Method for manufacturing molded body and molded body

Abstract

To provide a method for manufacturing a molded body having low dielectric loss tangent and excellent appearance, the method enabling continuous manufacturing of the molded body at high manufacturing rate from raw material including a large amount of a polyphenylene ether-based resin.SOLUTION: A method for manufacturing a molded body includes: a step 1 of melting and kneading raw material including 55 mass% or more and 100 mass% or less of a polyphenylene ether-based resin (a), and 0 mass% or more and 45 mass% or less of a thermoplastic resin (b) having a dielectric loss tangent of 0.0015 or less at 10 ghz, using a single screw reciprocating extruder, thereby obtaining a thermoplastic resin composition in a molten state; and a step 2 of extruding the thermoplastic resin composition in the molten state obtained in the step 1 from a die or a nozzle connected to a resin discharge port of the single screw reciprocating extruder through a gear pump or a second extruder, and working the thermoplastic resin composition in a molded body selected from the group consisting of a film, a sheet, a fiber and a non-woven fabric.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a molded article and the molded article. [Background technology]

[0002] In recent years, with an increase in capacity and speed of information communication, communication signals have become increasingly higher in frequency. Since signal transmission loss is proportional to the product of the signal frequency, the dielectric tangent (Df) of the material, and the square root of the material's relative dielectric constant (√Dk), materials with both low dielectric tangent and relative dielectric constant are required. Polyphenylene ether resins have low dielectric tangents and dielectric constants, and therefore low signal transmission loss in the high frequency band. In addition, they also have excellent heat resistance, and therefore are increasingly being used as polymer insulating materials for circuit boards and other electronic components, such as antenna parts. For example, Patent Document 1 discloses a resin composition for components that contains a polyphenylene ether resin and is used in a frequency range of 1 GHz or more. Patent Document 2 discloses a film for high-frequency circuit substrates that is made of a thermoplastic resin composition containing a polyphenylene ether resin and has a dielectric loss tangent of 0.003 or less at 76.5 GHz. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-137491 A [Patent Document 2] Patent Publication No. 2011-253958 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the resin compositions and films disclosed in the above documents all have the problem that they are difficult to achieve a desired dielectric tangent when continuously produced at a high production rate. The present inventors have conducted research and found that, when a thermoplastic resin composition containing a large amount of polyphenylene ether-based resin is continuously produced at a high production rate, melt kneading using a commonly used twin-screw extruder causes large shear heat generation, which accelerates structural changes in the polyphenylene ether-based resin, making it difficult to maintain the low dielectric tangent that is a feature of the polyphenylene ether-based resin. In addition, it has been found that, when melt kneading is performed under low shear conditions by adjusting the extrusion conditions of the twin-screw extruder (e.g., cylinder barrel set temperature, total L / D of the screw kneading zone, screw rotation speed, etc.) or by using a single-screw extruder, shear heat generation is suppressed, but unmelted polyphenylene ether-based resin is generated due to insufficient kneading, resulting in poor appearance and reduced performance.

[0005] The present invention has an object to solve the above problems, and to provide a method for producing a molded article, which is made of a thermoplastic resin composition containing a large amount of a polyphenylene ether-based resin and has a low dielectric tangent and excellent appearance, and which enables continuous production at a high production rate of the molded article, and the molded article. [Means for solving the problem]

[0006] As a result of intensive research into solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by melt-kneading raw materials containing a polyphenylene ether-based resin using a single-screw reciprocating extruder, and extruding the raw materials from a die or nozzle connected to a resin outlet of the single-screw reciprocating extruder via a gear pump or a second extruder to process the raw materials into a molded product, thereby completing the present invention.

