JP2015089921A - Method for producing polystyrene-based resin extruded foam plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an industrial advantageous method for producing a polystyrene-based resin extruded foam plate capable of stably obtaining a satisfactory foamed plate having excellent surface smoothness and high flame retardancy by improving production stability during extrusion foaming molding by improving kneadability and compatibility between a polystyrene-based resin virgin raw material and a specific flame retardant to improve dispersibility of the flame retardant.SOLUTION: There is provided a method for producing a polystyrene-based resin extruded foam plate by extrusion-foaming a foamable molten resin composition obtained by kneading a polystyrene-based resin composition and a physical foaming agent, where there is used a polystyrene-based resin composition which comprises a polystyrene-based resin (a), a brominated butadiene-styrene copolymer (b) and a polystyrene-based resin composition containing a styrene-based resin and a butadiene-styrene copolymer in a specific ratio.

Description

  The present invention relates to a method for producing a polystyrene-based resin extruded foam board, and more specifically, is a polystyrene-based resin extruded foam board having excellent flame retardancy and high heat insulation properties, and is used for heat insulation of building walls, floors, roofs, and the like. The present invention relates to a method for producing a polystyrene-based resin extruded foam plate that is suitably used for a material, a tatami core material, and the like and is mainly formed in a plate shape.

  Conventionally, an air conditioner is added to a polystyrene-based resin material, heated and kneaded by an extruder, and then a physical foaming agent is pressed into the extruder and further kneaded, and the molten mixture is changed from a high pressure range to a low pressure range (usually atmospheric) A thick polystyrene-based resin extruded foam plate (hereinafter also referred to as an extruded foam plate or a foamed plate) by molding into a plate shape with a shaping device connected to the die outlet of the extruder. It has been known.

In order to use the extruded foam board as a heat insulating material for construction, for example, it is required to satisfy the flammability standard of an extruded polystyrene foam heat insulating board described in JIS A 9511 (2006R). For this purpose, a flame retardant is added to the extruded foam plate, and hexabromocyclododecane (hereinafter referred to as HBCD) has been widely used as the flame retardant. HBCD is an excellent flame retardant that is versatile and can provide a flame retardant effect with a relatively small amount of addition.
However, there is a movement of regulation by the Chemical Substances Control Law and REACH for HBCD, and it is required to develop a flame retardant substitute extrusion foam board manufacturing technology that does not use HBCD flame retardant assuming that it is designated as a regulated substance. ing.

  On the other hand, chlorofluorocarbons (hereinafter referred to as CFC) such as dichlorodifluoromethane have been widely used as the foaming agent in the method for producing the extruded foam plate, but the relevance to the problem of ozone hole expansion. CFCs that are suspected of being refrained from being used, hydrogen atom-containing fluorinated fluorinated hydrocarbons (hereinafter referred to as HCFC) having a low ozone depletion potential, and hydrogen atom-containing fluorinated hydrocarbons having an ozone depletion potential of 0 (zero) HFC) has been used instead of CFC. Furthermore, from the viewpoint of global warming, saturated hydrocarbons such as isobutane and isopentane having an ozone depletion coefficient of 0 (zero) and a small global warming coefficient have been used instead of HCFC and HFC.

  However, since saturated hydrocarbons such as butane are flammable, in order to give sufficient flame retardancy to polystyrene-based resin extruded foam plates, compared to the case of using nonflammable foaming agents such as HFC. Many flame retardants had to be added. When a large amount of a flame retardant is added, a problem that stable productivity at the time of extrusion foaming is remarkably impaired or the physical properties of the obtained foamed plate are impaired newly arises.

In the above situation, studies have been made on polystyrene resin extruded foam plates using an excellent flame retardant other than HBCD. For example, a brominated butadiene-styrene copolymer type represented by Patent Document 1 has been proposed.
However, this brominated butadiene-styrene copolymer type flame retardant is inferior in thermal stability and has a problem in generating black spots (black foreign matters).

  In order to improve the thermal stability of such brominated butadiene-styrene copolymer type flame retardants, a method in which the flame retardant contains an alkyl phosphite and / or an epoxy compound has also been proposed ( For example, Patent Document 2).

  However, since the method of Patent Document 2 uses a brominated butadiene-styrene copolymer and a flame retardant obtained by simply dry blending other additives in a mixer, the thermal stability is still insufficient. There was room for improvement in the stable productivity at the time of extrusion foaming, such as surface irregularities occurring in the resulting foamed material and the appearance being lowered.

Special table 2009-516019 Special table 2012-512942 gazette

  The present invention was made to solve these problems, and by improving the dispersibility and kneadability of the flame retardant in the polystyrene resin, the extrusion stability was improved, and the surface smoothness was excellent. It is another object of the present invention to provide an industrially advantageous method for producing a polystyrene resin foam plate, which can stably obtain a foam plate having high flame retardancy.

According to this invention, the manufacturing method of the polystyrene-type resin extrusion foam board shown below is provided.
<1>
A method for producing a polystyrene resin extruded foam board by extrusion foaming a foamable resin melt obtained by kneading a polystyrene resin composition and a physical foaming agent,
The polystyrene resin composition comprises a polystyrene resin (a), a brominated butadiene-styrene copolymer (b), and a polystyrene resin composition (including a polystyrene resin and a butadiene-styrene copolymer). c) and
The blending amount of the butadiene-styrene copolymer in the polystyrene-based resin composition (c) is 0.1 to 50% by weight, and the blending amount of the brominated butadiene-styrene copolymer (b) is It is 0.5-20 weight part with respect to 100 weight part of this polystyrene resin (a), and the compounding quantity of this polystyrene resin composition (c) is 5 with respect to 100 weight part of this polystyrene resin (a). The manufacturing method of the polystyrene-type resin extrusion foam board characterized by being -150 weight part.
<2>
The polystyrene resin extruded foam according to <1>, wherein the polystyrene resin composition (c) is a melt-kneaded product containing a polystyrene resin, a butadiene-styrene copolymer, and a heat stabilizer. Body manufacturing method.
<3>
The heat stabilizer is one or more heat stabilizers selected from bisphenol type epoxy compounds, novolak type epoxy compounds, hindered phenol compounds, hindered amine compounds and phosphite compounds. The manufacturing method of the polystyrene-type resin extrusion foam board as described in said <2>.
<4>
Any one of <1> to <3>, wherein the butadiene-styrene copolymer in the polystyrene-based resin composition (c) includes a brominated butadiene-styrene copolymer. Manufacturing method of polystyrene-based resin extruded foam.
<5>
The polystyrene resin composition (c) obtained by heating and melting polystyrene resin extruded foam waste and / or pulverized foamed foam containing a brominated butadiene-styrene copolymer. It is a resin composition, The manufacturing method of the polystyrene-type resin extrusion foamed board in any one of said <1> to <4> characterized by the above-mentioned.
<6>
The method for producing a polystyrene-based resin extruded foam plate according to any one of <2> to <5>, wherein the polystyrene-based resin composition (c) is pelletized.
<7>
Any one of <2> to <6>, wherein 95% by weight or more of the brominated butadiene-styrene copolymer (b) passes through a sieve screen having an opening of 500 μm. The manufacturing method of the polystyrene-type resin extrusion foam board as described in 2.

