JPH06192348A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition comprising a thermoplastic resin and a specific impact resistance-improving agent in a specified ratio, excellent in impact resistance and moldability and useful for moldings, etc. CONSTITUTION:This resin composition comprises (A) 100 pts.wt. of a thermoplastic resin such as a vinyl chloride resin and (B) 3-50 pts.wt. of an impact resistance-improving agent comprising a multi-layered graft copolymer produced by graft-polymerizing two or more grafted layers on a polybutadienic elastomer comprising the copolymer of >=50wt.% of (poly) butadiene and <=50wt.% of other copolymerizable vinylic compounds and containing 0-5wt.% of a crosslinking agent, where the grafted layers are composed of one or more monomers selected from a group of monomers consisting of an alkyl (meth) acrylate, an aromatic vinyl compound, a vinyl cyanide compound and butadiene and each of the grafted layers contains 0-5wt.% of the crosslinking agent, and the glass transition temperature of a polymer constituting the outermost layer being <=0 deg.C, and the glass transition temperature of the polymer constituting the second layer from the outermost layer being >=60 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition having good impact resistance and moldability.

[0002]

2. Description of the Related Art Thermoplastic resins, particularly vinyl chloride resins (hereinafter abbreviated as PVC) are widely used as general-purpose resins, but their mechanical properties are not always satisfactory. That is, PVC is inferior in impact strength, especially impact strength with a notch, and various methods have been proposed for the purpose of improving such impact strength.

The most effective method of these proposals is a method of mixing a PVC with a multilayer graft copolymer obtained by graft-polymerizing a monomer such as styrene, methyl methacrylate, acrylonitrile or the like to a conjugated diene elastic body. Such a multilayer graft copolymer has already been marketed as an impact resistance modifier for PVC, and has greatly contributed to the expansion of applications of PVC molded articles.

By the way, in profile extrusion applications, there is a demand for a composition having a high impact strength even when molded under the condition that it is extremely slippery and does not work well.
The hitherto proposed impact modifiers are not sufficiently satisfactory. That is, a multilayer graft copolymer obtained by graft-polymerizing a resin component having good compatibility with PVC on an elastic body as a conventional impact modifier is processed at a high temperature or when a relatively small amount of a lubricant is used. While the multi-layered graft copolymer is uniformly dispersed in PVC and shows good impact resistance, the multi-layered graft copolymer does not aggregate in PVC when it is processed at low temperature or when a large amount of lubricant is used. However, it shows almost no impact resistance.

[0005]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention The inventors of the present invention have conducted extensive studies based on the idea that it is most effective to improve the impact resistance by uniformly dispersing such a multilayer graft copolymer in PVC. The outermost layer has a glass transition temperature (hereinafter abbreviated as Tg) of 0 ° C. or lower than that of the multi-layered graft copolymer, which is PVC.
When blending with and molding, it is of course that the dispersed state is good even under high kneading molding conditions, and even when the kneading is low and the shear stress is low, the multi-layered graft copolymer easily melts quickly, and the gel The inventors have found that the present invention can be a molded product which is accelerated in polymerization, has an excellent dispersed state, exhibits high impact strength under a wide range of molding conditions, has good processability, and has excellent surface gloss.

[0006]

SUMMARY OF THE INVENTION The gist of the present invention is that polybutadiene or butadiene 50% by weight containing 100 parts by weight of a thermoplastic resin and 0-5% by weight of a crosslinking agent.
50% by weight of the above and other vinyl compounds copolymerizable therewith
A multi-layered graft copolymer obtained by graft-polymerizing at least two graft layers to a butadiene-based elastic body (A) composed of the following copolymers, wherein the graft layer is an acrylic acid alkyl ester, a methacrylic acid alkyl ester, or an aroma. It is composed of monomers selected from the group of monomers consisting of group vinyl compounds, vinyl cyan compounds and butadiene, and each graft layer contains 0 to 5% by weight of a crosslinking agent for each layer.
It is characterized in that the Tg of the polymer contained and constituting the outermost layer (C) is 0 ° C. or lower, and the Tg of the polymer constituting the second layer (B) from the outermost layer (C) is 60 ° C. or higher. The impact resistance modifier is 3 to 50 parts by weight, and the thermoplastic resin composition has good impact resistance and good moldability.

