JP2007016181A - Resin composition excellent in antistaticity - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop a resin composition having excellent antistaticity, impact resistance, and rigidity in a highly balanced manner, without losing moldability, colorability, nor lightweight properties inherent in a styrene-based resin, having practical heat resistance, and capable of especially giving the excellent antistaticity to an extrusion molded product, and to enable the resin composition to be practically used as a raw material for an electronic part transporting material, etc. <P>SOLUTION: This resin composition comprises a rubber-reinforced styrene-based resin (A), a polyolefin-polyether block copolymer (B), and polytetrafluoroethylene (C), wherein the components (A), (B), and (C) are contained in weight ratios satisfying (numerical formula 1) to (numerical formula 3) as follows: (numerical formula 1); 0.80≤(A)/ä(A)+(B)}≤0.95, (numerical formula 2); 0.05≤(B)/ä(A)+(B)}≤0.20, and (numerical formula 3); 0.0005≤(C)/ä(A)+(B)}≤0.015. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a resin composition that imparts sustained antistaticity to a styrene resin that is inherently insulating, and has excellent antistaticity and various molding methods that cannot be achieved with conventional resin compositions. The present invention relates to a resin composition that has both fluidity, high balance of impact strength and elastic modulus, and practical heat distortion temperature, and is excellent in antistatic properties in extruded products. The resin composition of the present invention is preferably used for applications that play a role of electrically and physically protecting the contents, such as electronic parts carrying materials.

Styrenic resins are used in many industrial fields by taking advantage of their ease of molding, free coloring, and light weight. On the other hand, there is an industrial field that cannot be used because it is insulating.
Techniques for imparting antistatic properties to styrene resins include (1) a method of adding an anionic, cationic, amphoteric or nonionic surfactant as an antistatic agent, and (2) a conductive filler. There is a method of adding carbon black or a metal oxide, and (3) there is also a technique for imparting antistatic properties to a resin molded product by applying an antistatic agent or printing with a conductive ink. However, since the method (1) is based on the principle that an antistatic agent having poor compatibility with the styrene resin is physically kneaded and the antistatic agent oozes out to the surface, the antistatic agent The amount of added is limited and the antistatic stability is lacking. In addition, since the method (2) is black or a large amount of conductive filler having a high specific gravity is added, the coloration and lightness are lost. Furthermore, in the technique (3), coating and printing are additional steps, and it is difficult to lose antistatic properties due to surface friction during cleaning and use.

In addition to these, as a conventional technique for imparting antistatic properties to a styrene resin, a sustained antistatic resin composition comprising a rubber-reinforced styrene resin, a polyether ester amide, and a carboxyl group-containing vinyl polymer is known. (For example, Patent Document 1). In addition to adding hydrophilic polyether ester amide as an antistatic agent, it retains properties such as impact strength and moldability, and a carboxyl group-containing vinyl polymer is used as a compatibilizing agent to avoid delamination. It relates to the technology to be added. However, the antistatic property and physical properties and moldability of the technology are extremely insufficient, and the antistatic property is low because it is necessary to suppress the amount of polyether ester amide in order to keep the physical properties and moldability high. On the other hand, when the amount of polyether ester amide is increased to improve antistatic properties, there is a problem that physical properties and moldability are lowered. That is, the resin composition is a resin composition having excellent physical properties and moldability as long as it is dust-proof for household electrical appliances and has a surface resistivity of 10 ¹¹ to 10 ¹² Ω / □. However, in the case where antistatic properties with a surface resistivity of 10 ¹⁰ Ω / □ or less are required as in the case of electronic parts carrying materials, the resin composition has to be inferior in physical properties and moldability.

Further, as a prior art, there is known a sustained antistatic resin composition comprising a block copolymer in which a polyolefin block and a polymer block having a polyoxyalkylene main structure are alternately and repeatedly bonded (for example, patents) Reference 2). This relates to the technology of an antistatic agent comprising a polyolefin block compatible with an olefin resin and a hydrophilic polyether block, and a resin composition technology in which the antistatic agent is added to a styrene resin. It is about. However, since the polyolefin / polyether block copolymer and the styrene resin are poorly compatible, the antistatic property and physical properties of the resin composition are extremely insufficient. -When the amount of the polyether block copolymer is increased, the physical properties become extremely low, resulting in delamination. It can be used for applications that require anti-static properties with a surface resistivity of 10 ¹⁰ Ω / □ or less and high impact strength and elastic modulus to physically protect the contents, such as materials for electronic parts. Have difficulty. Here, Patent Document 2 uses a polyolefin-polyether block copolymer and a vinyl polymer modified with a carboxyl group or the like as a compatibilizer for a styrene resin, and a block copolymer having a polyolefin portion and a polystyrene portion. As mentioned above, the hydrogenated product of polystyrene / polybutadiene block copolymer with a specific composition has a remarkable effect as a compatibilizer, and impact strength and elastic modulus while maintaining excellent antistatic properties. There is no suggestion of any significant improvement. Patent Document 2 mentions that antistatic properties are improved by using an alkali metal salt and / or an alkaline earth metal salt in combination with a polyolefin / polyether block copolymer, along with sodium salt and potassium salt. Although lithium salts such as lithium acetate, lithium chloride, and lithium perchlorate are illustrated, there is no suggestion that a lithium salt with a specific structure gives significantly superior antistatic properties compared to other metal salts .

