JPH08337702A - Antistatic acrylic resin composition and its production - Google Patents

Abstract

PURPOSE: To object the subject composition comprising an acrylic resin, a specific polyetherester containing a sulfonate salt group-containing aromatic dicarboxylic acid, and a surfactant, not causing the deterioration of the antistaticity, even when washed with water, and having good transparency and antistaticity. CONSTITUTION: This antistatic acrylic resin composition comprises (A) 100 pts.wt. of an acrylic resin, (B) a polyether ester produced by polycondensing (i) a 6-20C dicarloxylic acid and/or its ester containing 3-50mol% of an aromatic dicarboxylic acid and/or its ester substituted with a salt of a sulfonic acid expressed by the formula (Ar is a tervalent 6-12C aromatic group; R<1> and R<2> are each H, a 1-6C alkyl, a 6-12C aryl; M is a metallic ion, a tetra- alkylphosphonium ion, a tetraalkylammonism ion) with (ii) a poly(alkylene oxide) glycol having a number-average mol.wt. of 200-50000 and (iii) a 2-10C glycol, and (C) a surfactant. Therein, the content of component (ii) is 10-90wt.% of the component B.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an acrylic resin composition having an antistatic effect. More specifically, an acrylic resin composition comprising an acrylic resin and a polyether ester having a refractive index difference between the acrylic resin and a specific range, and having excellent transparency and having an antistatic effect lasting, The manufacturing method is related.

[0002]

2. Description of the Related Art Plastic materials are used as electric and electronic parts, automobile parts, medical parts, daily necessities, and other various molded products, making use of their excellent characteristics. By the way, in general, plastic is characterized by high electrical insulation, but because of that, static electricity on the contrary is less likely to dissipate, dust adheres to products, electric shock to workers,
Problems such as malfunction of instruments and IC chips have occurred. Therefore, studies on antistatic methods have been conducted for various plastic materials.

As an antistatic method for plastics, there are an internal addition type and a coating type. The coating type requires a separate process, and the internal addition type is more advantageous in the manufacturing process.

In the internal addition type method, a method in which an ionic surfactant such as an alkyl sulfonate or an alkylbenzene sulfonate is kneaded into a polymer has been generally adopted because of its excellent effect and economy. It was Among them, many utilizing alkyl (aryl) sulfonate have been carried out. Among them, as the resin having the antistatic effect while maintaining the original transparency, for example, in JP-A No. 7-18137, methyl methacrylate-styrene copolymer resin and phosphonium sulfonate salt are used. Compositions are disclosed. This is because the surfactant oozes to the surface,
Although the addition of a small amount of phosphonium sulfonate shows an excellent antistatic effect, there is a problem in that the antistatic effect decreases when wiped or washed with water.

On the other hand, as a method of imparting a permanent antistatic effect, a method of mixing an antistatic polymer has been disclosed. For example, JP-A-58-118838 describes that a composition comprising polyolefin and polyetheresteramide has an antistatic effect. However, when such polymers are mixed with each other, the molded product becomes cloudy and opaque because the polymer itself is crystalline or is a block polymer.
Further, even if the molded product is transparent, there is a problem that the antistatic effect is small in the case where the polymers are melted together.

By the way, Japanese Patent Application Laid-Open No. 6-57153 reports a polyether ester composed of polyalkylene glycol, glycol and polyvalent carboxylic acid. Although it has a permanent antistatic property, the effect is insufficient by itself, and it is necessary to use an ionic antistatic agent together in order to further enhance the effect. However, in such a case, there is a problem that the antistatic effect is considerably reduced by washing with water.

As described above, it has been difficult to obtain an acrylic resin composition having a permanent antistatic effect, transparency, good physical properties, and heat resistance.

[0008]

The object of the present invention is to produce a permanent antistatic effect by melt-mixing with various acrylic resins and to reduce the transparency, physical properties, moldability and heat resistance. It is to provide a small amount of an acrylic resin composition. Further, this antistatic resin composition has low industrial cost and can be produced using conventional polyester production facilities, and therefore has great industrial significance.

[0009]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a specific polyether containing a specific aromatic dicarboxylic acid component nucleus-substituted with a sulfonate group. By mixing an ester and a surfactant with an acrylic resin, a permanent antistatic effect is exhibited, and further, an acrylic resin composition with less deterioration in transparency, physical properties, moldability and heat resistance is obtained. As a result, they have arrived at the present invention.