It is essential that the impact modifier of the present invention has a multilayer structure of three or more layers obtained by polymerizing at least three steps, and of course, the graft layers are three layers or four layers. It does not matter, as long as the polymer structure of the outermost layer has a Tg of 0 ° C. or lower and the second layer of the polymer counted from the outermost layer has a Tg of 60 ° C. or higher. Other monomers or monomer mixtures may of course be polymerized in multiple stages depending on the purpose so long as they fall within the Tg range.

The monomer group constituting the impact modifier of the present invention is composed of an alkyl acrylate ester, an alkyl methacrylate ester, an aromatic vinyl compound, a vinyl cyan compound and butadiene.

The alkyl acrylate is preferably one having an alkyl group having 2 to 10 carbon atoms, for example, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, hexyl acrylate, acrylic acid. Examples include octyl and 2-ethyl-hexyl acrylate.

As the methacrylic acid alkyl ester,
An alkyl group having 1 to 4 carbon atoms is preferable, and examples thereof include methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, and tert-butyl methacrylate. To be Methyl methacrylate is particularly preferable in consideration of compatibility with PVC.

Examples of the aromatic vinyl compound include styrene, α-substituted styrene, nucleus-substituted styrene and derivatives thereof such as α-methylstyrene, chlorostyrene and vinyltoluene.

Further, examples of the vinyl cyan compound include acrylonitrile and methacrylonitrile.

Furthermore, examples of butadiene include 1,2-butadiene and 1,3-butadiene.

The component of the outermost layer (C) constituting the impact modifier of the present invention is selected from the above monomer group so that the Tg of the outermost layer (C) itself is 0 ° C. or lower. Outermost layer (C)
In the composition ratio of the above-mentioned monomer, the acrylic acid alkyl ester is 0 to 100% by weight, the methacrylic acid alkyl ester is 0 to 40% by weight, and the aromatic vinyl compound is 0 to 40% by weight.
Vinyl cyanide compound 0-20% by weight, butadiene 0-1
It can be used in the range of 00% by weight. When the Tg of the outermost layer (C) itself exceeds 0 ° C., it is difficult to obtain the desired impact resistance improving effect. In addition, acrylic acid alkyl ester is preferable to butadiene in that atmospheric polymerization is possible.

The proportion of the outermost layer (C) in the total amount of the multi-layer graft copolymer is preferably 10 to 60% by weight, and if it is less than 10% by weight, the impact resistance improving effect is small, and 6
A proportion of more than 0% by weight is not preferable because the moldability when blending with PVC and molding becomes poor.

The components of the second layer (B) counted from the outermost layer (C) are selected from the above monomer group so that the Tg of the layer (B) itself is 60 ° C. or higher. The composition ratio of the monomer in the layer (B) is 0 to 100% by weight of methacrylic acid alkyl ester, 0 to 100% by weight of aromatic vinyl compound, 0 to 30% by weight of vinyl cyan compound, and 0 to 20% of acrylic acid alkyl ester. It can be used in the range of weight%. When the Tg of the layer (B) itself is less than 60 ° C., the multi-layered graft polymer particles are likely to aggregate and the impact resistance is poor. Layer (B)
When blending with PVC, alkyl methacrylic acid ester is preferable, and methyl methacrylate is particularly preferable. Although the fluidity is improved during blend molding with the aromatic vinyl compound PVC, compatibility is deteriorated and impact resistance is lowered when used in a large amount. A vinyl cyan compound is preferable because it promotes gelation at the time of blending with PVC, but if used in a large amount, it tends to be colored during molding and the processability deteriorates.

The proportion of the layer (B) in the total amount of the multilayer graft copolymer is preferably 20 to 60% by weight, and 20% by weight.
If it is less than the above range, the molding processability at the time of blending with PVC and molding is inferior, which is not preferable. On the other hand, if the proportion exceeds 60% by weight, the amount of the elastic material component in the whole multilayer graft copolymer is reduced, and the impact resistance improving effect is small, which is not preferable.

The diene-based elastic material (A) contains a rubber component which is a base material of the multi-layer graft copolymer, and the rubber component is 50% by weight or more of polybutadiene or butadiene and 50% by weight of another vinyl compound copolymerizable therewith. It is the following copolymer. Other vinyl compounds that can be copolymerized include styrene and acrylonitrile.

