JP2003064231A - Weatherable impact-resistant styrene-based resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition excellent in weatherability and impact resistance using a specific styrene-based resin. SOLUTION: This styrene-based resin composition contains (A) 95-5 pts.wt. of a styrene-based resin having as a comonomer at least one of an acrylic acid alkyl ester monomer and a methacrylic acid alkyl ester monomer and (B) 5-95 pts.wt. of a multicomponent copolymer obtained by graft polymerizing at least one or more monomers selected from the group consisting of a methacrylic acid alkyl ester, an aromatic vinyl and an unsaturated nitrile to an acrylic rubbery polymer composed mainly of an acrylic acid alkyl ester monomer wherein the sum of (A) and (B) components is 100 pts.wt.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a styrene resin composition having excellent weather resistance and impact resistance. Specifically, a styrene resin containing at least one of an acrylic acid alkyl ester monomer and a methacrylic acid alkyl ester monomer as a copolymerization component, an acrylic rubber-like polymer, a methacrylic acid alkyl ester, an aromatic vinyl, and The present invention relates to a styrene-based resin composition having excellent weather resistance and impact resistance, which is composed of a multi-component polymer grafted with a monomer selected from the group consisting of unsaturated nitriles.

[0002]

2. Description of the Related Art Polystyrene (PS) resin, a typical styrene resin, acrylonitrile-styrene (AS
) Resins are widely used in packaging materials and sundries.
However, since these resins are brittle, they can be used only in limited applications. Therefore, the impact resistance of these resins has also been improved. The impact-resistant polystyrene (HIPS) and acrylonitrile-butadiene-styrene (ABS) resin, which have improved impact resistance, are also widely used in household appliances, office automation equipment, automobile materials and the like. However, the reinforcing rubber used to improve the impact resistance is polybutadiene, which is a conjugated diene rubber, and has poor weather resistance. That is, the double bond is oxidized by the influence of light, and the molded product changes color (yellowing),
In addition, there is a problem that mechanical strength is also reduced.

In order to overcome this drawback and enable the use of styrene resins having improved impact resistance outdoors, AS
In the case of the styrene-based resin, the AS resin is reinforced with a styrene-based resin reinforced with a non-conjugated diene rubber, specifically, an ethylene-propylene-non-conjugated diene copolymer rubber (EPDM) grafted with AS. Acrylonitrile-
EPDM-styrene (AES) resin or AS
There is an acrylonitrile-acrylic rubber-styrene (AAS) resin in which AS is reinforced with an acrylic rubber grafted with (generally also containing a conjugated diene component). However, although the AES resin or AAS resin has improved weather resistance as compared with the ABS resin, the AES resin has a rubber component EPDM containing a double bond in the molecule, or AAS resin Acrylic rubber, which is a rubber component, contains a conjugated diene component, or even if it does not contain a conjugated diene component, the AS resin itself has a limit in weather resistance. There is a problem that the surface is discolored and at the same time the mechanical strength is reduced. On the other hand, as the AS-based styrene-based resin containing acrylonitrile-styrene as a main component, a material called weather-resistant / impact-resistant resin such as AES resin or AAS resin has been put on the market as described above. With respect to the PS-based styrene-based resin, PS itself is inferior in weather resistance to AS, and therefore, at present, a material excellent in weather resistance and impact resistance has not been put on the market.

Acrylic resins are known as resins having excellent weather resistance. This acrylic resin is also brittle, and therefore impact-resistant acrylic resin having improved impact resistance is also on the market. However, this impact-resistant acrylic resin does not exhibit such high impact resistance even if it is referred to as an impact-resistant resin. Under such circumstances, there is a demand for a resin having weather resistance similar to that of an acrylic resin, excellent impact resistance, and capable of being supplied at a relatively low cost.

[0005]

In view of the above situation, the present invention provides a styrene resin composition which is excellent in weather resistance and impact resistance and can be supplied at a relatively low cost because it is based on a general-purpose resin. It is intended to be provided.

[0006]

Means for Solving the Problems As a result of intensive studies aimed at achieving the above object, the present inventors have found that a specific styrene resin, specifically, an alkyl acrylate monomer and / or Or a methacrylic acid alkyl ester monomer, preferably based on a styrene-based resin having an acrylic acid alkyl ester monomer as a copolymerization component, and a methacrylic acid alkyl ester, an aromatic vinyl in an acrylic rubber as an impact modifier. By using a multi-component polymer grafted with a monomer selected from the group consisting of and unsaturated nitrile, it has been found that it can be a styrene-based resin having excellent weather resistance, and excellent impact resistance,
The present invention has been completed.

That is, in the present invention, 95 to 5 parts by weight of a styrenic resin (A) containing at least one of an acrylic acid alkyl ester monomer and a methacrylic acid alkyl ester monomer as a copolymerization component, (B) Acrylic rubber polymer mainly composed of acrylic acid alkyl ester monomer,
Containing at least 5 to 95 parts by weight of a multi-component polymer obtained by graft-polymerizing at least one monomer selected from the group consisting of methacrylic acid alkyl ester, aromatic vinyl, and unsaturated nitrile, (A) The present invention relates to a styrene resin composition in which the total amount of the component and the component (B) is 100 parts by weight.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. First, the styrene resin that is the component (A) of the styrene resin composition of the present invention will be described. The styrene resin is a copolymer composed of an aromatic vinyl monomer component and at least one copolymerization component of an acrylic acid alkyl ester monomer and a methacrylic acid alkyl ester monomer component. By co-polymerizing an acrylic acid alkyl ester monomer and / or a methacrylic acid alkyl ester monomer with an aromatic vinyl monomer, the weather resistance is dramatically improved as compared with a homopolymer of an aromatic vinyl monomer. Will be good. Especially, discoloration (yellowing) is reduced. Here, as the aromatic vinyl monomer, in addition to styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4
-Dimethylstyrene, ethylstyrene, p-tert
-Nuclear alkyl-substituted styrene such as butyl styrene, α-
Examples thereof include α-alkyl-substituted styrenes such as methylstyrene and α-methyl-p-methylstyrene.
These aromatic vinyl monomers may be used alone or in combination of two or more.