That is, the present invention is based on the acrylic resin (A).
100 parts by weight, (B1) C6 to C20 dicarboxylic acid and / or ester thereof, (B2) number average molecular weight 20
Polyester ester (B) 5 to 30 obtained by polycondensation of 0 to 50000 poly (alkylene oxide) glycol and (B3) glycol having 2 to 10 carbon atoms.
And a resin composition comprising 0.5 to 6 parts by weight of a surfactant (C), the above (B1) is represented by the following formula (1):

[0011]

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[In the formula (1), Ar is 3 having 6 to 12 carbon atoms.
Valent aromatic group, R ¹ and R ² are each independently a hydrogen atom,
It represents an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms, and M ⁺ represents a metal ion, a tetraalkylphosphonium ion or a tetraalkylammonium ion. ] The aromatic dicarboxylic acid and / or its ester (B1 ′) substituted with a sulfonate group represented by
To 50 mol% and the content of the above (B2) constituting the above polyether ester (B) is (B1),
It is in the range of 10 to 90% by weight of the total amount of (B2) and (B3), and is composed of the refractive index of the acrylic resin (A), the polyether ester (B) and the surfactant (C). The difference from the refractive index of the mixture is 0.03 or less, which is an antistatic acrylic resin composition.

The present invention will be described in detail below.

The resin composition of the present invention consists essentially of an acrylic resin (A), a polyether ester (B) and a surfactant (C).

In the present invention, the acrylic resin (A)
, The refractive index difference of the mixture of the polyether ester (B) and the surfactant (C) is 0.
It is an essential condition that it is within 03. The refractive index difference is 0.
It is preferable that the value is within 03 in the entire visible light region, but practically, it is necessary that the difference in refractive index at least in the D line (wavelength 589 nm) of the Brownhofer line is within 0.03. When the difference in refractive index is larger than 0.03, light is scattered in the boundary region between the acrylic resin (A) component and the polyether ester (B) component in the resin composition, resulting in turbidity in the molded product. . The difference in refractive index is preferably as small as possible in terms of transparency, and more preferably within 0.02.

The above conditions can be realized in the combination of the polyether ester (B) and the surfactant (C) shown below.

Acid component constituting the polyether ester (B) in the [0017] present invention, an aromatic dicarboxylic acid and / or esters thereof having 6 to 20 carbon atoms (B1), and later of the sulfonate (-SO ₃ ^- M ⁺ ) Substituted aromatic dicarboxylic acid and / or its ester (B1 ′). Examples of the aromatic dicarboxylic acid having 6 to 20 carbon atoms include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid and 2,7-naphthalenedicarboxylic acid. 6 carbons
To 20 aromatic dicarboxylic acid esters include dimethyl terephthalate, diethyl terephthalate, dimethyl isophthalate, diethyl isophthalate, dimethyl 2,6-naphthalenedicarboxylate, diethyl 2,6-naphthalenedicarboxylate, 2,7-naphthalene Examples thereof include dimethyl dicarboxylate and diethyl 2,7-naphthalenedicarboxylate. These may have a substituent such as an alkyl group or halogen on the aromatic ring. Of these, terephthalic acid, 2,6-naphthalenedicarboxylic acid, dimethyl terephthalate, and 2,6-naphthalenedicarboxylic acid dimethyl are preferable from the viewpoint of handleability. Further, compared with the terephthalic acid component, the 2,6-naphthalenedicarboxylic acid component tends to increase the overall refractive index.

The sulfonate used in the present invention (-SO ₃ ^- M ⁺⁾ that is substituted with an aromatic dicarboxylic acid and / or its ester (B1 ') is represented by the following formula (1)

[0019]

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It is represented by

In the above formula (1), R ¹ and R ² each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 12 carbon atoms, preferably a hydrogen atom or a methyl group. And an alkyl group having 1 to 3 carbon atoms such as an ethyl group.