The proportion of the diene-based elastic material (A) in the total amount of the multi-layer graft copolymer is preferably 10 to 60% by weight, and the proportion of less than 10% by weight has a small effect of improving impact resistance. Further, if the proportion exceeds 60% by weight, not only the solidification of the emulsion polymer latex becomes difficult, but also the molding processability at the time of blending with PVC and molding is inferior, which is not preferable.

The polyfunctional crosslinking agent of the present invention not only facilitates the graft cross-linking in producing the impact modifier of the present invention, but also significantly improves the coagulability of the emulsion polymer latex. It is a thing. As the polyfunctional crosslinking agent, divinylbenzene, diacrylic acid ester or dimethacrylic acid ester which is an ester of polyhydric alcohol with acrylic acid or methacrylic acid, or triallyl cyanurate, triallyl isocyanurate, allyl acrylate, allyl methacrylate. , Diallyl itaconate, diallyl phthalate and the like. From the viewpoint of graft crossing property, a cross-linking agent having an allyl group is preferable.

The proportion of the polyfunctional crosslinking agent in each layer is 0.
~ 5% by weight. When it is used in an amount of more than 5% by weight, the diene-based elastic body (A) or layer (C) constituting the elastic body layer impairs the elastic properties too. Further, the layer (B) which is a resin layer is P
Since the compatibility with VC is deteriorated, the impact resistance improving effect is deteriorated in both cases, which is not preferable. The proportion of the polyfunctional crosslinking agent in each layer is 0.1 to 0.1 in consideration of the coagulability of the emulsion polymer latex during the production of the multilayer graft copolymer, and the impact resistance improving effect of the resulting multilayer graft copolymer.
A range of 3% by weight is preferred.

The multi-layered graft copolymer which is the impact resistance modifier of the present invention is preferably produced by a conventional emulsion polymerization method.

Examples of the emulsifier include anionic surfactants such as fatty acid salts, alkyl sulfate ester salts, alkylbenzene sulfonate salts, alkyl phosphate ester salts, dialkyl sulfo succinate salts, polyoxyethylene alkyl ethers and polyoxys. Nonionic surfactants such as ethylene fatty acid ester, sorbitan fatty acid ester and glycerin fatty acid ester, and cationic surfactants such as alkylamine salts can be used. These surfactants can be used alone or in combination. Further, depending on the kind of the emulsifier, when the pH of the polymerization system is on the alkaline side, an appropriate pH adjusting agent can be used in order to prevent the hydrolysis of the alkyl acrylate.

As the polymerization initiator, an ordinary inorganic initiator such as a persulfate, an organic peroxide, an azo compound or the like may be used alone, or the above compound and a sulfite, a hydrogen sulfite or a thiosulfate may be used. , A first metal salt, sodium formaldehyde sulfoxylate, etc. may be combined and used as a redox initiator. Preferred persulfates as the initiator are sodium persulfate, potassium persulfate, ammonium persulfate and the like, and the organic peroxide is t
-Butyl hydroperoxide, cumene hydroperoxide, benzoyl peroxide, lauroyl peroxide and the like.

A chain transfer agent may be used to control the molecular weight of the polymer, and an alkylmercaptan having 5 to 20 carbon atoms can be used.

Polymerization is carried out at a temperature above the decomposition temperature of the initiator,
Under ordinary emulsion polymerization conditions, at least the outermost layer (C), the second outermost layer (C) to the second layer (B), and the diene-based elastic body (A) may have the above-described structure. At this time, the polymerization in each of the steps can be carried out while adding the whole amount of each monomer or a mixture of the monomers at once, or continuously adding the whole amount or a part thereof. However, from the viewpoints of stability of polymerization, removal of heat of polymerization reaction, etc., it is preferable to carry out the polymerization while adding the whole amount or a part thereof.

The particle size of the multilayer graft copolymer is PVC
It greatly affects the impact strength of the resin composition. If the particle size is too small, the effect of improving impact strength is small, and it is preferable that the particle size is as large as possible without impairing the stability of the latex. The particle size of the graft copolymer is 0.15 to 0.40 μ
The range is good, and it can be adjusted with an appropriate type and amount of emulsifier, or can be adjusted with a thickening agent such as an acid or an inorganic salt in an appropriate polymerization stage.