  On the other hand, as a conventional technique, there is a sustained antistatic resin composition comprising a rubber-reinforced styrene resin modified with a carboxyl group or an acid anhydride group, a polyethylene oxide block copolymer, and a metal salt that is solid-solved in a polyethylene oxide component. Known (for example, Patent Document 3). This uses a so-called polymer solid electrolyte formed by a metal salt that dissolves in a polyethylene oxide block copolymer and a polyethylene oxide component as an antistatic agent, and uses a carboxyl group or an acid anhydride group in a rubber-reinforced styrene resin. It is related with the technique which makes it serve as a compatibilizing agent by using what was modified | denatured by (1), keeps a physical property, and avoids delamination. This technology achieves excellent antistatic properties due to ionic conduction of polymer solid electrolytes, but the compatibility between antistatic properties and physical properties is still inadequate, and polyethylene oxide block copolymers are used to maintain high physical properties. It is necessary to suppress the amount of the metal salt that dissolves in the polymer and the polyethylene oxide component, so that the antistatic property is lowered. On the other hand, in order to increase the antistatic property, the solid solution is dissolved in the polyethylene oxide block copolymer and the polyethylene oxide component. When the amount of the metal salt to be increased is increased, there is a problem that the physical properties are lowered. In order to be used for materials for transporting electronic parts, especially large and thin glass parts such as liquid crystal displays and plasma displays, it is necessary to achieve both higher levels of antistatic properties and physical properties. In addition, Patent Document 3 discloses lithium chloride, lithium nitrate, lithium bromide, lithium borohydride, lithium iodide, lithium perchlorate, and the like as sodium salts and potassium salts as metal salts that are solid-dissolved in the polyethylene oxide component. Although a lithium salt is illustrated, there is no suggestion that a lithium salt having a specific structure gives significantly superior antistatic properties compared to other metal salts. Furthermore, in Patent Document 3, in order to produce a resin composition using a metal salt having strong deliquescence, after dissolving a metal salt that dissolves in a polyethylene oxide block copolymer and a polyethylene oxide component in a common solvent. , Refers to a method of removing a solvent to produce a solid solution, but it can be easily and reliably formulated and melted by making a lithium salt with a specific structure dissolved in a chemical liquid with a specific structure. In addition, kneading and granulation can be performed, and the obtained resin composition does not suggest that the antistatic property and the physical properties are balanced in a higher balance.

By the way, the polyethylene oxide block copolymer exhibits antistatic properties by being dispersed in layers. That is, the layered polyethylene oxide block copolymer layer becomes a charge leakage circuit. Therefore, when dispersed in a thin layer, the antistatic property can be expressed with a small amount, and the adverse effects on other physical properties are small. In order to disperse the polyethylene oxide block copolymer in layers, a shear stress must be applied during molding. If no shear stress is applied to the resin composition containing the polyethylene oxide block copolymer, the polyethylene oxide block copolymer is dispersed in a spherical shape in the resin composition. There is almost no connection between the copolymers, no charge leakage circuit is formed, and no antistatic property is exhibited. Even if shear stress is applied at the time of molding, if this stress is small, the polyethylene oxide block copolymer cannot be dispersed in a thin layer, and the antistatic property will be insufficient. Main molding methods include injection molding and extrusion molding. When the sheet is continuously formed, extrusion molding is performed. In particular, a method of giving a shape to a large transport container or the like by forming a sheet and then vacuum forming it is advantageous. Therefore, the resin composition having antistatic properties is often used for extrusion molding, and it is necessary that the extruded composition has sufficient antistatic properties. However, when comparing extrusion molding and injection molding, the former generally has lower shear stress during molding. Therefore, the antistatic property may not be sufficiently exhibited by extrusion molding (Non-Patent Document 1). Non-Patent Document 1 shows the relationship between the amount of polyethylene oxide block copolymer (Pelestat 300) added to polypropylene resin and the surface resistivity. According to this, when the addition amount of the polyethylene oxide block copolymer is relatively small, around 5% by weight, the extrusion-molded product has a surface resistivity of 1 to 2 digits higher than that of the injection molded product. . Increasing the amount of polyethylene oxide block copolymer added to achieve a predetermined surface resistivity value is undesirable because it adversely affects other physical properties such as a decrease in rigidity and a decrease in impact strength. Therefore, it is desired that an extruded product such as a sheet exhibits the same antistatic properties and mechanical properties as the injection molded product.

JP 62-241945 A JP 2001-278985 A Japanese Patent Laid-Open No. 03-103466 Sanyo Chemical Industries "Pelestat 300" technical data

  The present invention combines excellent antistaticity, high balance of impact strength and elastic modulus, and practical heat distortion temperature without losing the original moldability, colorability, and lightness of the styrene resin. It aims at providing the resin composition excellent in the antistatic property in goods.

  As a result of diligent investigations by the present inventor to achieve this problem, the present inventors have determined that a rubber-reinforced styrene resin, a polyethylene oxide block copolymer having a specific composition, a specific polytetrafluoroethylene, and a block copolymer having a specific composition as necessary. A resin composition that is blended, melted, kneaded, and granulated with a specific amount of a hydrogenated product of a coalescence or a specific lithium salt has excellent antistatic properties, fluidity that can be applied to various molding methods, impact strength, and elastic modulus It has been found that it has both a high balance of heat resistance and a practical heat deformation temperature, and is particularly excellent in antistatic properties in an extruded product.

In addition to the rubber-reinforced styrene resin, the specific composition polyethylene oxide block copolymer, the specific polytetrafluoroethylene, the hydrogenated product of the specific composition block copolymer, A resin composition in which lithium salt is blended, melted, kneaded and granulated in a specific amount has an extremely excellent surface resistivity of 10 ⁸ to 10 ⁹ Ω / □ in both injection molded products and extruded products. While exhibiting electrical properties, the present inventors have found that it has fluidity, a high balance of impact strength and elastic modulus, and a practical heat distortion temperature that can be applied to various molding methods, and has reached the present invention.

That is, the present invention is as follows.
(1) Made of rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), and the weight ratio of (A), (B), (C) is A resin composition characterized by satisfying (Equation 1) to (Equation 3).
(Formula 1)
0.80 ≦ (A) / {(A) + (B)} ≦ 0.95
(Formula 2)
0.05 ≦ (B) / {(A) + (B)} ≦ 0.20
(Formula 3)
0.0005 ≦ (C) / {(A) + (B)} ≦ 0.015

(2) Rubber reinforced styrene resin (A) is a rubber reinforced polystyrene resin or a mixture of one or more selected from polystyrene resin, polystyrene / polybutadiene block copolymer rubber and polystyrene / polybutadiene copolymer resin. The resin composition according to (1), wherein

(3) The polyolefin / polyether block copolymer (B) is a copolymer in which a block of a polyolefin having a reactive group at a terminal and a block of a polymer having a polyoxyalkylene as a main structure are repeatedly bonded alternately. The resin composition according to (1) or (2), which is characterized.
(4) Rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), and polystyrene / polybutadiene block copolymer hydrogenated product (D) ( The resin composition according to any one of (1) to (3), wherein the resin composition is added at a weight ratio that satisfies Formula 4).
(Formula 4)
0.20 ≦ (D) / (B) ≦ 1.00

(5) The hydrogenated product of polystyrene / polybutadiene block copolymer (D) is a copolymer in which a block in which 30% or more of double bonds of polystyrene and polybutadiene are saturated by hydrogenation is bonded. The resin composition according to any one of (1) to (4), which is characterized.
(6) A lithium salt (E) represented by the following formula (1) is added to the rubber-reinforced styrene resin (A), the polyolefin / polyether block copolymer (B), and the polytetrafluoroethylene (C) (formula The resin composition according to any one of (1) to (5), which is added at a weight ratio satisfying 5).