In the above formula (1), M ⁺ represents an ion selected from a metal ion, a tetraalkylphosphonium ion and a tetraalkylammonium ion.
M ⁺ is an alkali metal ion such as sodium ion, potassium ion or lithium ion, an alkaline earth metal ion such as calcium ion or magnesium ion,
Examples thereof include metal ions such as zinc ion, tetrabutylphosphonium ion, tetramethylphosphonium ion, tetrabutylammonium ion, tetramethylammonium ion and the like. Among these ions, metal ions are preferable, and alkali metal ions and zinc ions are more preferable.
However, in the case of a divalent metal ion, 1 mol of the metal ion corresponds to 2 mol of the sulfonate group.

Ar in the above formula (1) is a trivalent aromatic group having 6 to 12 carbon atoms such as a benzene ring and a naphthalene ring, and these are also an alkyl group, a phenyl group, a halogen, an alkoxy group and the like. It may have a substituent.

Examples of such aromatic dicarboxylic acid include 4-
Sodium sulfo-isophthalic acid, 5-sodium sulfo-isophthalic acid, 4-potassium sulfo-isophthalic acid, 5-potassium sulfo-isophthalic acid, 2-sodium sulfo-terephthalic acid, 2-potassium sulfo-terephthalic acid, 4-sulfo-isophthalic acid Zinc, 5-sulfo-
Zinc isophthalate, zinc 2-sulfo-terephthalate, 4
-Sulfo-isophthalic acid tetraalkylphosphonium salt, 5-sulfo-isophthalic acid tetraalkylphosphonium salt, 4-sulfo-isophthalic acid tetraalkylammonium salt, 5-sulfo-isophthalic acid tetraalkylammonium salt, 2-sulfo-terephthalic acid tetra Alkylphosphonium salt, 2-sulfo-terephthalic acid tetraalkylammonium salt, 4-sodium sulfo-2,
6-naphthalenedicarboxylic acid, 4-sodium sulfo-
2,7-naphthalenedicarboxylic acid, 4-potassium sulfo-2,6-naphthalenedicarboxylic acid, 4-sulfo-2,
Examples thereof include 6-naphthalenedicarboxylic acid zinc salt. Examples of the aromatic dicarboxylic acid ester include dimethyl ester and diethyl ester of the aromatic dicarboxylic acid specifically listed above.

Of these, R ¹ and R ² are both methyl groups or both ethyl groups, Ar is a benzene ring,
It is more preferable that M ⁺ is an alkali metal ion such as sodium or potassium in terms of polymerizability, mechanical properties, color tone and the like.

More preferably, 4-sodium sulfo-
Dimethyl isophthalate, 5-sodium sulfo-isophthalate dimethyl, 4-potassium sulfo-isophthalate dimethyl, 5-potassium sulfoisophthalate dimethyl, 2
-Sodium sulfo-terephthalate dimethyl, 2-potassium sulfo-terephthalate dimethyl and the like can be mentioned.

According to the present invention, from the viewpoint of the antistatic effect,
Aromatic dicarboxylic acid substituted with a sulfonate group represented by the above formula (1) and / or its ester (B1 ′)
Is 3 to 50 mol% of the total acid component (B1) used, that is, the compound represented by the formula (1) accounts for 3 to 50 mol% of the acid component constituting the polyether ester. . If the aromatic dicarboxylic acid and / or its ester (B1 ′) is less than 3 mol%, the antistatic effect is not sufficient. On the other hand, if it exceeds 50 mol%, the polymerization reaction becomes difficult, and it becomes difficult to obtain the polyether ester (B) having a sufficient degree of polymerization, or the handleability deteriorates. Aromatic dicarboxylic acid represented by the above formula (1) and /
Alternatively, the ester thereof preferably accounts for 4 to 40 mol% of the total acid component, and more preferably 5 to 30 mol%.

The glycol component constituting the polyether ester (B) in the present invention has a number average molecular weight of 20.
It is composed of 0 to 50000 poly (alkylene oxide) glycol and an aliphatic diol having 2 to 6 carbon atoms. Examples of the poly (alkylene oxide) glycol (B2) include polyethylene glycol, poly (propylene oxide) glycol, ethylene oxide adducts with bisphenols, and poly (propylene oxide) glycol copolymerized polyethylene glycol. Of these, poly (alkylene oxide) glycol mainly composed of polyethylene glycol is preferable. The poly (alkylene oxide) glycol (B2) having a number average molecular weight of 200 to 50,000 is used. If the molecular weight is less than 200, a sufficient antistatic effect cannot be obtained. In addition, from the viewpoint of practicality, the upper limit of the molecular weight is about 50,000. The number average molecular weight of the poly (alkylene oxide) glycol is preferably 500 to 40,000, more preferably 1
000 to 30,000.