[0007] That is, the present invention is as follows. [1] A step 1 of melt-kneading raw materials including 55% by mass or more and 100% by mass or less of a polyphenylene ether-based resin (a) and 0% by mass or more and 45% by mass or less of a thermoplastic resin (b) having a dielectric tangent of 0.0015 or less at 10 GHz, using a single-screw reciprocating extruder, to obtain a molten thermoplastic resin composition; and Step 2, in which the molten thermoplastic resin composition obtained in step 1 is extruded through a die or a nozzle connected to a resin outlet of the single-screw reciprocating extruder via a gear pump or a second extruder, and processed into a molded article selected from the group consisting of a film, a sheet, a fiber, and a nonwoven fabric; A method for producing a molded body, comprising the steps of: [2] In the step 1, the maximum temperature of the content in the kneading zone of the single-screw reciprocating extruder is 350° C. or less, and The median residence time from when the raw material is fed into the single-screw reciprocating extruder in the step 1 to when the raw material is extruded as the molded body in the step 2 is 100 seconds or less. A method for producing the molded article described in [1]. [3] The method for producing a molded body according to [1] or [2], wherein the production rate is 20 kg / h or more. [4] The method for producing a molded article according to any one of [1] to [3], wherein the polyphenylene ether resin (a) has a weight average molecular weight of 30,000 or more. [5] The method for producing a molded article according to any one of [1] to [4], wherein the thermoplastic resin (b) is one or more selected from the group consisting of polystyrene, rubber-modified polystyrene, a styrene-based elastomer, a polyolefin, an olefin-based elastomer, a cyclic olefin polymer, and a liquid crystal polyester. [6] The method for producing a molded body according to any one of [1] to [5], wherein the raw materials contain 10 mass% or less of other additives (x) other than the polyphenylene ether-based resin (a) and the thermoplastic resin (b), relative to 100 mass% in total of the polyphenylene ether-based resin (a), the thermoplastic resin (b), and the other additives (x). [7] [1] to [6] are obtained by the method for producing a molded body, It has at least one glass transition temperature in a temperature range of 150°C or more and 250°C or less in differential scanning calorimetry, A molded article, in which the number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded article is an average of 1.3 or less per 100 monomer units constituting the polyphenylene ether resin (a') in the molded article. [8] The polyphenylene ether resin (a') in the molded product contains a repeating unit structure (i) represented by formula (1), a terminal structure (ii) represented by formula (2), and a rearrangement structure (iii) represented by formula (3), [ka] [ka] [ka] [In the formula, R 1 , R 3 , and R 4 are each independently a monovalent group selected from the group consisting of a hydrogen atom, a primary alkyl group having 1 to 7 carbon atoms, a secondary alkyl group having 1 to 7 carbon atoms, a tertiary alkyl group having 1 to 7 carbon atoms, and a phenyl group; R 2 is a monovalent group selected from the group consisting of a primary alkyl group having 1 to 7 carbon atoms, a secondary alkyl group having 1 to 7 carbon atoms, a tertiary alkyl group having 1 to 7 carbon atoms, and a phenyl group; R 2 ' is the R 2 It is a divalent group in which one hydrogen atom has been removed from . The molded body according to [7], wherein the sum of the number of OH groups derived from the terminal structure (ii) and the number of OH groups derived from the rearrangement structure (iii) is an average of 1.3 or less per 100 monomer units constituting the polyphenylene ether resin (a') in the molded body. [9] the number of OH groups derived from the terminal structure (ii) is 1.0 or less on average per 100 monomer units constituting the polyphenylene ether resin (a') in the molded product, the number of OH groups derived from the rearrangement structure (iii) is an average of 0.3 or less per 100 monomer units constituting the polyphenylene ether resin (a') in the molded product; [8] The molded article according to the present invention.

[10] The molded product according to any one of [7] to [9], wherein the polyphenylene ether resin (a') in the molded product has a weight average molecular weight of 55,000 or more.

[11] The molded product according to any one of [7] to

[10] , wherein the polyphenylene ether resin (a') in the molded product has a weight average molecular weight of 70,000 or more.

[12] [1] to [6] are obtained by the method for producing a molded body, It has at least one glass transition temperature in a temperature range of 150°C or more and 250°C or less in differential scanning calorimetry, A molded article having a dielectric tangent of 0.0025 or less at 10 GHz. Effect of the Invention

[0008] The method for producing a molded article of the present invention enables continuous production at a high production rate of a molded article made of a thermoplastic resin composition containing a large amount of a polyphenylene ether-based resin, which has a low dielectric tangent and excellent appearance. The obtained molded article has a low dielectric tangent and high heat resistance, and is also excellent in appearance, toughness, and chemical resistance, and can be suitably used as a film, sheet, fiber, and nonwoven fabric. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a mode for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described in detail. The following embodiment is an example for explaining the present invention, and the present invention is not limited to the following embodiment, and can be carried out in various modifications within the scope of the gist of the present invention.