（式中、Ｚはトリフロオロメタンスルホニル基を、ｎは１〜３の整数を、Ｙはｎ＝１の場合酸素、ｎ＝２の場合窒素、ｎ＝３の場合炭素を表す。）
（数式５）
０．００１≦（Ｅ）／｛（Ａ）＋（Ｂ）＋（Ｄ）｝≦０．０１０
（７）リチウム塩（Ｅ）を下記式（２）で表される化成品液体に溶解した３０〜７０重量％濃度の溶液の形態で添加したことを特徴とする、（６）に記載の樹脂組成物。

(In the formula, Z represents a trifluoromethanesulfonyl group, n represents an integer of 1 to 3, Y represents oxygen when n = 1, nitrogen when n = 2, and carbon when n = 3.)
(Formula 5)
0.001 ≦ (E) / {(A) + (B) + (D)} ≦ 0.010
(7) The resin according to (6), wherein the lithium salt (E) is added in the form of a solution having a concentration of 30 to 70% by weight dissolved in a chemical product liquid represented by the following formula (2): Composition.

（式中、Ｘは水素、炭素数１〜４のアルキル基、酢酸エステル残基、フタル酸エステル残基或いはアジピン酸エステル残基を、Ｗは水素或いはメチル基を、ｍは１〜９の整数を、Ｖは水素或いは炭素数１〜４のアルキル基を表す。）
（８）リチウム塩（Ｅ）がトリフルオロメタンスルホン酸リチウムであり、該トリフルオロメタンスルホン酸リチウムを分子量２００〜４００のポリエチレングリコールに溶解した３０〜７０重量％濃度の溶液の形態で添加したことを特徴とする、（６）又は（７）に
記載の樹脂組成物。

Wherein X is hydrogen, an alkyl group having 1 to 4 carbon atoms, an acetate ester residue, a phthalate ester residue or an adipate ester residue, W is hydrogen or a methyl group, and m is an integer of 1 to 9. V represents hydrogen or an alkyl group having 1 to 4 carbon atoms.)
(8) The lithium salt (E) is lithium trifluoromethanesulfonate, and the lithium trifluoromethanesulfonate is added in the form of a solution having a concentration of 30 to 70% by weight dissolved in polyethylene glycol having a molecular weight of 200 to 400. The resin composition according to (6) or (7).

  The present invention has excellent antistaticity, impact strength and high balance, and practical heat distortion temperature without losing the original moldability, colorability and lightness of the styrene resin. It is possible to provide an excellent resin composition.

The resin composition having excellent antistatic properties, moldability and mechanical properties of the present invention includes a rubber-reinforced styrene resin, a polyethylene oxide block copolymer having a specific composition, a specific polytetrafluoroethylene, and a specific composition as required. A hydrogenated product of the block copolymer or a specific lithium salt is blended, melted, kneaded and granulated in a specific amount.
The rubber-reinforced styrene resin (A) bears properties such as moldability, physical property balance between impact strength and elastic modulus, and heat distortion temperature in the resin composition of the present invention. Polymerized resin etc. can be illustrated.

  A rubber-reinforced polystyrene resin (hereinafter referred to as HIPS) is a molding material in which a rubber-like elastic material is dispersed in a continuous phase composed of a polymer of styrene alone, and a generally available material is appropriately selected and used. Can do. Generally available HIPS are adjusted in degree of polymerization of styrene, type and amount of rubber-like elastic body, dispersed particle size, amount of plasticizer and lubricant, and have different fluidity, impact strength, elastic modulus and heat distortion temperature. Things are offered. When HIPS having preferable fluidity, impact strength, elastic modulus and heat distortion temperature is not available, polystyrene resin (hereinafter referred to as GPPS), polystyrene / polybutadiene block copolymer elastomer (hereinafter referred to as SBS elastomer), polystyrene / polybutadiene. A block copolymer resin (hereinafter referred to as SBS resin) can be blended with HIPS, and the fluidity, impact strength, elastic modulus, and heat distortion temperature can be preferably adjusted. The rubber-reinforced methacrylstyrene copolymer resin (hereinafter referred to as transparent HIPS) is a rubber having a composition in which the refractive index coincides with that of a continuous phase composed of a copolymer of methyl methacrylate, alkyl (meth) acrylate and styrene. It is a molding material formed by dispersing a shaped elastic body with a particle diameter smaller than the wavelength of visible light, and a generally available material can be appropriately selected and used. Transparent HIPS that is generally available is the amount of methyl methacrylate, the type and amount of alkyl (meth) acrylate, the degree of polymerization of these and styrene, the type and amount of rubber-like elastic material, the dispersed particle size, the amount of plasticizer and lubricant. Are adjusted to provide different transparency, fluidity, impact strength, elastic modulus, and heat distortion temperature. When transparent HIPS having preferable fluidity, impact strength, elastic modulus and heat distortion temperature is not available, methacryl styrene copolymer resin (hereinafter referred to as MS resin), SBS elastomer or SBS resin is blended with transparent HIPS, The fluidity, impact strength, elastic modulus, and heat distortion temperature can be preferably adjusted.