From the viewpoint of the antistatic effect, the poly (alkylene oxide) glycol (B2) must account for 10 to 90% by weight of the whole polyether ester. That is, the amount of poly (alkylene oxide) glycol used is such that the content of (B2) constituting the polyether ester (B) is (B1), (B2) and (B).
It should be 10 to 90% by weight based on the total amount of 3). If it is less than 10% by weight, the antistatic effect is not sufficient, and if it is more than 90% by weight, the handling properties and heat resistance may tend to be poor. The preferred amount used is 15 based on the total amount of the resulting polyether ester (B).
To 80% by weight, more preferably 20 to 75% by weight
Is.

The copolymerization amount of the poly (alkylene oxide) glycol (B2) is such that the polyether ester (B)
Has the greatest effect on the refractive index of the mixture of the surfactant and the surfactant (C). In the present invention, the acrylic resin to be used by appropriately selecting the copolymerization amount (content) of the poly (alkylene oxide) glycol (B2) constituting the polyether ester (B) within the above-mentioned use amount range. The difference in refractive index from (A) can be made within 0.03, preferably smaller.

The glycol having 2 to 10 carbon atoms (B3) used in the present invention is specifically ethylene glycol, 1,4.
Examples include butanediol, propylene glycol, 1,6-hexanediol (1,6-hexamethylene glycol), 3-methyl-1,5-pentanediol, and the like. These may contain an ether bond or a thioether bond. Among them, 1,6-hexanediol,
3-Methyl-1,5-pentanediol is preferable from the viewpoint of antistatic effect.

The polyether ester (B) in the present invention is phenol / tetrachloroethane (weight ratio: 6).
The reduced viscosity (concentration: 1.2 g / dl) measured at 35 ° C. in a mixed solvent of 0/40) is preferably 0.3 or more. When the reduced viscosity is less than 0.3, it causes heat resistance and mechanical property deterioration. If the polymer is a substantially linear polymer, the upper limit to the reduced viscosity is preferably high in terms of antistatic effect and mechanical properties, but the upper limit of practical polymerization is about 4.0. . The reduced viscosity is more preferably 0.4 or more, and further preferably 0.5 or more.

The polyether ester (B) in the present invention comprises the above components (B1) to (B3) and (B1 ').
Can be obtained by heating and melting at 150 to 300 ° C. in the presence of an ester exchange catalyst to cause polycondensation reaction.

The transesterification catalyst is not particularly limited as long as it can be used in a general transesterification reaction. Such transesterification catalysts include antimony compounds such as antimony trioxide, tin compounds such as stannous acetate, dibutyltin oxide and dibutyltin diacetate, titanium compounds such as tetrabutyl titanate, zinc compounds such as zinc acetate and calcium acetate. Calcium compounds such as sodium carbonate,
Examples thereof include alkali metal salts such as potassium carbonate. Of these, tetrabutyl titanate is preferably used.

The catalyst may be used in a usual transesterification reaction, and is preferably 0.01 to 0.5 mol% relative to 1 mol of the acid component used, and 0.03. ˜0.3 mol% is more preferred.

It is also preferable to use various stabilizers such as antioxidants together during the reaction.

As the temperature for heating and melting and polycondensing the compounds (B1) to (B3) and (B1 '), the initial reaction is 150 to 200 ° C for several tens of minutes to several tens of hours, and the esterification reaction and After carrying out the transesterification reaction while distilling off the distillate, a polymerization reaction for polymerizing the reaction product is carried out at 180 ° C to 300 ° C. This is because if the temperature is lower than 180 ° C., the reaction does not proceed, and if the temperature is higher than 300 ° C., side reactions such as decomposition easily occur. The polymerization reaction temperature is more preferably 200 ° C to 280 ° C, further preferably 220 ° C to 250 ° C. Although the reaction time of this polymerization reaction depends on the reaction temperature and the amount of catalyst, it is usually several tens of minutes to several tens of hours.

