JPS6032849A - Agent for improving impact resistance of thermoplastic resin, and thermoplastic resin containing the same - Google Patents

Abstract

PURPOSE:To provide the titled agent capable of imparting a PVC resin with high impact resistance and moldability, having excellent weather resistance, and composed of a multi-layer graft copolymer containing a monomer such as alkyl acrylate as a component and having a specific three-layered structure. CONSTITUTION:An improving agent composed of a multi-layered graft copolymer composed of the monomers selected from alkyl acrylate, alkyl methacrylate, aromatic vinyl compound, and vinyl cyanide compound and having at least 3 layers wherein the grass transition temperature of the polymer constituting the outermost layer (the first layer) is <=0 deg.C, that of the polymer constituting the next layer (the second layer) is >=60 deg.C and that of the polymer constituting the innermost layer (the third layer) is <=0 deg.C. Each layer contains 0-5wt% polyfunctional crosslinking agent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an impact modifier for thermoplastic resins that can impart high impact resistance and good moldability, and also has good weather resistance.

Thermoplastic resin, especially vinyl chloride resin (PVC)
It is abbreviated as ) is widely used as a general-purpose resin, but its mechanical properties are not necessarily satisfactory.

That is, PVC has poor impact strength, particularly notched impact strength, and various modifiers have been proposed for the purpose of improving this impact strength.

Effective methods for the inner layer of these proposals include so-called MBS resin, which is obtained by graft polymerizing a methacrylic acid alkyl ester and an aromatic vinyl compound onto a conjugated diene elastomer, and ABS resin, which is obtained by graft polymerizing a vinyl cyanide compound and an aromatic vinyl compound onto a conjugated diene elastomer. A method of blending PvC with PvC is known. However, since these MBS resins and ABS resins contain multiple double bonds in the main chain of the elastomer component, if they are used outdoors for a long time, they tend to cause chalking and a decrease in impact strength, making them unsuitable for outdoor use. do not have.

Furthermore, a method using an elastic body in which saturated acrylic acid alkyl ester is partially replaced with conjugated die/die has also been proposed. In this case, it shows a high impact strength improvement effect, but the weather resistance is M
Although it is not as bad as BS resin or ABS resin, it still has the disadvantage of being bad.

Furthermore, there are various resin compositions with good weather resistance that use saturated polyacrylic acid alkyl ester as an elastic body and blend copolymers obtained by graft polymerization of methacrylic acid alkyl ester, aromatic vinyl compound, pre-vinyl cyanide, etc. with PVC. Proposed.

However, these copolymers show a considerable impact strength improvement effect under the kneading conditions (hereinafter referred to as high-lubricity conditions), although they are not as effective as MBS resin, but they require a large amount of lubricant. If there was.

Alternatively, under conditions where cross-contact does not occur (hereinafter referred to as high-slip conditions), such as when processed at a relatively low temperature, there is almost no impact strength improvement effect.

The present inventors conducted extensive studies in view of the current situation, and found that uniformly dispersing a multilayer graft copolymer using an acrylic acid alkyl ester elastomer in PvC significantly (contributes) to the development of impact strength. Even more surprisingly, the glass transition temperature of the outermost layer (abbreviated as daytime T/ ) is 0℃ or less, the outermost layer or r-) the second layer has a Tf of 60℃ or more, and the third layer from the outermost layer has a Tf of 0℃ or less (both are multilayer structures consisting of three layers). The multilayer graft copolymer having the above properties is more likely to melt quickly even under high lubricity conditions and low shear stress. Moreover, such a PvC resin composition can exhibit high impact strength in a wide range of moldability and has good processability.

The present invention was achieved by discovering that it has excellent surface gloss and also good weather resistance.

