JPH10139833A - Production of weather-proof, thermoplastic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing the subject resin excellent in impact resistance and the appearance of the molded products therefrom by graft polymerization of a vinyl monomer mixture with a specific base rubber produced from an acrylic ester-based monomer and allyl-free multifunctional vinyl monomer. SOLUTION: This method reacts (B) 40 to 200 pts.wt. of a vinyl monomer mixture by emulsion graft polymerization with (A3 ) 100 pts.wt. of cross-linked acrylic rubber copolymer particles which constitute (A) the base rubber containing at least 70wt.% of gel, produced by emulsion polymerization of (A1 ) a vinyl monomer-based mixture with an acrylic ester as the major ingredient and (A2 ) an allyl-free multifunctional vinyl monomer-based mixture, where a mixture comprising A1 and 0.01 to 7mol% of A2 based on A1 is supplied to the reaction system at a rate of 1×10<20> to 1×10<-17> mol/min per mol of A3 , and rate of radical formation in the presence of a water-soluble initiator is adjusted to 3×10<-25> to 3×10<-22> mol/min per mol of A3 .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a weather-resistant thermoplastic resin. More specifically, it is a thermoplastic resin obtained by graft-polymerizing a vinyl monomer mixture containing an aromatic vinyl monomer to a specific acrylic rubbery copolymer, and has excellent impact resistance and surface appearance. The present invention relates to a method for producing a weather-resistant thermoplastic resin from which is obtained.

[0002]

2. Description of the Related Art Many impact-resistant resins produced by polymerizing a monomer that gives a hard resin component in the presence of a rubbery polymer have been known. Among these, ABS resin composed of polybutadiene / styrene / acrylonitrile is a typical one, and is excellent in various physical properties such as a balance between impact resistance and molding workability. It is widely used in various fields including home appliances. However, the ABS resin has a disadvantage that it has a large amount of unsaturated bonds in a rubber component serving as a base, so that there is a limit to outdoor use and long-term indoor use. These disadvantages are:
Although it can be slightly improved by adding an ultraviolet absorber or an antioxidant to this type of resin, the weather resistance of this type of resin has not been fundamentally improved.

From such a viewpoint, various techniques using a saturated rubber having no unsaturated bond as a rubber component serving as a base have been proposed. One example of this is an AAS resin in which a diene rubber, which is a base rubber of an ABS resin, is replaced by an acrylate rubber polymer (acrylic rubber). However, acrylic rubber has disadvantages in that it has a lower modulus of elasticity, slower elastic recovery, and is more easily plastically deformed than diene rubber. Therefore, when a molded article is manufactured by injection molding using a resin such as an AAS resin based on an acrylic rubber as a molding material, the acrylic rubber particles are remarkably deformed and oriented, and the molded article has a pearly luster or gloss on its surface. Since flow marks and the like appear, the product value is reduced. Furthermore, due to the significant deformation of the rubber particles during molding, mechanical strength such as impact strength, tensile strength, and elongation may vary greatly depending on the orientation direction and the position of the molded product, resulting in variations in mechanical strength and appearance. Has also occurred.

[0004]

When the acrylic rubber is used as the base rubber, the weather resistance is greatly improved as compared with the thermoplastic resin using the unsaturated rubber as the base. There was a problem in the appearance and impact strength of the product, and no satisfactory product was obtained. In order to improve these drawbacks, for example, a method has been proposed in which an acrylic rubber is crosslinked and the degree of crosslinking is adjusted to be used as a base rubber. Increasing the degree of cross-linking improves the appearance of the above-mentioned molded article, but the impact strength is greatly reduced in accordance with the improvement of this appearance, and conversely, if the degree of cross-linking of the rubber is moderated, the impact strength is improved, but The disadvantage of poor appearance of the product has not been improved.

As a method for improving the above-mentioned disadvantages, Japanese Patent Publication No. 48-23343 and Japanese Patent Publication No. 48-18593 have been disclosed.
In Japanese Patent Application Publication No. 50-19311, it is proposed in Japanese Patent Application Laid-Open No. 50-191931 that a weathering resin having excellent impact strength can be obtained by using a crosslinking agent having an allyl group as a crosslinking agent. It is described that high impact strength can be obtained when the crosslinking agent is used.

The use of an allyl-based cross-linking agent as described in the above-mentioned publication improves the impact resistance, but it is hardly sufficient, but it is far less than that of ABS resin. Further, in the invention described in Japanese Patent Publication No. 47-47863, the impact strength is improved by using a shell-core type composite rubber having a butadiene rubber at the core of an acrylic rubber. The weather resistance of the obtained resin is inferior to that of the acrylic rubber alone. The impact resistance has been improved by increasing the amount of the rubber component in the resin.However, when the amount of the rubber component is increased, the rigidity is reduced.As a result, the impact resistance is maintained while maintaining other physical properties and properties. At present, a weather-resistant resin satisfying both the strength and the molded appearance has not been obtained.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to provide a thermoplastic resin which has eliminated the above-mentioned disadvantages of the prior art, and as a result, have found that acrylate-based monomers and allyl A polyfunctional vinyl monomer having no group,
An acrylic rubber-like polymer produced by an emulsion polymerization method under specific conditions is used as a base rubber, and a thermoplastic resin obtained by performing a graft reaction of a monomer mixture containing an aromatic vinyl monomer on the base rubber. Found that the impact strength and the appearance of the molded article could be improved simultaneously.