[0010] (Method of Manufacturing Molded Product) The method for producing a molded article of the present embodiment includes step 1 of melt-kneading raw materials containing 55% by mass or more and 100% by mass or less of a polyphenylene ether resin (a) and 0% by mass or more and 45% by mass or less of a thermoplastic resin (b) having a dielectric tangent of 0.0015 or less at 10 GHz, relative to 100% by mass of the raw materials, using a single-screw reciprocating extruder to obtain a molten thermoplastic resin composition; and step 2 of extruding the molten thermoplastic resin composition obtained in step 1 through a die or nozzle connected to the resin outlet of the single-screw reciprocating extruder via a gear pump or a second extruder, and processing it into a molded article selected from the group consisting of films, sheets, fibers, and nonwoven fabrics. The method for producing a molded body of this embodiment may be a production method consisting of only the above steps 1 and 2, or may further include other steps.

[0011] -Polyphenylene ether resin (a)- The polyphenylene ether resin (a) is not particularly limited, and examples thereof include homopolymers having a repeating unit structure represented by formula (4) and copolymers containing the repeating unit structure. [ka] [In the formula, R 1 ~R 4 each independently represents any one selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 7 carbon atoms, a cycloalkyl group having 1 to 7 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group such as a phenyl group, a haloalkyl group, an aminoalkyl group, a hydrocarbonoxy group, and a halohydrocarbonoxy group (wherein at least two carbon atoms separate the halogen atom from the oxygen atom).

[0012] The polyphenylene ether resin (a) is not particularly limited, and known resins can be used. For example, homopolymers such as poly(2,6-dimethyl-1,4-phenylene ether), poly(2-methyl-6-ethyl-1,4-phenylene ether), poly(2-methyl-6-phenyl-1,4-phenylene ether), and poly(2,6-dichloro-1,4-phenylene ether); copolymers such as copolymers of 2,6-dimethylphenol with other phenols such as 2,3,6-trimethylphenol and 2-methyl-6-butylphenol; and the like. Among them, from the viewpoint of availability and various physical properties when molded into a molded product, poly(2,6-dimethyl-1,4-phenylene ether) and copolymers of 2,6-dimethylphenol and 2,3,6-trimethylphenol are preferred, and poly(2,6-dimethyl-1,4-phenylene ether) is more preferred. As the polyphenylene ether resin (a), these may be used alone or in combination of two or more.

[0013] The method for producing the polyphenylene ether resin (a) is not particularly limited, and examples thereof include the method by Hay of oxidatively polymerizing 2,6-xylenol using a mixture of a cuprous salt and an amine as a catalyst, as described in U.S. Pat. No. 3,306,874, and the methods described in U.S. Pat. Nos. 3,306,875, 3,257,357, 3,257,358, JP-B-17880 / 1977, JP-A-51197 / 1975, and JP-A-152628 / 1988.

[0014] The weight average molecular weight of the polyphenylene ether resin (a) is preferably 20,000 or more, more preferably 30,000 or more, and particularly preferably 40,000 or more from the viewpoint of heat resistance, toughness, and chemical resistance when molded into a molded article, and is preferably 80,000 or less, more preferably 70,000 or less, and particularly preferably 60,000 or less from the viewpoint of melt-kneadability. The weight average molecular weight can be determined by a conventionally known method using gel permeation chromatography (mobile phase: chloroform, standard substance: polystyrene).