When the multi-layered graft copolymer is recovered from the obtained latex, it can be recovered by salting out or acidifying and coagulating, filtering and washing and then recovering it in powder form, or by spray drying, freeze drying and the like. Further, JP-A-57-
It can also be recovered by the method of No. 187322.

The impact modifier of the present invention is a graft copolymer having the above-mentioned multi-layer structure, imparts high impact resistance and good processability to various thermoplastic resins, and is a molded product. The appearance is also good.

The proportion of the impact modifier of the present invention incorporated into the thermoplastic resin is 3 to 100 parts by weight of the thermoplastic resin.
It is 50 parts by weight. If it is less than 3 parts by weight, the impact resistance improving effect is small, and if it exceeds 50 parts by weight, the mechanical properties originally possessed by the thermoplastic resin are impaired, which is not preferable. Here, the thermoplastic resin is PV
C, a polycarbonate resin, a polyester resin, an acrylonitrile-styrene-based resin, a methyl methacrylate-styrene-based resin, and the like. As PVC, in addition to polyvinyl chloride, a vinyl chloride-based copolymer containing 70% by weight or more of vinyl chloride can be used. Monomers copolymerizable with vinyl chloride include ethylene, propylene, vinyl bromide,
Vinylidene chloride, vinyl acetate, acrylic acid ester, methacrylic acid ester and the like are used.

The impact modifier of the present invention and the thermoplastic resin are preferably mixed in a powder form, for example, by a ribbon blender, a Henschel mixer, etc., and a known kneader,
For example, it is molded by a mixing roll, a Banbury mixer, an extruder, an injection molding machine and the like. When blending, known stabilizers, plasticizers, lubricants, colorants and the like may be added as necessary.

[0032]

The present invention will be described in detail with reference to the following examples. In Examples and Comparative Examples, "part" and "%" mean "part by weight" and "% by weight", respectively. Also,
The Tg of the copolymer in each of the Examples and Comparative Examples is obtained from the Fox equation.

Example 1 (a) Production of Rubber Elastic Body (A) A rubber elastic body (A) was synthesized according to the following composition. 1,3-Butadiene 75 parts Styrene 25〃 Diisopropylbenzene hydroperoxide 0.2〃 Sodium pyrophosphate 0.5〃 Ferrous sulfate 0.01〃 Dextrose 1.0〃 Potassium oleate 0.5〃 Water 200〃 The mixture having the above composition was polymerized in a pressure autoclave at 50 ° C. The polymerization was completed in 15 hours. The average particle size of the obtained rubber was 0.16 μ.

(B) Production of Multilayer Graft Copolymer 30 parts of the rubber latex obtained as in the above (a) (as polymer solids) was added with 0.6 part of semi-cured tallow potassium soap,
A solution prepared by dissolving 0.2 parts of sodium formaldehyde sulfoxylate in 120 parts of water was added, and the mixture was stirred while stirring to 70
The temperature was raised to ° C. The temperature of this latex was maintained at 70 ° C., 39.8 parts of methyl methacrylate, 0.2 part of triallyl isocyanurate, 0.1 part of cumene hydroperoxide.
A mixture of 5 parts was added dropwise over 2 hours and 30 minutes, and after the completion of the addition, the mixture was kept for 1 hour to complete the first stage graft polymerization. The polymerization rate was 99.8%.

To the obtained polymer latex, 0.3 part of semi-cured tallow potassium soap and 0.2 part of sodium formaldehyde sulfoxylate dissolved in 20 parts of water were added, and 29.8 parts of n-butyl acrylate. , Triallyl isocyanurate 0.2 part, cumene hydroperoxide 0.
The mixture consisting of 15 parts was added dropwise over 2 hours while maintaining the temperature at 70 ° C., and after completion of the addition, the mixture was maintained for 1 hour to complete the polymerization. The polymerization rate was 99.6%, and the particle diameter of the final graft copolymer was 0.21μ.

2,6-di-tert-butyl-p-cresol 1.0 was added as a stabilizer to the graft copolymer latex.
And 0.5 part of dilauryl thiodipropionate were added, coagulated with a 1% sulfuric acid aqueous solution, washed, dehydrated and dried to obtain a white powder resin (Example 1-1). Furthermore (A),
Various proportions of the respective components (B) and (C) were changed to obtain a multi-layer graft copolymer by the same polymerization formulation as above. Table 2
Shown in.