In order to solve the above problems, the present invention provides:
A rubber copolymer obtained by copolymerizing a vinyl monomer mixture (A) containing an acrylate ester as a main component and a polyfunctional vinyl monomer mixture (B) having no allyl group by an emulsion polymerization method. In the presence of 100 parts by weight of the polymer (C) particles,
A method for producing a weather-resistant thermoplastic resin in which 40 to 200 parts by weight of a vinyl monomer mixture (D) is emulsion-grafted and polymerized, wherein the rubbery copolymer (C) particles comprise a monomer mainly containing an acrylate ester. The mixture (A) is defined as a monomer mixture {(A) + (B)} containing 0.01 to 7 mol% of a polyfunctional vinyl monomer mixture (B) having no allyl group,
1 × 10 ^-20 to 1 × 1 per rubbery copolymer (C) particle
While being added to the reaction system at a rate of 0 ^-17 mol / min, the rate of radical generation by the water-soluble initiator is 3 × 10 ^{-25 to} 3 × 10 ^-22 mol / min per rubbery copolymer (C) particle. Polymerized under the following conditions, and a rubbery copolymer (C)
Provided is a method for producing a weather-resistant thermoplastic resin, characterized by being a crosslinked acrylic rubbery copolymer having a gel content of particles of 70% or more.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The rubber component of the substrate used in the production of the thermoplastic resin according to the present invention reacts a vinyl monomer mixture containing an acrylate ester with a polyfunctional vinyl monomer mixture having no allyl group at a specific rate. It is essential that the reaction system is charged into the reaction system at a specific rate using a water-soluble initiator, and is produced by an emulsion polymerization method.

(1) Rubbery copolymer (C) Rubbery copolymer used for producing the thermoplastic resin of the present invention
Body (C) is a monomer mainly composed of an acrylate ester
Mixture (A) having 0.01 to 7 mol% of allyl groups
Containing a multifunctional vinyl monomer mixture (B)
Rubbery copolymer as mixture {(A) + (B)}
(C) 1 × 10 per particle^-20~ 1 × 10^-17 Mol / min
While adding to the reaction system at a rapid rate,
Is 3 × 10 per particle of the rubbery copolymer (C).
^{-twenty five}~ 3 × 10^{-twenty two}It is necessary to polymerize under the condition of mol / min.
And the rubbery copolymer (C) particles obtained at this time
It is essential that the gel content of the child is 70% or more.

[0011] The amount equivalent to 0 to 30% by weight of the rubbery copolymer (C) particles may be derived from seed particles used in seed polymerization. The polymer particles that can be used as a seed are particles of a vinyl monomer mixture (A) containing an acrylate ester as a main component and / or a copolymer obtained by polymerizing another vinyl monomer. These seed particle components are effective for controlling the number of particles of the rubbery copolymer (C) in the subsequent step, but are not always essential.

[0012] The seed particle component in producing the rubbery copolymer (C) particles is preferably less than 30% by weight of the rubbery copolymer (C) particles. If the seed particle component is used in an amount of 30% by weight or more, the effect of reinforcing the rubber on the graft-polymerized resin is small, and the impact resistance is reduced. Here, the other vinyl monomer is not particularly limited, and any vinyl monomer can be used, and may contain a polyfunctional vinyl monomer regardless of the presence or absence of an allyl group.

The acrylate in the vinyl monomer mixture (A) is preferably an ester compound of a monohydric alcohol having 1 to 8 carbon atoms and acrylic acid. Specific examples of the acrylic acid alkyl ester monomer having 1 to 8 carbon atoms in the alkyl group include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, i-butyl acrylate, amyl acrylate, hexyl acrylate, and octyl acrylate. And alkyl acrylates such as 2-ethylhexyl acrylate and cyclohexyl acrylate. These ester compounds may be used alone or as a mixture of two or more.

Other vinyl monomers copolymerizable with the above-mentioned alkyl acrylate include aromatic vinyl monomers such as styrene, α-methylstyrene and vinyl toluene, and vinyl cyanides such as acrylonitrile and methacrylonitrile. Monomer, acrylate monomer other than the above, methacrylate, acrylamide, methacryloamide, vinylidene chloride, alkyl (1 to 1 carbon atoms)
6) Vinyl ethers and the like, which may be one kind or a mixture of two or more kinds.

The vinyl monomer mixture (A) comprises 60 to 100% by weight of an acrylate ester and 0 to 40% by weight of another vinyl monomer copolymerizable therewith. The amount is preferably at least 60% by weight.
If the content is less than 60% by weight, the effect of reinforcing the rubber on the graft-polymerized resin is small, and the impact resistance is reduced.

