Piping components

Abstract

To provide a cylindrical or tubular piping member that has excellent impact resistance and high strength. [Solution] The piping member 1 of the present invention comprises a portion 3 whose inner surface in contact with liquid is made of a resin composition, and this resin composition contains a polyphenylene ether resin and a styrene elastomer, wherein the styrene elastomer is at least one selected from styrene-ethylene-propylene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer and styrene-butadiene-styrene copolymer, and the amount of styrene units contained in the styrene elastomer is 25 to 65% by mass relative to the styrene elastomer.

Description

[Technical Field]

[0001] The present invention relates to a piping member having a portion of its inner surface, which comes into contact with a liquid, made of a resin composition containing a polyphenylene ether resin. [Background technology]

[0002] Conventionally, in the manufacturing of semiconductor-related products, for example, in wet processes such as cleaning, ultrapure water purified to an extremely high degree of purity, or ultra-high purity cleaning solutions purified to an extremely high degree of purity according to the required composition, have been used.

[0003] As a resin used for piping in semiconductor cleaning solutions, fluororesins that are chemically inert and possess gas barrier properties are used. For example, Patent Document 1 discloses a double-walled fluororesin tube, which is made of two layers of fluororesin, as piping used in semiconductor manufacturing equipment. The inner layer tube is made of a fluororesin with excellent corrosion resistance and chemical resistance (for example, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), or tetrafluoroethylene-ethylene copolymer (ETFE)), and the outer layer tube is made of a fluororesin that can suppress gas permeation (for example, polyvinylidene fluoride (PVDF)). Patent Document 2 also discloses a multilayer tube for ultrapure water piping, which is made of fluororesin and comprises a first resin layer that comes into contact with ultrapure water, and a second resin layer made of a gas-impermeable resin and provided on the outer circumferential surface of the first resin layer. Furthermore, it is disclosed that a third resin layer is provided on the outer circumferential surface of the second resin layer to protect the second resin layer, and that polyethylene is used as the third resin layer.

[0004] Among the resins used as materials for semiconductor cleaning fluid piping, PVDF is used in all applications in the semiconductor field, including piping within semiconductor cleaning fluid manufacturing equipment and piping for transporting semiconductor cleaning fluid from the manufacturing equipment to the point of use, and has become the technical standard for semiconductor cleaning fluid piping. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2006-112507 [Patent Document 2] Japanese Patent Publication No. 2010-234576 [Overview of the project] [Problems that the invention aims to solve]

[0006] The objective of the present invention is to provide a piping member that has excellent impact resistance and high strength. [Means for solving the problem]

[0007] The present invention is described below. 1. A piping member having a portion whose inner surface in contact with a liquid is made of a resin composition, The above resin composition contains a polyphenylene ether resin and a styrene elastomer. The above-mentioned styrene-based elastomer is at least one selected from styrene-ethylene-propylene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, and styrene-butadiene-styrene copolymer. A piping component characterized in that the amount of styrene units contained in the above-mentioned styrene-based elastomer is 25 to 65% by mass relative to the above-mentioned styrene-based elastomer. 2. The piping member according to item 1, wherein the content of the styrene-based elastomer is 3 to 25% by mass relative to the resin composition. 3. The piping member according to item 1 above, wherein the melt flow rate (260 ° C, 10 kgf) of the resin composition is 6.0 to 25 g / 10 min. 4. The piping member according to item 1 above, wherein the inner surface has a portion with a surface roughness Rz of 0.5 μm or less. 5. The piping member according to item 1 above, wherein the piping member is a pipe, tube, joint, flange or valve.

Advantages of the Invention

[0008] The piping member of the present invention includes a portion made of a resin composition containing a styrene-based elastomer having a styrene unit content of 25 to 65% by mass, so it has excellent impact resistance and high strength. The piping member of the present invention has high tensile elastic modulus and tensile fracture strain at both normal temperature and 80 ° C, and thus has resistance to external forces. For example, it is useful in industries that utilize liquids at 120 ° C or lower through piping.

Brief Description of the Drawings

[0009] [Figure 1] It is a schematic diagram showing an example of the cross-sectional structure of the piping member of the present invention. [Figure 2] It is a schematic diagram showing another example of the cross-sectional structure of the piping member of the present invention.