The fluidity of the rubber-reinforced styrene resin (A) is preferably in the range of 1 to 4 g / 10 min in melt flow rate measured according to ISO1133. When the fluidity of the rubber-reinforced styrene resin (A) is less than the above range, the moldability of the resin composition of the present invention, particularly the mold filling property in the injection molding, is not preferable. On the other hand, if the fluidity of the rubber-reinforced styrene-based resin (A) exceeds the above range, the moldability of the resin composition of the present invention, particularly the thickness uniformity in extrusion molding, vacuum molding, and blow molding, is unfavorable. . The impact strength of the rubber-reinforced styrenic resin (A) is preferably a Charpy impact strength measured according to ISO 179 of 5 KJ / m ² or more.

If the impact strength of the rubber-reinforced styrene resin (A) is less than the above, the following polyolefin / polyether block copolymer (B) has the property of lowering the impact strength of the resin composition. The composition may cause problems due to the impact strength in practical use. The elastic modulus of the rubber-reinforced styrene resin (A) is 2 in flexural modulus measured according to ISO178.
It is preferably 200 MPa or more. The following polyolefin / polyether block copolymer (B) and polystyrene / polybutadiene block copolymer hydrogenated product (D) have the property of lowering the elastic modulus. Therefore, if the elastic modulus of the rubber-reinforced styrene resin (A) is less than the above, the resin composition of the present invention may cause problems such as insufficient rigidity. The thermal deformation temperature of the rubber-reinforced styrene resin (A) is preferably a Vicat softening temperature measured according to ISO 306 of 85 ° C. or higher. Since the following hydrogenated product (D) of polyolefin / polyether block copolymer (B) and polystyrene / polybutadiene block copolymer has the property of lowering the heat distortion temperature of the resin composition, rubber reinforced styrene resin (A If the thermal deformation temperature is not more than the above, the practical temperature of the resin composition of the present invention, for example, cargo transportation is limited, which is not preferable.

  The polyolefin / polyether block copolymer (B) bears excellent antistatic properties in the resin composition of the present invention. The polyolefin / polyether block copolymer (B) absorbs static electricity and attenuates the charged voltage due to environmental moisture absorption, water ionic dissociation, and proton ionic conduction in the polyether block. The resin composition exhibits continuous antistatic properties.

  Polyolefin / polyether block copolymer (B) is a copolymer in which a polyolefin block having a reactive group at the end and a polymer block mainly composed of polyoxyalkylene are alternately bonded, and is generally available. What can be used can be appropriately selected and used. Generally available polyolefin / polyether block copolymers include the structural unit structure and polymerization molecular weight of polyolefin, the structural unit structure and polymerization molecular weight of polyether, the terminal reactive group of the polyolefin block and the terminal reactive group of the polyether block. Different ones are provided, such as the structure of the bonds formed and the number of repeats of alternating bonds of polyolefin blocks and polyether blocks. There are no particular limitations on the elements that characterize these polyolefin / polyether block copolymers. When a polyolefin / polyether block copolymer having a melting point (the temperature at the peak top of the DSC chart, the same applies hereinafter) of 150 ° C. or higher is selected, the resin composition of the present invention has superior antistatic properties and higher The physical property balance is preferable.

A plurality of polyolefin / polyether block copolymers may be blended to form a polyolefin / polyether block copolymer (B). In that case, it preferably contains at least one polyolefin / polyether block copolymer having a melting point of 150 ° C. or higher.
The blending amount of the polyolefin / polyether block copolymer (B) is represented by the following (Equation 1) and (Equation 2).
(Formula 1)
0.80 ≦ (A) / {(A) + (B)} ≦ 0.95
(Formula 2)
0.05 ≦ (B) / {(A) + (B)} ≦ 0.20

The total of the rubber-reinforced styrene resin (A) and the polyolefin / polyether block copolymer (B) is 100% by weight, and the rubber-reinforced styrene resin (A) is 80 to 95% by weight, preferably 85 to 95% by weight. More preferably, it is 88 to 93% by weight, and the polyolefin / polyether block copolymer (B) is 5 to 20% by weight, preferably 5 to 15% by weight, and more preferably 7 to 12% by weight. When the rubber-reinforced styrene-based resin (A) is less than 80% by weight, that is, when the polyolefin / polyether block copolymer (B) exceeds 20% by weight, the elongation at break, impact strength, and elastic modulus of the resin composition are lowered. In addition, the heat distortion temperature is lowered, which is not preferable. On the other hand, if the rubber-reinforced styrene resin (A) exceeds 95% by weight, that is, if the polyolefin / polyether block copolymer (B) is less than 5% by weight, the antistatic property of the resin composition is poor, which is not preferable.

The polytetrafluoroethylene (C) used in the present invention is considered to have an effect of efficiently dispersing the polyolefin-polyether block copolymer (B) in the resin even under a low shear stress. Accordingly, the antistatic property comparable to that of the injection-molded product can be exhibited even in an extrusion-molded sheet having a lower shear stress during molding than the injection-molded product.
The polytetrafluoroethylene (C) preferably has a fibril forming ability. That is, it has the function of dispersing in the resin, taking a fibrous network structure, and improving the melt tension of the molten resin. Polytetrafluoroethylene having fibril-forming ability is often used for the purpose of preventing dripping of molten resin during combustion and improving die swell, and is commercially available. For example, Daikin Industries, Ltd. Polyflon PTFE F-104 (trade name), F-201 (trade name), Polyflon MPA FA-500 (trade name), Asahi Glass Co., Ltd. full-on CD-076 (trade name) And Teflon (R) 6J (trade name) of Mitsui-DuPont Fluorochemical Co., Ltd.

  The polytetrafluoroethylene (C) used in the present invention does not need to be polytetrafluoroethylene alone as long as it has a function of fibrillating and improving the melt tension of the molten resin, and may be modified polytetrafluoroethylene. . For example, Mitsubishi Rayon Co., Ltd. Metablen A-3000 (trade name) obtained by modifying polytetrafluoroethylene with an acrylic resin can be used.

