KR0167049B1 - Thermoplastic resin composition - Google Patents

Abstract

The present invention relates to a thermoplastic resin composition, wherein an ethylene structural unit (80 to 98 mol%), an acrylate structural unit (1 to 15 mol%) and an acrylamide structural unit (2 to 20 mol%) are arranged in a linear shape It is obtained by blending a cationic copolymer having a weight average molecular weight of 1,000 to 5,000 to a (meth) acrylic resin, and is suitably used for moldings having three-dimensional three-dimensional structures such as casings and containers, such as home appliance parts. It is characterized by excellent properties such as permanent antistatic property, water resistance and wear resistance.

Description

Thermoplastic Composition

Industrial Applicability The present invention is suitably used for moldings having three-dimensional three-dimensional structures such as materials such as home appliance parts, in particular, k-types, containers, and the like, for thermoplastic resin compositions having excellent properties such as permanent antistatic property, water resistance, and friction resistance. It is about.

Thermoplastic resins have conventionally been widely used in materials such as packaging materials, lighting equipment, home appliance parts, and instrument covers. However, molded articles made of thermoplastic resins such as (meth) acrylic resins and polystyrene resins generally have high electrical resistance, have a significant drawback of being easily charged by friction, and attracting dust and the like.

In recent years, the following method has been proposed as a method of imparting antistatic ability to the thermoplastic resin. That is, a method of applying an antistatic agent to a resin surface and drying the method of adding an internal additive type antistatic agent to the resin, a method of applying a silicone compound to the resin surface, and a method of modifying the resin itself have been proposed.

In the method (1), a surfactant solution is used as an antistatic agent. However, since such an antistatic agent is easily removed from the resin surface by washing and friction, it cannot be given a permanent antistatic ability.

In the method of (2) above, for example, glycerin fatty acid ester, sorbitan fatty acid ester, alkyl diethanolamide, alkylbenzenesulfonate, quaternary salt of alkylimidazole, etc. are used as the internal antistatic agent. Even if it is removed from the resin surface by washing, the antistatic ability lasts for a relatively long time because it bleeds to the resin surface in order.

However, if the antistatic ability is required for a long time to recover, and if the antistatic agent is excessively bleeded, the resin surface may become tacky and easily adhere to dust or the like. This causes a problem of deterioration of printing characteristics and deterioration of appearance on the resin surface.

Moreover, since these antistatic agents have a small molecular weight, they are volatilized by the heat at the time of shaping | molding at high temperature. As a result, there have been problems such as economic disadvantages in which an antistatic agent must be added more than necessary and difficulty in adjusting an effective amount of the antistatic agent.

As a solution to the above-described internal addition antistatic agents, polymethyl methacrylate (Japanese Patent Publication No. 89-170603) and alkoxypolyethylene glycol methacrylate in which 20 to 80 mol% of methoxy groups have recently been modified with diethanolamine Graft copolymer (Japanese Patent Publication No. 83-39860), polymerized by quaternization after imide-modification of styrene maleic anhydride copolymer (Japanese Patent Publication No. 89-29820), polymethylmethacryl Comb copolymer of a high molecular weight monomer obtained by converting a terminal carboxyl group of a rate into a glycidyl methacrylate to a methacryloyl group and an aminoalkyl acrylic acid ester or acrylamide and its quaternized cationic modified product (Japanese Patent Publication No. 87- A high molecular compound having an antistatic functional group such as 121717 has been proposed as an internal additive antistatic agent.

Similarly, ethylene-acryloylaminoalkyltrialkylammonium salt copolymer (molar ratio 65-99 / 1-35) and ethyleneacryloylaminoalkyltrialkylammonium salt-acrylic acid ester copolymer (molar ratio 65-99 / 1-35 / It is disclosed to obtain an antistatic film by inserting 0 to 15 into thermoplastic resins such as polyethylene, polypropylene, polyester, and polyamide (Japanese Patent Laid-Open No. 93-5066).

However, there is no problem in the case of forming a film on a film or sheet with the composition having the above composition, but when applied to a molded body having a three-dimensional three-dimensional structure such as a storage case, in terms of mechanical properties such as water resistance, friction resistance, impact strength, etc. There was a problem in practical use. Moreover, there also existed a problem in which transparency of the said molded object falls.