[0015] -Thermoplastic resin (b)- The thermoplastic resin (b) is a thermoplastic resin having a dielectric loss tangent of 0.0015 or less at 10 GHz. From the viewpoint of the obtained molded article having a lower dielectric loss tangent, the thermoplastic resin (b) preferably has a dielectric loss tangent of 0.0010 or less at 10 GHz, more preferably 0.00080 or less, and particularly preferably 0.00050 or less. The dielectric tangent at 10 GHz may be a value measured by drying the thermoplastic resin (b) at 80°C or higher and 120°C or lower for 2 hours or higher and 4 hours or lower, and then injection molding or vacuum press molding a molded body of 50 mm x 50 mm x 0.95 mm, which is used as a sample, and leaving it in an atmosphere of 23°C x 50% RH for 24 hours or higher, and then measuring it in an atmosphere of 23°C x 50% RH by a resonator method.

[0016] The thermoplastic resin (b) is not particularly limited, and examples thereof include polystyrene, rubber-modified polystyrene, styrene-based elastomers, polyolefins, olefin-based elastomers, cyclic olefin polymers, and liquid crystal polyesters. These may be used alone or in combination of two or more. In addition, the thermoplastic resin (b) does not include polyphenylene ether resin.

[0017] Examples of the polystyrene include homopolymers and copolymers of styrene-based compounds such as styrene and α-methylstyrene, etc. These may have any stereoregularity of atactic, syndiotactic, or isotactic.

[0018] Examples of the rubber-modified polystyrene include copolymers obtained by polymerizing a styrene-based compound such as styrene or α-methylstyrene in the presence of a rubber polymer such as polybutadiene or polyisoprene, etc. These may be copolymers in which a part of the fatty chain double bonds in the rubber polymer is reduced by hydrogenation.

[0019] Examples of the styrene-based elastomer include block copolymers containing a polymer block whose main constituent unit is a styrene-based compound such as styrene or α-methylstyrene, and a polymer block whose main constituent unit is a conjugated diene compound such as butadiene or isoprene, etc. Also included are hydrogenated block copolymers in which part or all of the fatty chain double bonds in the block copolymer are reduced by hydrogenation.

[0020] Examples of the polyolefin include homopolymers and copolymers of α-olefin compounds such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene.

[0021] Examples of the olefin elastomer include copolymers of ethylene with an α-olefin compound such as 1-butene, 1-hexene, 4-methyl-1-pentene, or 1-octene.

[0022] Examples of the cyclic olefin polymer include an addition (co)polymer of a cyclic olefin represented by formula (5), an addition copolymer of a cyclic olefin represented by formula (5) and an α-olefin compound, a ring-opening (co)polymer of a cyclic olefin represented by formula (5), and a hydrogenated product thereof. [ka] [In the formula, R 11 ~R 22 may be the same or different and are selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, an alkoxycarbonyl group, an alkenyl group, an alkynyl group, a substituted or unsubstituted aryl group, an aralkyl group, and an alkylidene group; R 19 and R 20 , R 21 and R 22 may combine together to form a divalent hydrocarbon group, R 19 or R 20 And, R 21 or R 22 may form a ring together. n represents 0 or a positive integer, and when n is 2 or more, R 15 ~R 18 may be the same or different in each repeating unit.

[0023] Examples of the liquid crystal polyester include liquid crystal polyesters having p-hydroxybenzoic acid and polyethylene terephthalate as main structural units, liquid crystal polyesters having p-hydroxybenzoic acid and 2-hydroxy-6-naphthoic acid as main structural units, and liquid crystal polyesters having p-hydroxybenzoic acid, 4,4'-dihydroxybiphenyl, and terephthalic acid as main structural units.

[0024] The method for producing a molded article of this embodiment uses raw materials containing 55% by mass or more and 100% by mass or less of the polyphenylene ether resin (a) and 0% by mass or more and 45% by mass or less of the thermoplastic resin (b). As a result, the molded article obtained has a low dielectric tangent and high heat resistance. Preferably, the (a) is 60% by mass or more and 100% by mass or less and the (b) is 0% by mass or more and 40% by mass or less, more preferably, the (a) is 70% by mass or more and 100% by mass or less and the (b) is 0% by mass or more and 30% by mass or less.