Embodiments for Carrying Out the Invention

[0010] The piping member of the present invention is, for example, a pipe, tube, joint, flange or valve, and is a cylindrical or tubular article including a portion (hereinafter referred to as the "first pipe portion") made of a resin composition containing a polyphenylene ether-based resin and a styrene-based elastomer of a specific type and having a specific styrene unit content, with which the liquid comes into contact.

[0011] The piping member of the present invention may consist only of the first pipe portion, or may include the first pipe portion and an exterior portion, a reinforcing portion, etc. formed on at least a part of its outer surface.

[0012] Figures 1 and 2 are schematic diagrams illustrating the cross-sectional structure of the piping member of the present invention. The piping member 1 in Figure 1 is a multi-layered piping member comprising a first pipe section 3 and an outer covering section 5 formed on at least a part of its outer surface. The piping member 1 in Figure 2 is a piping member consisting only of the first pipe section 3. Thus, the piping member of the present invention has a structure in which the liquid flowing through it comes into contact with the inner surface of the first pipe section 3, that is, the surface where the resin composition is exposed.

[0013] The resin composition according to the present invention contains a polyphenylene ether resin and a styrene elastomer having a styrene unit content of 25 to 65% by mass, and may further contain other components (described later).

[0014] The polyphenylene ether resin according to the present invention is a resin component that can be used to manufacture resin molded articles, and preferably comprises a polyphenylene ether resin and another resin. When the polyphenylene ether resin comprises a polyphenylene ether resin and another resin, it may be a simple mixture in which the two can be easily separated, or it may be a composite in which the two are intertwined and do not easily separate. The content of the polyphenylene ether resin in the resin composition is preferably 60% or more, and more preferably 70% or more.

[0015] Polyphenylene ether resin is a resin containing at least one structural unit represented by the following general formula (1). [ka] (In the formula, R 1 , R 2 , R 3 and R 4 These may be identical or different from each other, and are selected from hydrogen atoms, halogen atoms, unsubstituted or substituted hydrocarbon groups, alkoxy groups, cyano groups, phenoxy groups, and nitro groups.

[0016] In the above general formula (1), R 1 , R 2 , R 3 or R 4When it is an unsubstituted hydrocarbon group, it can be an alkyl group, a phenyl group, etc. In the above general formula (1), R 1 , R 2 , R 3 or R 4 is a halogen atom, it may be any of Cl, Br and I. In the above general formula (1), R 1 , R 2 , R 3 or R 4 is an unsubstituted or substituted hydrocarbon group, the number of carbon atoms contained in the hydrocarbon group is preferably 1 to 8, more preferably 1 to 4. The unsubstituted hydrocarbon group may be either a saturated hydrocarbon group or an unsaturated hydrocarbon group. Further, examples of the substituted hydrocarbon group include a halogenated hydrocarbon group, a hydrocarbon group having an amino group, a hydrocarbon group having an alkoxy group, a hydrocarbon group having a cyano group, a hydrocarbon group having a phenoxy group, a hydrocarbon group having a nitro group, etc. In the above general formula (1), R 1 , R 2 , R [[ID=2k7]] 3 or R 4 is an alkoxy group, the number of carbon atoms contained in the hydrocarbon group constituting the alkoxy is preferably 1 to 8, more preferably 1 to 4.

[0017] Polyphenylene ether resins include poly(2,6-dimethyl-1,4-phenylene) ether, poly(2-methyl-6-ethyl-1,4-phenylene) ether, poly(2,6-diethyl-1,4-phenylene) ether, poly(2,6-ethyl-6-n-propyl-1,4-phenylene) ether, and poly(2,6-di-n-propyl-1,4-phenylene) ether, which consist of only one type of structural unit represented by the above general formula (1). Poly(2-methyl-6-n-butyl-1,4-phenylene) ether, poly(2-ethyl-6-isopropyl-1,4-phenylene) ether, poly(2-methyl-6-chloroethyl-1,4-phenylene) ether, poly(2-methyl-6-hydroxyethyl-1,4-phenylene) ether, poly(2-methyl-6-chloroethyl-1,4-phenylene) ether, poly(2,6-dimethoxy-1,4-phenylene) ether Examples include homopolymers such as poly(2,6-dichloromethyl-1,4-phenylene) ether, poly(2,6-dibromomethyl-1,4-phenylene) ether, poly(2,6-diphenyl-1,4-phenylene) ether, poly(2,6-ditril-1,4-phenylene) ether, poly(26-dichloro-1,4-phenylene) ether, poly(2,6-dibenzyl-1,4-phenylene) ether, and poly(2,5-dimethyl-1,4-phenylene) ether; and copolymers such as 2,6-dimethylphenol / 2,3,6-trimethylphenol copolymer, 2,6-dimethylphenol / 2,3,6-trimethylphenol copolymer, 2,6-diethylphenol / 2,3,6-trimethylphenol copolymer, and 2,6-dipropylphenol / 2,3,6-trimethylphenol copolymer, which consist of multiple types of structural units represented by the above general formula (1).