In addition, Japanese Patent Application Laid-Open No. 93-78543 discloses a method of obtaining a permanent antistatic composition having transparency, and a method of adding an electrolyte to a polyethylene glycol derivative having a specific composition. However, durability and heat resistance of the resin composition obtained therefrom are shown. Not satisfactory and not practical.

Although the resin composition in which the antistatic ability lasts semipermanently can not be obtained by the method of the above ③, it is very disadvantageous in terms of price because the silicon compound used is expensive and the working efficiency is poor.

In addition, although the method of (4) is a method of introducing a hydrophilic group into resin, it is necessary to introduce a considerable amount of hydrophilic group in order to provide sufficient antistatic ability. However, when a large amount of hydrophilic groups were introduced into the resin, the resin itself lowered the hygroscopicity and the mechanical properties.

As described above, the conventional thermoplastic resin composition which is said to have antistatic property is still insufficient in antistatic ability, its durability, water resistance, mechanical properties, and the like.

The present invention has been carried out in view of the above-mentioned drawbacks of the prior art, and its object is a thermoplastic resin composition which can be obtained by adapting to a molded article having a three-dimensional solid structure which has excellent permanent antistatic performance and also has excellent properties such as water resistance and mechanical properties. To provide.

The thermoplastic resin composition of the present invention is a resin composition obtained by adding (meth) acrylic resin or polystyrene resin as a matrix resin and adding the following cationic copolymer thereto.

That is, the (meth) acrylic resin composition of the invention comprises (A) (meth) acrylic resin and (B) 80 to 98 mol% of ethylene structural units represented by formula (I) and acrylamide structure represented by formula (III) It consists of the cationic copolymer of the weight average molecular weights 1,000-50,000 formed by arrange | positioning 2-20 mol% of units linearly.

(Wherein, R ² is an ethylene group or a propylene group, R ³ and R ⁴ is a methyl group, R ⁵ is a straight chain alkyl group or arylalkyl group, each having 1 to 8 carbon atoms X ^- is a halide ion, CH ₃ OSO ₃ ^- or CH ₃ CH ₂ OSO ₃ ⁻ , and R ² may be the same or different for each structural unit.)

Moreover, the (meth) acrylic-type resin composition of this invention is 80-98 mol% of (A) (meth) acrylic-type resin and (B) ethylene structural unit represented by Formula (I), and the acrylate structure represented by Formula (II). A cationic copolymer having a weight average molecular weight of 1,000 to 50,000 consisting of 15 mole% or less (0 mole% is not included) and 2 to 20 mole% of acrylamide structural units represented by formula (III). Is made of.

(Wherein R ¹ is a methyl group or an ethyl group, R ² is an alkylene or propylene group, R ³ and R ⁴ are a methyl group, R ⁵ is a linear alkyl group or an arylalkyl group having 1 to 8 carbon atoms, X ⁻ is a halide ion, CH ₃ OSO ₃ ^- or CH ₃ CH ₂ OSO ₃ ^- and R ^{1 and} R ² may be the same or different for each structural unit.)

The polystyrene resin composition of the present invention comprises (A) 70 to 97% by weight of polystyrene resin and (B) 80 to 98 mol% of the ethylene structural unit represented by the formula (I) and acrylamide represented by the formula (III) It consists of 3-30 weight% of cationic copolymers of the weight average molecular weights 1,000-50,000 formed by arrange | positioning 2-20 mol% of structural units linearly.

In addition, the polystyrene resin composition of the present invention is represented by (A) 70 to 97% by weight of polystyrene resin and (B) 80 to 98 mol% of the ethylene structural unit represented by the formula (I) and the formula (II). The weight average molecular weight 1,000-50,000 which is 15 mol% or less (0 mol% is not included) and 2-20 mol% of acrylamide structural units represented by said Formula (III) are arranged linearly. It consists of 3-30 weight% of cationic copolymers of the.

Moreover, each structural unit (I)-(II) may be arrange | positioned regularly, and may be arranged irregularly.