[0025] -Other additives(x)- The raw material may be only the polyphenylene ether resin (a), or may be a mixture consisting of only the polyphenylene ether resin (a) and the thermoplastic resin (b). The raw material may further contain other additives (x). That is, the raw material may be a mixture consisting of only the polyphenylene ether resin (a) and the other additives (x), or may be a mixture consisting of only the polyphenylene ether resin (a), the thermoplastic resin (b), and the other additives (x). The resin components in the raw materials preferably consist only of the polyphenylene ether resin (a) and the thermoplastic resin (b). Examples of the other additives (x) include, but are not limited to, antioxidants, ultraviolet absorbers, light stabilizers, plasticizers, flame retardants, flame retardant assistants, crystal nucleating agents, inorganic fillers, organic fillers, hollow fillers, dyes, pigments, laser direct structuring additives, antistatic agents, antiblocking agents, lubricants, and the like. These may be used alone or in combination of two or more.

[0026] The amount of the other additives (x) is preferably 20% by mass or less, more preferably 10% by mass or less, and particularly preferably 5% by mass or less, relative to 100% by mass of the total of the polyphenylene ether resin (a), the thermoplastic resin (b), and the other additives (x).

[0027] -Step of obtaining a thermoplastic resin composition ("Step 1")- The method for producing a molded article of the present embodiment includes a step 1 in which the above-mentioned raw materials containing the polyphenylene ether resin (a) and the thermoplastic resin (b) are melt-kneaded using a single-screw reciprocating extruder to obtain a molten thermoplastic resin composition.

[0028] By using a single-screw reciprocating extruder for melt kneading, even when a thermoplastic resin composition containing a large amount of polyphenylene ether-based resin is continuously produced at a high production rate, it is possible to reduce shear heat generation during kneading, suppress structural changes in the polyphenylene ether-based resin, and maintain a low dielectric tangent of the resulting thermoplastic resin composition. Meanwhile, since necessary and sufficient kneading is performed, it is possible to prevent the occurrence of unmelted polyphenylene ether-based resin.

[0029] In this embodiment, the term "thermoplastic resin composition containing a large amount of polyphenylene ether-based resin" refers to a composition containing 55% by mass or more and 100% by mass or less of polyphenylene ether-based resin (a) relative to 100% by mass of the above raw materials. The mass proportion of the polyphenylene ether resin (a) is preferably 60 mass % or more, more preferably 70 mass % or more, and may be less than 100 mass %.

[0030] In this embodiment, a "high production rate" refers to a production rate of 20 kg / h or more. The production rate in the production method of this embodiment is preferably 40 kg / h or more, more preferably 60 kg / h or more, particularly preferably 80 kg / h or more, and most preferably 100 kg / h or more.

[0031] The single-screw reciprocating extruder is characterized in that the screw rotates in the circumferential direction while reciprocating back and forth in the axial direction at the same time, and has protruding pins at multiple locations inside the cylinder barrel of the extruder, and kneading is performed between the pins and the screw threads. There are no particular limitations on the single-screw reciprocating extruder, but the COMPEO series (COMPEO Labo, COMPEO55, COMPEO88, COMPEO110, COMPEO137, COMPEO176) manufactured by BUSS is preferred.

[0032] The magnitude of shear heat generated during melt kneading can be indexed by the temperature of the contents in the kneading zone of the single-screw reciprocating extruder measured by a thermocouple attached inside the pin. From the viewpoint of suppressing structural changes in the polyphenylene ether resin and maintaining a low dielectric tangent of the resulting molded article, the maximum temperature of the contents in the kneading zone is preferably 350°C or less, more preferably 345°C or less, and particularly preferably 340°C or less. On the other hand, from the viewpoint of preventing the generation of unmelted polyphenylene ether resin, it is preferably 280°C or more, more preferably 290°C or more, and particularly preferably 300°C or more.

[0033] The temperature of the contents in the kneading zone is appropriately adjusted within the above-mentioned range by adjusting the cylinder barrel set temperature, screw set temperature, total L / D of the screw kneading zone, screw rotation speed, etc. of the single-screw reciprocating extruder.

[0034] The cylinder barrel set temperature is preferably 250°C or higher and 320°C or lower, more preferably 260°C or higher and 315°C or lower, and particularly preferably 270°C or higher and 310°C or lower.