The polyfunctional vinyl monomer mixture (B) copolymerized with the vinyl monomer mixture (A) containing an acrylate ester is not particularly limited as long as it has no allyl group. Specific examples of the polyfunctional vinyl monomer having no allyl group include aromatic polyfunctional vinyl monomers such as divinylbenzene and divinyltoluene, ethylene glycol dimethacrylate, nanoethylene glycol dimethacrylate, and propylene glycol dimethacrylate. And methacrylates of polyhydric alcohols such as nano-propylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, and trimethylolpropane triacrylate. These may be one kind or a mixture of two or more kinds.

The polyfunctional vinyl monomer mixture (B) having no allyl group is a vinyl monomer mixture containing an acrylate ester as a main component so that (B) is 0.01 to 7 mol%. Mix with (A). When (B) is less than 0.01 mol%, the degree of crosslinking of the rubbery copolymer is small, and the impact strength and
The appearance of the molded article is not improved, and if it exceeds 7 mol%, the appearance of the molded article is improved, but the impact strength is reduced.
Neither is preferred.

A mixture of a vinyl monomer mixture (A) containing an acrylate ester as a main component and a polyfunctional vinyl monomer mixture (B) having no allyl group {(A) + (B)}
Is 1 × 10 ^-20 to 1 per particle of the rubbery copolymer (C).
It is added to the reaction system at × 10 ^-17 mol / min. Feed rate per rubbery copolymer (C) particle is 1 × 10 ^-20 mol /
If it is less than 1 minute, the gel content of the obtained rubbery copolymer (C) will be low, and if it exceeds 1 × 10 ^-17 mol / min, a large amount of monomer droplets will remain and the emulsion system will be unstable. Are not preferred. Among them, particularly preferred is a range of 1 × 10 ^{−19 to} 7 × 10 ⁻¹⁸ mol / min.

In the present invention, the number of particles of the rubbery copolymer (C) can be calculated, for example, from the particle diameter measured by the photon correlation method and the weight of the rubbery copolymer (C). The number of particles is controlled mainly by the type and amount of the emulsifier, and is obtained by polymerizing a vinyl monomer mixture (A) containing an acrylate ester as a main component and / or another vinyl monomer. It can also be controlled by using the resulting copolymer latex particles as seeds in the range of 0 to 30% by weight of the rubbery copolymer (C) particles.

The rate of addition of the monomer mixture {(A) + (B)} per particle of the rubbery copolymer (C) to the reaction system is 1
The method of adjusting the concentration in the range of × 10 ^-20 to 1 × 10 ^-17 mol / min includes (1) a method of adding continuously, (2) a method of adding intermittently at regular intervals, and (3) When the amount is small, a method of adding all at once may be used.

The polymerization reaction for obtaining the rubbery copolymer (C) is carried out by an emulsion polymerization method using a water-soluble initiator. The polymerization initiator is not particularly limited as long as it is a water-soluble initiator, and both inorganic peroxides such as potassium persulfate, sodium persulfate, and ammonium persulfate, and both organic peroxides are water-soluble. is not. Depending on the polymerization temperature, the kind and amount of the water-soluble initiator are such that the radical generation rate in the reaction system is 3 × 10 3 per rubbery copolymer (C) particle.
^{-25 to} 3 × 10 ^-22 mol / min.

When the radical generation rate in the reaction system is higher than 3 × 10 ⁻²² mol / min per particle, the amount of gel formed in the rubbery copolymer decreases, and both the impact strength and the appearance of the molded article are reduced. Both get worse. When the radical generation rate in the reaction system is less than 3 × 10 ⁻²⁵ mol / min per particle, not only the gel content of the rubbery copolymer (C) decreases, but also the polymerization rate decreases, This is not preferable because productivity is deteriorated and a large amount of monomer droplets remain, causing problems such as destabilization of the emulsification system. Among them, particularly preferred is a range of 1 × 10 ⁻²⁴ to 1 × 10 ⁻²² mol / min per particle.

The method of controlling the rate of radical generation in the reaction system within the range of 3 × 10 ^{−25 to} 3 × 10 ⁻²² mol / min per particle is based on the decomposition rate of the initiator at the polymerization rate. 3 × 10 ^-25 per particle
A method of calculating an amount of 3 × 10 ⁻²² mol / min is employed. At this time, since the amount of radicals generated decreases with the progress of the polymerization reaction, it is necessary to appropriately add an initiator so that the amount of radicals falls within the above range.

The rubbery copolymer (C) produced under the above polymerization conditions has a gel content of 70% (the measuring method will be described later).
It is necessary to be above. If it is less than 70%, a molded article having excellent appearance cannot be obtained from the finally obtained resin, and sufficient impact strength cannot be obtained, which is not preferable.
A preferred range of the gel content is 80% or more.

(2) Vinyl monomer mixture (D) The rubbery copolymer (C) is used as a base rubber, and the vinyl monomer mixture (D) to be grafted (co) polymerized on the base rubber is an aromatic vinyl monomer. , Vinyl cyanide monomer and other vinyl monomers copolymerizable therewith.