[Matrix Resin (A)]

In the resin composition of the present invention, (meth) acryl resin and polystyrene resin are used as the matrix resin (A), but the type of each resin is not particularly limited.

As a specific example of (meth) acrylic-type resin, polymethyl methacrylate, ethyl polymethacrylate, propyl polymethacrylate, butyl polymethacrylate, methyl polyacrylate, ethyl polyacrylate, methyl methacrylate-methyl acrylate copolymer, Alkyl, such as methyl, ethyl, propyl, and butyl of (meth) acrylic acid, such as methyl methacrylate-ethyl methacrylate copolymer, methyl methacrylate-butyl methacrylate copolymer, and methyl methacrylate-ethyl acrylate copolymer Homopolymers or copolymers of ester compounds; and the like. These acrylic resins may be used alone or in combination of two.

The production method is not particularly limited, and known suspension polymerization methods, emulsion polymerization methods, bulk polymerization methods and the like can be used.

Although it does not specifically limit as a weight average molecular weight of said (meth) acrylic-type resin, 10,000-500,000 are preferable and 20,000-300,000 are more preferable.

Specific examples of the polystyrene resin include copolymerization of styrene such as styrene butadiene copolymer, methyl methacrylate-styrene copolymer, styrene-acrylonitrile copolymer and styrene-methyl methacrylate-butadiene copolymer in addition to styrene homopolymer. The copolymer which has as a component is mentioned. However, copolymers in which styrene, acrylonitrile and butadiene coexist in the same molecule are excluded.

Moreover, the transparent styrene resin composition of this invention can be obtained by using the polystyrene resin which has a refractive index of the range similar to the refractive index (typically 1.47-1.52) of a cationic copolymer (B). In this case, it is preferable to select a cationic copolymer or polystyrene resin so that the difference of the refractive index of a cationic copolymer (B) and the refractive index of a polystyrene resin (A) may be 0.02 or less.

For example, styrene is 59.5 mol% or less in the styrene-nethyl acrylate copolymer resin, or styrene is 58 mol% or less in the styrene-ethyl acrylate copolymer resin, and styrene-methyl methacrylate copolymer resin Styrene resin having a refractive index of 1.45 to 1.54 can be obtained when the styrene is 49 mol% or less, and the styrene resin having both permanent antistatic properties and transparency by blending the styrene resin and the cationic copolymer in a predetermined ratio. A composition can be obtained.

Although it does not specifically limit as a weight average molecular weight of polystyrene resin, 10,000-500,000 are preferable and 20,000-300,000 are more preferable.

Cationic Copolymer (B)

The structure of the cationic copolymer (B) used in the resin composition of this invention is demonstrated in detail below.

In the cationic copolymer (B) used in the present invention, the ethylene structural unit represented by the general formula (I) contains 80 to 90 mol% in the molecule. If the content ratio of the ethylene structural unit (I) is less than 80 mol%, the compatibility with the matrix resin (A) is deteriorated, and the water resistance and mechanical properties of the molded body are significantly reduced. In addition, when the content ratio exceeds 98 mol%, sufficient antistatic capability cannot be obtained. From the viewpoint of compatibility and antistatic ability, a preferable range of the content ratio of ethylene structural unit (I) is 85 to 97.5 mol%.

In addition, the acrylate structural unit represented by general formula (II) contains 0-15 mol% in a molecule | numerator. By containing this acrylate structural unit (II), the compatibility of a matrix resin (A) and a cationic copolymer (B) improves.

When the content rate of the acrylate structural unit (II) exceeds 15 mol%, mechanical properties deteriorate. From the viewpoint of compatibility, a preferable range of the content ratio of the acrylate structural unit (II) is 0.0001 to 13 mol%, more preferably 1 to 13 mol%, and still more preferably 3 to 13 mol%.

In General Formula (II), R ¹ represents a methyl group or an ethyl group, and R ¹ may be the same or different for each structural unit (that is, a methyl group and an ethyl group may be common in one molecule),

The acrylamide structural unit represented by the general formula (III) is a cationic structural unit in the form of a quaternary ammonium salt and contains 2 to 20 mol% in the molecule.