The compounding quantity of polytetrafluoroethylene (C) is shown by the following (Formula 3).
(Formula 3)
0.0005 ≦ (C) / {(A) + (B)} ≦ 0.015
The total of the rubber-reinforced styrene resin (A) and the polyolefin / polyether block copolymer (B) is 100 parts by weight, and the polytetrafluoroethylene (C) is 0.05 to 1.5 parts by weight, preferably 0.8. 1 to 1.0 part by weight, more preferably 0.2 to 0.8 part by weight. If the amount is less than 0.05 parts by weight, almost no improvement in antistatic property is observed in the sheet. On the other hand, if it exceeds 1.5 parts by weight, the antistatic property improving effect in the extruded product is not preferable because the breaking elongation and impact strength of the resin composition are remarkably lowered despite the peak.

  The hydrogenated product (D) of the polystyrene / polybutadiene block copolymer plays a role of achieving both excellent antistatic properties and a high balance of physical properties in the resin composition of the present invention. The hydrogenated product (D) of polystyrene / polybutadiene block copolymer is a stable integration of the rubber-reinforced styrene resin (A) and the polyolefin / polyether block copolymer (B) under a preferred phase separation form. Therefore, the resin composition of the present invention exhibits a balance of physical properties based on the rubber-reinforced styrenic resin (A) while demonstrating the antistatic property based on the polyolefin / polyether block copolymer (B). Maintain to the maximum.

The hydrogenated product (D) of the polystyrene / polybutadiene block copolymer is a copolymer in which a polystyrene block and a block in which a double bond of polybutadiene is saturated by hydrogenation are bonded. It can be selected and used. It is also called a styrene / ethylene / butylene styrene block copolymer (SEBS elastomer) or a styrene / butylene / butylene styrene block copolymer (SBBS elastomer). Generally available hydrogenated polystyrene / polybutadiene block copolymers include polystyrene, polybutadiene polymerization degree, polybutadiene 1,4-structure to vinyl structure ratio, A-B type, A-B-A. Different types of elements such as block type, A-B-A-B type, block styrene content, butadiene content, and degree of saturation of double bond by hydrogenation are provided. . Each element characterizing the hydrogenated product of these polystyrene / polybutadiene block copolymers is not limited. However, in order to achieve both excellent antistatic properties and a good balance of physical properties in the resin composition of the present invention, two components by hydrogenation may be used. The degree of saturation of the heavy bond is preferably 30% or more. More preferred is a hydrogenated product of a polystyrene-polybutadiene block copolymer having a styrene content of the whole copolymer of 50% by weight or more and a degree of saturation of double bonds by hydrogenation of 30% or more.

A hydrogenated product (D) of a polystyrene / polybutadiene block copolymer may be prepared by blending a plurality of polystyrene / polybutadiene block copolymer hydrogenated products. In that case, at least one kind of hydrogenated polystyrene-polybutadiene block copolymer in which the styrene content of the entire copolymer is 50% by weight or more and the degree of saturation of double bonds by hydrogenation is 30% or more. It is preferable that it contains.
The blending amount of the hydrogenated product (D) of the polystyrene / polybutadiene block copolymer is represented by the following (Equation 4).
(Formula 4)
0.20 ≦ (D) / (B) ≦ 1.00

Based on 100 parts by weight of the polyolefin / polyether block copolymer (B), the blending amount of the hydrogenated product (D) of the polystyrene / polybutadiene block copolymer is 20 to 100 parts by weight, preferably 30 to 100 parts by weight. is there. When the hydrogenated product (D) of the polystyrene-polybutadiene block copolymer is less than 20 parts by weight, the elongation at break and impact strength of the resin composition are low, which is not preferable. On the other hand, if the hydrogenated product (D) of the polystyrene / polybutadiene block copolymer exceeds 100 parts by weight, the fluidity of the resin composition falls outside an appropriate range, and the moldability is deteriorated. Is not preferable.
The lithium salt (E) is represented by the following formula (1).

（式中、Ｚはトリフロオロメタンスルホニル基を、ｎは１〜３の整数を、Ｙはｎ＝１の場合酸素、ｎ＝２の場合窒素、ｎ＝３の場合炭素を表す。）

(In the formula, Z represents a trifluoromethanesulfonyl group, n represents an integer of 1 to 3, Y represents oxygen when n = 1, nitrogen when n = 2, and carbon when n = 3.)

  The lithium salt (E) represented by the above formula (1) is one kind of alkali metal salt, and the alkali metal has the smallest ion radius and the largest degree of freedom of ion movement, and the electron withdrawing force. Since it has a strong trifluoromethane group, it is characterized by comprising an organic anion having a high degree of ionic dissociation. The lithium salt (E) is stably and highly ion-dissociated in the polyether block of the polyolefin-polyether block copolymer (B), dissipates static electricity instantaneously by ionic conduction, and attenuates the charged voltage. The resin composition of the present invention does not depend on moisture in the environment, and exhibits outstanding antistatic properties stably and continuously. Further, in many alkali metal salts that adversely affect the impact strength of the resin composition, the lithium salt (E) maintains a high impact strength of the resin composition of the present invention.

  The lithium salt (E) represented by the above formula (1) can be appropriately selected from those generally available. Preferably, lithium is trifluoromethane sulfonate with n = 1 and Y is oxygen, and bis (trifluoromethanesulfonyl) imide lithium with n = 2 and Y is nitrogen. n = 3 and Y is carbon (tristrifluoromethanesulfonyl) methanelithium is an anion having a high degree of ionic dissociation but a large molecular weight, so it is slightly inferior to the former two when compared with the same addition amount. Lithium trifluoromethanesulfonate has the smallest anion molecular weight, and bis (trifluoromethanesulfonyl) imide lithium has the highest degree of ionic dissociation of the anion.

A plurality of lithium salts can be blended to form a lithium salt (E). In that case, it preferably contains at least one selected from lithium trifluoromethanesulfonate and lithium bis (trifluoromethanesulfonyl) imide. The lithium salt (E) can be blended, melted, kneaded and granulated as it is, but in order to avoid uneven distribution due to a small blending amount, the above-mentioned polyolefin / polyether block copolymer ( In order to selectively disperse in B) and enhance ion conduction, blending, melting, kneading, and granulation in the form of a 30 to 70% by weight solution dissolved in the chemical product liquid represented by the following formula (2) It is also possible to do.