  In the present invention, a polystyrene resin (a), a brominated butadiene-styrene copolymer (b), a polystyrene resin composition (c) containing a polystyrene resin and a butadiene-styrene copolymer, And the brominated butadiene-styrene copolymer (b), wherein the blended amount of the butadiene-styrene copolymer in the polystyrene-based resin composition (c) is 0.1 to 50% by weight. The blending amount of the polystyrene resin (a) is 0.5 to 20 parts by weight, and the blending amount of the polystyrene resin composition (c) is 100 parts by weight of the polystyrene resin (a). 5 to 150 parts by weight with respect to the polystyrene resin composition having a specific configuration is extruded and foamed, and thus the dispersibility and mixing of the flame retardant composition (b) into the polystyrene resin (a) Sex is improved, the improved extrusion stability, the foam plate having excellent appearance without surface irregularities can be produced stably. Furthermore, since the flame retardant is uniformly and sufficiently dispersed by the polystyrene-based resin composition (c), an extruded foam board having improved flame retardancy can be obtained.

The method of producing a polystyrene resin extruded foam plate by extrusion foaming a foamable resin melt containing a polystyrene resin composition and a physical foaming agent of the present invention,
The polystyrene resin composition satisfies the following requirements (i) and (ii).
(I) polystyrene resin (a), brominated butadiene-styrene copolymer (hereinafter also referred to as brominated butadiene-styrene copolymer) (b), polystyrene resin and butadiene-styrene copolymer Containing a polystyrene-based resin composition (c) containing a coalescence.
(Ii) The blending amount of the butadiene-styrene copolymer (b) which is 0.1 to 50% by weight of the butadiene-styrene copolymer in the polystyrene resin composition (c) and is brominated Is 0.5 to 20 parts by weight with respect to 100 parts by weight of the polystyrene resin (a), and the blending amount of the polystyrene resin composition (c) is 5 to 150 parts with respect to 100 parts by weight of the polystyrene resin (a). It must be part by weight.

According to the study by the present inventors, this melt-kneaded product of brominated butadiene-styrene copolymer has high viscosity and low fluidity, and has left a problem in kneadability with a polystyrene resin as a base resin. . That is, when manufacturing for a long time as industrial production, it discovered that extrusion stability was lacking and an unevenness | corrugation may generate | occur | produce in a part of a foamed board.
Therefore, as a result of further investigation, a polystyrene resin composition containing a low concentration of butadiene-styrene copolymer in a system in which polystyrene resin (a) and brominated butadiene-styrene copolymer (b) coexist. In the polystyrene-based resin composition formed by blending the product (c), an extruded foam plate having excellent surface smoothness and good color tone is stable even when extruded and foamed continuously for a long time. It was found that it can be manufactured.

  The reason why the above-mentioned effect is manifested is not clear, but the polystyrene-based resin composition (c) functions as a compatibilizer for the polystyrene-based resin (a) and the brominated butadiene-styrene copolymer (b). The dispersibility and kneadability of the brominated butadiene-styrene copolymer (b) in the polystyrene resin (a) are considered to be improved. Furthermore, it has been found that by adding a polystyrene resin composition (c) containing a butadiene-styrene copolymer at a low concentration, an extruded foam plate having improved flame retardancy can be obtained simultaneously with the above-described action. The above-mentioned effect is considered to be manifested from the fact that the brominated butadiene-styrene copolymer (b) is uniformly and sufficiently dispersed in the extruded foam plate. The present invention has been made based on these findings.

  Hereinafter, the polystyrene resin composition used in the method for producing a polystyrene resin extruded foam plate of the present invention will be described.

(Essential component of polystyrene resin composition)
The polystyrene-based resin composition includes at least a polystyrene-based resin (a), a polystyrene-based resin composition (c) containing a brominated butadiene-styrene copolymer (b), a polystyrene-based resin, and a butadiene-styrene copolymer. including. The blending amount of the butadiene-styrene copolymer in the polystyrene resin composition (c) is 0.1 to 50% by weight.

(Polystyrene resin (a))
Examples of the polystyrene resin (a) include styrene-acrylic acid copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-methacrylic acid copolymer having polystyrene or styrene as a main component. Polymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-maleic anhydride copolymer, styrene-polyphenylene ether copolymer, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer Examples thereof include a polymer, a styrene-methylstyrene copolymer, a styrene-dimethylstyrene copolymer, a styrene-ethylstyrene copolymer, and a styrene-diethylstyrene copolymer. The styrene unit component content in the styrenic copolymer is preferably 50 mol% or more, particularly preferably 80 mol% or more.

  As said polystyrene-type resin, what mixed the other polymer may be sufficient in the range in which the objective of this invention and an effect are achieved. Other polymers include polyester resins and polyethylene resins (one or a mixture of two or more selected from the group consisting of ethylene homopolymers and ethylene copolymers having an ethylene unit component content of 50 mol% or more). , Polypropylene resins (one or a mixture of two or more selected from the group of propylene homopolymers and propylene copolymers having a propylene unit component content of 50 mol% or more), polyphenylene ether resins, styrene-ethylene copolymers Polymers and the like, and these other polymers are less than 50% by weight in the polystyrene resin, preferably 30% by weight or less, more preferably 10% by weight or less. Can be mixed according to the purpose.

Moreover, as said polystyrene-type resin, it is preferable to use the thing whose melt viscosity (200 degreeC and the conditions of a shear rate of 100 sec- ¹ ) is about 500-2500 Pa.s from a foamable or moldable viewpoint, Preferably it is 600-2000 Pa.s, More preferably, it is 700-1500 Pa.s.

(Brominated butadiene-styrene copolymer (b))

In the present invention, the brominated butadiene-styrene copolymer (b) used as a flame retardant is a weight average molecular weight of about 1.0 × 10 ^{3 to} 2.0 × 10 ^{5 in} terms of polybutadiene, preferably A butadiene copolymer of 2.0 × 10 ^{3 to} 1.0 × 10 ⁵ , more preferably 5.0 × 10 ^{3 to} 1.0 × 10 ⁵ , and still more preferably 5.0 × 10 ^{4 to} 1.0 × 10 ⁵ . Produced by brominating the polymer.

  The butadiene-styrene copolymer in the brominated butadiene-styrene copolymer (b) includes a block copolymer of butadiene and one or more styrene monomers (diblock, multiblock such as triblock). ), A random copolymer or a graft copolymer, and a block copolymer of a styrene polymer block and a brominated polybutadiene block from the viewpoint of compatibility with the polystyrene resin (a). preferable.