That is, the gist of the present invention is that the outermost layer (Al is The T of the constituent polymer is 0°C or less, the TI of the polymer constituting the outermost layer (the second layer from AJ (El) is 60°C or more, the third layer from the outermost layer (A) (constituting C1) Layers (A), (B), and (C) in which the Tt of the polymer is 0° C. or less (all have a multilayer structure consisting of three layers, and in each layer, no polyfunctional crosslinking agent is added to each layer) An impact resistance modifier for thermoplastic resins having good weather resistance and comprising a multilayer graft copolymer containing ~5 i% by weight.

It is essential that the impact modifier of the present invention has a multilayer structure of three or more layers obtained by polymerization in at least three stages, and the 14th layer counting from the outermost layer is made of the homopolymer ( Even if it is a four-layer graft copolymer made of a polymer whose temperature is 60°C or higher, the 15th layer counting from the outermost layer is made of a polymer whose Tt is 7!l''-0°C or lower than that of the homopolymer. When using a multilayer graft copolymer such as a five-layer graft copolymer, the effect of improving impact resistance is similarly exhibited even in such cases.

The monomer group constituting the impact modifier of the present invention is acrylic acid alkyl ester, methacrylic acid alkyl ester,
It is composed of an aromatic vinyl compound and a vinyl cyanide compound.

As the acrylic acid alkyl ester, those having an alkyl group of 2 to 10 carbon atoms are preferred, such as ethyl acrylate and propyl acrylate.

n-butyl acrylate, inbutyl acrylate.

Examples include hexyl acrylate, octyl acrylate, and 2-ethyl-hexyl acrylate.

The methacrylic acid alkyl ester preferably has an alkyl group having 1 to 4 carbon atoms, such as methyl methacrylate, ethyl methacrylate, propyl methacrylate,
Inglovir methacrylate, n-butyl methacrylate,
Inbutyl methacrylate and tert-butyl methacrylate can be traced. Considering compatibility with PVC, methyl methacrylate is particularly preferred.

Also, styrene is an aromatic vinyl compound.

α-substituted styrene/, nuclear substituted ethyl 7 j6 and its? A
6+ e.g. α-methylstyrene, chlorstyrene/,
Examples include vinyltoluene.

Furthermore, as vinyl shea 7 compounds, acrylonitrile,
Examples include methacrylonitrile.

The outermost layer constituting the impact modifier of the present invention (the Al component is selected from the above monomer group so that the TP of the outermost layer itself is 71''-0°C or less.The outermost layer tAl The composition ratio of the monomers in the acrylic acid alkyl ester is 60%.
~100 heavy weight %, methoxylic acid alkyl ester 0-4
It can be used in a range of 0% by weight, 0 to 40% by weight of the aromatic vinyl compound, and θ to 20% by weight of the vinyl cyanide compound.

If the TI of the outermost CAl layer itself exceeds 0°C, the final modifier can be blended with PvC and molded (
If the melting of the N layer portion is too slow, the desired effect of improving impact resistance cannot be obtained sufficiently.

The proportion of the outermost layer (Al) in the total amount of the multilayer graft copolymer is preferably 10 to 50% by weight. If the proportion is less than 10% by weight, the effect of improving impact resistance is small, and if the proportion exceeds 50% by weight, it is blended with PVC. This is not preferable because it results in poor molding processability when molding.

In addition, the outermost layer (At or the second layer (Bl component is in the first layer (
The monomers are selected from the above monomer group so that the TJE of Hj itself is 60°C or higher. said monomer set g in layer fBl
tl1 is a methacrylic acid alkyl ester O to 100% by weight, an aromatic vinyl compound θ to 100% by weight, and a vinyl cyanide compound 0 to 30% by weight.

Acrylic acid alkyl ester can be used in a range of 0 to 20% by weight. If the TI of the layer fBl itself is less than 60°C, it is difficult to obtain a multilayer graft polymer as a good powder. When blending with PVC, methacrylic acid alkyl esters are preferred, and methyl methacrylate is particularly preferred.Aromatic vinyl compounds improve fluidity when blended with PVC; If used in a large amount, the compatibility deteriorates and the impact resistance decreases.Furthermore, vinyl cyanide compounds are preferable because they promote gelation during friending with PvC, but if used in large amounts, they tend to cause discoloration during molding. (As a result, the processability deteriorates.