[0018] The molecular weight of the polyphenylene ether resin is not particularly limited. The number-average molecular weight determined by gel permeation chromatography (GPC) is preferably 30,000 to 100,000, more preferably 40,000 to 60,000.

[0019] Other resins constituting the polyphenylene ether resin according to the present invention include resins containing structural units derived from aromatic vinyl compounds (hereinafter referred to as "styrene resin"), polyamides, polyolefins, polyphenylene sulfide, polyphthalamides, and resins containing structural units derived from unsaturated acid anhydrides. The other resins included may be one or two or more. The content ratio of the polyphenylene ether resin and the other resins is preferably 30-70% by mass and 70-30% by mass, respectively, when the total of both is 100% by mass, and more preferably 40-60% by mass and 60-40% by mass. In the present invention, it is preferable that the polyphenylene ether resin and the other resins constitute an alloy resin.

[0020] In the present invention, the other resin is preferably a styrene resin. The styrene resin can be at least one selected from homopolymers, copolymers, and graft polymers obtained using aromatic vinyl compounds such as styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, and 1,3-dimethylstyrene. For example, polystyrene, rubber-modified polystyrene, ABS resin, styrene-acrylonitrile copolymer, styrene-acrylonitrile-methyl methacrylate copolymer, styrene-butadiene block copolymer, and hydrogenated styrene-butadiene block copolymer can be used.

[0021] When the polyphenylene ether-based resin according to the present invention consists of a polyphenylene ether resin and a styrene resin, it is preferable that the styrene resin is a graft polymer and forms a composite (alloy resin) that intertwines with the polyphenylene ether resin.

[0022] The styrene-based elastomer according to the present invention is at least one selected from styrene-ethylene-propylene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, and styrene-butadiene-styrene copolymer, with a styrene unit content of 25 to 65% by mass, preferably 35 to 65% by mass, and more preferably 40 to 65% by mass. Because the resin composition according to the present invention contains such a styrene-based elastomer, the piping member including the first pipe section exhibits excellent impact resistance and high strength.

[0023] In the resin composition according to the present invention, the content ratio of polyphenylene ether resin and styrene elastomer is not particularly limited, but in order to obtain the effects of the present invention to be fully obtained, when the total amount of both is 100% by mass, the content ratio is preferably 50 to 99% by mass and 1 to 50% by mass, respectively, and more preferably 70 to 98% by mass and 2 to 30% by mass.

[0024] The resin composition according to the present invention may consist of a polyphenylene ether resin and a styrene elastomer, or, as described above, may consist of a polyphenylene ether resin, a styrene elastomer, and other components.

[0025] Other components include polymer elastomers other than the styrene-based elastomers mentioned above, antioxidants, ultraviolet absorbers, light stabilizers, flame retardants, lubricants, antistatic agents, antibacterial agents, fillers, colorants, and the like. The resin composition according to the present invention may, for example, contain fibrous fillers in a proportion of 1 to 25% by mass depending on the application. However, if the filler is present in a proportion of 10% or more, the impact resistance of the first tube portion may be poor. Therefore, the filler may be omitted, or present in a proportion of less than 2% by mass, preferably less than 1% by mass, and more preferably less than 0.1% by mass.

[0026] The Charpy impact strength (with notch) of the resin composition according to the present invention is preferably 10 kJ / m at 23°C ± 1°C. 2 More preferably 20-50 kJ / m³ 2More preferably 25-45 kJ / m³ 2 Furthermore, at 80°C ± 1°C, the concentration is preferably 20 kJ / m³. 2 More preferably 25-70 kJ / m³ 2 More preferably 30-60 kJ / m 2 This Charpy impact strength can be measured by a method conforming to JIS K 7111.