Examples of butadiene include a butadiene homopolymer, a block copolymer of butadiene containing 10% by weight or more of a butadiene component and one or more other monomers, a random copolymer, or a graft copolymer. Is done. The ratio of 1,4-butadiene units to 1,2-butadiene units in the butadiene polymer is such that the 1,2-butadiene units are 50% or more, more than 70%, especially 85% of the butadiene units in the butadiene polymer. The above is preferable.
Examples of the styrene monomer include styrene, 2-bromostyrene, 4-bromostyrene, 2-chlorostyrene, 4-chlorostyrene, 2-methoxystyrene, 4-methoxystyrene, 2-nitrostyrene, and 4-nitro. Examples thereof include styrene, 2-methylstyrene, 4-methylstyrene, 2,4-dimethylstyrene, α-methylstyrene, and among these, styrene, 4-methylstyrene, α-methylstyrene or a mixture thereof is preferable. More preferably, it is styrene.

  From the viewpoint of imparting flame retardancy, the bromine content in the brominated butadiene-styrene copolymer is preferably 50% by weight or more, more preferably 60% by weight or more. The bromine content can be determined based on JIS K7392: 2009.

Considering dispersibility in the polystyrene resin (a), the weight average molecular weight of the brominated butadiene-styrene copolymer is preferably 1.0 × 10 ^{5 to} 2.0 × in terms of polystyrene. is 10 approximately ^5, the 200 ° C., a melt viscosity at 100 sec ^-1 is about 4000~8000Pa · s.

  In the present invention, a polystyrene-brominated polybutadiene block copolymer, which is a typical brominated butadiene-styrene copolymer, can be represented by the following general formula.

(In the formula, X, Y and Z are positive integers.)

Such a polystyrene-brominated polybutadiene block copolymer is produced, for example, by brominating a polystyrene-polybutadiene block copolymer.
Examples of the polystyrene-brominated polybutadiene copolymer preferably used in the present invention include commercially available products such as Emerald 3000 from Chemtura and FR122P from ICL-IP.

  The brominated butadiene-styrene copolymer (b) is disclosed in detail in, for example, Patent Documents 1 and 2.

  Further, 95% by weight or more of the brominated butadiene-styrene copolymer (b) is preferably passed through a sieve screen having an opening of 500 μm in order to improve the problems such as the black spots. .

  In the present invention, the brominated butadiene-styrene copolymer exhibits an excellent flame retardancy imparting effect. However, since the brominated butadiene-styrene copolymer is inferior in thermal stability in the molten state, bromine is likely to be liberated from the polymer depending on conditions such as heat history during the molding process. There is a possibility that the effect of imparting flame retardancy may be reduced and the thermoplastic resin may be decomposed. In addition, when a carbon-carbon unsaturated bond is formed in the polymer due to liberation of the bromine, the polymer itself or polystyrene resin may be colored, or bromination may occur due to crosslinking of the unsaturated bond. There is a possibility that the butadiene-styrene copolymer that has been formed gels.

  When the majority of the brominated butadiene-styrene copolymer (b) used as a flame retardant has a small particle size that passes through a sieve screen having an opening of 500 μm, the thermal stabilizer is It has also been found that it can effectively act on brominated butadiene-based polymers and suppress the generation of black spots.

  From the viewpoint of suppressing the generation of black spots, the proportion of the brominated butadiene polymer having a large particle size is preferably as small as possible, and the proportion passing through a sieve net having an opening of 500 μm has a particle size of 97% by weight or more. More preferably, it is 99 weight% or more, More preferably, it is 100 weight%.

As a method for obtaining a brominated butadiene polymer having a particle size of 95% by weight or more passing through a sieve screen having an opening of 500 μm, for example, a brominated butadiene polymer described later is used as a raw material, and this is pulverized and crushed For example, a method of reducing the particle size by performing a process, a method of classifying using a sieve net, or the like.
In the present invention, the opening means a nominal opening based on JIS Z8801-1: 2006.

(Heat stabilizer)
Since the butadiene-styrene copolymer (b) brominated from the above is inferior in thermal stability, it is preferable to add a thermal stabilizer. Examples of the heat stabilizer for the brominated butadiene-styrene copolymer include one or more heat stabilizers selected from an epoxy compound, a phenol compound, a hindered amine compound, and a phosphite compound. In addition, it is preferable that the compounding quantity of the said heat stabilizer is 5-40 weight part with respect to 100 weight part of brominated butadiene-styrene copolymers (b).

  The epoxy resin compound is preferably a novolak type or a bisphenol type. As the bisphenol type epoxy compound, a brominated bisphenol A type epoxy compound, that is, a so-called brominated epoxy compound is particularly preferable. Examples of the bisphenol type epoxy compound and the novolak type epoxy compound include F2200HM manufactured by ICL-IP, EPICLON series manufactured by DIC, Araldite ECN1280 manufactured by HUNTUMAN, and the like.

Examples of the phenol compound include 2,6-di-t-butyl-p-cresol, triethylene glycol bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], tetrakis -[Methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, 2,2-methylenebis (4-methyl-6-t-butylphenol), 1,6-hexanediol- Bis [3- (3,5-di-tert-butyl-4-droxyphenyl) propionate], pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and the like Can be mentioned.
You may use these individually or in combination of 2 or more types. Among these, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] is preferable from the viewpoint of extrusion stability and flame retardancy.

Examples of the hindered amine compound include 4-hydroxy-2,2,6,6-tetramethylpiperidine, 4-hydroxy-1,2,2,6,6-pentamethylpiperidine, or 4-hydroxy-1- Octyloxy-2,2,6,6-tetramethylpiperidine aliphatic or aromatic carboxylic acid ester, bis (1,2,2,6,6-pentamethyl-4-piperidinyl) -2- (3,5- Di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonate, bis (2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis (1,2,2,6,6) -Pentamethyl-4-piperidinyl) sebacate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, tetrakis (2,2,6,6-tetramethyl-4 Piperidinyl) -1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidinyl) -1,2,3,4-butanetetracarboxylate and the like. It is done.
You may use these individually or in combination of 2 or more types. Among these, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, or bis (from the point of extrusion stability and flame retardancy) 2,2,6,6-tetramethyl-4-piperidinyl) sebacate is preferred.