（式中、Ｘは水素、炭素数１〜４のアルキル基、酢酸エステル残基、フタル酸エステル残基或いはアジピン酸エステル残基を、Ｗは水素或いはメチル基を、ｍは１〜９の整数を、Ｖは水素或いは炭素数１〜４のアルキル基を表す。）

Wherein X is hydrogen, an alkyl group having 1 to 4 carbon atoms, an acetate ester residue, a phthalate ester residue or an adipate ester residue, W is hydrogen or a methyl group, and m is an integer of 1 to 9. V represents hydrogen or an alkyl group having 1 to 4 carbon atoms.)

  In order to dissolve the lithium salt (E) having a high degree of ion dissociation at an appropriate concentration, and to selectively disperse the lithium salt (E) in the polyolefin-polyether block copolymer (B), The product liquid preferably has a specific structure represented by the above formula (2). These chemical product liquids include ethylene glycol (m = 1), diethylene glycol (m = 2), triethylene glycol (m = 3), polyethylene glycol (m = 4 to 9) in which X, W and V are hydrogen, Propylene glycol in which X and Y are hydrogen and W is a methyl group and a polymer thereof (m = 1 to 9), ethyl glycol in which X and W are hydrogen and V is an ethyl group (m = 1), ethyl diglycol ( m = 2), ethyl triglycol (m = 3), X is an acetate residue, W and V are methyl groups and m = 1 methoxypropyl acetate, X is a phthalate residue, W is hydrogen, V is Bis (ethyldiglycol) phthalate with ethyl group m = 2, X is adipic acid ester residue, W is hydrogen, V is butyl group and m = 2 bis (butyldiglycol) adipate Shown, it may be used as the commonly available appropriately selecting.

Preferably, a solution comprising lithium trifluoromethanesulfonate and polyethylene glycol having a molecular weight of 200 to 400, which forms a stable lithium salt (E) solution in a wide concentration range, bis (trifluoromethanesulfonyl) imide lithium and bis (butyl) Diglycol) A solution composed of adipate.
The concentration when the above lithium salt (E) is dissolved in the above chemical product liquid to form a solution is 30 to 70% by weight. When the concentration is less than 30% by weight, it is necessary to blend a larger amount of solution in order to contain a predetermined amount of lithium salt (E) in the resin composition. That is, the chemical product liquid is added in excess, which is not preferable because the moldability of the resin composition is lowered and the practical temperature is limited. On the other hand, if it exceeds 70% by weight, a very small amount of solution is added to contain a predetermined amount of lithium salt (E) in the resin composition, which is not preferable because the problem of uneven distribution cannot be solved.

The amount of the lithium salt (E) is as follows in relation to the rubber-reinforced styrene resin (A), the polyolefin / polyether block copolymer (B), and the hydrogenated product (D) of the polystyrene / polybutadiene block copolymer. It is shown by (Formula 5).
(Formula 5)
0.001 ≦ (E) / {(A) + (B) + (D)} ≦ 0.010
The sum of the rubber-reinforced styrene resin (A), the polyolefin / polyether block copolymer (B) and the hydrogenated product (D) of the polystyrene / polybutadiene block copolymer is 100.
As parts by weight, the lithium salt (E) is 0.1 to 1.0 parts by weight, preferably 0.1 to 0.8 parts by weight. When the lithium salt (E) is less than 0.1 parts by weight, the antistatic property of the resin composition is not improved, which is not preferable. On the other hand, even if the lithium salt (E) exceeds 1.0 part by weight, the improvement of the antistatic property is no longer satisfactory, and the lithium salt may be deposited on the surface of the resin composition, which is not preferable.

  Rubber reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), polystyrene / polybutadiene block copolymer hydrogenated product (D) and lithium salt (E) The method of blending, melting, kneading and granulating is not particularly limited, and a method commonly used in the production of resin compositions can be used. For example, by melting and kneading the above ingredients blended with a drum tumbler, Henschel mixer, etc. using a Banbury mixer, single screw extruder, twin screw extruder, kneader ruder, etc., and granulating with a rotary cutter, fan cutter, etc. A resin composition can be obtained. The melting and kneading process temperature is preferably 20 ° C. or more higher than the melting point of the polyolefin / polyether block copolymer (B) having crystallinity.

  From rubber reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), polystyrene / polybutadiene block copolymer hydrogenated product (D) and lithium salt (E) When the resin composition to be manufactured is manufactured, the polyolefin / polyether block copolymer (B) and the lithium salt (E) are first blended instead of the method of batch blending, melting, kneading and granulating as described above. , Melting, kneading, and granulating to produce an intermediate raw material, and then blending, melting, and kneading the intermediate raw material, a rubber-reinforced styrene resin (A), and a hydrogenated product of polystyrene / polybutadiene block copolymer (D) A method of granulating can also be used.

  The method of blending, melting, kneading, and granulating when lithium salt (E) is added in the form of a solution dissolved in a chemical liquid is not particularly limited, and is commonly used in the production of resin compositions using liquid raw materials. Can apply the method. For example, rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), and hydrogenated product (D) of polystyrene / polybutadiene block copolymer, which are solid raw materials, are Blended with a drum tumbler, Henschel mixer, etc., and supplied to a feed hopper such as a twin screw extruder, kneader ruder, etc. A resin composition can be obtained by pouring into a cylinder such as a rudder, melting, kneading, and granulating with a rotary cutter, a fan cutter or the like.

The lithium salt (E) can be selectively dispersed in the polyolefin / polyether block copolymer (B) by forming a solution in which the lithium salt (E) is dissolved in the chemical liquid. Therefore, it is not necessary to melt and knead the polyolefin / polyether block copolymer (B) and the lithium salt (E) in advance as described above to produce an intermediate raw material, and the resin composition of the present invention can be reasonably provided. Can be manufactured.
Further, the resin composition of the present invention is a hydrogenated product of rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), polystyrene / polybutadiene block copolymer. Additions commonly used in HIPS and transparent HIPS such as antioxidants, lubricants, colorants, UV absorbers, and light stabilizers when (D) and lithium salt (E) are blended, melted, kneaded and granulated An agent can be added.