The proportion of the layer CB+ in the total amount of the multilayer graft copolymer is preferably 20 to 60% by weight, and a proportion of less than 200% by weight is not preferable because the molding processability when blended with PVC and molded is poor. In addition, if the ratio exceeds 600% by weight, the amount of the elastic component in the entire multilayer graft copolymer decreases, and the effect of improving impact resistance is small, which is undesirable (ゝ0 Furthermore, the third layer IC from the outermost layer (A)) The ingredients are.

The monomers are selected from the above monomer group so that the T/ of the layer (C) itself is 0° C. or less. The composition ratio of the monomer in layer (C) is 60 to 100% of alkyl acrylate;
Methacrylic acid alkyl ester - 0-40 weight ratio, aromatic vinyl compound 0-40M weight ratio, vinyl shea/compound 0
It can be used within the range of 20. T of layer (C) itself! When the temperature exceeds 0°C, the elastic properties of the layer (C1 itself) are impaired.

The desired effect of improving impact resistance cannot be obtained.

fi (The proportion of CJ in the total amount of the multilayer graft copolymer is preferably 10 to 60% by weight, and if the proportion is less than 100% by weight, the effect of improving impact resistance is small.

Further, if the proportion exceeds 600% by weight, the molding processability when blending with PvC and molding becomes poor, which is not preferable.

The polyfunctional crosslinking agent in the third aspect of the present invention not only facilitates the graft paternal bonding when producing the impact modifier of the present invention (but also significantly improves the coagulation properties of the emulsion polymer latex). It is something to do.

Divinylbenzene is a polyfunctional crosslinking agent.

Diacrylic acid ester or dimethacrylic acid ester, which is an ester of acrylic acid or methacrylic acid and a polyhydric alcohol, or triallyl cyanurate, triallyl incyanurate.

Examples include allyl acrylate, allyl methacrylate, diallyl itaconate, diallyl phthalate, and the like. Considering R-graft cross-reactivity, a crosslinking agent having an allyl group is preferable.

The proportion of the polyfunctional crosslinking agent in each layer is 0 to 5% by weight. If it is used in an amount exceeding 5% by weight, the elastic properties of the outermost layer (A) or the layer (CJ) will deteriorate too much. Also, the compatibility of the resin layer (B) with PVC will deteriorate. Therefore, both are undesirable because the effect of improving impact resistance decreases.

The proportion of the multifunctional crosslinking agent in each layer should be 0.00000000000000000000000000000000000000000', taking into account the coagulability of the emulsion polymer latex during production of the multilayer graft copolymer and the effect of several microns on the impact resistance of the resulting multilayer graft copolymer. A weight range of 1 to 3 weights is preferred.

The multilayer graft copolymer that is the impact modifier of the present invention is preferably produced by a conventional emulsion polymerization method.

As an emulsifier. Fatty acid salt, alkyl sulfate salt,
Alkylbenzene sulfonate.

Anionic surfactants such as alkyl acid ester salts and dialkyl sulfosuccinates; nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, nlupita fatty acid esters, and glycerin fatty acid esters; Additionally, cationic surfactants such as alkylamine salts can be used. These surfactants can be used alone or in combination. Also, when the pH of the bipolymerization system becomes alkaline depending on the type of emulsifier.

Appropriate pH regulators may also be used to prevent hydrolysis of the acrylic acid alkyl ester.

As a polymerization initiator, an ordinary inorganic initiator such as a persulfate, an organic peroxide, an azo compound, etc. may be used alone, or the above compound and a sulfite, hydrogen sulfite, thiosulfate, etc. may be used. It can also be used as a redox initiator in combination with a first metal salt, sodium formaldehyde sulfoxylate, etc. Preferred persulfates as initiators include persulfate, potassium persulfate, ammonium persulfate, etc., and examples of organic peroxides include t-butylpitropaloxide.