The alkyl acrylate monomer and the methacrylic acid alkyl ester monomer preferably have an alkyl group having 2 to 12 carbon atoms. Further, the alkyl group may be linear or branched. Examples of the alkyl acrylate include, for example, methyl acrylate, ethyl acrylate, n-butyl acrylate, and acrylic acid i.
-Butyl, 2-ethylhexyl acrylate, pentyl acrylate, hexyl acrylate, n-octyl acrylate, cyclohexyl acrylate and the like can be mentioned. Examples of the alkyl methacrylate may include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate and the like.

The styrene resin which is the component (A) of the styrene resin composition of the present invention has the acrylic acid alkyl ester monomer and / or the methacrylic acid alkyl ester monomer as a copolymerization component as described above. Although it is a copolymer,
As a copolymerization component, acrylic acid alkyl ester has better weather resistance than methacrylic acid alkyl ester,
That is, the discoloration (yellowing) is small, which is more preferable. Usually, the main component of the acrylic resin having the best weather resistance is methyl methacrylate, but the styrene resin copolymerized with an alkyl acrylate ester is compared to the styrene resin copolymerized with an alkyl methacrylate ester. The reason why the weather resistance is excellent is not clear. However, the styrene resin is expected to discolor (yellowing) due to the removal of hydrogen in the main chain due to oxidative deterioration and the formation of conjugated double bonds. The presence of the body suppresses the formation of conjugated double bonds due to the hydrogen abstraction of the styrene monomer chain, in other words, the radicals that are probably generated are continuous by abstracting the hydrogen at the α-position of the alkyl acrylate. It is presumed that the formation of conjugated double bonds is prevented.

The styrenic resin which is the component (A) of the styrenic resin composition of the present invention comprises, as a copolymerization component, an acrylic acid alkyl ester monomer and / or a methacrylic acid alkyl ester monomer, as well as acrylonitrile and methacrylic acid. It may contain an unsaturated nitrile monomer such as ronitrile. The AS-based styrene-based resin containing the unsaturated nitrile monomer is excellent in weather resistance, particularly discoloration, as compared with the PS-based styrene-based resin composed of only the aromatic vinyl monomer.
However, it is not always sufficient. AS styrenic resin and acrylic acid alkyl ester monomer and /
Alternatively, the weather resistance is remarkably improved by copolymerizing a methacrylic acid alkyl ester monomer, preferably an acrylic acid alkyl ester monomer.

The styrene resin which is the component (A) of the styrene resin composition of the present invention is, as described above, an aromatic vinyl monomer or an aromatic vinyl monomer and an unsaturated nitrile monomer. Further, the copolymer mainly comprises an acrylic acid alkyl ester monomer and / or a methacrylic acid alkyl ester monomer, but other monomer components may be contained in addition to these monomers. Other monomer components include, for example, maleic acid, itaconic acid, ethyl maleic acid, methyl itaconic acid, anhydride monomers of unsaturated carboxylic acids such as chloromaleic acid, maleimide, N-methylmaleimide, N- Examples thereof include maleimide-based monomers such as phenylmaleimide, unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and cinnamic acid.

Examples of typical preferable copolymers of the styrene resin which is the component (A) of the styrene resin composition of the present invention include, for example, styrene / methyl acrylate, styrene / ethyl acrylate, styrene / Acrylic acid n-
Butyl, styrene / acrylonitrile / methyl acrylate, styrene / acrylonitrile / ethyl acrylate,
Examples thereof include styrene / acrylonitrile / n-butyl acrylate. Among these, styrene / n-butyl acrylate and styrene / acrylonitrile / n-butyl acrylate are particularly preferable because they have the effects of improving the fluidity of the styrene resin composition of the present invention and improving the processability. These can be obtained by known lump, suspension, emulsion or solution polymerization methods.

The amount of the acrylic acid alkyl ester monomer and / or the methacrylic acid alkyl ester monomer in the styrene resin as the component (A) of the styrene resin composition of the present invention is 1 to 45 parts by weight, The amount is preferably 2 to 30 parts by weight, more preferably 3 to 20 parts by weight. If the amount of the acrylic acid alkyl ester monomer and / or the methacrylic acid alkyl ester monomer is less than 1 part by weight, the weather resistance is poor, which is not preferable. If it exceeds 45 parts by weight, the properties of the styrene resin are impaired, which is not preferable.

The component (A) comprises an AS-based styrene resin, that is, an aromatic vinyl monomer, an unsaturated nitrile monomer, an acrylic acid alkyl ester monomer and / or a methacrylic acid alkyl ester monomer. In the case of the copolymer as the main component, the amount of unsaturated nitrile monomer in the styrene resin is 1 to 45 parts by weight, preferably 5 to 40 parts by weight, more preferably 6 to 35 parts by weight. When the amount is less than 1 part by weight, it is not preferable because the characteristics such as chemical resistance are inferior when it is used as AS resin. If it exceeds 45 parts by weight, the fluidity is lowered and the workability is poor, which is not preferable.

Next, the multi-component polymer which is the component (B) of the styrene resin composition of the present invention will be described. The multi-component polymer is an acrylic rubber-like polymer containing an acrylic acid alkyl ester monomer as a main component, at least one or more selected from the group consisting of methacrylic acid alkyl ester, aromatic vinyl, and unsaturated nitrile. It is a polymer obtained by graft-polymerizing a monomer. Graft polymerization may be performed in one step or in two or more steps.