If the content ratio is less than 2 mol%, the antistatic ability of the resin composition is poor, and if the content ratio exceeds 20 mol%, the cationic copolymer (B) has no compatibility with the matrix resin (A). Worsens. From the viewpoint of antistatic ability and compatibility, the preferred content of acrylamide structural unit (III) is 2.5 to 15 mol%.

In formula (III), R ² represents an ethylene group or a propylene group, and these may be common in one molecule, R ³ and R ⁴ represent a methyl group, and R ⁵ represents ease of manufacture and good antistatic ability. methyl group at that point of view, represents an alkyl group of a straight chain lower (having 1 to 8 carbon atoms) or a benzyl group agree arylalkyl groups such as ethyl group, X ^- is a C1 ^-, Br ^-, I ^- a halide ion such as, CH ₃ OSO ₃ ^- Or CH ₃ CH ₂ OSO ₃ ⁻ .

The above-mentioned main weight average molecular weight of the cationic copolymer (B) is the weight average molecular weight of polystyrene in terms of gel permeation chromatography, and the measurement is carried out by ultra-high temperature GPC method (Juncheon), "Polymer Paper Vol. 44, No. 2" , Pp. 139 to 141, 1987). The range of the weight average molecular weight of a cationic copolymer (B) is 1,000-50,000.

If the weight average molecular weight is less than 1,000, the cationic copolymer (B) becomes waxy, the handling property is deteriorated, and the tackiness of the resin surface is increased by bleeding out, and the weight average molecular weight is 50,000. If it exceeds the problem occurs that the compatibility with respect to the matrix resin (A) is deteriorated. The preferable range of the weight average molecular weight of the said copolymer (B) is 3,000-30,000.

As a manufacturing method of the cationic copolymer (B) used in the resin composition of this invention, the ethylene-acrylic acid ester copolymer obtained by copolymerizing ethylene and an acrylic acid ester by a high pressure polymerization method, for example is Unexamined Japanese Patent Publication. By hydrolysis at the same time as the method described in 85-79008, the desired molecular weight, and the obtained ethylene-acrylic acid ester-acrylic acid copolymer is amidated with N, Ndialkylaminoalkylamine and then known 4 Although the method of obtaining the said cationic copolymer (B) by modifying and separating cation with a catalytic agent is mentioned, it is not limited to this.

Although the amount of the cationic copolymer (B) added to the matrix resin (A) in the resin composition of the present invention is practically 3 to 30% by weight, when the amount is less than 3% by weight, the required antistatic properties are required. On the contrary, when the addition amount exceeds 30% by weight, the mechanical properties of the resin, in particular, the impact strength are lowered.

The amount of the cationic copolymer (B) added to the matrix resin (A) is preferably 5 to 30% by weight in view of the balance between the antistatic properties and the mechanical properties in the resin composition.

As a method for producing the resin composition of the present invention, the cationic copolymer (B) may be added to the matrix resin (A) by a known method such as a twin screw extruder.

Nonionic or cationic surfactants, polymers having polyoxyethylene chains, for example, high molecular weight or urethane bonds, epoxy ester bonds, polycondensation of polyoxyethylene and polyethylene glycol with ester bonds, amide bonds, imide bonds, The antistatic agent of the high molecular weight added by the epoxy ether bond may be added simultaneously in the range not exceeding the addition amount of the cationic copolymer (B) of the present invention.

Furthermore, bromine-containing flame retardants and phosphorus compound-containing flame retardants such as inorganic fillers such as calcium carbonate, talc and glass fibers, hexabromocyclododecane, tetrabromobispetol (A) and derivatives thereof, and bromide of diphenyl ether And flame retardant aids such as Sb ₂ O ₃ may be added at the same time.

The cationic copolymer (B) added in the resin composition of the present invention forms a continuous layer in the matrix resin (A) and is used to transfer charges accompanying the movement of ions to the cation group in the copolymer (B) aliquot. This causes leakage of static electricity. Accordingly, the cationic copolymer (B) has a higher rate of static electricity leakage than the conventional internally-added antistatic agent which leaks the generated static electricity by a moisture absorbing layer formed by bleeding out of the resin surface. .