  Examples of the phosphite compound include tris (2,4-di-t-butylphenyl) phosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, and bis (2,6 -Di-t-butyl-4-methylphenyl) pentaerythritol-diphosphite, distearyl pentaerythritol diphosphite, tetra (tridecyl) -4,4'-butylidene-bis (2-t-butyl-5-methylphenyl) Diphosphite, bis [2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl ester phosphorous acid, bis (nonylphenyl) pentaerythritol diphosphite, mono (dinonylphenyl) mono-p- Nonylphenyl phosphite, tris (monononylphenyl) phosphite, tetraalkyl (C = 12-16) -4,4′-isopropylidene- (bisphenyl) diphosphite, hexatridecyl-1,1,3-tris (3-tert-butyl-6-methyl-4oxyphenyl) -3 -Methylpropane triphosphite, diphenylisodecyl phosphite, tridecyl phosphite, tristearyl phosphite, hydrogenated bisphenol A pentaerythritol phosphite polymer and the like. You may use these individually or in combination of 2 or more types. Among these, from the viewpoint of extrusion stability, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite or bis (2,6-di-t-butyl-4-methylphenyl) penta Erythritol diphosphite is preferred.

  In addition, as said heat stabilizer, it is preferable to use together the compound selected from a bisphenol-type epoxy compound and / or a novolak-type epoxy compound, and a hindered phenol type compound, a hindered amine type compound, and a phosphite type compound. In the above case, the total amount of the bisphenol type epoxy compound and / or the novolak type epoxy compound is preferably 5 to 20 parts by weight with respect to 100 parts by weight of the brominated butadiene-styrene copolymer. On the other hand, the total amount of compounds selected from hindered phenol compounds, hindered amine compounds, and phosphite compounds is 0.2-20 with respect to 100 parts by weight of the brominated butadiene-styrene copolymer (b). A part by weight is preferred.

  In the present invention, other stabilizers such as metal soap, organotin compound, lead compound, hydrotalcite, polyhydric alcohol, β-ketone, adipic acid ester and sulfur compound can be used in combination with the stabilizer. .

In the present invention, the brominated butadiene-styrene copolymer (b) is directly added. However, the brominated butadiene-styrene copolymer (b) has a very high viscosity with respect to the polystyrene resin. In addition, the brominated butadiene-styrene copolymer (b) may have a problem in dispersibility in the polystyrene resin (a), and the extrusion stability may be lowered. This decrease in extrusion stability appears particularly when a thick foam plate is obtained.
In order to eliminate such problems, in the present invention, as described above, in order to improve the dispersibility, a polystyrene resin composition (c) containing 0.1 to 50% by weight of a butadiene-styrene copolymer is used. Use.

(Polystyrene resin composition (c))
That is, in the present invention, a polystyrene resin composition (c) containing a polystyrene resin as a base resin and 0.1 to 50% by weight of a butadiene-styrene copolymer is converted into a polystyrene resin (a) and bromine. And mixed with the butadiene-styrene copolymer (b).

  Examples of the butadiene-styrene copolymer contained in the polystyrene resin composition (c) include block copolymers of butadiene and one or more styrene monomers (multiblock such as diblock and triblock). A styrene polymer block and bromine from the viewpoint of compatibility between the polystyrene resin (a) and the brominated butadiene-styrene copolymer (b). A block copolymer with a modified polybutadiene block is preferred.

  Examples of butadiene include a butadiene homopolymer, a block copolymer of butadiene containing 10% by weight or more of a butadiene component and one or more other monomers, a random copolymer, or a graft copolymer. Is done. The ratio of 1,4-butadiene units to 1,2-butadiene units in the butadiene polymer is such that the 1,2-butadiene units are 50% or more, more than 70%, especially 85% of the butadiene units in the butadiene polymer. The above is preferable.

  Examples of the styrene monomer include styrene, 2-bromostyrene, 4-bromostyrene, 2-chlorostyrene, 4-chlorostyrene, 2-methoxystyrene, 4-methoxystyrene, 2-nitrostyrene, and 4-nitro. Examples thereof include styrene, 2-methylstyrene, 4-methylstyrene, 2,4-dimethylstyrene, α-methylstyrene, and among these, styrene, 4-methylstyrene, α-methylstyrene or a mixture thereof is preferable. More preferably, it is styrene.

  In addition, the said butadiene-styrene copolymer contained in a polystyrene-type resin composition (c) may be the same as the above-mentioned brominated butadiene-styrene copolymer (b).

  The polystyrene resin composition (c) is considered to act as a compatibilizer between the polystyrene resin (a) and the brominated butadiene-styrene copolymer (b). The polystyrene resin (a) And the brominated butadiene-styrene copolymer (b) are improved in kneadability, so that the extrusion stability is improved, and even when a thick foam plate such as an extruded foam heat insulating plate is used as a production target Thus, it is possible to stably obtain a thick foam plate having no unevenness and excellent surface smoothness.

  The blending amount of the butadiene-styrene copolymer in the polystyrene-based resin composition (c) is 0.1 to 25% by weight, further 0.1 to 10% by weight, further 0.2 to 8% by weight, and particularly preferably 0.8. 5 to 5 weight% is preferable. If the concentration is too low, the effect of improving the extrusion stability cannot be obtained. On the other hand, if the concentration is too high, the dispersibility of the flame retardant may be reduced. From the said viewpoint, More preferably, it is 0.2 to 8 weight%, More preferably, it is 0.5 to 6 weight%.

  Examples of the polystyrene resin composition (c) containing 0.1 to 50% by weight of a butadiene-styrene copolymer include those obtained by previously melt-kneading a butadiene-styrene copolymer and a polystyrene resin. In the kneaded product, the butadiene-styrene copolymer is preferably uniformly dispersed in the polystyrene resin. In addition, a brominated butadiene-styrene copolymer can be selected as the butadiene-styrene copolymer. It is preferable when obtaining the polystyrene-type resin composition (c) by which generation | occurrence | production of yellowing was suppressed.

  As the polystyrene resin composition (c), polystyrene resin extruded foam waste containing a brominated butadiene-styrene copolymer and / or pulverized product of the foam board, that is, brominated Milling material, scrap, and / or polystyrene-based extruded foam plate containing brominated butadiene-styrene copolymer generated during the production of polystyrene-based extruded foam plate containing butadiene-styrene copolymer What was cut, crushed and pulverized can be used.

  In addition, it is preferable that the said polystyrene-type resin composition (c) is extruded from an extruder from the meterability, the ease of handling, etc., and is cut and pelletized.

(Mixing ratio of essential constituents of polystyrene resin composition)
The polystyrene resin (a), the brominated butadiene-styrene copolymer (b), and the polystyrene resin composition (c) are desirably mixed in the following composition.

The blended amount of the brominated butadiene-styrene copolymer (b) is 0.5 to 20 parts by weight, preferably 1 to 15 parts by weight, based on 100 parts by weight of the polystyrene resin (a). Preferably it is 1-10 weight part.
If the blended amount of the brominated butadiene-styrene copolymer (b) is too large, extrusion foam molding may become unstable. On the other hand, if the blended amount of the brominated butadiene-styrene copolymer (b) is too small, it may be insufficient to obtain the desired flame retardancy.