(C) Production of compounding composition with vinyl chloride resin 10 parts of the graft copolymer obtained by the above (b) and 90 parts of vinyl chloride resin having an average degree of polymerization of 700 are added to 100 parts in total of tribasic sulfuric acid. Lead 2.0 parts, dibasic lead stearate 0.
3 parts, 2.0 parts of lead stearate and 0.3 part of stearic acid were added and the temperature was raised to 115 ° C. in a Hensiel mixer to obtain a uniform mixture. 30m of this vinyl chloride composition
Square rod molding was performed under the conditions shown in Table 1 with an mφ single screw extruder.

[0038]

[Table 1]

The compounding and molding conditions are such that no kneading is necessary. The impact strength of the molded product is ASTMD-2
According to No. 56, Izod impact test with U-notch was performed. The results of these measurements are also shown in Table 2.

Comparative Example 1 60 parts (as polymer solids) of the rubber latex produced in (a) of Example 1 was added with 0.6 part of semi-cured tallow potassium soap.
A solution prepared by dissolving 0.2 parts of sodium formaldehyde sulfoxylate in 70 parts of water was added, and the mixture was stirred at 70 ° C.
The temperature was raised to. The temperature of this latex was maintained at 70 ° C., 39.8 parts of methyl methacrylate, 0.2 part of triallyl isocyanurate, 0.1 part of cumene hydroperoxide.
A mixture of 5 parts was added dropwise over 2 hours and 30 minutes, and after completion of the addition, the mixture was kept for 1 hour to complete the graft polymerization. The polymerization rate was 99.8%, and the particle size of the final graft copolymer was 0.20 μm. The graft copolymer was recovered from this polymer latex in the same manner as in Example 1. A composition prepared by blending this graft copolymer with the same formulation as in (c) of Example 1 was subjected to square bar molding under the same conditions, and the same Izod impact test with U-notch was performed. The measurement results are also shown in Table 2.

Comparative Example 2 30 parts (as polymer solids) of the rubber latex produced in (a) of Example 1 was added with 0.3 part of semi-cured tallow potassium soap.
A solution prepared by dissolving 0.2 parts of sodium formaldehyde sulfoxylate in 120 parts of water was added, and 29.8 parts of n-butyl acrylate and 0.2 parts of triallyl isocyanurate.
And 0.15 parts of cumene hydroperoxide were added dropwise over 2 hours while maintaining the temperature at 70 ° C. After completion of the dropping, the polymerization was completed by holding for 1 hour.
The polymerization rate was 99.5%.

To this polymer latex, 0.6 part of semi-cured potassium tallow soap and 0.2 part of sodium formaldehyde sulfoxylate dissolved in 10 parts of water were added, and 39.8 parts of methyl methacrylate and triallyl isocyanate were added. A mixture of 0.2 part of nurate and 0.15 part of cumene hydroperoxide was added dropwise over 2 hours and 30 minutes, and after the completion of the addition, the mixture was maintained for 1 hour to complete the polymerization. Polymerization rate is 9
The average particle size of the graft copolymer obtained at 9.8% was 0.21 μm. The graft copolymer was recovered from this polymer latex in the same manner as in Example 1. A composition prepared by blending this graft copolymer with the same formulation as in (c) of Example 1 was subjected to square bar molding under the same conditions, and the same Izod impact test with U-notch was performed.
The measurement results are also shown in Table 2.

The abbreviations in Table 2 are as follows, and the same applies to the subsequent cases. Bd: 1,3-Butadiene St: Styrene MMA: Methyl methacrylate BA: n-Butyl acrylate TAIC: Triallyl isocyanurate In Table 2, all the ratios of Bd to St of the diene elastic body (A) component are Bd. / St = 75/25 (parts). From the above results, it is understood that the present invention has a great effect of improving the impact strength as compared with Comparative Examples 1 and 2.

[0044]

[Table 2]

Example 2 A mixture of 27.9 parts of styrene and 0.1 part of allyl methacrylate as the component (B) in the proportions shown in Table 3 as the component (A), 11.9 parts of methyl methacrylate and methacrylic acid. Except that a mixture of 0.1 part of allyl acid is polymerized in two steps and a mixture of 29.8 parts of 2-ethylhexyl acrylate and 0.2 part of allyl methacrylate is further polymerized as the component (C). Polymerization was carried out in the same manner as in (a) and (b) of Example 1. The impact resistance of the vinyl chloride composition obtained by operating the graft copolymer thus obtained in the same manner as in (c) of Example 1 is shown in Table 3.
This resin composition exhibits good transparency because the refractive index of the graft copolymer is the same as that of PVC. Similarly, the impact resistance improving effects of the components (A), (B), and (C) were changed in Examples 2-2 and 2-3 and Comparative Example 3.
4 is also shown in Table 3.