Styrene containing this multi-component polymer as a copolymerization component of the acrylic acid alkyl ester monomer and / or the methacrylic acid alkyl ester monomer which is the component (A) of the styrene resin composition of the present invention. By using it as an impact resistance improver for a styrene resin, it becomes possible to improve the weather resistance of the styrene resin and at the same time improve the impact resistance. Here, the alkyl acrylate, which is the main component of the acrylic rubber-like polymer, preferably has an alkyl group having 2 to 12 carbon atoms. At this time, the alkyl group is
It may be linear or branched. Examples of alkyl acrylates include, for example, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, pentyl acrylate, hexyl acrylate, acrylic acid 2 -Ethylhexyl, n-octyl acrylate, cyclohexyl acrylate and the like can be mentioned. Among these, n-butyl acrylate is particularly preferable because it can be obtained at a relatively low cost and exhibits high rubber elasticity.

The acrylic rubber-like polymer may be used in combination of two or more kinds of acrylic acid alkyl ester monomers. Further, it may be a copolymer with a monomer copolymerizable therewith. As the copolymerizable monomer,
For example, methacrylic acid alkyl ester, styrene, α
-Aromatic vinyl monomers such as methylstyrene, acrylonitrile, unsaturated nitrile monomers such as methacrylonitrile, methacrylamide monomers, vinyl ether monomers,
Vinyl ester etc. can be mentioned. Further, conjugated diolefin monomers such as butadiene and isoprene can also be mentioned. However, the conjugated diolefin monomer tends to lower the weather resistance and is not necessarily a preferable copolymerization component, but it has a large effect of increasing the impact resistance, does not require high weather resistance, and has high impact resistance. It can be used for applications requiring high performance.

The monomer graft-polymerized to the acrylic rubber-like polymer is basically selected from one or more groups selected from the group consisting of alkyl methacrylate, aromatic vinyl, and unsaturated nitrile. The methacrylic acid alkyl ester preferably has an alkyl group having 2 to 4 carbon atoms. At this time, the alkyl group may be linear or branched. Examples of the alkyl methacrylate may include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, i-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate and the like. Among these, methyl methacrylate is most preferable because it is available at a relatively low cost and has excellent heat resistance and thermal stability. As aromatic vinyl, in addition to styrene, o-methylstyrene, m-methylstyrene,
Nuclear alkyl-substituted styrenes such as p-methylstyrene, 2,4-dimethylstyrene, ethylstyrene and p-tert-butylstyrene, α-alkylsubstituted styrenes such as α-methylstyrene and α-methyl-p-methylstyrene, etc. Can be mentioned. Of these, styrene is the cheapest available and most preferred. Examples of unsaturated nitriles include acrylonitrile and methacrylonitrile. Of these, acrylonitrile is the cheapest available and most preferred. The above-mentioned methacrylic acid alkyl ester, aromatic vinyl and unsaturated nitrile may be used alone or in combination of two or more of the same kind or different kinds.

The monomer to be graft-polymerized may contain other monomer copolymerizable with these monomers.
Examples of other monomers include amides such as alkyl acrylate, acrylamide and methacrylamide, alkyl vinyl ethers, alkyl vinyl esters, vinyl halides and vinylidene halides. Further, a monomer having a functional group for the purpose of improving the interfacial adhesion with the styrene resin, for example, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, ethylene glycol diglycidyl ether, acrylic acid, methacrylic acid, etc. are also mentioned. be able to. The multi-component polymer grafted with the monomer having this functional group coexisting is effective in further improving the impact resistance of the styrene resin composition of the present invention.

The multi-component polymer which is the component (B) of the styrene resin composition of the present invention is produced, for example, as follows. However, the method is not limited to this. Generally produced by emulsion polymerization. For example, first, polymerization is performed in the coexistence of a monomer containing an alkyl acrylate as a main component, a polyfunctional crosslinking agent, and a polymerization initiator to obtain a latex of an acrylic rubber-like polymer. Then in this latex,
Alkyl methacrylate, aromatic vinyl, one or more monomers selected from the group consisting of unsaturated nitriles, a polymerization initiator, if necessary, a polyfunctional crosslinking agent is added and polymerized, and then salting out, It can be manufactured by washing and drying. Alternatively, after aggregating or salting out and separating the latex, at least one monomer selected from the group consisting of alkyl methacrylate, aromatic vinyl, and unsaturated nitrile, a polymerization initiator, and optionally a polyfunctional crosslinking agent. It can be produced by a method such as polymerization in the presence of an agent. At this time, the polyfunctional crosslinking agent is not always essential, but the combined use of the polyfunctional crosslinking agent increases the impact resistance of the styrene resin composition of the present invention, and is therefore more preferable.

As the polyfunctional crosslinking agent, ethylene glycol diacrylate, diethylene glycol diacrylate, 1,3-butylene glycol diacrylate, trimethylolpropane triacrylate, polyethylene glycol diacrylate (for example, a molecular weight of 200 to 6) is used.
00) and other polyhydric alcohol di- or triacrylates, and polyhydric alcohol di-acrylates corresponding to the above acrylic acid.
Or trimethacrylates, divinyl ethers of polyhydric alcohols such as ethylene glycol divinyl ether, divinyl adipate, diallyl phthalate, diallyl maleate, diallyl fumarate, diallyl esters of organic dicarboxylic acids such as diallyl sebacate, trially Lucyanurate, triallyl isocyanurate, triallyl such as triallyl phosphate, allyl methacrylate, allyl acrylate, allyl itaconate, monoallyl fumarate, allyl esters of carboxylic acid such as monoallyl maleate, divinylbenzene, Examples thereof include diallyl ether. This polyfunctional crosslinking agent can be used alone or in combination of two or more.