As the aromatic vinyl monomer, styrene,
And side-chain or (and) nuclear-substituted styrene (substituents are lower alkyl group, lower alkoxy group, trifluoromethyl group, halogen atom, etc.), for example, α-methylstyrene, p-methylstyrene, o-methyl Styrene, m-methylstyrene, nuclear halogenated styrene and the like can be mentioned. These may be used together within a group or between groups. Examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, and α-chloroacrylonitrile. These may be one kind or a mixture of two or more kinds.

Vinyl monomers copolymerizable with the above monomers include acrylic acid, methacrylic acid, and (meth)
Acrylic acid ester monomer, acrylamide, methacryloamide, vinylidene chloride, alkyl (1 to 1 carbon atoms)
6) Vinyl ethers and the like, and these may be used alone or as a mixture of two or more.

In the presence of the acrylic rubbery copolymer (C), the weight ratio of the vinyl monomer to be graft-polymerized thereto is 100 to 20% by weight of an aromatic vinyl monomer, respectively.
It is selected in the range of 0 to 50% by weight of a vinyl cyanide monomer and 0 to 80% by weight of another vinyl monomer copolymerizable therewith. If the amount of the vinyl cyanide monomer is larger than these weight ratio ranges, the workability and color tone of the finally obtained resin are undesirably reduced.

In the presence of the acrylic rubbery copolymer (C), a vinyl monomer mixture to be graft-polymerized thereto is
It should be selected in the range of 40 to 200 parts by weight with respect to 100 parts by weight (solid content basis) of the acrylic rubbery copolymer. If the amount of the monomer mixture is less than 40 parts by weight, the graft ratio of the resin finally obtained becomes small, the impact resistance is lowered, and a molded article having an excellent appearance cannot be obtained. When the amount exceeds 200 parts by weight, the graft ratio becomes saturated and constant, and only the hard resin that has not been graft-polymerized increases, and the concentration of the acrylic rubbery copolymer in the finally obtained resin decreases. Not preferred.

For the graft polymerization reaction, an emulsion polymerization method or an emulsion-suspension polymerization method is generally employed in view of easiness in control of the reaction and operability. A radical polymerization initiator is used in the graft polymerization reaction, and conventionally known organic peroxides and inorganic peroxides are used without any particular limitation. Among them, redox initiators (eg, cumene hydroperoxide / glucose / Fe ²⁺ ) are preferred from the viewpoint of the color tone of the finally obtained resin. When performing the graft polymerization reaction, a chain transfer agent can be used as necessary.

(3) Thermoplastic resin (F) The weatherable thermoplastic resin (E) obtained by the method according to the present invention can be used as it is as a molding material. Further, as a resin composition (G) mixed with another thermoplastic resin (F), a molding material of weather resistant and impact resistant resin can be used. Other thermoplastic resins (F) include, for example, polystyrene, high impact polystyrene, acrylonitrile / styrene copolymer (AS resin), styrene / maleic anhydride copolymer (SMA resin), acrylonitrile / butadiene / styrene copolymer Combined (ABS resin), acrylonitrile / butadiene / styrene / α-
Methylstyrene copolymer (heat-resistant ABS), acrylonitrile-ethylene-propylene-diene-styrene copolymer (AES resin), methyl methacrylate-butadiene-styrene copolymer (MBS resin), methyl methacrylate-acrylonitrile-butadiene-styrene Copolymers (MABS), polymethyl methacrylate, polyvinyl chloride, polycarbonate, polyamide, polybutylene terephthalate, polyphenylene oxide and the like can be mentioned. In order to obtain the resin composition (G), the type and proportion of the other thermoplastic resin (F) to be combined with the thermoplastic resin (E) are selected according to the intended use, and both are conventionally known. Kneading and mixing may be performed depending on the method.

The weatherable thermoplastic resin (E) and the resin composition (G) comprising the thermoplastic resin (E) and the other thermoplastic resin (F) obtained according to the present invention include these resins. (E) and / or (G) types and amounts of lubricants, release agents, plasticizers, colorants, ultraviolet absorbers, weathering stabilizers, heat resistance stabilizers, fillers, Various resin additives such as a flame retardant, a flame retardant auxiliary, and a foaming agent can be added in an appropriate combination.

The resin composition (G) mixed with the weather-resistant thermoplastic resin (E) and another thermoplastic resin (F) obtained according to the present invention is excellent in weather resistance, impact resistance and appearance. Since such molded articles are obtained, they are used for the production of electric parts used for a long period of time outdoors and indoors, and various industrial parts. Applicable molding methods are injection molding methods, extrusion molding methods, compression molding methods, hollow molding methods, and other conventionally known molding methods.

[0034]

The present invention will be described below in more detail with reference to examples and comparative examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention. In the following examples, "parts" means parts by weight, and the physical properties of the thermoplastic resin were measured by the following methods.

