Compared with Example 1, the heat insulation is inferior.

Comparative Example 3
An extruded foam was obtained under the same conditions as in Example 1 except that the metal salt of borate was not used as the cell diameter adjusting agent and the amount of talc was changed to 3.0 parts. The properties of the obtained foam are shown in Table 1. Compared with Example 1, the small bubble occupation area ratio falls and heat insulation is inferior.

Comparative Example 4
An extruded foam was obtained under the same conditions as in Example 1 except that the metal salt of borate was not used as the cell diameter adjusting agent and the amount of talc was changed to 6.0 parts. The properties of the obtained foam are shown in Table 1. Compared with Example 1, the appearance is inferior, the small bubble occupation area ratio is lowered, and the heat insulation is inferior.

Claims (16)

A styrene-based resin foam obtained by heating and melting a styrene-based resin, adding a foaming agent, and extruding the styrene-based resin, and having 100 parts by weight of the styrene-based resin as a foaming agent, a) having 3 carbon atoms 2 to 6 parts by weight of at least one kind of saturated hydrocarbon which is ˜5, b) 1 to 7 parts by weight of at least one compound selected from the group consisting of methyl chloride, ethyl chloride and dimethyl ether, and c) the third component 0.1 to 5 parts by weight of a foaming agent (excluding a fluorocarbon foaming agent), and as a flame retardant, d) at least one selected from halogenated flame retardants 0.1 to 6 parts by weight; e) 0.1 to 3 parts by weight of at least one selected from phosphorus-based flame retardants, and 0.1 to 6 parts by weight of at least one selected from f) metal borate as a cell diameter regulator. Containing, foam density 20-50k A / m ^3, and the bubbles of the foam is composed of bubbles of primarily cell diameter 0.25mm or less of the bubble and the bubble diameter 0.3 to 1 mm, these bubbles dispersed in a sea-island shape through the bubble membrane An area ratio of bubbles having a bubble diameter of 0.25 mm or less per cross-sectional area of the foam is 10 to 90%. The styrenic resin foam according to claim 1, wherein the saturated hydrocarbon having 3 to 5 carbon atoms is at least one saturated hydrocarbon selected from the group consisting of propane, n-butane and i-butane. The third component foaming agent comprises at least one inorganic foaming agent selected from the group consisting of water, carbon dioxide and nitrogen, and / or one alcohol selected from methyl alcohol and ethyl alcohol. 3. A styrene resin extruded foam according to 1 or 2. The halogen-based flame retardant is at least one halogen-based flame retardant selected from the group consisting of hexabromocyclododecane, tetrabromocyclooctane, and tetrabromobisphenol A bis (allyl ether). The styrenic resin foam according to Item. The styrene resin foam according to any one of claims 1 to 4, wherein the phosphorus flame retardant is at least one phosphorus flame retardant selected from triphenyl phosphate and tris (tribromoneopentyl) phosphate. The styrenic resin foam according to any one of claims 1 to 5, wherein the metal borate salt comprises at least one selected from the group consisting of barium borate, magnesium borate, and calcium borate. The styrenic resin foam according to claim 6, wherein the metal borate salt is barium borate. 8. The composition according to claim 1, comprising 0.2 to 10 parts by weight of at least one compound selected from the group consisting of bentonite, hectorite, and inorganic porous material with respect to 100 parts by weight of the styrenic resin. The styrenic resin foam described. The styrene resin foam according to any one of claims 1 to 8, wherein the third component foaming agent is water. Furthermore, 0.1 to 5 parts by weight of at least one nitrogen-containing compound selected from the group consisting of cyanuric acid, isocyanuric acid and derivatives thereof is contained with respect to 100 parts by weight of styrene resin. Item 10. The styrenic resin foam according to any one of Items 1 to 9. Furthermore, the styrene resin foam of any one of Claims 1-10 which contains 0.2-6 parts of titanium oxide with respect to 100 weight part of styrene resins.   The styrene resin foam according to claim 11, wherein the titanium oxide is a titanium oxide surface-treated with a silicon compound. The styrene system according to any one of claims 1 to 12, which does not contain a freon-based foaming agent and has both heat insulation properties and flame retardancy, which conform to three types of extruded polystyrene foam heat insulating plates specified in JIS A9511. Resin foam. The styrenic resin foam according to claim 13, wherein the heat insulation property is 0.028 W / mK or less in terms of thermal conductivity. 15. The flame retardant according to claim 13 or 14, wherein in the measurement of flammability specified in JIS A9511, the flame is extinguished within 3 seconds, there is no residue, and the combustion does not exceed the combustion limit indicator line. Styrenic resin foam. A method for producing a styrene resin foam in which a styrene resin is heated and melted, a foaming agent is added, and this is extruded and foamed, with 100 parts by weight of a styrene resin as a foaming agent, a) having a carbon number 2 to 6 parts by weight of at least one saturated hydrocarbon that is 3 to 5; b) 1 to 7 parts by weight of at least one compound selected from the group consisting of methyl chloride, ethyl chloride, and dimethyl ether; and c) third. And 0.1 to 5 parts by weight of a component foaming agent (excluding chlorofluorocarbon foaming agents), and d) 0.1 to 6 parts by weight of at least one selected from halogenated flame retardants E) containing 0.1 to 3 parts by weight of at least one selected from phosphorus-based flame retardants, and f) at least one selected from metal borate 0.1 to 6% by weight as a cell diameter regulator Part is extruded and foamed, Foam density of 20 to 50 kg / m ^3, and the bubbles of the foam is composed of bubbles of primarily cell diameter 0.25mm or less of the bubble and the bubble diameter 0.3 to 1 mm, these bubbles bubbles film To obtain a styrene resin foam in which the area ratio of bubbles having a bubble diameter of 0.25 mm or less per unit area of the foam is 10 to 90%. Manufacturing method.