Cumene hydroperoxide, benzoyl peroxide.

lauroyl peroxide, etc.

A chain transfer agent may be used to adjust the molecular 1 degree of the polymer, and alkyl mercaptans having 5 to 20 carbon atoms can be used.

Polymerization is carried out at a temperature above the decomposition temperature of the initiator under normal emulsion polymerization conditions, at least the outermost layer (A) and the outermost 7F'fCA.
It can be carried out so that the second layer (Bl) and the third layer (C) from the outermost layer (Al) have the structure described above.In this case, for each stage of polymerization, each monomer The whole amount or a mixture of monomers can be added all at once, or all or part of the mixture can be added continuously.However, from the viewpoint of stability of polymerization, removal of the heat of the polymerization reaction, etc. It is preferable to carry out the polymerization while adding .

The particle size of the multimodal graft copolymer greatly influences the impact strength of the PVC resin composition. If the particle size is too small, the effect of improving impact strength will be small, so it is preferable that the particle size be as large as possible without impairing the stability of the latex. The particle size of the kraft copolymer is preferably in the range of 0.15 to 0.40μ (it can be adjusted by adjusting the type and amount of an appropriate emulsifier, or by using a thickening agent such as an acid or an inorganic salt at an appropriate polymerization step). It can also be adjusted.

The obtained latex of the multilayer graft copolymer is usually salted out or acidified and coagulated and collected in a powder form by washing with water, or it can be collected in a powder form by spray drying, freeze drying, etc. .

The impact resistance modifier of the present invention is a kraft copolymer having a multilayer structure as described above, and it imparts high impact resistance and good processability to various thermoplastic resins, and also improves the weather resistance of molded products. It is to be in good condition.

The proportion of the impact modifier of the present invention blended into the thermoplastic resin is 3 to 50 parts by weight per 100 parts by weight of the thermoplastic resin. If the blending ratio is less than 3M parts, the effect of improving impact resistance will be small (and if it exceeds 50 parts by weight, the mechanical properties inherent to the thermoplastic resin will be impaired, so both are not preferred. PVC includes PVC, polycarbonate resin, polyester resin, acrylonitrile-ethylene resin, methyl methacrylate-ethylene resin, etc. PVC includes polyvinyl chloride, and vinyl chloride copolymer containing vinyl chloride 0M or more. Examples of monomers copolymerized with vinyl chloride include ethylene, vinyl bromide, vinylidene chloride, vinyl acetate, acrylic ester, and methacrylic ester.

The impact modifier of the present invention and the thermoplastic resin are preferably blended in powder form using a ribbon printer, a Henschel mixer, etc., and a known mixer such as a mixing roll, a Banbury mixer, an extruder, etc. It is molded using an injection molding machine, etc. In addition, when compounding, known stabilizers, plasticizers, lubricants, colorants, etc. may be added as necessary, and the temperature may be maintained at ℃.

The present invention will be specifically explained below using Examples.

In the examples, "parts" 2 and 1%" are "parts by weight" and "1%," respectively.
% by weight.

Example 1 (Production of multilayer graft copolymer) 190 parts of nitrogen-substituted io/exchanged water was placed in a reaction vessel,
1.2 parts of semi-hardened beef tallow fatty acid fabric.

Dissolve 0.6 parts of persulfuric acid and, while maintaining it at 70°C, add n-butylene/l' acrylic acid as a 7FHCI component.
19.85nL) IJ allyl in cyanurate 0.
A mixture consisting of 15 parts was added dropwise over the course of 1 hour. After the dropwise addition was completed, the temperature was kept at the same temperature for 1 hour to complete double polymerization. The polymerization rate was 99.0.

This polymer latex contained 49.7 parts of methyl methacrylate as component i (B) and 0 parts of triallyl in cyanurate.
．． 3 parts and the mixture was heated to 70°C for 2 hours.
Add drops while keeping at ℃, hold for 1 hour after adding 2 drops
Polymerization was completed. The polymerization rate was 99.5%.