The abbreviations in Table 3 are as follows. The component (B) is polymerized in two stages. AMA: Allyl methacrylate 2EHA: 2-Ethylhexyl acrylate In Table 3, Examples 2-1 and 2-2 and Comparative Example 4 were used.
The ratio of Bd to St of the diene-based elastic body (A) component is Bd / St = 75/25 (part), and the ratio of Bd to St of the diene-based elastic body (A) component of Example 2-3 is The ratio is Bd / St = 60/40 (part), that of Comparative Example 3 is B
d / St = 30/70 (parts). From the above results, it can be seen that the component (A) or the component (C) having a high Tg has a small impact resistance improving effect.

[0047]

[Table 3]

Example 3 A butadiene-styrene copolymer (A) was synthesized with the same formulation as in (a) of Example 1. Obtained rubber latex 30
Part (as polymer solids) was subjected to graft polymerization in the same manner as in (b) of Example 1. However, as the component (B), 34.8 parts of methyl methacrylate, 5 parts of acrylonitrile,
A mixture of 0.2 parts of triallyl isocyanurate was polymerized. Further, as the component (C), acrylic acid n-
Octyl 29.8 parts, triallyl isocyanurate 0.
A mixture of 2 parts was polymerized.

The impact resistance improving effect of the vinyl chloride composition obtained by operating the obtained graft copolymer in the same manner as in (c) of Example 1 is shown in Table 4. In the same manner, the impact resistance improving effects of the graft copolymers in which the amounts of the cross-linking agents of the components (B) and (C) are changed are also shown in Table 4 as Example 3-2 and Comparative Example 5.

The abbreviations in Table 4 are as follows. OA: n-octyl acrylate AN: acrylonitrile All the ratios of Bd and St of the diene elastic body (A) component in Table 4 are Bd / St = 75/25 (parts). From the above results, it can be seen that the impact resistance improving effect is small when a large amount of the cross-linking agent of the components (B) and (C) is used.

[0051]

[Table 4]

Claims (3)

[Claims] 1. A copolymer containing 100 parts by weight of a thermoplastic resin, 0 to 5% by weight of a cross-linking agent, and 50% by weight or more of polybutadiene or butadiene and 50% by weight or less of another vinyl compound copolymerizable therewith. A multi-layered graft copolymer in which at least two graft layers are graft-polymerized to the butadiene-based elastic body (A), which comprises: an acrylic acid alkyl ester, a methacrylic acid alkyl ester, an aromatic vinyl compound, vinyl Each graft layer is composed of a monomer selected from the group of monomers consisting of a cyan compound and butadiene, and each graft layer contains a crosslinking agent in an amount of 0 to
The glass transition temperature of the polymer constituting 5% by weight and constituting the outermost layer (C) is 0 ° C. or lower, and the glass transition temperature of the polymer constituting the second layer (B) from the outermost layer (C) is 60 ° C. A thermoplastic resin composition comprising 3 to 50 parts by weight of an impact modifier, which is characterized in that it is excellent in impact resistance and moldability. 2. The impact-modifying agent according to claim 1, wherein the butadiene-based elastic material (A) accounts for 10 to 60% by weight in the multilayer graft copolymer, and the outermost layer (C) is a single amount. 95-100% by weight of at least one monomer selected so that the glass transition temperature of the polymer constituting the layer (C) is 0 ° C. or lower, and 0-5% by weight of a crosslinking agent. And a ratio of 1 to 1 in the multilayer graft copolymer.
0 to 60% by weight, second layer from outermost layer (C) (B)
However, 95-100% by weight of at least one monomer selected from the monomer group so that the glass transition temperature of the polymer constituting the layer (B) is 60 ° C. or more, and the crosslinking agent 0- The thermoplastic resin composition according to claim 1, which is a polymer composed of 5% by weight and accounts for 20 to 60% by weight in the multilayer graft copolymer. 3. The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin mixed with the impact modifier according to claim 1 is a vinyl chloride resin.