Further, in the resin composition of the present invention, since the cationic copolymer (B) does not exist at a high concentration near the surface of the resin which is easily influenced by the external agent, it achieves a number of significant effects as described below.

(1) The resin composition of the present invention is a resin composition having excellent permanent antistatic property without causing loss of antistatic effect due to friction or washing with water on the surface. In addition, when a conventional antistatic agent is used, the resin composition of the present invention maintains an antistatic ability at a high level even under severe conditions (such as molding processing at high temperature) where the effect is lost.

(2) In the resin composition of the present invention, there is no problem that adhesiveness occurs on the resin surface due to excessive bleed-out as in the case of using a conventional internal additive type antistatic agent, and thus, dust or the like is easily attached.

(3) Permanent to the (meth) acrylic resin molding or the polystyrene resin molding by blending and molding the cationic copolymer (B) in the matrix resin (A) made of (meth) acrylic resin or polystyrene resin. The antistatic property can be imparted and the friction resistance of the molded body can be improved. That is, the cationic copolymer (B) acts as a friction resistance improver having antistatic ability imparting ability to the matrix resin (A). This action is remarkable when the blending ratio of the cationic copolymer to the matrix resin is 3 to 30% by weight.

(4) Furthermore, by blending and molding the cationic copolymer (B) in the matrix resin (A), it is possible to impart permanent antistatic property to the (meth) acrylic resin molded article or the polystyrene resin molded article and the molded article. Can improve the impact strength. That is, the cationic copolymer (B) acts as an impact strength enhancer having an antistatic imparting capability to the matrix resin (A). This action is remarkable when the blending ratio of the cationic copolymer to the matrix resin is 3 to 30% by weight.

(5) Furthermore, by blending and molding the cationic copolymer (B) in the matrix resin (A), it is possible to impart permanent antistatic property to the (meth) acrylic resin molded article or the polystyrene resin molded article, Water resistance can be improved. That is, the cationic copolymer (B) acts as a water resistance improver having an antistatic imparting ability to the matrix resin (A). This action is remarkable when the blending ratio of the cationic copolymer to the matrix resin is 3 to 30% by weight.

(6) Even when the resin composition of the present invention is molded into a molded article having a three-dimensional three-dimensional structure such as an article storage case or a container, the molded article has excellent impact resistance, friction resistance, elongation, water resistance, and the like.

(7) Moreover, in the molded object which consists of resin compositions, transparency of the used matrix resin itself can also be fully maintained. In other words, the molded article having the permanent antistatic property and excellent transparency can be obtained by the resin composition of the present invention.

About the said transparency, since the refractive index of a cationic copolymer (B) shows about 1.47-1.52 and is very close to the refractive index of (meth) acrylate type resin, the molded object which consists of obtained resin composition is equipped with the outstanding transparency. For reference, the refractions of methyl methacrylate, ethyl methacrylate, i-propyl methacrylate and tert-butyl methacrylate are 1.489, 1.485, 1.4728 and 1.4638, respectively.

EXAMPLE

First, the specific synthesis example of the cationic copolymer (B) used in this invention is demonstrated.

[Synthesis example (B-1) of a cationic copolymer (B)]

400 ml of xylene, 150 g of ethylene-ethyl acrylate-acrylic acid copolymer (ethylene / ethyl acrylate / acrylic acid = 93/3/4) and paratoluene in a four-liter flask equipped with thermometer, stirrer, dropping lot and Dean-Stark fountain 1.0 g of sulfonic acid was added.

Next, 21.1 g of N, N-dimethylaminopropylamine was added thereto, heated at 140 ° C using an oil bath, and the produced water was continuously removed for 17 hours while being continuously removed by azeotroping with xylene. The amidation reaction was continued until the azeotrope of water was not confirmed.

458 g of the reaction product thus obtained was cooled to 80 ° C, and 31.1 g of diethyl sulfate was slowly added dropwise thereto over 1 hour through a dropping funnel. The exotherm was confirmed during this time, but as it cooled, the reaction temperature was maintained at 90 ° C., and after completion of the dropwise addition, the aging reaction was performed at 100 ° C. for 4 hours.