0.2 parts of potassium persulfate dissolved in 10 parts of water was added to the obtained (1) combined latex to form one layer (A + acid components: 29.8 parts of n-butyl acrylate, 0.0 parts of triallylinocyanurate). Two parts of the mixture was added dropwise over 90 minutes while maintaining the temperature at 70°C, and after the completion of one drop, the polymerization was completed by holding for 1 hour.The polymerization rate was 99.3%, and the graft copolymer was The average particle diameter was 0.25μ.

The obtained multilayer graft copolymer latex was added to an aqueous sulfuric acid solution, solidified by acid precipitation, washed, dehydrated, and dried, and the graft copolymer was collected in powder form at °C (Example 1-1).
).

Further, the composition ratio of layer (C) and layer (B) per rotation was variously changed to obtain a multilayer graft copolymer obtained using the same polymerization recipe as described above. These are shown in Table 1.
) and 87 parts of vinyl chloride resin with an average degree of polymerization of 700, 2.5 parts of dibutyltin malate and 0.8 parts of butyl stearate.
11 parts, 0.7 parts of lubricant was added in a Henschel mixer.
The temperature was raised to 5°C to obtain a homogeneous mixture. This vinyl chloride resin composition was kneaded for 3 minutes using a mixing roll adjusted to 175°C, and the resulting sheet was heated and pressed to prepare a test piece, and its impact strength was measured. Impact strength is ASTM
-D-256, a notched Izot impact test was conducted. The blending conditions and molding conditions of this vinyl chloride resin composition are set to be low slip conditions.

In addition, 13 parts of each multilayer graft copolymer obtained by the above (IL) and 87 parts of vinyl chloride resin with an average degree of polymerization of 700 were added to a total of 100 parts, 2.0 parts of tribasic lead sulfate, and 2.0 parts of dibasic stearic acid/lead acid. 0.3 copies.

2.0 parts of lead stearate and 0.3 parts of stearic acid were added, and the mixture was heated to 115° C. in a Henschel mixer to obtain a homogeneous mixture. This vinyl chloride composition was formed into a square bar using a 30 mm diameter single screw extruder under the following conditions.

The impact strength of the molded article was measured in accordance with ASTM-D-256, except that a specimen with a U-notch of 2 cm deep was used. The blending conditions and molding conditions for this vinyl chloride resin composition are set to high lubricity conditions.

These measurement results are also shown in Table 1.

In addition, fd Table 1 also shows the impact strength of the vinyl chloride resin self-sprouting under high-slip conditions and low-slip conditions.

Comparative Example 1 190 parts of nitrogen-substituted ion-exchanged water was placed in a reaction vessel,
1.2 parts of semi-hardened beef tallow fatty acid soap and 0.4 parts of potassium persulfate were dissolved, and while maintaining the mixture at 70°C, a mixture consisting of 59.7 parts of n-butyl acrylate and 0.3 parts of triallylin cyanurate was dissolved. The mixture was added dropwise over 3 hours. After the dropwise addition was completed, the temperature was kept at the same temperature for 1 hour to complete the polymerization. The polymerization rate was 99.5%.

To this polymer latex was added 0.2 parts of potassium persulfate dissolved in 10 parts of water, and 2 parts of a mixture consisting of 39.8 parts of methyl methacrylate and 0.2 parts of triallyl in cyanurate was added.
The mixture was added dropwise while maintaining the temperature at 70°C over a period of time. After the dropwise addition was completed, the temperature was kept at the same temperature for 1 hour to complete the third batch. The polymerization rate was 99.7%. The average particle diameter of the graft polymer was 0.23μ.

A graft copolymer was recovered from this graft polymer latex in the same manner as in Example 1.

A composition in which this graft copolymer was blended according to the same formulation as in Example 1 (bl) was measured for impact strength under the same high-slip conditions and low-slip conditions.

These results are shown in Table 2.