[0027] The tensile modulus of the resin composition according to the present invention is preferably 1,000 to 3,000 MPa, more preferably 1,800 to 2,900 MPa, and even more preferably 2,000 to 2,800 MPa at 23°C ± 1°C. At 80°C ± 1°C, it is preferably 1,000 to 2,500 MPa, more preferably 1,250 to 2,200 MPa, and even more preferably 1,300 to 2,000 MPa. The tensile fracture strain is preferably 20 to 150%, more preferably 40 to 140%, at 23°C ± 1°C. At 80°C ± 1°C, it is preferably 80 to 180%, and even more preferably 100 to 170%. These tensile modulus and tensile fracture strain can be measured by a method in accordance with JIS K 7161.

[0028] The first pipe section is typically a molded article obtained by subjecting a molten resin composition to injection molding, extrusion molding, press molding, multilayer molding, etc. The resin composition according to the present invention contains a styrene-based elastomer with a styrene unit content of 25 to 65% by mass, and therefore exhibits excellent moldability. The MFR measured under conditions of a temperature of 260°C and a load of 10 kgf is preferably 6 to 25 g / 10 min, more preferably 9.5 to 24 g / 10 min.

[0029] The piping components of the present invention are applicable to all types of piping materials, but can be pipes, tubes, fittings, flanges, or valves. The line connecting one end of the piping component to the other end may be straight or curved (including wavy or spiral shapes). Furthermore, in the piping member 1 shown in Figures 1 and 2, the cross-sectional shape of the piping member through which the liquid flows (the shape depicted by the outline of the inner surface of the first pipe section) is a perfect circle, but it is not limited to this, and can be an ellipse, a polygon, or the like. Also, the inner surface of the first pipe section may have grooves in the longitudinal direction of the piping member. The average value of the inner diameter (bore diameter) of the cross-sectional shape of the piping member through which the liquid flows is preferably 10 to 500 mm.

[0030] In the present invention, the wall thickness of the first pipe section is preferably 2 mm or more, more preferably 2 to 25 mm, and even more preferably 2.5 to 20 mm, in the case of a single layer consisting only of the first pipe section. In the case of two or more layers, from the viewpoint of elution, it is preferably 1 mm or more, more preferably 1 to 20 mm, and even more preferably 1.5 to 15 mm. Furthermore, the wall thickness from one end to the other end of the piping member may be either uniform or non-uniform.

[0031] In the piping member of the present invention, it is preferable that the inner surface of the first pipe section has a portion with a surface roughness Rz of 0.5 μm or less. From the viewpoint of the fluidity of the liquid inside the piping member, it is particularly preferable that the surface roughness Rz of the entire inner surface is 0.5 μm or less. This surface roughness Rz is even more preferably 0.3 μm or less.

[0032] As described above, the piping member of the present invention may be provided with an outer covering, reinforcing part, etc., on at least a portion of the outer surface of the first pipe section. The constituent material of this outer covering 5 can be selected according to the purpose and may be resin, metal, etc. Furthermore, the outer covering and reinforcing part may consist of multiple layers.

[0033] The piping member of the present invention provides a high yield when various liquids are passed through it during product manufacturing (including treatments such as washing, acid washing, alkaline washing, sterilization, and disinfection). For example, it is suitable for applications such as cleaning semiconductors by supplying highly purified water, such as ultrapure water, or liquids containing predetermined components with controlled concentrations, using the piping member of the present invention. [Examples]

[0034] The present invention will be specifically described below with reference to examples.

[0035] 1. Raw materials for resin compositions for piping components The raw materials for the resin composition used in the manufacture of pipes as piping components are shown below.

[0036] 1-1. Polyphenylene ether resins (1) "Noril 731S-780F" (product name) manufactured by SHPP Japan LLC. It is an alloy resin containing polystyrene. (2) Asahi Kasei Corporation's "Zylon W5002" (product name) This is an alloy resin containing less than 40% by mass of polyphenylene ether and more than 40% by mass of polystyrene.