(1) Method for Determining Gel Content of Rubber Copolymer Particles (C) After the latex immediately after polymerization is freeze-dried, about 100 times the amount of solid content of methyl ethyl ketone (MEK) is added and stirred for 5 hours. Then, the solid content was dispersed in MEK. Subsequently, ultrasonic treatment for 5 minutes (irradiator: UT manufactured by SHARP)
-604, at the maximum output), followed by stirring overnight for dispersion (gel content) and dissolution (soluble component).
This solution is centrifuged (Hitachi vacuum high-speed cooling centrifuge,
CR-26H) at 22,000 rpm for 1 hour, then separate the supernatant and sediment, repeat the MEK washing and centrifugation, and dry under reduced pressure. The rate (%) was calculated. All treatments were performed at room temperature except for the freeze-drying operation.

(2) Izod impact strength Measured according to JIS K7110. Unit: kg-cm /
cm (3) Drop weight impact Specimen (150mm × 150mm ×
A 2.5 mm square plate) was measured at 23 ° C. with an impact tester manufactured by ETI, USA, and the energy (J: joule) required for the falling weight to completely pass through the test piece was measured.

(4) Weather resistance test A test piece for Izod (with a notch) was measured using a sunshine weatherometer (WEL-SUN-D, manufactured by Suga Test Instruments Co., Ltd.).
C) after exposure at 60 ° C. for 600 hours.
zod) The impact strength was measured and judged by comparing with the value before exposure.

(5) Appearance Appearance of a test piece (75 mm × 160 mm × 2.5 mm rectangular flat plate) manufactured by injection molding using a pellet of a resin composition mixed with carbon black for color. Was visually observed and judged according to the following criteria. ：: Neither pearly luster nor flow mark is recognized at all, ○: Neither pearly luster nor flow mark is recognized, Δ: Pearlescent luster and / or flow mark are slightly recognized, ×: Pearlescent luster And flow marks are both significant.

(6) Gloss Test pieces (75 mm × 160) manufactured by the injection molding method
The gloss value of the surface of each rectangular flat plate (mm × 2.5 mm) was measured using a variable-angle gloss meter (VGS-30 manufactured by Nippon Denshoku Industries Co., Ltd.).
(0A type), measurement was performed at 10 points at an incident angle of 60 degrees, and the average value was calculated and displayed.

[Production Example-1] <Production Example of Seed Particles of Rubber Copolymer (C)> 1-1 In a glass flask having a capacity of 5 L, 151 parts of water and a higher fatty acid soap (mainly containing 18 carbon atoms) were placed. 2 parts of a sodium salt of a fatty acid, and 1 part of sodium hydrogen carbonate, and heated to 75 ° C. in a nitrogen stream. Potassium persulfate (KPS) 0.1
Five minutes after the addition of 35 parts, 4 parts of 100 parts of butyl acrylate (BA) were charged. An exotherm occurred in about several minutes, confirming the start of polymerization. First BA4
Twenty minutes after charging the parts, continuous addition of the remaining monomer (BA 96 parts) was started, and the addition was terminated when three hours and twenty minutes passed. During this process, 1 part of fatty acid soap was added 2 hours after the start of the addition, and 0.015 part of potassium persulfate was added 2 hours 30 minutes later.
Each was additionally added to the flask. After the monomer addition,
The temperature inside the flask was raised to 80 ° C. and maintained at this temperature for an additional hour. The obtained polybutyl acrylate (1-1)
Was 1%.

1-2 In the example described in 1-1, except that the BA of the vinyl monomer was changed to a mixture of 95 parts of styrene and 5 parts of allyl methacrylate (AMA), the same procedure as in 1-1 was used. Polymerized. The gel content of the obtained polymer (1-2) is
100%.

[Production Example-2] <Preparation of vinyl monomer mixture (A) containing acrylate ester as a main component> A-1 was prepared from 100 parts by weight of butyl acrylate (BA), and 95 parts by weight of BA A-2 is a monomer mixture composed of acrylonitrile and 5 parts by weight of acrylonitrile.

<Production Example of Rubber Copolymer Particles (C)> C-1 In a 5 L glass flask, 151 parts of deionized water,
1 part of sodium hydrogen carbonate and 2 parts (solid content) of the above-mentioned 1-1 latex were charged, and the temperature inside the flask was raised to 75 ° C under a nitrogen stream. 0.006 parts of potassium persulfate (KPS) as a radical initiator was added to the flask (1 × 10 ⁻²³ mol / min per particle), and after 5 minutes had passed, the above 1-1 (BA) ｛= (A) {98 parts and ethylene glycol methacrylate (EGDM)} =
(B) in {(A) + (B)} is 0.35 mol%] with 8 × 10 ⁻¹⁹ mol / mol of the above-mentioned 1-1 particle. Minutes and continuously charged into the reactor (total addition time: about 148 minutes). After several minutes, heat was generated, and the initiation of polymerization was confirmed.