Acrylic resin (A) used in the present invention
As polymethylmethacrylate, polyethylmethacrylate, polypropylmethacrylate, polybutylmethacrylate, polymethylacrylate, polyethylacrylate,
Methacrylic acid ester such as methyl methacrylate-methyl acrylate copolymer, methyl methacrylate-ethyl methacrylate copolymer, methyl methacrylate-butyl methacrylate copolymer, methyl methacrylate-ethyl acrylate copolymer and the like. Alternatively, a homopolymer or a copolymer of acrylic acid ester may be used. These acrylic resins may be used alone or in combination of two or more. In addition, the production method thereof is not particularly limited, and those produced by a known suspension polymerization method, emulsion polymerization method, bulk polymerization method or the like can be used.

The antistatic resin composition of the present invention contains 5 to 30 parts by weight of the polyether ester (B) and 0 part of the surfactant (C) based on 100 parts by weight of the acrylic resin (A) shown above. 0.5 to 6 parts by weight. Examples of such a surface active agent include an anionic surface active agent and a cationic surface active agent, and an anionic surface active agent is preferable in terms of heat resistance required when kneading with a polyether ester or the like. . Even more surprisingly, the use of anionic surfactants such as alkyl sulfonates and alkyl benzene sulfonates as the anionic surfactant markedly increases the antistatic effect and makes the effect permanent. To last. It is presumed that such a sulfonate contributes to the improvement of the effect by using in combination with the acid component represented by the formula (1), which constitutes the polyether ester.

As the alkyl sulfonate, sodium dodecyl sulfonate, potassium dodecyl sulfonate,
Examples thereof include sodium decyl sulfonate, potassium decyl sulfonate, sodium cetyl sulfonate, potassium cetyl sulfonate, and mixtures thereof. Examples of alkylbenzene sulfonates include sodium dodecylbenzene sulfonate, potassium dodecylbenzene sulfonate, sodium decylbenzene sulfonate, potassium decylbenzene sulfonate, sodium cetylbenzene sulfonate, potassium cetylbenzene sulfonate, and mixtures thereof. Etc. can be mentioned.

The surfactant in the resin composition of the present invention is 0 parts by weight of the surfactant (C) based on 100 parts by weight of the acrylic resin (A) and 5 to 30 parts by weight of the polyether ester (B). 0.5 to 6 parts by weight. If the amount is less than 0.5 parts by weight, the effect of adding the surfactant will not be exhibited, and if it exceeds 6 parts by weight, the physical properties will be deteriorated and the handleability will be deteriorated. The content of the surfactant (B) is preferably 0.7 to 5 parts by weight, more preferably 1 to 4 parts by weight.

The antistatic resin composition of the present invention is produced by melt-mixing the above acrylic resin (A), polyether ester (B) and surfactant (C) by a conventionally known method. You can Examples of the melt mixing method include a method in which the constituent components of the resin composition of the present invention are melt mixed using a uniaxial or biaxial melt extruder.

Constituent components (A) and (B) of the above resin composition
Although (C) and (C) may be melt mixed at the same time, the polyether ester (B) and the surfactant (C) are previously mixed.
Melt and mix, then add this and acrylic resin (A)
By melt-mixing and, it is possible to obtain an antistatic acrylic resin composition that exerts a permanent antistatic effect and is less likely to deteriorate transparency, physical properties, moldability, and heat resistance.

As a method of melt-mixing the polyether ester (B) and the surfactant (C) in advance, for example, after the completion of the polymerization reaction of the polyether ester, the above surfactant is directly added to the polymerization tank and mixed. , Melt-mixing with acrylic resin (A), polyether ester (B) using uniaxial or biaxial melt extruder
And a surfactant (C) are mixed, and an acrylic resin (A)
And a method of melt mixing. The temperature at which the polyether ester (B) and the surfactant (C) are melt-mixed is generally 140 ° C to 300 ° C. 140
If the temperature is lower than ℃, mixing may not be sufficient.
When the temperature is higher than 00 ° C., it may cause deterioration such as decomposition, which is not preferable. The melt mixing temperature is preferably 160
℃ to 270 ℃, more preferably 200 ℃ to 2
It is 60 ° C.