Comparative Example 2 In Comparative Example 1, the amount of potassium persulfate in the first stage was changed to 0.2 parts, and a mixture consisting of methyl methacrylate 39.1B and ) realyl isocyanurate 0.2 parts was similarly polymerized.

Furthermore, 0.4 part of potassium persulfate dissolved in 10 parts of water was added to this polymer latex, and 59.9 parts of n-butyl acrylate was added.
Polymerization of a mixture consisting of 7 parts and 0.3 parts of triallylisocyanuride was completed in the same manner as in Comparative Example 1, and the graft copolymer was recovered.

A composition in which this graft copolymer was blended according to the same formulation as in Example 1 (bl) was measured for impact strength under the same high-slip conditions and low-slip conditions.

These results are also shown in Table 2.

Table 12 As is clear from the results in Table 2, it can be seen that the impact resistance modifier of the present invention exhibits a high impact resistance improvement effect particularly under high slip conditions.

Table 2 Table 11 The abbreviations in Table 2 are as follows, and the same applies to the following cases.

BA n-butyl nyacrylate MMA: Methyl methacrylate TAIC: hlylyl in cyanurate In Table 19 and Table 2, T/ is derived from the formula of Fax.

Example 2. Comparative Examples 3 to 4 Layer FC + 1 layer of component (exactly the same as Example 1 except that the Bl component and the layer (A) component mono-critical O 6 and the type and number of crosslinking agents were changed as shown in Table 3) The impact strength of the multilayer graft copolymer obtained by the above procedure was measured in the same manner as in Example 1 (bJ).

These results are shown in Table 3.

The abbreviations in Table 3 are as follows, and the same applies to the following cases.

2EHA: 2 Ethylhegysyl acrylate St
: To styrene N : Acrylonitrile AMA : Allyl methacrylate As can be seen from Comparative Examples 3 and 4, it is found that the effect of improving impact resistance is small when the M (C) component or the layer (A) component has a high Tf.

Example 3 180 parts of nitrogen-substituted ionic water was placed in a reaction vessel,
Lauroilbe/Zensle 7 on at υ'7 A 1.
4 parts, sodium formaldehyde sulfoxylate) 0
7FJ (C
) A mixture consisting of 29.8 parts of n-octyl acrylate, 0.2 parts of triallyl cyanurate, and 0.15 parts of cumene hydroperoxide was added dropwise over 1 hour and 30 minutes. After the dropwise addition was completed, the temperature was kept at the same temperature for 1 hour to complete the polymerization.

This polymer latex was coated with a layer (It) of a mixture consisting of 34.7 parts of methyl methacrylate, 5 parts of acrylonitrile, 3*L cumene hydroperoxide, and 0.2 parts of 3*L cumene hydroperoxide. The mixture was added dropwise over 2 hours while being kept at ℃.

After the dropwise addition was completed, the mixture was maintained for 1 hour to complete 9 polymerizations.

To the obtained polymer latex, 0.6 parts of sodium lauroylbenzenesulfonate and 0.15 parts of sodium formaldehyde sulfoxylate were dissolved in 20 parts of water, and 29 parts of n-octyl acrylate were added as the first layer (A) component.
．． A mixture consisting of 8 parts of triallyl cyanurate, 0.2 parts of cumene hydroperoxide, and 0.15 parts of cumene hydroperoxide was heated to 70
The mixture was added dropwise over 1 hour and 30 minutes while maintaining the temperature at °C. After the dropwise addition was completed, the temperature was kept at the same temperature for 1 hour to complete 9 polymerizations. The average particle diameter of the obtained graft copolymer was 0.22
It was μ.

Example 1 from the obtained multilayer graft copolymer latex
The graft copolymer was recovered in the same manner as (al), and a PVC resin composition was obtained in the same manner as (bl) of Example 1. The impact strength of this was measured in the same manner as (bl) of Example 1. These results are shown in Table 4.

Furthermore, Table 4 also shows the results when the composition ratio between the nine layers (C) and the nine layers (B) was changed.

The abbreviations in Table 4 are as follows.