The emulsifier used in emulsion polymerization is not particularly limited, and any one can be selected from those generally used in emulsion polymerization. Examples thereof include long-chain alkylcarboxylic acid salts, sulfosuccinic acid alkyl ester salts, and alkylbenzene sulfonic acid salts. Also, the polymerization initiator is not particularly limited, and a commonly used inorganic initiator such as water-soluble persulfate or perborate alone or in combination with sulfite, thiosulfate or the like is used. It can be used as a redox initiator system. Furthermore,
Redox initiator systems such as soluble organic peroxide / sodium sulfoxylate can also be used.

The particle size of the multi-component polymer is 0.0
1 to 1.0 μm is preferable. Also, 0.02-0.5μ
m is more preferred. Furthermore, 0.03 to 0.2 μm is particularly preferable. Further, in the present invention, two or more kinds of multi-component polymers having different compositions, particle sizes and the like can be used. The styrene-based resin composition of the present invention basically comprises at least a styrene-based resin which is the component (A) and a multi-component polymer which is the component (B). A) component is 95 to 5 parts by weight, preferably 90 to
25, more preferably 90 to 40 parts by weight, and the component (B) is 5 to 95 parts by weight, preferably 10 to 75 parts by weight, more preferably 10 to 60 parts by weight. However, at this time,
The total of the components (A) and (B) is 100 parts by weight.
When the amount of the component (A) exceeds 95 parts by weight or the amount of the component (B) is less than 5 parts by weight, the effect of improving the impact resistance of the styrene resin is not sufficient. When the amount of the component (A) is less than 5 parts by weight or the amount of the component (B) exceeds 95 parts by weight, the rigidity is low and the performance required as a styrene resin is not satisfied.

The styrenic resin composition of the present invention comprises the styrene resin as the component (A) and the multi-component polymer as the component (B) as basic components, and the third component coexists therein. You may. As the third component, (C) at least a first layer is an acrylic resin containing a methacrylic acid alkyl ester monomer as a main component, and a second layer is an acrylic rubber containing a acrylate alkyl ester monomer as a main component. A preferred example is a polymer, and a multi-layer polymer in which the third layer is an acrylic resin containing a methacrylic acid alkyl ester monomer as a main component. The effect of increasing the impact resistance of the styrene resin is low in the multi-layer polymer as the component (C), as compared with the multi-component polymer as the component (B). However, the multicomponent polymer which is the component (B) and the component (C)
When it is used in combination with the multi-layered polymer as a component, a material having more excellent weather resistance and impact resistance can be obtained with the same amount of the improver added. It is not clear why this combination system improves weather resistance and impact resistance. However, the reason for this is presumed as follows. That is, the styrene resin, which is the component (A) of the composition of the present invention, has improved weather resistance by copolymerizing an acrylic acid alkyl ester monomer and / or a methacrylic acid alkyl ester monomer. When the multi-component polymer as the component B) contains an acrylic rubber-like polymer as a main component, the weather resistance of the styrene resin is
Since the multi-component polymer is acrylic, it does not exceed its weather resistance. Therefore, although the weather resistance tends to be further improved by adding the component (B) to the component (A), the multi-layer polymer of the component (C) contains a large amount of the component (B) in the styrene resin. Improving the dispersibility of the component-based polymer, that is,
By preventing the aggregation of the multi-component polymer of the component (B) and by uniformly dispersing it in the styrene resin, discoloration of the styrene resin is prevented, and the impact resistance is also improved by this uniform dispersion. I presume it is.

As described above, in the multi-layer polymer as the component (C), at least the first layer, which is the innermost layer, has an acrylic resin (hard layer) containing a methacrylic acid alkyl ester monomer as a main component, and a second layer. Acrylic rubbery polymer whose layer is mainly composed of acrylic acid alkyl ester monomer (soft layer),
The third layer is an acrylic resin (hard layer) containing a methacrylic acid alkyl ester monomer as a main component. Here, this multi-layered polymer is an acrylic rubber-like polymer (soft layer) containing an acrylic acid alkyl ester as a main component or an acrylic type containing a methacrylic acid alkyl ester monomer as a main component on the three layers. A fourth layer made of resin (hard layer),
It is also possible to provide a fifth layer. Here, the hard layer, which is the first layer or the third layer, is an acrylic resin whose main component is a methacrylic acid alkyl ester monomer, and the methacrylic acid alkyl ester monomer has a carbon number of an alkyl group. Those of 2 to 4 are preferable. At this time, the alkyl group may be linear or branched. Examples of alkyl methacrylates include, for example, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate,
I-propyl methacrylate, n-butyl methacrylate,
Examples thereof include i-butyl methacrylate. Among these, methyl methacrylate is most preferable because it is available at a relatively low cost and has high heat resistance and thermal stability. This hard layer has an methacrylic acid alkyl ester monomer as a main component, but may be a copolymer with another monomer that is copolymerized therewith. As the other copolymerizable monomer, an acrylic acid alkyl ester is most preferable because it has an effect of improving thermal stability. Examples of alkyl acrylates include methyl acrylate, ethyl acrylate, n-propyl acrylate, i-propyl acrylate, n-butyl acrylate, i-butyl acrylate, 2-ethylhexyl acrylate, and the like. it can. Among these, methyl acrylate, ethyl acrylate, and acrylic acid n-butyl acrylate are preferably used. The amount of the other copolymerizable monomer is preferably 0.1 to 20% by weight, more preferably 0.5 to 15% by weight, still more preferably 0.
It is 5 to 10% by weight.

The soft layer, which is the second layer, is an acrylic rubber-like polymer whose main component is an acrylic acid alkyl ester monomer. Those having 2 to 12 carbon atoms are preferable. The alkyl group may be linear or branched. Examples of alkyl acrylate include, for example, ethyl acrylate, n-propyl acrylate, acrylic acid i.
-Propyl, n-butyl acrylate, i-butyl acrylate, pentyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate,
Examples thereof include cyclohexyl acrylate. Among these, n-butyl acrylate is particularly preferable because it can be obtained at a relatively low cost and exhibits high rubber elasticity.
The acrylic acid alkyl ester monomer may be copolymerized with one kind or two or more kinds.