Until the continuous charging of the vinyl monomer mixture {(A) + (B)} into the reactor is completed, a higher fatty acid soap (sodium salt of a fatty acid whose main component is a fatty acid having 18 carbon atoms) Was added every 10 minutes and at the end of the charging of the vinyl monomer mixture so as not to generate new particles, and potassium persulfate was added to the reactor at any time in order to maintain the amount of radicals. For 4 hours from the start of the charging of the vinyl monomer mixture, the internal temperature of the reactor is maintained at a constant temperature, and a copolymerization reaction is performed to obtain rubbery copolymer (C-1) particles. Was. The gel content of C-1 was 85%.

C-2 The rubbery copolymer was prepared in the same manner as in the production example of C-11 except that EGDM was replaced with divinylbenzene (DVB) in the production example of the rubbery copolymer C-1. Particles (C-2) particles were obtained. Its gel content is 87%
It was.

C-3 In the production example of the rubbery copolymer C-1, the charging rate of the vinyl monomer mixture {(A) + (B)} into the reactor was
Rubbery copolymer (C-3) particles were obtained by the same procedure as in the production example of C-11, except that the speed was changed to 9 × 10 ⁻¹⁸ mol / min per particle. The gel content of C-3 was 92%.

C-4 In the production example of the rubbery copolymer C-1, the charging rate of the vinyl monomer mixture {(A) + (B)} into the reactor was
Rubbery copolymer (C-4) particles were obtained by the same procedure as in the production example of C-11, except that the speed was changed at a rate of 2 × 10 ^-20 mol / min per particle. The gel content of C-4 was 72%.

C-5 In the production example of the rubbery copolymer C-1, the charging rate of potassium persulfate (KPS) into the reactor was set at 1 per particle.
X 10 ^-22 mol / min, except that the rubbery copolymer (C
-5) Particles were obtained. The gel content of C-5 was 73%.

C-6 In the production example of the rubbery copolymer C-1, the charging rate of potassium persulfate (KPS) into the reactor was set to 3 per particle.
^{Except that} the rate was changed to × 10 ^-25 mol / min, the rubbery copolymer (C-
6) Particles were obtained. The gel content of C-6 was 91%.

C-7 The procedure of preparing the rubbery copolymer C-1 was repeated except that the monomer mixture (A) was changed to the above-mentioned A-2. The copolymer (C-7) particles were obtained. The gel content of C-7 was 87%.

C-8 In the production example of the rubbery copolymer C-1, except that the type of latex initially charged into the reactor was changed to the latex 1-2 described above, By the same procedure, rubbery copolymer (C-8) particles were obtained. C-
The gel content of No. 8 was 94%.

C-9 In the production example of the rubbery copolymer C-1, 28 parts of the latex of 1-1 was used, and the vinyl monomer mixture {(A) +
(B) C was used except that the amount of use in (2) was changed to 72 parts.
In the same manner as in Production Example 1, rubbery copolymer (C-9) particles were obtained. Gel content of C-9 is 72%
It was.

C-10 In the production example of the rubbery copolymer C-1, the vinyl monomer mixture {(A) +
(B) The rubbery copolymer (C) was prepared in the same manner as in the production example of C-1 except that the amount of｝ was changed to 100 parts.
-10) Particles were obtained. The gel content of C-10 was 93%.

C-11 In the production example of the rubbery copolymer C-1, in the vinyl monomer mixture {(A) + (B)}, the polyfunctional vinyl monomer mixture having no allyl group (B ) Was changed to 6.5 mol%, and rubbery copolymer (C-11) particles were obtained by the same procedure as in the production example of C-1. C-11
Was 94%.

C-12 In the production example of the rubbery copolymer C-1, the polyfunctional vinyl monomer mixture (B) having no allyl group in the vinyl monomer mixture {(A) + (B)} was used. ) Was changed to 0.03 mol%, and rubbery copolymer (C-12) particles were obtained by the same procedure as in the production example of C-1. C-1
The gel content of No. 2 was 73%.

C-13 In the production example of the rubbery copolymer C-1, 28 parts of the latex 1-1 was used, and the vinyl monomer mixture {(A) +
(B) Production example of C-1 except that the amount of｝ was changed to 72 parts and the charging rate of potassium persulfate (KPS) was changed to 1 × 10 ⁻²² mol / min per particle. The rubbery copolymer (C-1)
3) Particles were obtained. The gel content of C-13 was 65%.

C-14 The same procedure as in the production example of C-1 except that the radical initiator was changed to di-t-butyl peroxide (DTBPO) in the production example of the rubbery copolymer C-1. As a result, rubbery copolymer (C-14) particles were obtained. C-14
Was 95%.

C-15 In the production example of the rubbery copolymer C-1, 50 parts of the latex 1-1 was mixed with a vinyl monomer mixture {(A) +
(B) The rubbery copolymer (C) was produced in the same manner as in the production example of C-1 except that the amount of｝ was changed to 50 parts.
-15) Particles were obtained. The gel content of C-15 was 52%.

C-16 In the production example of the rubbery copolymer C-1, in the vinyl monomer mixture {(A) + (B)}, the polyfunctional vinyl monomer mixture having no allyl group (B) ) Was changed to 10 mol%, and rubbery copolymer (C-16) particles were obtained by the same procedure as in the production example of C-1. C-16
Was 98%.