The reaction product obtained here was thrown into a large amount of methanol, the produced | generated deposit was collect | recovered and dried, and the cationic copolymer (B-1) was obtained. The weight average molecular weight of the copolymer (B-1) was measured and found to be 5,300.

[Synthesis example of cationic copolymer (B) (B-2)]

In a four-liter flask equipped with a thermometer, a stirrer, a dropping lot, and a Dean-Stark fountain, 400 ml of xylene, 150 g of ethyl ethylene acrylate copolymer (ethylene / acrylic acid = 91/9), and 1.0 g of paratoluene sulfonic acid were added.

Next, 38.5 g of N, N-dimethylaminoethylamine was added thereto, heated at 140 ° C. using an oil bath, and the produced water was continuously removed for 17 hours while being continuously removed by azeotroping with xylene. The amidation reaction was continued until the azeotrope of water was not confirmed.

The obtained reactant was cooled to 80 degreeC, and 72.0 g of methyl iodide was dripped there over 1 hour. The exotherm was confirmed during this time, but as it cooled, the reaction temperature was maintained at 90 ° C., and after completion of the dropwise addition, the aging reaction was performed at 100 ° C. for 4 hours.

The reaction product obtained here was thrown into a large amount of n-hexane, the produced | generated deposit was collect | recovered and dried, and the cationic copolymer (B-2) was obtained. It was 22,000 when the weight average molecular weight of the said copolymer (B-2) was measured.

[Synthesis example (B-3) of a cationic copolymer (B)]

400 ml of xylene, 150 g of ethylene-ethyl acrylate-acrylic acid copolymer (ethylene / ethyl acrylate / acrylic acid = 93/3/4) and paratoluene in a four-liter flask equipped with thermometer, stirrer, dropping lot and Dean-Stark fountain 1.0 g of sulfonic acid was added.

Next, 21.1 g of N, N-dimethylaminopropylamine was added thereto, heated at 140 ° C using an oil bath, and the produced water was continuously removed for 17 hours while being continuously removed by azeotroping with xylene. The amidation reaction was continued until the azeotrope of water was not confirmed.

458 g of the obtained reactant was cooled to 80 ° C, and 25.5 g of benzyl chloride was slowly added thereto over 1 hour through a dropping funnel. The exotherm was confirmed during this time, but as it cooled, the reaction temperature was maintained at 90 ° C., and after completion of the dropwise addition, the aging reaction was performed at 100 ° C. for 4 hours.

The reactant obtained here was put into a large amount of methanol, and the produced precipitate was collected and dried to obtain a cationic copolymer (B-3). The weight average molecular weight of the copolymer (B-3) was measured and found to be 5,500.

Comparative Example (B-4)

400 ml of xylene, 150 g of ethylene-ethyl acrylate acrylic acid copolymer (ethylene / ethyl acrylate / acrylic acid = 65/5/30) in a four-liter flask equipped with thermometer, stirrer, dropping lot and Dean-Stark fountain and para 1.0 g of toluenesulfonic acid was added thereto.

Next, 105.6 g of N, N-dimethylaminoethylamine was added thereto, heated at 140 ° C. using an oil bath, and the produced water was continuously removed by azeotroping with xylene, and the reaction continued for 17 hours. The amidation reaction continued until azeotropes were not confirmed.

The obtained reaction product was cooled to 80 degreeC, and 170.4 g of methyl iodide was dripped there over 1 hour. The exotherm was confirmed during this time, but as it cooled, the reaction temperature was maintained at 90 ° C., and after completion of the dropwise addition, the aging reaction was performed at 100 ° C. for 4 hours.

The reaction product obtained here was thrown into a large amount of n-hexane, and the produced | generated deposit was collect | recovered and dried, and the cationic copolymer (B-4) was obtained. The weight average molecular weight of the copolymer (B-4) was measured and found to be 8,600.

[Examples 1 to 12 (Preparation of (meth) acrylic resin composition)]

A twin-screw extruder equipped with (meth) acrylic resin (A) shown in [Table 1] and cationic copolymers (B-1) to (B-3) obtained in the above synthesis example with a quantitative supply device (Shinkou Kurimoto KRC Kneader-S-II) manufactured by Shosa Co., Ltd. were mixed and pushed out at the compounding ratio shown in Table 1 to obtain a composition pellet.