The acrylic rubber-like polymer may be a homopolymer of an acrylic acid alkyl ester monomer,
Further, it may be a copolymer with another monomer copolymerizable therewith. As other copolymerizable monomers, methacrylic acid alkyl ester, styrene, p-methylstyrene, 2,4-dimethylstyrene, ethylstyrene, p-
Aromatic vinyl such as nuclear alkyl-substituted styrene such as tert-butyl styrene, α-alkyl styrene such as α-methyl styrene, α-methyl-p-methyl styrene, and the like. When aromatic vinyl is used as a copolymerization component, styrene is the most inexpensive and particularly preferred. When these monomers are copolymerized, the amount thereof is preferably in the range of 0 to 30% by weight. Thirty
If it exceeds 5% by weight, the rubber elasticity of the acrylic rubber-like polymer is lowered, and when it is used together with the component (B) as an impact resistance improver, the impact resistance improving effect of the styrene resin composition of the present invention is decreased. .

As described above, the multi-layer polymer which is the component (C) is basically a first acrylic resin mainly containing at least an alkyl methacrylate monomer.
A layer, a second layer made of an acrylic rubber polymer mainly containing an alkyl acrylate monomer, and a third layer made of an acrylic resin mainly containing an alkyl methacrylate monomer, At this time, these quantitative ratios are
The first layer is 3 to 37 parts by weight, the second layer is 94 to 20 parts by weight,
The third layer is preferably 3 to 43 parts by weight. Also, the first layer is 5
-18 parts by weight, second layer 90 to 40 parts by weight, third layer 5
˜42 parts by weight is more preferred. Further, the first layer is 5-14
Parts by weight, 89 to 45 parts by weight for the second layer, 6 to 41 for the third layer
Part by weight is particularly preferred. If the first layer and the third layer are less than 3 parts by weight or the second layer is 94 parts by weight or more,
When the rubber layer is used in combination with the component (B) as an impact resistance improver for the reason that it is easily deformed or agglomerated,
The effect of improving the impact resistance of the styrene resin composition of the present invention is low. When the first layer is more than 37 parts by weight and the third layer is more than 43 parts by weight or the second layer is less than 20 parts by weight, the rubber elasticity is poor and when used in combination with the component (B) as an impact resistance improver. The effect of improving the impact resistance of the styrene resin composition of the present invention is low.

The multi-layer polymer as the component (C) is generally produced by emulsion polymerization by a seed polymerization method. Although not limited to this method, for example, it can be produced by the following method. First, a monomer containing a methacrylic acid alkyl ester as a main component is polymerized in the coexistence of a polymerization initiator and, if necessary, a polyfunctional crosslinking agent to form an acrylic resin for the first layer (hard layer). Next, a monomer containing an acrylic acid alkyl ester as a main component, a polymerization initiator, and a polyfunctional crosslinking agent are added and polymerized to form an acrylic rubber-like polymer of the second layer (soft layer). Then
Monomers mainly composed of methacrylic acid alkyl ester,
A polymerization initiator and, if necessary, a polyfunctional crosslinking agent are added and polymerized to form an acrylic resin for the third layer (hard layer). When forming the fourth layer and the fifth layer, the layers are formed by the same method. After that, it can be produced by performing treatments such as salting out, washing, and drying.

At this time, as the polyfunctional crosslinking agent, the same type as the polyfunctional crosslinking agent described in the above (B) component is used. As the emulsifier and the polymerization initiator used in the emulsion polymerization, the same types of emulsifiers and polymerization initiators as those described in the component (B) are used. By crosslinking, when used in combination with the component (B) as an impact resistance improver, the impact resistance improving effect of the styrene-based thermoplastic resin composition of the present invention is improved. The particle diameter of the multilayer polymer is preferably 0.01 to 1.0 μm. Moreover, 0.02-0.5 micrometer is more preferable. Furthermore, 0.03 to 0.2 μm is particularly preferable. Also,
In the present invention, as the multi-layer polymer, two or more kinds having different compositions, particle sizes and the like can be used.

When the styrenic resin composition of the present invention is used in combination with the multi-layer polymer which is the component (C), the amount ratio of the composition is such that the component (A) is 95 to 5 parts by weight, and the component (B) is The ingredients are
5 to 95 parts by weight, and the component (C) is 1 to 50 parts by weight. However, the total of the components (A), (B) and (C) is 100 parts by weight. When the amount of the component (C) is less than 1 part by weight or exceeds 50 parts by weight, the combined use effect of the component (B) and the component (C), that is, the styrene resin composition of the present invention has high weather resistance and high It lacks the effect of being an impact resistant material.

The styrene resin composition of the present invention comprises (A)
1 to 100 parts by weight of another thermoplastic resin can be added to the total of 100 parts by weight of the component + (B) component or the total of 100 parts by weight of the (A) component + (B) component + (C). . Examples of the thermoplastic resin that can be added include styrene resins other than the styrene resin composition of the present invention (for example, AES resin, AAS resin, etc.), polyolefin resins, polyamide resins, polyester resins, polyacetal resins, Examples thereof include polyphenylene oxide resin and acrylic resin. At this time, various compatibilizers can be used if necessary. The styrene resin composition of the present invention has a total of 10 components (A) + (B).
It is also possible to add 1 to 100 parts by weight of the rubber component with respect to 0 parts by weight or a total of 100 parts by weight of the component (A) + the component (B) + (C). Examples of rubber components that can be added include hydrogenated block copolymers such as hydrogenated styrene-isoprene block copolymers and hydrogenated styrene-butadiene block copolymers, olefin elastomers, and EPDM grafted with AS. Examples thereof include a graft copolymer.