C-17 In the production example of the rubbery copolymer C-1, the addition rate of the vinyl monomer mixture {(A) + (B)} to the reactor was set to 5 × 10 ^-21 mol per particle. Other than changing the speed to / min,
Rubbery copolymer (C-17) particles were obtained by the same procedure as in the production example of C-1. The gel content of C-17 was 3%.

C-18 In the production example of the rubbery copolymer C-1, the addition rate of potassium persulfate (KPS) to the reactor was 1 × per particle.
Production Example C-1 ^{except that} the speed was changed to 10 ⁻²¹ mol / min.
Rubbery copolymer (C-18) particles were obtained by the same procedure as in Production Example 1. The gel content of C-18 is 48
%Met.

C-19 In the production example of the rubbery copolymer C-1, except that the EGDM which is the polyfunctional vinyl monomer mixture (B) was changed to allyl methacrylate (AMA), According to the same procedure as in the production example, the rubbery copolymer (C-19)
Particles were obtained. The gel content of C-19 was 95%.
Table 1 summarizes the contents described above.

[0063]

[Table 1]

[Note] The abbreviations in Table 1 have the following meanings. EGDM: ethylene glycol dimethacrylate, DB
V: divinylbenzene, AMA: allyl methacrylate {not applicable to (B) because it has an allyl group, but described for convenience in (B)}, KPS: potassium persulfate, DTBPO: di-t-butyl par oxide

[0065]

【Example】

<Production of thermoplastic resin (E)> [Example 1] A stirring device, a heating / cooling device, each raw material,
100 parts of the above rubbery copolymer particles C-1 as a solid content, 1.0 part of sodium pyrophosphate, 0.25 part of glucose, and 0 part of ferrous sulfate in a 5 L capacity reactor equipped with an auxiliary charging device. .01 parts and 258 parts of deionized water (including the water content of latex) were charged, and the internal temperature of the reactor was raised. Internal temperature is 7
When the temperature reached 0 ° C., 70 parts of styrene, 30 parts of acrylonitrile, 0.20 part of t-dodecyl mercaptan, 0.5 part of cumene hydroperoxide, 1.8 parts of disproportionated potassium rosinate soap, 1.8 parts of deionized water 48 parts were continuously added to the reactor over a period of 3 hours and 30 minutes. After the addition was completed, the reaction was continued at the same temperature for another 30 minutes, and the reaction was terminated by cooling the reactor.

To this graft copolymer latex, a total of 2.5 parts of a phenolic and phosphorus-based antioxidant was added, and then added to an aqueous magnesium sulfate solution heated to 95 ° C. with stirring to coagulate. The solidified product was washed with water and dried to obtain a white powdery weatherable thermoplastic resin composition E-1.

[Examples 2 to 12] In the example described in Example 1, rubber-like copolymer particles C-1 were changed to C-2 to C-12 shown in Table-2. Prepares a graft copolymer latex in the same procedure as in the same example, adds an antioxidant, and prepares the weatherable thermoplastic resin composition E.
-2-E-12 were obtained.

Comparative Examples 1 to 7 In the example described in Example 1, rubbery copolymer particles C-1 were changed to C-13 to C-19 described in Table 2. Prepares a graft copolymer latex in the same procedure as in the same example, adds an antioxidant, and prepares the weatherable thermoplastic resin composition E.
-13 to E-19 were obtained.

Comparative Example 8 In the example described in Example 1, the rubbery copolymer particles C-1 were changed to C-2, and the vinyl monomer mixture was changed to 21 parts of styrene and acrylonitrile 9
Parts, except that the mixture was changed to a mixture consisting of 2 parts by weight, a graft copolymer latex was produced in the same procedure as in the same example, an antioxidant was added, and the weatherable thermoplastic resin composition (E-2
0) was obtained.

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[Table 2]

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[Reference example]

Evaluation test for resin composition (G) obtained by mixing weatherable thermoplastic resin (E) and other thermoplastic resin (F)

Reference Examples 1 to 12 The above-mentioned weatherable thermoplastic resin compositions (E-1 to E-12) and A for dilution
S resin (F) (Mitsubishi Chemical Corporation, trade name: SAN-L)
Were mixed in the proportions shown in Table 3, respectively, and 0.3 parts by weight of an ultraviolet absorber (trade name: Tinuvin-P, manufactured by Ciba Geigy) and 100 parts by weight of the total amount of the resin, 0.2 parts by weight of Sankyo (trade name: Sanol 770), 0.1 parts by weight of an antioxidant (trade name: Irganox 1076, manufactured by Ciba-Geigy), and 0.1 parts by weight of magnesium stearate Parts were added and kneaded with a Banbury mixer to obtain pellets of the resin composition (G). Using these pellets, test specimens for measuring physical properties and weather resistance were molded by an injection molding machine, and various physical properties were measured by the above evaluation methods. Table 3 also shows the measurement results.