The mixture of the thus obtained (B) and (C) is further melt-mixed with the acrylic resin (A) at 200 ° C. to 300 ° C. to obtain the antistatic acrylic resin composition of the present invention. You can Such mixing can be carried out using a single or twin screw melt extruder. At this time, if the temperature is lower than 200 ° C, the mixing may not be sufficient, and if the temperature is higher than 300 ° C, deterioration such as decomposition may occur, which is not preferable. The melt mixing temperature is preferably 220 ° C to 290 ° C, more preferably 230 ° C to 280 ° C.

The antistatic acrylic resin composition of the present invention may contain various additives as required.
Such additives include glass fiber, metal fiber, aramid fiber, ceramic fiber, potassium whisker titanate, carbonic acid fiber, fibrous reinforcing agent such as asbestos, talc, calcium carbonate, mica, clay, titanium oxide, aluminum oxide, Various fillers such as glass flakes, milled fibers, metal flakes and metal powders, heat stabilizers or catalyst deactivators represented by phosphoric acid esters and phosphorous acid esters, oxidation stabilizers, light stabilizers, lubricants , Pigments,
Additives such as flame retardants, flame retardant aids, plasticizers and the like can be mentioned.

[0047]

According to the present invention, by mixing a polyether ester containing a specific aromatic dicarboxylic acid component nucleus-substituted with a sulfonate group and a surfactant with an acrylic resin, It is possible to obtain an acrylic resin composition that exhibits a high antistatic effect permanently without impairing the mechanical properties of the acrylic resin and has excellent transparency.

Therefore, such a resin composition is useful for OA equipment, electronic members, automobile housings, medical members, various containers, covers, films, sheets and the like.

[0049]

EXAMPLES The preferred embodiments of the present invention will be described below with reference to examples, but the present invention is not limited to the examples.

In the examples, "part" means "part by weight".
The reduced viscosity is a value measured at 35 ° C. at a concentration of 1.2 (g / dl) in a mixed solvent of phenol / tetrachloroethane (weight ratio 60/40) unless otherwise specified. The refractive index was measured with an Abbe refractometer (manufactured by Atago Co., Ltd.). Impact strength is 1 / according to ASTM D256
8 inches, heat distortion temperature (HDT) ASTM D64
8 was measured at 1/8 inch and a load of 18.6 kg / cm ² . The surface resistivity is measured at 20 ° C and humidity of 60
%, After applying for 24 hours under a condition of 10%, an applied voltage of 10 using a super insulation meter (SM-8210 manufactured by Toa Denpa Kogyo Co., Ltd.)
It was measured at 00V. The molded product was washed with running water at 30 ° C. for 2 hours, and the water was wiped off with clean paper. Then, it dried under the same conditions and the surface specific resistance was measured. Regarding the light transmission (transparency) of molded products, JIS
According to Z 8703, the lightness index L in the Hunter color difference formula was measured and evaluated by the transmission method. A Z-300A manufactured by Nippon Denshoku Industries Co., Ltd. was used for the measurement, and the sample thickness was 2 mm.
Was measured by the transmission method.

Reference Example 1 370 parts of dimethyl terephthalate, 222 parts of dimethyl 5-sodium sulfoisophthalate, 413 parts of 3-methyl-1,5-pentanediol, 1625 parts of polyethylene glycol (number average molecular weight 2000), And 1.1 parts of tetrabutyl titanate were placed in a reactor equipped with a rectification column and a stirrer, and the inside of the vessel was replaced with nitrogen, and then the temperature was raised to 220 ° C. under normal pressure. Two
After performing the reaction for 5 hours while distilling off methanol at 20 ° C., the reaction product was placed in a reactor having a vacuum distillation system equipped with a stirring device, and the temperature was raised to 240 ° C. in 45 minutes. At that time, the pressure in the reaction system was gradually reduced to 0.3 mmHg after 60 minutes, and a polymer was obtained after 6 hours. The reduced viscosity of the obtained polyether ester was 0.57. Further there,
After adding 464 parts of sodium dodecylbenzenesulfonate and replacing the inside of the container with nitrogen, the mixture was stirred at 240 ° C. under reduced pressure for 1 hour. The refractive index of the obtained mixture was 1.50.