[0037] 1-2. Styrene-based elastomers (1) KRATON "D1155" (product name) This is a styrene-butadiene-styrene block copolymer with a styrene unit content of 40% by mass. (2) Asahi Kasei's "Toughprene A" (product name) This is a styrene-butadiene-styrene block copolymer with a styrene unit content of 40% by mass. (3) Kuraray Co., Ltd.'s "Septon 2104" (product name) This is a styrene-ethylene-propylene-styrene block copolymer with a styrene unit content of 65% by mass. (4) Asahi Kasei Corporation's "ToughTec H1051" (product name) This is a styrene-ethylene-butylene-styrene block copolymer with a styrene unit content of 42% by mass. (5) Kuraray Co., Ltd.'s "Septon 2004F" (product name) This is a styrene-ethylene-propylene-styrene block copolymer with a styrene unit content of 18% by mass. (6) Kraton "G1657" (product name) This is a styrene-ethylene-butylene-styrene block copolymer with a styrene unit content of 13% by mass.

[0038] 2. Manufacturing of resin compositions and pipes for piping components and evaluation thereof. Examples 1-13 and Comparative Examples 1-7 The above raw materials were kneaded in the proportions shown in Tables 1, 2, and 3 using a twin-screw extruder to form pellets (when using polyphenylene ether resin alone, the pelletized resin was used as is without kneading) to obtain resin compositions for piping components. Subsequently, MFR (temperature: 260°C or 230°C, load: 10 kgf) measurements were performed, Charpy impact strength (with notch) measurements were performed at 23°C±1°C and 80°C±1°C according to JIS K 7111, and tensile modulus and tensile fracture strain measurements were performed at 23°C±1°C and 80°C±1°C according to JIS K 7161. These results are listed in the respective tables. Furthermore, pipes (thickness: 3.1 mm, outer diameter: 32 mm, length: 1000 mm) were manufactured using the method described below, and then the inner surface roughness Rz (average value of 10 measurements) was measured using a roughness analyzer equipped with a diamond stylus (tip radius 2 mm).

[0039] <Pipe Manufacturing Method> Pellets of polyphenylene ether resin, or pellets formed by kneading polyphenylene ether resin and styrene elastomer as described in the examples, were used to form pipes made of the polyphenylene ether resin composition with a wall thickness of 3.1 mm and an outer diameter of 32 mm using a single-screw extruder at a cylinder temperature of 250°C.

[0040] For reference, commercially available polyvinylidene fluoride pipes were subjected to the same analysis or evaluation as described above, and the results are shown in Table 1.

[0041] [Table 1]

[0042] [Table 2]

[0043] [Table 3]

[0044] The following is clear from Tables 1 to 3. Examples 1 to 13 are examples using resin compositions containing styrene-based elastomers with a styrene unit content of 25 to 65% by mass, exhibiting excellent impact resistance and high strength against external forces. As a result, it is expected that liquids at temperatures of 120°C or lower can be supplied without problems through pipes, tubes, fittings, flanges, or valves obtained by molding the resin compositions of Examples 1 to 13. [Industrial applicability]

[0045] The piping component of the present invention can ensure a stable supply when various liquids at temperatures below 120°C are passed through it during product manufacturing or other processes. Taking advantage of this property, it is suitable as a piping component in equipment for manufacturing semiconductor-related products, electronic material-related products, liquid crystal-related products, pharmaceutical-related products, etc., or as a piping component for liquids supplied to such equipment. [Explanation of Symbols]

[0046] 1: Piping components 3: First Section 5:Exterior part

Claims

1. A piping member having a portion whose inner surface in contact with a liquid is made of a resin composition, The aforementioned resin composition contains a polyphenylene ether resin and a styrene elastomer. The styrene-based elastomer is at least one selected from styrene-ethylene-propylene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, and styrene-butadiene-styrene copolymer. A piping member characterized in that the amount of styrene units contained in the styrene-based elastomer is 25 to 65% by mass relative to the styrene-based elastomer.

2. The piping member according to claim 1, wherein the content of the styrene-based elastomer is 3 to 25% by mass relative to the resin composition.

3. The piping member according to claim 1, wherein the melt flow rate (260°C, 10 kgf) of the resin composition is 6.0 to 25 g / 10 min.

4. The piping member according to claim 1, wherein the inner surface has a portion having a surface roughness Rz of 0.5 μm or less.

5. The piping member according to claim 1, wherein the piping member is a pipe, tube, fitting, flange, or valve.

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