  Further, the blending amount of the polystyrene resin composition (c) is 5 to 150 parts by weight, preferably 10 to 140 parts by weight, more preferably 15 to 130 parts by weight with respect to 100 parts by weight of the polystyrene resin (a). Parts, more preferably 20 to 110 parts by weight. When there is too much this composition (c), there exists a possibility that stability at the time of extrusion foaming may fall. On the other hand, if the amount is too small, the dispersibility of the flame retardant may be insufficient.

  The blending ratio (c / b) between (c) and (b) is 2 to 2 from the viewpoint of kneadability between the polystyrene resin (a) and the brominated butadiene-styrene copolymer (b). 50 is preferable and 3-40 is more preferable.

The polystyrene foam (a) has a weight average molecular weight of 200,000 to 450,000, and the polystyrene resin composition (c) has a weight average molecular weight of 200,000 to 400,000. It is preferable from the viewpoint of the effect of improving the mechanical properties of the plate.
The weight average molecular weight used in the present invention is a value obtained by dissolving 10 mg of a sample in 10 ml of tetrahydrofuran (THF), measuring by gel permeation chromatography (GPC) analysis, and calibrating with standard polystyrene.

  Furthermore, the ratio (Mwc / Mwa) of the weight average molecular weight (Mwc) of the polystyrene resin composition (c) to the weight average molecular weight (Mwa) of the polystyrene resin (a) is 0.5 to 1.1. Is preferable, and 0.7 to 1 is more preferable. In particular, when the brominated butadiene-styrene copolymer (b) is used as a flame retardant as in the present invention, the resin (a), the polymer (b) and the composition (c) are kneaded in the extrusion foaming step. Sometimes thermal degradation of the polystyrene resin is suppressed.

  Moreover, it is preferable that the melt viscosity of the said polystyrene-type resin composition (c) is 500-2500 Pa.s. When the melt viscosity is within the above range, the kneadability with other resins constituting the base resin becomes better. Furthermore, the ratio (ηc / ηa) of the melt viscosity (ηc) of the polystyrene resin composition (c) to the melt viscosity (ηa) of the polystyrene resin (a) is preferably 0.8-2. It is more preferable that it is 0.9-1.5 from the same viewpoint.

  In the present invention, the flame retardant composed of the brominated butadiene-styrene copolymer (b) may be used by mixing with other flame retardant within a range that does not hinder the object and effect of the present invention. it can. Other flame retardants include, for example, tetrabromobisphenol-A-bis (2,3-dibromo-2-methylpropyl ether), tetrabromobisphenol-S-bis (2,3-dibromo-2-methylpropyl ether), An organic compound having a 2,3-dibromo-2-methylpropyl group represented by tetrabromobisphenol-F-bis (2,3-dibromo-2-methylpropyl ether)), tetrabromobisphenol-A-bis (2 , 3-dibromopropyl ether), tetrabromobisphenol-S-bis (2,3-dibromopropyl ether), tetrabromobisphenol-F-bis (2,3-dibromopropyl ether), tris (2,3-dibromopropyl) ) Isocyanurate and tris (2,3-dibromopropyl) Organic compounds having a 2,3-dibromopropyl group typified by annulate, mono (2,3,4-tribromobutyl) isocyanurate, di (2,3,4-tribromobutyl) isocyanurate, tris (2 , 3,4-tribromobutyl) isocyanurate, brominated isocyanurate, cresyl di 2,6-xylenyl phosphate, antimony trioxide, antimony pentoxide, ammonium sulfate, zinc stannate, cyanuric acid, pentabromo Typical examples include nitrogen-containing cyclic compounds such as toluene, isocyanuric acid, triallyl isocyanurate, melamine cyanurate, melamine, melam, melem, silicone compounds, inorganic compounds such as boron oxide, zinc borate, zinc sulfide, and triphenyl phosphate. Phosphoric ester, red phosphorus, polyphosphorus Ammonium, phosphazene, phosphorus-based compounds such as hypophosphorous acid salts and the like. These compounds can be used alone or in admixture of two or more.

In this invention, the improvement effect of an oxygen index | exponent can be further heightened by mix | blending at least 1 sort (s) of adjuvant chosen from diphenylalkane, diphenylalkene, and polyalkylbenzene with a flame retardant in an extrusion foaming board. The auxiliary is preferably added in an amount of 0.5 to 20 parts by weight, more preferably 1 to 15 parts by weight, based on 100 parts by weight of the flame retardant.
Specific examples of the diphenylenyl alkane include 2,3-dimethyl-2,3-diphenylbutane, 2,3-diethyl-2,3-diphenylbutane, and 3,4-dimethyl-3,4-diphenylhexane. 3,4-diethyl-3,4-diphenylhexane. Specific examples of diphenylalkene include 2,4-diphenyl-4-methyl-1-pentene, 2,4-diphenyl-4-ethyl-1-pentene, and polyalkylenebenzene. Examples include poly-1,4-diisopropylbenzene.

  In the production method of the present invention, in addition to the flame retardant, a cell regulator can be added to the base resin in order to adjust the average cell diameter of the extruded foam plate. Examples of the air conditioner include inorganic substances such as talc, kaolin, mica, silica, calcium carbonate, barium sulfate, titanium oxide, clay, aluminum oxide, bentonite, and diatomaceous earth. Further, in the present invention, two or more kinds of the air bubble adjusting agents can be used in combination. Among the various bubble regulators, talc is preferably used because it is easy to adjust the bubble diameter of the foamed plate obtained and to easily reduce the bubble diameter. Talc having a 50% particle size (permeation centrifugal sedimentation method) of 0.5 to 75 μm is preferred.

  The addition amount of the cell regulator is 0.01 to 100 parts by weight with respect to a total weight of 100 parts by weight of the polystyrene resin (a), the brominated butadiene-styrene copolymer (b), and the polystyrene resin composition (c). It is preferable to add 5 parts by weight and further 0.1 to 4 parts by weight.

  In the production method of the present invention, in addition to the above-mentioned air conditioner and flame retardant, the heat insulating properties of graphite, hydrotalcite, carbon black, aluminum powder, titanium oxide, etc. are improved within the range not hindering the object and effect of the present invention. Various additives such as a colorant, a colorant, a filler and a lubricant can be appropriately added. In addition, it is preferable to add various additives, such as the said bubble regulator, as a masterbatch which uses thermoplastic resins, such as a polystyrene-type resin, as a base material.

(Foaming agent)
In the foaming agent used in the present invention, the saturated hydrocarbon (X) having 3 to 5 carbon atoms and the other foaming agent (Y) shown below can be used alone or in combination, and particularly described in the background art. From the viewpoint, it is more preferable to use a mixed foaming agent containing a saturated hydrocarbon (X) having 3 to 5 carbon atoms and another foaming agent (Y) shown below.