OA n-octyl niacrylate TAC: ) Realyl cyanurate Not shown in Table 4 5 K+ If the amount of crosslinking agent in each component is large,
It can be seen that the effect of improving impact resistance is slightly better.

Example 4 Methyl methacrylate-butadiene-styrene resin (MB 54tJ resin), a commercially available PvC resin modifier
and chlorinated polyethylene (clpE) in Example 1 (
The high lubricity condition of Example 1 (bl) using the PVC resin composition produced under the high lubricity conditions of b) and the multilayer graft copolymer obtained in Example 1 (,) of the present invention The weather resistance of the PVC resin composition is shown in Table 5. The weather resistance is shown by the Izot impact strength and the degree of coloring after accelerated exposure treatment using a Weatherometer (Toyo Rika Membrane Model WE-1).

Table 5 The display of the degree of coloring in Table 5 is as follows.

◯: Almost no coloring, good quality.

Δ: Slightly colored, not very desirable.

×: Colored and defective.

From the results of bag 5, the modifier according to the present invention is commercially available MBS, C
It can be seen that the weather resistance (initial I/Pact retention rate, color banding property) is very good compared to A'PE.

Claims (1)

[Claims] 1. Consisting of a monomer selected from the monomer group consisting of an acrylic acid alkyl ester, a methacrylic acid alkyl ester, an aromatic vinyl compound, and a vinyl cyanide compound, and the outermost layer (constituting the AI) The glass transition temperature of the polymer is 0°C or lower.The glass transition temperature of the polymer constituting the outermost layer (Al or second layer (B) is 60°C or higher, the outermost layer (A) fJ・5
The third layer (WIcA in which the glass transition temperature of the polymer constituting Cl is 0 ° C. or lower), with a small amount of (B) and (C) (both have a multilayer structure consisting of a three-layer structure. An impact resistance modifier for thermoplastic resins with good weather resistance consisting of a multilayer graft copolymer containing 0 to 5% by weight of a polyfunctional crosslinking agent. 2. Outermost layer (AJ is a monomer group A layer (95 to 100 parts by weight of at least one monomer selected so that the glass transition temperature of the polymer constituting Al is 0°C or less and 0 to 5 parts by weight of a polyfunctional crosslinking agent, etc.) )7.c polymer,
, and the proportion in the multilayer graft copolymer is 10 to 5.
0% by weight. The outermost layer (the second layer from N (131) is the layer from the monomer group (the glass transition temperature of the polymer constituting Bl is 60 ° C.
A small amount (also a type of monomer 95
~100% by weight and 0-5% by weight of a polyfunctional crosslinker. and the proportion in the multilayer graft copolymer is 20 to 60.
% by weight, the outermost layer (the third layer (C) from N) contains at least one monomer selected from the monomer group so that the glass transition temperature of the polymer constituting the layer (C) is 0°C or less. A polymer consisting of 95 to 100 weight percent of a monomer and 0 to 5 weight percent of a polyfunctional crosslinking agent, and the proportion thereof in the multilayer graft copolymer is 10 to 60 percent by weight. An impact resistance modifier for thermoplastic resins as set forth in claim 1. 3. Consisting of 100 parts by weight of a thermoplastic resin and 3 to 50 parts by weight of the modifier as set forth in claim 1. Thermoplastic resin composition with good weather resistance, impact resistance and moldability. 4. The thermoplastic resin composition according to claim 3, wherein the thermoplastic resin is a vinyl chloride resin. 5. The thermoplastic resin composition according to claim 3, wherein the thermoplastic resin is a polycarbonate resin. 6. The thermoplastic resin composition according to claim 3, wherein the thermoplastic resin is a polyester resin. The thermoplastic resin composition according to claim 3. 7. The thermoplastic resin composition according to claim 3, characterized in that the thermoplastic resin is an acrylonitrile-styrene resin. 8. The thermoplastic resin composition is methacrylic. 4. The thermoplastic resin composition according to claim 3, which is a methyl acid-styrene resin.