The styrene resin composition of the present invention is excellent in weather resistance, but the weather resistance is evaluated by using a tester such as a method in which a molded product is left outdoors to measure discoloration, a sunshine carbon or a xenon lamp. To measure discoloration,
There is a method of measuring discoloration using a super accelerated weathering tester using a metal halide lamp. The method of leaving the molded product outdoors and measuring the discoloration is close to practical conditions, but it takes too much time for evaluation. However, the method of measuring discoloration using a super-accelerated weathering tester using a metal halide lamp is preferable because the state of being left outdoors can be expressed in a short period of time.

The styrene resin composition of the present invention can be obtained by melt mixing using a single-screw or twin-screw extruder. The styrenic resin composition of the present invention includes various compounding agents known per se, such as calcium carbonate, calcium silicate, clay, kaolin, talc, silica,
Diatomaceous earth, mica powder, asbestos, alumina, barium sulfate, calcium sulfate, basic magnesium carbonate, molybdenum disulfide, graphite, glass fibers, carbon fibers, glass spheres, silas balloons, fillers such as carbon fibers, carbon black, oxidation Titanium, zinc white, red iron oxide, ultramarine, dark blue, azo pigment, nitroso pigment, lake pigment, phthalocyanine pigment, phenol-based, sulfite-based, phosphite-based, amine-based heat-resistant stabilizer, antioxidant, light stabilizer, An ultraviolet absorber, a foaming agent, an antistatic agent, a metal soap, a lubricant such as wax, and the like can be added.

The styrene resin composition of the present invention is a building material such as rain gutter, window frame, sash frame, sill, outer wall material, floor material, interior material, exterior material, decoration material, deck material, fence material, terrace material and the like. , Furniture, office equipment, machine parts, housings of various devices, automobile materials, road signs, etc. Further, the styrene-based resin composition of the present invention is used in a molded product obtained by an ordinary molding method such as an injection molded product, an extrusion molded product, a blow molded product, a vacuum molded product, a film molded product, and a foamed sheet molded product. be able to. It can also be used by laminating with another resin. In particular, for lamination, it is possible to obtain a highly weather-resistant product by using inexpensive HIPS or ABS as the base material and using the styrene resin composition of the present invention as the skin.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In these examples and comparative examples, the test methods used for evaluating various physical properties, the raw materials, and the method for producing the thermoplastic elastomer used for compounding are as follows. Moreover, "part" represents a part by weight.

1. Test method (1) Tensile yield stress [MPa] Evaluation was performed at 23 ° C according to ISO527-1. (2) Bending strength [MPa] According to ISO178, it was evaluated at 23 ° C. (3) Flexural modulus [MPa] Evaluation was performed at 23 ° C according to ISO178. (4) Charpy impact strength [KJ / m ² ] It was evaluated at 23 ° C. according to ISO179. (5) Weather resistance A weather resistance test was conducted under the following conditions using a metal weather (manufactured by Daipla Wintes Co., Ltd.) which is a super accelerated weather resistance tester using a metal halide lamp. As the test piece, a flat plate having a width of 5 cm, a length of 9 cm and a thickness of 3 mm was used.

[Irradiation conditions] One cycle with an output of 75 mW / cm ² was performed at a black panel temperature of 63 ° C. and a humidity of 50% 4.
Irradiation → 30 seconds water shower → Black panel temperature 30
25 cycles (20 cycles)
At 0 hours), the change in color from before irradiation, that is, ΔE was measured. The smaller the ΔE, the better the weather resistance. [Color difference measurement] is made by Minolta color difference meter CR-300 (standard light source D
65) was used.

2. Raw material (1) Styrene resin (a) Polystyrene (trade name: GP68) manufactured by Asahi Kasei Corporation
5) (PS) (b) High-impact polystyrene manufactured by Asahi Kasei Co., Ltd. (trade name:
H8762) (referred to as HIPS) (c) Prototype of Asahi Kasei Co., Ltd. Styrene / methyl methacrylate copolymer (15% by weight of methyl methacrylate) (S
M-1) (d) Asahi Kasei Corp. prototype styrene / n-butyl acrylate copolymer (n-butyl acrylate 5% by weight)
(Referred to as SB-1) (e) Asahi Kasei Co., Ltd. prototype styrene / n-butyl acrylate copolymer (n-butyl acrylate 15% by weight)
(Referred to as SB-2) (f) Asahi Kasei Corp. prototype styrene / acrylonitrile /
n-butyl acrylate copolymer (acrylonitrile 2
7% by weight, 10% n-butyl acrylate) (referred to as ASB)

(2) Multi-component polymer (a) Multi-component polymer A-1 In a pressure resistant reactor equipped with a stirring blade, n-butyl acrylate 650 was used.
0 part, ethylene glycol dimethacrylate 20 parts, diisopropylbenzene hydroperoxide 19.5
Parts, ferrous sulfate 0.2 parts, ethylenediamine tetraacetate acid sodium salt 4.9 parts, formaldehyde sodium sulfoxylate 4.9 parts, potassium oleate 90 parts, sodium pyrophosphate 10 parts, ion-exchanged water 17500 A part was charged and polymerization was carried out at 45 ° C. for 16 hours. Methyl methacrylate 1500 was added to the obtained latex.
Parts, 12 parts of ethylene glycol dimethacrylate, 1.5 parts of diisopropylbenzene hydroperoxide,
0.5 parts of formaldehyde sodium sulfoxylate was added, and the polymerization was continued at 60 ° C. for 7 hours. The latex obtained is salted out, washed and dried to give a multi-component polymer A-1.
Got