[0035] In the case of the COMPEO series, unlike commonly used twin-screw extruders and single-screw extruders, a heat transfer medium circulates inside the screw shaft, making it possible to adjust the screw temperature. The screw temperature is preferably set to 200°C or higher and 280°C or lower, more preferably 220°C or higher and 260°C or lower, and particularly preferably 230°C or higher and 250°C or lower.

[0036] The screw has at least one conveying zone, the main purpose of which is to convey the raw materials or molten resin downstream, and at least one kneading zone, the main purpose of which is to knead the raw materials or molten resin. The total L / D of the screw kneading zones (L is the screw length (unit: mm), and D is the screw diameter (unit: mm)) is preferably 5 to 20, more preferably 10 to 15.

[0037] The screw rotation speed is preferably 200 rpm or more and 550 rpm or less, more preferably 250 rpm or more and 500 rpm or less, and particularly preferably 300 rpm or more and 450 rpm or less, from the viewpoint of performing necessary and sufficient kneading while reducing shear heat during melt kneading.

[0038] In step 1, the residence time from when the raw materials are fed into the single-screw reciprocating extruder until they reach the resin outlet is preferably 45 seconds or less, more preferably 35 seconds or less, and particularly preferably 25 seconds or less, as a median, from the viewpoint of further suppressing structural changes in the polyphenylene ether resin and further maintaining a low dielectric tangent of the resulting molded article. The median residence time can be determined by measuring the time from when a tracer is added into the single-screw reciprocating extruder during extrusion under specified conditions to when the tracer comes out of the resin outlet and when the tracer finishes coming out.

[0039] -Processing into a molded product ("Process 2")- The method for producing a molded article of the present embodiment includes step 2 of extruding the molten thermoplastic resin composition obtained in step 1 from a die or nozzle connected to a resin outlet of the single-screw reciprocating extruder via a gear pump or a second extruder, and processing the composition into a molded article selected from the group consisting of films, sheets, fibers, and nonwoven fabrics. Between step 1 and step 2, there is no step of solidifying or remelting the molten thermoplastic resin composition obtained in step 1.

[0040] By subsequently processing the molten thermoplastic resin composition obtained in step 1 into a molded article in step 2, the time during which the composition is exposed to a high-temperature molten state is shortened, the structural change of the polyphenylene ether resin is further suppressed, and the dielectric tangent of the obtained molded article can be maintained even lower.

[0041] For example, the median residence time from when the raw material is fed into the single-screw reciprocating extruder in step 1 to when it is extruded as a molded product in step 2 is preferably 100 seconds or less, more preferably 80 seconds or less, and particularly preferably 60 seconds or less. The median residence time can be determined by measuring the time from when a tracer is added to the single-screw reciprocating extruder during extrusion under specified conditions to when it is extruded as a molded product from a die or nozzle, and the time to when it is completely extruded. More specifically, it can be determined by the method described in the Examples below.

[0042] Since the single-screw reciprocating extruder has a mechanism in which the screw reciprocates in the axial direction, the discharge rate is not stable. Therefore, it is common to connect a gear pump or a second extruder to the resin outlet of the single-screw reciprocating extruder to increase the pressure of the molten resin, and then extrude it through a die, nozzle, etc. Therefore, in the above step 2, the resin is extruded from a die or nozzle connected to the resin outlet of the above single-screw reciprocating extruder via a gear pump or a second extruder, and processed into a molded article selected from the group consisting of a film, a sheet, a fiber, and a nonwoven fabric. From the viewpoints of shortening the time of exposure to a high-temperature molten state, further suppressing structural changes of the polyphenylene ether resin, and maintaining a further low dielectric loss tangent of the obtained molded article, it is preferable to use a gear pump. The second extruder may be a twin screw extruder or a single screw extruder. The cylinder barrel set temperature is preferably 250° C. or more and 320° C. or less, more preferably 260° C. or more and 315° C. or less, and particularly preferably 270° C. or more and 310° C. or less. The screw rotation speed is preferably 5 rpm or more and 100 rpm or less, and more preferably 10 rpm or more and 50 rpm or less. In the above step 2, a screen mesh or the like may be attached at any position for the purpose of removing unmelted or charred polyphenylene ether resin (a) and foreign matter resulting from the raw materials or the manufacturing process.