The resin composition of the present invention is molded into a resin product by a method generally used in HIPS and transparent HIPS such as injection molding, sheet extrusion molding, vacuum molding, profile extrusion molding, and blow molding. The resin product obtained by molding the resin composition of the present invention has excellent antistatic properties, excellent surface hardness, and excellent strength. It is suitable for electronic parts carrying materials that are repeatedly washed and used repeatedly.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further, this invention is not limited to a following example, unless the summary is exceeded.
<Rubber reinforced styrene resin (A)>
Rubber Japan Reinforced Styrene Resin (A) with PS Japan Corporation's HIPS “475D” (trade name) and 100 parts by weight of GPPS “685” (trade name), 115 parts by weight. It was. The melt flow rate of this rubber-reinforced styrene resin (A) measured according to ISO 1133 is 2.5 g / 10 min, the Charpy impact strength measured according to ISO 179 is 8 KJ / m ² , the flexural modulus measured according to ISO 178 is 2700 MPa, and according to ISO 306. The measured Vicat softening temperature was 99 ° C.

<Polyolefin / polyether block copolymer (B)>
“Pelestat 230” (trade name) manufactured by Sanyo Chemical Industries, Ltd. was selected as the polyolefin / polyether block copolymer (B). A polyolefin / polyether block copolymer having a melting point of 135 ° C. measured as the peak top temperature of the DSC chart.
<Polytetrafluoroethylene (C)>
“Freon CD-076” (trade name) manufactured by Asahi Glass Co., Ltd. was selected as the polytetrafluoroethylene (C).

<Hydrogenated product of polystyrene / polybutadiene block copolymer (D)>
As a hydrogenated product (D) of the polystyrene / polybutadiene block copolymer, “Tuftec H1043” (trade name) manufactured by Asahi Kasei Chemicals Corporation was selected.
<Lithium salt (E)>
“Sanconol PEG200-50T” (trade name) manufactured by Sanko Chemical Co., Ltd. was selected as the lithium salt (E). This is a 50% by weight solution of lithium trifluoromethanesulfonate dissolved in polyethylene glycol having a molecular weight of 200.

<Manufacture of resin composition>
Rubber reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), hydrogenated product of polystyrene / polybutadiene block copolymer (D), lithium salt (E) It measured as shown in the upper stage of (Table 1)-(Table 6).
The measured raw materials were blended with a drum tumbler, melted and kneaded at a cylinder setting temperature of 220 ° C. and a screw rotation speed of 200 rpm with a same-direction twin screw extruder (ZSK25 manufactured by WERNER & PFLEIDERER), and extracted as a molten strand. The molten strand was cooled with water and the strand was cut with a rotary cutter to obtain a pellet-shaped resin composition.

<Extruded sheet molding>
Extrusion sheet molding was performed using the resin composition obtained in the above <Manufacture of resin composition>. The resin composition was put into a single screw extruder and melted at a cylinder temperature of 220 ° C., and a molten sheet was extruded from a T die.
The discharge amount is 10 kg / hr, and the discharge port size of the T die is 30 cm wide and 0.5 mm thick. The molten sheet discharged from the T-die was cooled with a roll at 65 ° C., and the take-up speed was adjusted so that the sheet thickness was 0.4 mm.

<Measurement of physical properties-1> Measurement of resistivity Injection molded product; 100 mm × 100 of the resin composition obtained in the above <Manufacture of resin composition>
A flat plate test piece of mm × 2.5 mm was injection-molded, pretreated for 4 days / 23 ° C./50% RH, and then surface resistivity was measured according to JIS K6911.
Extruded sheet: A sheet test piece of 100 mm × 100 mm was cut out from the sheet molded as described above, and after pretreatment for 4 days / 23 ° C./50% RH, the surface resistivity was measured according to JIS K6911. The surface resistivity was measured at 500 V using an ultra-super insulation meter (TOAULTRA MEGOHMMETERSM-8210 manufactured by Toa Denpa Kogyo Co., Ltd.).
The above measurement results are shown in the lower part of Tables 1-6. (Note, E + 08-15 in Table 1-6 means ^{10 8-15.)}

<Measurement of Physical Properties-2> Measurement of Melt Flow Rate and Mechanical Properties The melt flow rate of the resin composition obtained in <Production of Resin Composition> was measured according to ISO 1133. Also, the resin composition produced above is injection molded into an ISO type A test piece, tensile strength and tensile breaking strain according to ISO 527-1, Charpy impact strength according to ISO 179, flexural modulus according to ISO 178, and according to ISO 306. Vicat softening temperature was measured.
The above measurement results are shown in the lower part of Tables 1 to 6.

Description of rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), and polytetrafluoroethylene (C) blended system (Tables 1-2):
When polytetrafluoroethylene (C) is not added (Comparative Examples A to C), the ratio of the surface resistivity between the extruded sheet and the injection molded product (extruded sheet surface resistivity / injection molded product surface resistivity) exceeds 3. Yes. By adding polytetrafluoroethylene (C) (Examples 1 to 5), the reduced range of the surface resistivity of the injection molded product is small, but the surface resistivity of the extruded sheet product is greatly reduced. The ratio of the surface resistivity of the injection molded product is less than 2.5.

When the amount of polytetrafluoroethylene (C) added falls below the range of the present invention (Comparative Example 1)
) Shows almost no reduction in the surface resistivity ratio. On the other hand, when the addition amount of polytetrafluoroethylene (C) exceeds the range of the present invention (Comparative Example 2), the reduction range of the ratio of the surface resistivity is not constant, and unevenness is generated on the sheet surface.
When the blending amount of the polyolefin / polyether block copolymer (B) exceeds the range of the present invention (Comparative Example 3), the surface resistivity is low and excellent, but the flexural modulus is greatly below 2000 MPa and the rigidity is low. , Vicat softening temperature also decreases. When the blending amount of the polyolefin / polyether block copolymer (B) falls below the range of the present invention (Comparative Example 4), the surface resistivity is high, and even if polytetrafluoroethylene (C) is added, antistatic properties are obtained. There is no improvement.

Rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), polystyrene / polybutadiene copolymer hydrogenated compound (D) blended system (Tables 3 to 4) Description:
When polytetrafluoroethylene (C) is not added (Comparative Examples D to F), the ratio of the surface resistivity between the extruded sheet and the injection molded product exceeds 3, whereas polytetrafluoroethylene (C) is added. By doing this (Examples 6 to 10), the surface resistivity of the extruded sheet product is reduced, and the ratio of surface resistivity is less than 2.5.

  When the amount of polytetrafluoroethylene (C) added falls below the range of the present invention (Comparative Example 5), almost no reduction in the surface resistivity ratio is observed. On the other hand, when the addition amount of polytetrafluoroethylene (C) exceeds the range of the present invention (Comparative Example 6), the reduction width of the ratio of the surface resistivity is peaked, unevenness is generated on the sheet surface, Tensile fracture strain and Charpy impact strength are also lowered, which is not preferable.

When the blending amount of the polyolefin / polyether block copolymer (B) exceeds the range of the present invention (Comparative Example 7), the surface resistivity is low and excellent, but the flexural modulus is significantly below 2000 MPa, and the rigidity is low. Low. When the blending amount of the polyolefin / polyether block copolymer (B) falls below the range of the present invention (Comparative Example 8), the surface resistivity is high, and even if polytetrafluoroethylene (C) is added, antistatic properties are obtained. Is not expressed.
When the blending amount of the polystyrene / polybutadiene copolymer hydrogenated product (D) exceeds the range of the present invention (Reference Example 1), the flexural modulus is low and the Vicat softening temperature is also lowered. When the blending amount of the polystyrene / polybutadiene copolymer hydrogenated product (D) is below the range of the present invention (Reference Example 2), the blending effect is not obtained while the tensile breaking strain and the Charpy impact strength remain low.

System containing rubber reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), polystyrene / polybutadiene copolymer hydrogenated product (D), lithium salt (E) Explanation of (Tables 5-6):
When polytetrafluoroethylene (C) is not added (Comparative Examples G to H), the ratio of the surface resistivity of the extruded sheet to the injection molded product (extruded sheet surface resistivity / injection molded product surface resistivity) is 5 to 10 Although it is very large, by adding polytetrafluoroethylene (C) (Examples 11 to 14), the surface resistivity ratio is less than 2, and the antistatic property of the sheet is greatly improved. .

When the amount of polytetrafluoroethylene (C) added falls below the range of the present invention (Comparative Example 9), almost no reduction in the surface resistivity ratio is observed. On the other hand, when the amount of polytetrafluoroethylene (C) added exceeds the range of the present invention (Comparative Example 10), the range of reduction in the ratio of surface resistivity is peak, unevenness is generated on the sheet surface, and tensile strength is increased. Breaking strain and Charpy impact strength are also lowered, which is not preferable.
When the blending amount of the lithium salt (E) is below the range of the present invention (Reference Example 3), the reduction range of the surface resistivity is slight and the antistatic property is insufficient. On the other hand, when the blending amount of the lithium salt (E) exceeds the range of the present invention (Reference Example 4), the reduction range of the surface resistivity is peak, and the flexural modulus and Vicat softening temperature also tend to decrease, preferably Absent.

  The resin composition of the present invention is preferably used for applications that play a role of protecting the contents electrically and physically, such as electronic parts carrying materials.

Claims (8)

It consists of rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), and polytetrafluoroethylene (C). The weight ratio of (A), (B), and (C) is as follows (Formula 1 ) To (Formula 3).
(Formula 1)
0.80 ≦ (A) / {(A) + (B)} ≦ 0.95
(Formula 2)
0.05 ≦ (B) / {(A) + (B)} ≦ 0.20
(Formula 3)
0.0005 ≦ (C) / {(A) + (B)} ≦ 0.015   The rubber-reinforced styrene resin (A) is a rubber-reinforced polystyrene resin, or a mixture of at least one selected from polystyrene resin, polystyrene / polybutadiene block copolymer rubber and polystyrene / polybutadiene copolymer resin. The resin composition according to claim 1, wherein:   The polyolefin / polyether block copolymer (B) is a copolymer in which a polyolefin block having a reactive group at a terminal and a polymer block having a main structure of polyoxyalkylene are alternately and repeatedly bonded. The resin composition according to claim 1 or 2. The rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), polytetrafluoroethylene (C), polystyrene / polybutadiene block copolymer hydrogenated product (D) are shown below (Formula 4). The resin composition according to any one of claims 1 to 3, wherein the resin composition is added at a weight ratio that satisfies the conditions.
(Formula 4)
0.20 ≦ (D) / (B) ≦ 1.00   The hydrogenated product (D) of the polystyrene / polybutadiene block copolymer is a copolymer in which a block in which 30% or more of double bonds of polystyrene and polybutadiene are saturated by hydrogenation is bonded. The resin composition according to any one of claims 1 to 4. A lithium salt (E) represented by the following formula (1) is added to the rubber-reinforced styrene resin (A), polyolefin / polyether block copolymer (B), and polytetrafluoroethylene (C). The resin composition according to any one of claims 1 to 5, wherein the resin composition is added at a filling weight ratio.

(In the formula, Z represents a trifluoromethanesulfonyl group, n represents an integer of 1 to 3, Y represents oxygen when n = 1, nitrogen when n = 2, and carbon when n = 3.)
(Formula 5)
0.001 ≦ (E) / {(A) + (B) + (D)} ≦ 0.010 The resin composition according to claim 6, wherein the lithium salt (E) is added in the form of a solution having a concentration of 30 to 70% by weight dissolved in a chemical liquid represented by the following formula (2).

Wherein X is hydrogen, an alkyl group having 1 to 4 carbon atoms, an acetate ester residue, a phthalate ester residue or an adipate ester residue, W is hydrogen or a methyl group, and m is an integer of 1 to 9. V represents hydrogen or an alkyl group having 1 to 4 carbon atoms.)   The lithium salt (E) is lithium trifluoromethanesulfonate, and the lithium trifluoromethanesulfonate is added in the form of a solution having a concentration of 30 to 70% by weight dissolved in polyethylene glycol having a molecular weight of 200 to 400, The resin composition according to claim 6 or 7.