Reference Example 2 577 parts dimethyl terephthalate, 155 parts dimethyl 5-sodium sulfoisophthalate, 578 parts 1,6-hexamethylene glycol, 922 parts polyethylene glycol (number average molecular weight 2000), and 1 2 parts of tetrabutyl titanate was placed in a reactor equipped with a rectification column and a stirrer, the inside of the vessel was replaced with nitrogen, and then the temperature was raised to 220 ° C. under normal pressure. 220 ° C
After the reaction was carried out for 5 hours while distilling methanol off at 4, the reaction product was placed in a reactor having a vacuum distillation system equipped with a stirring device, and the temperature was raised to 240 ° C. in 45 minutes. At that time, the pressure inside the reaction system was gradually reduced, and after 60 minutes, the pressure was adjusted to 0.3 mmHg, and 6
A high viscosity polymer was obtained after time. The reduced viscosity of the obtained polyether ester was 1.12. Further, 369 parts of sodium dodecylbenzenesulfonate was added thereto, and the inside of the container was replaced with nitrogen, and then the mixture was stirred at 240 ° C. under reduced pressure for 1 hour. The refractive index of the obtained mixture was 1.51.

[Examples 1 and 2] Polymethylmethacrylate (PMMA) resin ("Delpet" manufactured by Asahi Kasei Corporation)
80 N, refractive index 1.49) to 100 parts of the mixture of the polyether ester and the surfactant obtained in Reference Examples 1 and 2, respectively, the indicated amount, 30 mmφ co-rotating twin-screw extruder (Ikegai Tekko Co., Ltd., PCM3
0) was melt-kneaded under the conditions of a polymer temperature of 250 ° C. and an average residence time of about 3 minutes, and pelletized. Next, using an injection molding machine (M-50B manufactured by Meiki Seisakusho Co., Ltd.), injection molding was performed at a cylinder temperature of 250 ° C. and a mold temperature of 50 ° C. to obtain a molded product having a thickness of 2 mm, and measurement of surface resistivity. I went. The results are shown in Table 1 together with mechanical properties and brightness index.
Shown in

[Comparative Example] Polymethylmethacrylate (P
MMA) resin (Asahi Kasei "Delpet" 80
N) is an injection molding machine (M-50B manufactured by Meiki Seisakusho Co., Ltd.)
Was used for injection molding at a cylinder temperature of 250 ° C. and a mold temperature of 50 ° C. to obtain a molded product having a thickness of 2 mm, and the surface resistivity was measured. The results are shown in Table 1 together with the mechanical properties.

[0055]

[Table 1]

Claims (4)

[Claims] 1. An acrylic resin (A) 100 parts by weight,
(B1) C6-20 dicarboxylic acid and / or ester thereof, (B2) number average molecular weight 200 to 50,000
Of poly (alkylene oxide) glycol, and (B
3) A resin composition comprising 5 to 30 parts by weight of a polyether ester (B) obtained by polycondensing a glycol having 2 to 10 carbon atoms and 0.5 to 6 parts by weight of a surfactant (C). The above (B1) is represented by the following formula (1): [In the formula (1), Ar is a trivalent aromatic group having 6 to 12 carbon atoms, R ¹ and R ² are each independently a hydrogen atom, 1 to 1 carbon atoms.
6 represents an alkyl group having 6 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and M ⁺ represents a metal ion, a tetraalkylphosphonium ion or a tetraalkylammonium ion. ]
The aromatic dicarboxylic acid and / or its ester (B1 ′) substituted with a sulfonate group of 3 to 50 mol% is contained, and the content of the above (B2) constituting the above polyether ester (B) is Within the range of 10 to 90% by weight of the total amount of (B1), (B2) and (B3),
Moreover, the difference between the refractive index of the acrylic resin (A) and the refractive index of the mixture of the polyether ester (B) and the surfactant (C) is 0.03 or less. Preventing acrylic resin composition. 2. The reduced viscosity (concentration: 1.2 g / d) of the polyether ester (B) measured at 35 ° C. in a mixed solvent of phenol / tetrachloroethane (weight ratio 60/40).
The antistatic acrylic resin composition according to claim 1, wherein l) is 0.3 or more. 3. The antistatic acrylic resin according to claim 1, wherein the surfactant (C) is at least one ionic surfactant selected from the group consisting of alkyl sulfonates and alkylbenzene sulfonates. Resin composition. 4. The polyether ester (B) according to claim 1 is melt-mixed with the surfactant (C) and then further melt-mixed with the acrylic resin (A). The method for producing the antistatic acrylic resin composition according to any one of claims.