(B) Multicomponent polymer A-2 A pressure-resistant reactor equipped with a stirring blade was charged with n-butyl 650 acrylate.
0 part, ethylene glycol dimethacrylate 20 parts, diisopropylbenzene hydroperoxide 19.5
Parts, ferrous sulfate 0.2 parts, ethylenediamine tetraacetate acid sodium salt 4.9 parts, formaldehyde sodium sulfoxylate 4.9 parts, potassium oleate 90 parts, sodium pyrophosphate 10 parts, ion-exchanged water 17500 A part was charged and polymerization was carried out at 45 ° C. for 16 hours. 1,200 parts of styrene, 300 parts of n-butyl acrylate, 500 parts of acrylonitrile,
15 parts of ethylene glycol dimethacrylate, 2 parts of diisopropylbenzene hydroperoxide, 1 part of formaldehyde sodium sulfoxylate are added, and 6 parts are added.
Polymerization was continued at 0 ° C. for 5 hours. The obtained latex was salted out, washed and dried to obtain a multi-component polymer A-2.

(C) Multicomponent polymer A-3 In a pressure resistant reactor equipped with a stirring blade, n-butyl acrylate 650 was added.
0 part, 1,3-butanediol diacrylate 65 parts,
Diisopropylbenzene hydroperoxide 20
Parts, ferrous sulfate 0.2 parts, ethylenediamine tetraacetate acid sodium salt 0.3 parts, formaldehyde sodium sulfoxylate 0.5 parts, potassium oleate 90 parts, sodium pyrophosphate 10 parts, ion-exchanged water 17,000 A part was charged and the polymerization was carried out at 45 ° C. for 15 hours. 1100 parts of styrene, 500 parts of methyl methacrylate, 400 parts of acrylonitrile, 15 parts of ethylene glycol dimethacrylate, 2 parts of diisopropylbenzene hydroperoxide, and 1 part of formaldehyde sodium sulfoxylate were added to the obtained latex,
Polymerization was continued at 4 ° C for 4 hours. Furthermore, 1500 parts of methyl methacrylate, ethylene glycol dimethacrylate 11
Parts, 1.5 parts of diisopropylbenzene hydroperoxide and 0.5 parts of formaldehyde sodium sulfoxylate were added, and the polymerization was continued at 60 ° C. for 4 hours.
The obtained latex was salted out, washed and dried to obtain a multi-component polymer A-3.

(D) Multicomponent polymer A-4 A pressure resistant reactor equipped with stirring blades was charged with n-butyl 650 acrylate.
0 part, ethylene glycol dimethacrylate 20 parts, diisopropylbenzene hydroperoxide 19.5
Parts, ferrous sulfate 0.2 parts, ethylenediamine tetraacetate acid sodium salt 4.9 parts, formaldehyde sodium sulfoxylate 4.9 parts, potassium oleate 90 parts, sodium pyrophosphate 10 parts, ion-exchanged water 17500 A part was charged and polymerization was carried out at 45 ° C. for 16 hours. To the obtained latex, 3.5 parts of sodium sulfosuccinate dioctyl ester was added for stabilization, and then a 2% tartaric acid aqueous solution and a 2% sodium hydroxide aqueous solution were added to agglomerate the latex. Then, methyl methacrylate 17
00 parts, glycidyl methacrylate 300 parts, ethylene glycol dimethacrylate 12 parts, diisopropylbenzene hydroperoxide 2 parts, formaldehyde sodium sulfoxylate 1 part, sodium sulfosuccinate dioctyl ester are added, and polymerization is continued at 45 ° C. for 16 hours. did. Methyl methacrylate 1 was added to this latex.
500 parts, ethylene glycol dimethacrylate 10
Parts and 1.5 parts of diisopropylbenzene hydroperoxide were added, and the polymerization was continued at 45 ° C. for 16 hours.
The obtained latex was salted out, washed and dried to obtain a multi-component polymer A-4.

(3) Multilayer polymer (a) Multilayer polymer B-1 A pressure-resistant reactor equipped with a stirring blade was charged with methyl methacrylate 528.
Parts, n-butyl acrylate 6.6 parts, allyl methacrylate 0.5 parts, diisopropylbenzene hydroperoxide 0.5 parts, sodium dioctyl sulfosuccinate 50 parts, sodium formaldehyde sodium sulfoxylate 3.4 parts, ions First, 15,000 parts of exchanged water was charged and polymerized at 80 ° C. for 20 minutes to form a first layer. Next, 2.8 parts of sodium formaldehyde was added, and then 3900 parts of n-butyl acrylate and styrene 910.
Part, allyl methacrylate 19 parts, polyethylene glycol diacrylate (molecular weight 200) 116 parts, and diisopropylbenzene hydroperoxide 5 parts were continuously fed to the polymerization reactor over 2 hours,
The polymerization reaction was further performed at 90 ° C. for 90 minutes to complete the reaction and form the second layer. Next, 1600 parts of methyl methacrylate, 20 parts of n-butyl acrylate, 1.5 parts of diisopropylbenzene hydroperoxide and n
30 parts of a mixture consisting of 2.0 parts of octyl mercaptan
The mixture was continuously fed to the polymerization reactor over a period of 30 minutes, and the polymerization reaction was further performed at 80 ° C. for 30 minutes to form a third layer and complete the polymerization. The obtained latex was salted out, washed and dried to obtain a multilayer polymer B-1.