Examples of the saturated hydrocarbon (X) having 3 to 5 carbon atoms include propane, n-butane, i-butane, n-pentane, i-pentane, neopentane, and cyclopentane.
Said saturated hydrocarbon (X) can be used individually or in mixture of 2 or more types.
Among the saturated hydrocarbons (X), propane, n-butane, i-butane or a mixture thereof is preferable from the viewpoint of easily obtaining a foamed plate having a high expansion ratio. Moreover, n-butane, i-butane or a mixture thereof is preferable from the viewpoint of the heat insulating performance of the foamed plate, and i-butane is particularly preferable.

As other foaming agents (Y), other organic physical foaming agents and inorganic physical foaming agents can be used.
Examples of the organic physical foaming agent include ethers such as dimethyl ether, diethyl ether, ethyl methyl ether, di-n-butyl ether, diisopropyl ether, methanol, ethanol, propyl alcohol, i-propyl alcohol, butyl alcohol, i- Examples include alcohols such as butyl alcohol and t-butyl alcohol, formic acid esters such as methyl formate, ethyl formate, propyl formate, and butyl formate, and alkyl chlorides such as methyl chloride and ethyl chloride. In addition, trans-1,3,3,3-tetrafluoropropene, cis-1,3,3,3-tetrafluoropropene, 1,1,1,2 having a low ozone depletion coefficient and a low global warming potential Fluorinated unsaturated hydrocarbons such as tetrafluoropropene can also be used.
Examples of the inorganic physical foaming agent include water, carbon dioxide, nitrogen and the like.
Said other foaming agent (Y) can be used individually or in mixture of 2 or more types.

  Among the other foaming agents (Y), in combination with the foaming agent (X), methyl chloride, ethyl chloride, dimethyl ether, diethyl ether, ethyl from the viewpoints of foam plate moldability, high expansion ratio, etc. Methyl ether, methanol, ethanol, water and carbon dioxide are preferred.

  In the mixed foaming agent, the blending ratio of the saturated hydrocarbon (X) is 10 to 80 mol%, and the blending ratio of the other foaming agent (Y) is 90 to 20 mol% [however, the foaming agent (X) and The total amount with the foaming agent (Y) is preferably 100 mol%]. By using a mixed foaming agent with a blending ratio within this range, it becomes possible to produce an extruded foam plate having a high expansion ratio safely and stably, and an extruded foam plate excellent in heat insulation and flame retardancy. Is preferable in manufacturing. From this viewpoint, saturated hydrocarbon (X) 30 to 70 mol% and other blowing agent (Y) 70 to 30 mol% [however, the total amount of blowing agent (X) and blowing agent (Y) is 100 mol%. And a mixed foaming agent containing

  The addition amount of the foaming agent in the present invention should be 0.5 to 2.5 mol / kg in a total weight of 1 kg of the polystyrene resin (a) and the polystyrene resin composition (c). Is preferable, and 0.8 to 2.0 mol / kg is more preferable.

The apparent density of the polystyrene-based resin extruded foam plate obtained by the present invention is generally 20 to 60 kg / m ³ , preferably 22 to 50 kg / m ³ .

  The lower limit of the thickness of the polystyrene-based resin extruded foam plate is preferably 10 mm, more preferably 20 mm, and even more preferably 40 mm. In particular, when the thickness of the foamed plate is increased, the extrusion stability tends to be lowered, and the production method of the present invention is useful. Moreover, the upper limit is preferably 150 mm, more preferably 140 mm, and still more preferably 130 mm. The width of the extruded foam plate is preferably 450 mm to 1500 mm.

  Further, the average cell diameter in the thickness direction of the extruded foam plate is preferably 0.75 mm or less, more preferably 0.5 mm or less, and further preferably 0.3 mm or less in order to obtain a foam plate having higher heat insulating properties. preferable. The lower limit of the average bubble diameter is approximately 0.03 mm, preferably 0.06 mm.

  Next, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the examples.

  In order to obtain the extruded foam plates of Examples and Comparative Examples, the following apparatuses and materials were used.

[Extruding equipment]
A first extruder having an inner diameter of 65 mm and a second extruder having an inner diameter of 90 mm are connected in series, a physical foaming agent injection port is provided near the end of the first extruder, and a gap of 1 mm × width of 110 mm is provided at the outlet of the second extruder. The manufacturing apparatus which connected the flat die | dye provided with the resin discharge port (die lip) whose cross section is a rectangle was used.
A shaping device (guider) composed of a pair of upper and lower polytetrafluoroethylene resin plates was attached to the resin outlet of the flat die so that the upper and lower resin plates were parallel to each other.

[material]
(Polystyrene resin (a))
PS1: weight average molecular weight 27 × 10 ⁴ , melt viscosity 950 Pa · S (200 ° C., shear rate 100 sec ⁻¹ ), Tg 100 ° C., MFR 6.5 g / 10 min

(Brominated butadiene-styrene copolymer (b1))
b1: ICL-IP Co., Ltd., styrene-brominated butadiene block copolymer, trade name: FR122P, volume average particle size; D50 = 50 μm, opening ratio of 500 μm is 100% by weight, melt viscosity 4500 Pa · S (200 ° C., shear rate 100 sec ⁻¹ ).

(Brominated butadiene-styrene copolymer (b2, b3))
b2: Chemtura, styrene-brominated butadiene block copolymer, trade name: pulverized product of Emerald 3000, volume average particle size; D50 = 200 μm, D90 = 490 μm, ratio under mesh screen of mesh size 500 μm is 95% by weight , Melt viscosity 5300 Pa · S (200 ° C., shear rate 100 sec ⁻¹ ).
b3: manufactured by Chemtura, styrene-brominated butadiene block copolymer, trade name: Emerald 3000, volume average particle size; D50 = 500 μm, D90 = 1000 μm, mesh ratio of 75% by weight under sieve screen, melt viscosity 5300 Pa · S (200 ° C., shear rate 100 sec ⁻¹ ).

  The volume average particle diameters in the above b1, b2, and b3 are values measured by Nikkiso Co., Ltd. Microtrac MT-3300EX2. Further, the ratio of the above b1, b2 and b3 under the sieve screen having a mesh size of 500 μm is a value obtained by classifying using a sieve screen having a mesh size of 500 μm as defined in JIS Z8801-1: 2006, and determining the ratio under the mesh screen. It is.

(Polystyrene resin composition (c1))
c1: Using an extruder with an inner diameter of 50 mm, the raw materials shown in Table 1 were put into the extruder, melt-kneaded at a resin temperature of 185 ° C., extruded under conditions of 15 kg / hour of discharge, pelletized, and pelletized polystyrene A resin composition (c1) was obtained.