[Comparative Reference Examples 1 to 8] The above-mentioned weatherable thermoplastic resin compositions (E-13 to E-20) and the AS resin for dilution (F) (same as above) are shown in Table 4 respectively. Mix in the proportions described, in the same procedure as in the above reference example, ultraviolet absorber, light stabilizer, antioxidant, and
After adding the same amount of magnesium stearate,
The mixture was kneaded with a Banbury mixer and pelletized. Using the pellets, test pieces were molded by an injection molding machine, and various physical properties were measured. Table 4 also shows the measurement results.

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[Table 3]

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[Table 4]

The following becomes clear from Tables 3 and 4. (1) The weatherable thermoplastic resin (E) according to the present invention not only has excellent Izod impact strength and falling weight impact strength, but also has a pearl-like luster, no flow mark, and a good luster on the molded product surface. Demonstrates excellent properties (Reference Examples 1 to
Reference Example 12). (2) In addition, when the weatherable thermoplastic resin (E) according to the present invention and another thermoplastic resin (F) are mixed to form a thermoplastic resin composition (G), a molded article having excellent compatibility is obtained. A molded product having excellent impact strength and excellent molded appearance can be obtained without causing delamination on the surface (Reference Examples 1 to 12). (3) The weather-resistant thermoplastic resin (E) according to the present invention does not impair the original weather resistance of the weather-resistant resin obtained by a conventional method (Reference Examples 1 to 12). (4) The weatherable thermoplastic resin (E) according to the present invention is superior in molding appearance and impact strength as compared with the case where an allyl-based polyfunctional vinyl monomer is used (Reference Example 7).

(5) On the other hand, when the gel content is small (Comparative Reference Example 1) or when an oil-soluble initiator is used (Comparative Reference Example 2), the vinyl monomer mixture ｛(A) + ( B) When｝ is less than 70% (Comparative Reference Example 3), ｛(A) +
(B) When the mole fraction of (B) in (1) is out of the range (Comparative Reference Example 4), when the supply rate of ((A) + (B)) to the reaction system is low (Comparative Reference Example) 5) If the rate of radical generation is too high (Comparative Reference Example 6), those which do not satisfy the conditions defined in claim 1 will not have excellent impact strength and will not have excellent appearance of the molded product. (6) Even when the gel content is sufficient, when the amount of the monomer at the time of graft polymerization is small (Comparative Reference Example 8), the obtained resin composition has poor impact strength and Excellent molded products cannot be obtained.

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As described above, the present invention has the following particularly advantageous effects, and its industrial utility value is extremely large. 1. ADVANTAGE OF THE INVENTION According to the manufacturing method which concerns on this invention, although the weather resistance and chemical resistance are excellent, the impact resistance is inferior and the weather resistance which the acrylic rubber containing styrene resin (commonly known as AAS resin) whose use was restricted was limited. It is possible to produce a weather-resistant thermoplastic resin which is excellent in impact resistance and which can provide a molded article having excellent surface appearance without loss. 2. Since the weatherable thermoplastic resin obtained by the method of the present invention has excellent compatibility with other hard thermoplastic resins, by kneading and mixing, it is excellent in impact resistance, weather resistance, etc., and excellent in surface appearance. In addition, it is possible to produce a resin composition that can obtain a molded product that does not cause delamination.

Claims (3)

[Claims] 1. An emulsion polymerization method comprising copolymerizing a vinyl monomer mixture (A) containing an acrylate ester as a main component and a polyfunctional vinyl monomer mixture (B) having no allyl group. In the presence of 100 parts by weight of the obtained rubbery copolymer (C) particles, a vinyl monomer mixture (D) 40 to 200
In a method for producing a weather-resistant thermoplastic resin in which a part by weight is subjected to emulsion graft polymerization, a rubbery copolymer (C) particle comprises a monomer mixture (A) containing an acrylate ester as a main component,
Monomer mixture containing 0.01 to 7 mol% of polyfunctional vinyl monomer mixture (B) having no allyl group {(A) +
(B) As 1｝, 1 × per rubbery copolymer (C) particle
While being added to the reaction system at a rate of 10 ^-20 to 1 × 10 ^-17 mol / min, the rate of radical generation by the water-soluble initiator is 3 × 10 ^{-25 to} 3 × 10 3 per rubbery copolymer (C) particle. It is a crosslinked acrylic rubbery copolymer which is polymerized under the condition of ^-22 mol / min and has a gel content of rubbery copolymer (C) particles of 70% or more. And
A method for producing a weather-resistant thermoplastic resin. 2. A vinyl monomer mixture (A) contained in a rubbery copolymer (C) comprising 60 to 100% by weight of an acrylate monomer component having 1 to 8 carbon atoms in an alkyl group;
0 to 40% by weight of another vinyl monomer copolymerizable therewith
The method for producing a weather-resistant thermoplastic resin according to claim 1, comprising: 3. The vinyl monomer mixture (D) comprises 100 to 20% by weight of an aromatic vinyl monomer, 0 to 50% by weight of a vinyl cyanide monomer, and another vinyl copolymerizable therewith. A monomer mixture containing 0 to 80% by weight of a monomer,
A method for producing a weatherable thermoplastic resin according to claim 1.