(B) Multilayer polymer B-2 A pressure-resistant reactor equipped with a stirring blade was charged with methyl methacrylate 528.
Parts, n-butyl acrylate 6.6 parts, allyl methacrylate 0.5 parts, diisopropylbenzene hydroperoxide 0.5 parts, sodium dioctyl sulfosuccinate 50 parts, sodium formaldehyde sodium sulfoxylate 3.4 parts, ions 15,000 parts of exchanged water was charged and polymerized at 80 ° C. for 20 minutes to form a first layer. Next, 2.8 parts of sodium formaldehyde was added, and then 3900 parts of n-butyl acrylate and styrene 910.
Part, allyl methacrylate 19 parts, polyethylene glycol diacrylate (molecular weight 200) 116 parts, and diisopropylbenzene hydroperoxide 5 parts were continuously fed to the polymerization reaction over 2 hours at 80 ° C.
Polymerization reaction for 90 minutes to complete the reaction,
A second layer was formed. Then, methyl methacrylate 52
A mixture of 8 parts, n-butyl acrylate (6.4 parts) and diisopropylbenzene hydroperoxide (0.5 parts) was continuously supplied to the polymerization reactor over 30 minutes,
The polymerization reaction was carried out at 20 ° C. for a further 20 minutes to form the third layer. Further, a monomer mixture consisting of 1060 parts of methyl methacrylate, 13 parts of n-butyl acrylate, 1 part of diisopropylbenzene hydroperoxide and 3.2 parts of n-octyl mercaptan was continuously polymerized over 30 minutes. And a polymerization reaction was further performed at 80 ° C. for 20 minutes to form a fourth layer and complete the reaction. The obtained latex was salted out, washed and dried to obtain a multilayer polymer B-2.

(4) Impact-resistant acrylic resin (a) manufactured by Asahi Kasei Co., Ltd. Impact-resistant acrylic resin (trade name: Delpet SR8500) acrylic resin / acrylic multilayer polymer = 50/50 (weight ratio) (HI-PMM
Called A. (5) AES resin (a) Techno Polymer Co., Ltd. AES110 (referred to as AES)

[0048]

Examples 1 to 17 and Comparative Examples 1 to 5 Styrene-based resins and styrene-based resins were mixed with a multi-component polymer and a multi-layered polymer at the ratios shown in Tables 1 to 3, and the resin temperature was 230 ° C. Melt mixing and pelletizing were performed using a twin-screw extruder set so that Injection molding machine (Toshiba IS
45 PNV) to obtain a molded product. The characteristics of the molded product are shown in Tables 1 to 3. The impact-resistant acrylic resin is
The manufactured product was used as it was. Regarding the styrene resin and the composition of the present invention, the following additives (a) to (e) were commonly added to 100 parts by weight of the resin or the composition. (a) Hindered amine light stabilizer: 0.4 parts by weight of bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate (b) Benzotriazole ultraviolet absorber: 2- (2H-benzotriazole- 2-yl) -p-cresol 0.2 parts by weight (c) hindered phenolic antioxidant: octadecyl-
3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate 0.1 part by weight (d) Phosphorus processing heat stabilizer: tris (2,4-di-tert-butylphenyl) phosphite 0 1 part by weight (e) Pigment: titanium oxide / ethylene bisstearic acid amide (weight ratio 80/20) 3.0 parts by weight

[0049]

[Table 1]

[0050]

[Table 2]

[0051]

[Table 3]

[0052]

Industrial Applicability The styrene resin composition of the present invention exhibits excellent weather resistance and excellent impact resistance, and is suitable for building materials, home electric appliances, O
It can be used for a wide variety of purposes including equipment A, automobile materials, and miscellaneous goods, and plays a major role in the industrial world.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4J002 BC04W BC06W BC07W BN03X                       BN11X BN21Y GN00 GQ00

Claims (9)

[Claims] 1. A styrene resin 95 to 5 parts by weight containing (A) an acrylic acid alkyl ester monomer and at least one of a methacrylic acid alkyl ester monomer as a copolymerization component, and (B) an acrylic acid alkyl ester. A polymer obtained by graft-polymerizing at least one monomer selected from the group consisting of at least alkyl methacrylate ester, aromatic vinyl, and unsaturated nitrile onto an acrylic rubber-like polymer containing a monomer as a main component. Containing 5 to 95 parts by weight of component type polymer, the total amount of the component (A) and the component (B) is 100.
A styrene resin composition that is part by weight. 2. Further, (C) at least a first layer is an acrylic resin containing a methacrylic acid alkyl ester monomer as a main component, and a second layer is an acrylic rubber-like one containing an acrylic acid alkyl ester monomer as a main component. The polymer, the third layer contains 1 to 50 parts by weight of a multi-layered polymer made of an acrylic resin whose main component is a methacrylic acid alkyl ester monomer, and contains (A) component, (B) component, and (C). ) The styrene resin composition according to claim 1, wherein the total amount of the components is 100 parts by weight. 3. A styrene-based resin (A) whose main component is a co-polymer composed of an aromatic vinyl monomer and at least one of an acrylic acid alkyl ester monomer and a methacrylic acid alkyl ester monomer. The copolymer or the main component thereof is a copolymer composed of an aromatic vinyl monomer, an unsaturated nitrile monomer, and at least one kind of an acrylic acid alkyl ester monomer and a methacrylic acid alkyl ester monomer. The styrene resin composition according to claim 1. 4. The copolymerization component of (A) styrene resin is
The styrene-based resin composition according to claim 1, which is an alkyl acrylate. 5. The copolymerization component of (A) styrene resin is
The styrene-based resin composition according to claim 4, which is n-butyl acrylate. 6. The styrene according to claim 1, wherein the acrylic acid alkyl ester, which is the main component of the acrylic rubber-like polymer of the multi-component polymer (B), is n-butyl acrylate. -Based resin composition. 7. The styrene resin composition according to claim 1, wherein the (B) alkyl methacrylate ester as a graft component of the multi-component polymer is methyl methacrylate. 8. The method according to claim 2, wherein the alkyl methacrylate of the multi-layer polymer (C) is methyl methacrylate.
7. The styrene resin composition according to any one of 7. 9. The acrylic acid alkyl ester of the multilayer polymer (C) is n-butyl acrylate.
8. The styrene resin composition according to any one of 8.