(Polystyrene resin composition (c2))
A first extruder having an inner diameter of 65 mm and a second extruder having an inner diameter of 90 mm are connected in series, a physical foaming agent injection port is provided near the end of the first extruder, and a gap of 1 mm × width of 110 mm is provided at the outlet of the second extruder. The manufacturing apparatus which connected the flat die | dye provided with the resin discharge port (die lip) whose cross section is a rectangle was used. Further, a flat die resin outlet was provided with a shaping device (guider) composed of a pair of upper and lower polytetrafluoroethylene resin plates so that the upper and lower resin plates were parallel to each other.
c2: As shown in Table 2, the PS1, b1, bubble regulator and heat stabilizer were heated to 200 ° C. with a first extruder and melt-kneaded, and the physical foaming agent was supplied from the physical foaming agent inlet. The molten resin composition further melted and kneaded in the first extruder is supplied to the subsequent second extruder, and the resin temperature is expressed as the foaming temperature (in Table 2, the foaming temperature. The temperature of the foamable molten resin composition measured at the position of the joint portion of the resin is adjusted to a temperature of 2) and then extruded into a guider arranged in parallel with a gap of 50 mm from the die lip at a discharge rate of 70 kg / hour and foamed. While being passed through the guider, it was molded (shaped) into a plate shape to produce a polystyrene resin extruded foam plate. Next, the extruded foamed plate was pulverized by a pulverizer, then supplied to a single-screw extruder having an inner diameter of 90 mm and L / D = 50, kneaded at a maximum temperature of 220 ° C., and the molten resin was discharged in an amount of 250 kg. / Extruded and pelletized to obtain a pellet-shaped polystyrene resin composition (c2).

(Polystyrene resin composition (c3))
c3: As shown in Table 2, polystyrene (c3) was produced in the same manner as c2, except that the flame retardant (b1) was changed to the flame retardant (b2).

(Polystyrene resin composition (c4))
c4: As shown in Table 2, polystyrene (c4) was produced in the same manner as c2, except that the flame retardant (b1) was changed to the flame retardant (b3).
(Bubble preparation agent)
Talc: Made by Matsumura Sangyo Co., Ltd., Talc, trade name; High filler # 12

(Heat stabilizer)
EPICLON: manufactured by DIC, novolac type epoxy resin, trade name: EPICLON N680
Irganox: manufactured by BASF, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], trade name: Irganox 1010
PEP: manufactured by ADEKA, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-diphosphite, trade name: PEP36

Example 1
A first extruder having an inner diameter of 65 mm and a second extruder having an inner diameter of 90 mm are connected in series, a physical foaming agent injection port is provided near the end of the first extruder, and a gap of 1 mm × width of 110 mm is provided at the outlet of the second extruder. The manufacturing apparatus which connected the flat die | dye provided with the resin discharge port (die lip) whose cross section is a rectangle was used. Further, a flat die resin outlet was provided with a shaping device (guider) composed of a pair of upper and lower polytetrafluoroethylene resin plates so that the upper and lower resin plates were parallel to each other.

  As shown in Table 3, the PS1, b1 and c1, bubble regulator and heat stabilizer were melted and kneaded with a first extruder up to 200 ° C., and the physical foaming agent was supplied from the physical foaming agent inlet. The molten resin composition further melt-kneaded in the first extruder is supplied to the subsequent second extruder to adjust the resin temperature to the foaming temperature (represented as the resin temperature in Table 3), and then the discharge amount is 70 kg. It was extruded from a die lip into a guider arranged in parallel with a gap of 50 mm / hour, and passed through the guider while being foamed to form (shape) a plate, thereby producing a polystyrene resin extruded foam plate.

(Examples 2 and 3)
In Example 1, the polystyrene-type resin extrusion foam board was obtained like Example 1 except having changed the compounding quantity of the polystyrene-type resin composition (c1) into the value shown in Table 3. FIG.

Example 4
A polystyrene resin extruded foam plate was obtained in the same manner as in Example 3 except that the polystyrene resin composition (c1) was changed to a recycled polystyrene resin composition (c2). In addition, ratio (MWc / Mwa) of the weight average molecular weight (Mwa) of the polystyrene resin (a) and the weight average molecular weight (Mwc) of the polystyrene resin composition (c) is 0.96, and the melt viscosity ratio. (Ηc / ηa) was 0.96.

(Example 5)
Except that the flame retardant was changed from (b1) to (b2) and the polystyrene resin composition (c2) was changed to a recycled polystyrene resin composition (c3), a polystyrene resin extruded foam plate was obtained in the same manner as in Example 4. Obtained. The ratio (MWc / Mwa) of the weight average molecular weight (Mwa) of the polystyrene resin (a) and the weight average molecular weight (Mwc) of the polystyrene resin composition (c) is 1.0, and the melt viscosity ratio (Ηc / ηa) was 1.

(Example 6)
Except that the flame retardant was changed from (b2) to (b3) and the polystyrene resin melt (c3) was changed to the polystyrene resin melt (c4), a polystyrene resin extruded foam plate was obtained in the same manner as in Example 5. Obtained. The ratio (MWc / Mwa) of the weight average molecular weight (Mwa) of the polystyrene resin (a) and the weight average molecular weight (Mwc) of the polystyrene resin composition (c) is 1.0, and the melt viscosity ratio (Ηc / ηa) was 1. The obtained extruded foamed plate was dotted with black particles in the cross section of the foamed plate, although the heat insulating performance was not affected.

(Comparative Example 1)
A polystyrene resin extruded foam plate was obtained in the same manner as in Example 1 except that the polystyrene resin composition (c1) was not added.

  Extrusion stability in Examples 1-6 and Comparative Example 1, and apparent density, thickness, closed cell ratio, appearance, color tone, bubble diameter, thermal conductivity, flammability and The molecular weight is shown in Table 3.

The measurement method and evaluation method of various physical properties of the extruded foam plate shown in Table 3 are as follows.

(Extrusion stability)
A: An extruded foam board having no surface irregularities and good appearance can be obtained stably for a long time.
(Triangle | delta): When it drive | operates for a long time, discharge pressure will fluctuate and it will become an extrusion foam board in which surface unevenness was formed in a part.
×: Product cannot be obtained

(Apparent density)
It is an apparent density measured based on JIS K7222 (2005).

(thickness)
In the width direction of the extruded foam plate, thicknesses at five points were measured at equal intervals, and the arithmetic average value of these measured values was taken as the thickness (mm) of the extruded foam plate.

(Closed cell rate)
The closed cell ratio of the extruded foam plate was determined as follows. First, the extrusion foamed board was divided into 5 equal parts in the width direction, and cut samples (total 5 pieces) having no molded skin were cut out in the size of 25 mm × 25 mm × 20 mm from the vicinity of the center. Next, according to the procedure C of ASTM-D2856-70, the true volume Vx of each cut sample is measured, the closed cell ratio S (%) is calculated by the following formula (1), and the arithmetic average value of these calculated values is calculated. The closed cell ratio of the extruded foam plate was used. In addition, Toshiba Beckman Co., Ltd. air comparison type hydrometer 930 type | mold was used as a measuring apparatus.