A test body (60 x 60 x 3 mm, 50 x 50 x 1 mm flat plate molded body and JIS K-71102 A test piece) made of the composition pellets was molded by an injection molding machine (Hipa Short 3000, manufactured by Niigata Kohsho Co., Ltd.).

Various physical property tests of the following ①-⑥ were performed using the obtained molded object. The measurement results are written together in [Table 1].

Comparative Examples 1 to 8

Instead of using cationic copolymers (B-1) to (B to 3), lauryl diethanolamine and polyether esteramides may be blended in the ratios shown in [Table 2], or the resin alone without blending at all. A molded article (test article) made of a resin composition was produced in the same manner as in the above example except that the physical properties were measured. The results are written together in [Table 2].

In addition, the test items and evaluation method of the molded body are as follows.

① Antistatic

Antistatic property was evaluated by surface specific resistance value.

The surface intrinsic resistance value measured the resistance value in the case of applying a voltage of 500V to the said molded object (test body) with the megaohmmeter (made by Toa Denpa Co., Ltd.).

② High voltage decay rate

The time required to apply half the initial voltage to 10,000 Vx30 second was applied to the said molded object (test body) by the static onest meter (made by Shishido Shoga Kaisha), and the number of seconds was shown.

③ Friction resistance

The molded body (test body) was rubbed with gauze soaked in water 80 times, dried, and the surface specific resistance value was measured in the same manner as in ①.

④ Water resistance

The molded body (test body) was boiled in boiling water for 2 hours, dried, and the surface specific resistance value was measured in the same manner as in ①.

⑤Transparency

Transparency was evaluated by haze number.

It measured using the haze meter (made by Nippon Denshoku Kogyo Co., Ltd.) using the molded object (test body) of 50x50x1 mm.

⑥Izod impact strength

Izod impact strength of the molded product (test body) was measured according to JIS K-7110.

In addition, the electrical characteristics of the above-mentioned (1)-(4) are measured after humidifying for 24 hours or more at the temperature of 20 degreeC, and 60% of a relative humidity.

A-1: Polymethyl methacrylate (weight average molecular weight 150,000)

A-2: Methyl polymethacrylate / ethyl polymethacrylate = 90 mol / 10 mol (weight average molecular weight 130,000)

A-3: Methyl polymethacrylate / polybutyl isobutyl methacrylate = 90 mol / 10 mol (weight average molecular weight 105,000)

A-1 to 3 are the same as in [Table 1].

Attica Pebox 4011

In Table 1, the (meth) acrylic resin composition obtained by adding the cationic copolymers (B-1) to (B-3) to the (meth) acrylic resin in Table 2 has antistatic properties, abrasion resistance, water resistance, It can be seen that the transparency and the impact strength are excellent.

When antistatic agents other than the cationic copolymers (B-1) to (B-3) were added to the resin, the surface intrinsic resistance of the resin was approximately equal, but the mechanical properties such as friction resistance and impact strength and water resistance were greatly reduced. .

[Examples 13 to 22 Preparation of Polystyrene Resin Composition]

The polystyrene-based resin (A) shown in [Table 3] and the cationic copolymers (B-1) to (B-3) obtained in the above synthesis example are equipped with a twin-screw extruder (manufactured by Kurimoto Iron Works, Ltd.) KRC kneader-S-II) was kneaded and extruded at 230 ° C. at the compounding ratio shown in Table 3, and then cold-covered to obtain a composition pallet.

A test body (60 x 60 x 3 mm flat plate molded body and JIS K-7110 No. 2 A test piece) consisting of the composition pallet was molded by an injection molding machine (Hyper Short 3000, manufactured by Niigata Iron Works).

Using the obtained molded object, various physical property tests of the above-mentioned (1) to (4) and (6) and appearance (appearance evaluation) were performed. The measurement results are written together in [Table 3].

[Comparative Examples 9-18]

Instead of using the cationic copolymers (B-1) to (B-3), cationic copolymers (B-4), lauline diethanolamine, or polyether esteramides were used. Various physical properties were measured at the same time as forming a molded cell made of a resin composition in the same manner as in the above example, except that the resin was used alone or not in a ratio. The results are written together in [Table 4].