S (%) = (Vx−W / ρ) × 100 / (Va−W / ρ) (1)
However, Vx: the true volume (cm ³ ) of the cut sample obtained by measurement with the above air comparison hydrometer (the volume of the resin composition constituting the cut sample of the extruded foam plate and the closed cell portion in the cut sample (This corresponds to the sum of the total volume of bubbles.)
Va: Apparent volume of the cut sample calculated from the outer dimensions of the cut sample used for measurement (cm ³ )
W: Total weight of cut sample used for measurement (g)
ρ: density of the resin composition constituting the extruded foam plate (g / cm ³ )

(appearance)
The smoothness of the product surface was evaluated visually.
○: smooth surface without irregularities Δ: surface irregularities occur during continuous production for a long time

(Bubble diameter)
Draw a line segment over the entire thickness in the thickness direction at the center and both ends of the vertical cross section in the width direction of the extruded foam plate (vertical cross section perpendicular to the extrusion direction of the extruded foam plate). The average diameter of the bubbles existing on each line segment (the length of the line segment / the number of bubbles intersecting the line segment) is obtained from the number of bubbles intersecting the line segment, and the arithmetic operation of the obtained average diameters at three locations The average value was taken as the bubble diameter.

(Thermal conductivity)
The thermal conductivity was measured by the following method based on the accelerated test described in ISO 11561.
A test piece having no molded skin of 200 mm × 200 mm × 10 mm was cut out from the central portion of the extruded foam plate immediately after production, and the test piece was stored in an atmosphere of 23 ° C. and humidity 50%. Ten days after production, using the test piece, based on the heat flow method described in JIS A1412-2: 1999 (one specimen, symmetrical configuration method, high temperature side 38 ° C., low temperature side 8 ° C., average temperature 23 ° C.) The thermal conductivity was measured.

(Combustion quality)
Immediately after production, the extruded foam plate was transferred to a room with an air temperature of 23 ° C. and a relative humidity of 50%. After leaving in that room for 4 weeks, five test pieces were randomly cut from the extruded foam plate (N = 5), and JIS Combustibility was measured based on 5.13.1 “Measurement method A” of A9511 (2006R), and the flame retardancy of the extruded foam plate was evaluated by the average burning time (seconds) of five test pieces.

(Weight average molecular weight)
The measurement was performed by gel permeation chromatography analysis.
This is a value obtained by dissolving 10 mg of a resin sample in 10 ml of tetrahydrofuran (THF), measuring by a gel permeation chromatography (GPC) analysis method, and calibrating with standard polystyrene.
Details of the GPC analysis conditions are as follows.
Equipment: GPC high performance liquid chromatograph column manufactured by GL Sciences Inc .: Showa Denko Co., Ltd., trade name ShodexGPC KF-806, KF-805, KF-803 are connected in series in this order, and column temperature used : 40 ° C
Solvent: THF
Flow rate: 1.0 mL / min Concentration: 0.15 w / v%
Injection volume: 0.2ml
Detector: UV-visible detector manufactured by GL Sciences Inc., trade name UV702 type (measurement wavelength 254 nm)
Molecular weight range of calibration curve used for calculation of molecular weight distribution: 1.2 × 10 ^{7 to} 5.2 × 10 ³

(Melt viscosity)
The melt viscosity in the table is a value obtained by measuring with a Capillograph Model 1D manufactured by Toyo Seiki Seisakusho. For details of the measurement, a capillary with a hole diameter of 1.0 mm and a length of 10 mm is attached to the tip of a cylinder with an inner diameter of 9.55 mm (effective length of 250 mm), and the cylinder and capillary are heated to 200 ° C. and measured in the cylinder. A sample (resin pellet) was filled. After filling, the cylinder was filled with a piston and melted by preheating for 4 minutes. During the preheating, the piston was temporarily pushed down to sufficiently remove bubbles from the molten measurement sample. Further, the filling amount of the measurement sample was set to a sufficient amount that could secure 15 cc or more of the measurement sample after removing the bubbles. After completion of the preheating, the measurement sample in the cylinder was extruded with a piston so that the shear rate of the capillary part was 100 s ^−1, and the melt viscosity at that time was measured. The melt viscosity was measured after the conditions of 200 ° C. and 100 s ⁻¹ were adopted and the extrusion load was stabilized.

Claims (7)

A method for producing a polystyrene resin extruded foam board by extrusion foaming a foamable resin melt obtained by kneading a polystyrene resin composition and a physical foaming agent,
The polystyrene resin composition comprises a polystyrene resin (a), a brominated butadiene-styrene copolymer (b), and a polystyrene resin composition (including a polystyrene resin and a butadiene-styrene copolymer). c) and
The blending amount of the butadiene-styrene copolymer in the polystyrene-based resin composition (c) is 0.1 to 50% by weight, and the blending amount of the brominated butadiene-styrene copolymer (b) is It is 0.5-20 weight part with respect to 100 weight part of this polystyrene resin (a), and the compounding quantity of this polystyrene resin composition (c) is 5 with respect to 100 weight part of this polystyrene resin (a). The manufacturing method of the polystyrene-type resin extrusion foam board characterized by being -150 weight part.   The polystyrene resin extruded foam according to claim 1, wherein the polystyrene resin composition (c) is a melt-kneaded product containing a polystyrene resin, a butadiene-styrene copolymer, and a heat stabilizer. Manufacturing method.   The heat stabilizer is one or more heat stabilizers selected from bisphenol type epoxy compounds, novolak type epoxy compounds, hindered phenol compounds, hindered amine compounds and phosphite compounds. The manufacturing method of the polystyrene-type resin extrusion foamed board of Claim 2.   The butadiene-styrene copolymer in the polystyrene-based resin composition (c) contains a brominated butadiene-styrene copolymer, according to any one of claims 1 to 3. A method for producing a polystyrene resin extruded foam.   The polystyrene resin composition (c) obtained by heating and melting polystyrene resin extruded foam waste and / or pulverized foamed foam containing a brominated butadiene-styrene copolymer. It is a resin composition, The manufacturing method of the polystyrene-type resin extrusion foam board in any one of Claims 1-4 characterized by the above-mentioned.   The method for producing a polystyrene-based resin extruded foam plate according to any one of claims 1 to 5, wherein the polystyrene-based resin composition (c) is pelletized.   7. The composition according to claim 2, wherein 95% by weight or more of the brominated butadiene-styrene copolymer (b) passes through a sieve screen having an opening of 500 μm. The manufacturing method of the polystyrene-type resin extrusion foamed board of description.