GP-PS: General grade polystyrene (weight average molecular weight 180,000)

AS: acrylonitrile styrene copolymer (weight average molecular weight 165,000)

HI-PS: High impact polystyrene (manufactured by Shin-Nitetsu Chemical Co., Ltd., trade name: ethylene H-65)

MS: Methyl methacrylate copolymer (weight average molecular weight 153,000)

GP-PS, AS, HI-PS and MS are same as the documents

Styrene-based resin compositions formed by adding cationic copolymers (B-1) to (B-3) to the polystyrene resins from Tables 3 and 4 have antistatic, frictional, water and impact resistance properties. You can see that it is excellent.

When antistatic agents other than cationic copolymers (B-1) to (B-3) were added to the resin, the surface intrinsic resistance value of the resin was almost the same, but the friction resistance and the water resistance greatly decreased.

Moreover, when the acrylamide structural unit (III) exceeded 20 mol% like the cationic copolymer (B-4), the fall of impact strength and water resistance was confirmed.

Claims (5)

1. (A) (meth) acrylic-type resin and (B) 80-98 mol% of ethylene structural units represented by following formula (I), and 2-20 mol% of acrylamide structural units represented by following formula (III) are linear form. A (meth) acrylic resin composition, comprising a cationic copolymer having a weight average molecular weight of 1,000 to 50,000, which is arranged in a series. (Wherein, R ² is an ethylene group or a propylene group, R ³ and R ⁴ is a methyl group, R ⁵ is an alkyl group or an aryl group of a straight-chain shape with a carbon number of 1~8, X ^- is a halide ion, CH ₃ OSO ₃ ^- Or CH ₃ CH ₂ OSO ₃ ⁻ , and R ² may be the same or different for each structural unit. (A) (meth) acrylic resin and (B) 80-98 mol% of ethylene structural units represented by following formula (I), 15 mol% or less of acrylate structural units represented by following formula (II), and following formula (III) A (meth) acrylic resin composition comprising a cationic copolymer having a weight average molecular weight of 1,000 to 50,000 consisting of 2 to 20 mol% of acrylamide structural units represented by the linear form. (Wherein R ¹ is a methyl group or an ethyl group, R ² is an ethylene group or a propylene group, R ³ and R ⁴ are a methyl group, R ⁵ is a straight chain alkyl group or an arylalkyl group having 1 to 8 carbon atoms, and X ⁻ is a halide ion , CH ₃ OSO ₃ ^- or CH ₃ CH ₂ OSO ₃ ^- represents a, R ^1, R ² may be the same or different, each structural unit). The (meth) acrylic resin molding according to claim 1, wherein the (meth) acrylic resin composition is molded into a molded body having a three-dimensional three-dimensional structure. A cationic air having a weight average molecular weight of 1,000 to 50,000 consisting of 80 to 98 mol% of ethylene structural units represented by the following formula (I) and 2 to 20 mol% of acrylamide structural units represented by the following formula (III). 80-98 mol% of ethylene structural units represented by following formula (B) or following formula (I), 15 mol% or less of the acrylate structural unit represented by following formula (II), and the acrylamide structure represented by following formula (III) A cationic copolymer (B) having a weight average molecular weight of 1,000 to 50,000 consisting of 2 to 20 mol% of units arranged in a linear shape is blended with the (meth) acrylic resin (A) and molded. Method for improving the impact strength of (meth) acrylic resin moldings. (Wherein R ¹ is a methyl group or an ethyl group, R ² is an ethylene group or a propylene group, R ³ and R ⁴ are a methyl group, R ⁵ is a straight chain alkyl group or an arylalkyl group having 1 to 8 carbon atoms, and X ⁻ is a halide ion , CH ₃ OSO ₃ ^- or CH ₃ CH ₂ OSO ₃ ^- represents a, R ^1, R ² may be the same or different, each structural unit). The (meth) acrylic resin molding according to claim 2, wherein the (meth) acrylic resin composition is molded into a molded body having a three-dimensional three-dimensional structure.