[0043] In the present embodiment, the method for processing into a molded article is not particularly limited, but examples thereof include the following manufacturing method. A method of molding a film or sheet by connecting a gear pump or a second extruder to the resin outlet of a single-screw reciprocating extruder and connecting a T-die downstream of it. In this case, the film or sheet may be used as is, or may be uniaxially stretched in the longitudinal or transverse direction, or may be biaxially stretched. A method of spinning fibers by connecting a gear pump or a second extruder to the resin outlet of a single-screw reciprocating extruder and connecting a melt spinning nozzle downstream of the gear pump or a second extruder. In this case, the fibers may be used as is or may be stretched. The melt-spun fibers may also be accumulated to form a nonwoven fabric.

[0044] (Molded body) The molded article of this embodiment is a molded article obtained by the above-mentioned method for producing a molded article of this embodiment. The above-mentioned molded article is obtained by the above-mentioned manufacturing method for a molded article of the present embodiment, and preferably has at least one glass transition temperature in a temperature range of 150°C or higher and 250°C or lower in differential scanning calorimetry, and the number of OH groups contained in the structure of the polyphenylene ether-based resin (a') in the molded article is an average of 1.3 or less per 100 monomer units constituting the polyphenylene ether-based resin (a') in the molded article.

[0045] The molded article has high heat resistance because the glass transition temperature measured by a differential scanning calorimeter is 150°C or higher. The glass transition temperature is preferably 160°C or higher, more preferably 170°C or higher, particularly preferably 180°C or higher, and most preferably 190°C or higher. In addition, the molded article has high processability because the glass transition temperature is 250°C or lower. The glass transition temperature is preferably 240°C or lower, more preferably 230°C or lower, and particularly preferably 220°C or lower.

[0046] -Polyphenylene ether resin (a') in molded product- In this embodiment, the polyphenylene ether resin (a) undergoes a structural change through the above steps 1 and 2, and exists in the molded product in the form of polyphenylene ether resin (a').

[0047] Here, the structural change from polyphenylene ether resin (a) to polyphenylene ether resin (a') in the molded product will be explained using poly(2,6-dimethyl-1,4-phenylene ether) as an example. It is known that polyphenylene ether resins undergo a rearrangement reaction represented by the following formula (6) at high temperatures of about 300°C or higher. In this rearrangement reaction, new OH groups are generated at the rearranged portion. As a result of the increase in the number of OH groups per molecule of polyphenylene ether resin, the polarity of the molecule increases, and it is believed that the low dielectric tangent, which is a feature of polyphenylene ether resins, is impaired. [ka] The number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded article is preferably 1.3 or less on average, more preferably 1.2 or less, even more preferably 1.1 or less, and particularly preferably 1.0 or less, per 100 monomer units constituting the polyphenylene ether resin (a') in the molded article. By adjusting the number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded article to fall within the above range, a molded article having a low dielectric tangent can be obtained. The number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded body can be determined using a proton nuclear magnetic resonance spectrum. In the proton nuclear magnetic resonance spectrum chart, when the peak of the polyphenylene ether resin (a') in the molded body overlaps with the peak of the polyphenylene ether resin (a') in the molded body other than the polyphenylene ether resin (a') in the molded body, and the number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded body cannot be determined, the molded body is dissolved in a good solvent for the polyphenylene ether resin such as benzene, toluene, xylene, dichloromethane, chloroform, etc., and then a poor solvent for the polyphenylene ether resin such as methanol, ethanol, acetone, tetrahydrofuran is added to precipitate and separate only the polyphenylene ether resin (a') in the molded body, and the polyphenylene ether resin is subjected to proton nuclear magnetic resonance spectroscopy. Specifically, for example, it can be determined by the method described in the examples described later.

[0048] The polyphenylene ether resin (a') in the molded product contains a repeating unit structure (i) represented by formula (1), a terminal structure (ii) represented by formula (2), and a rearrangement structure (iii) represented by formula (3). The sum of the number of OH groups derived from the above structure (ii) and the above structure (iii) is preferably 1.3 or less on average per 100 monomer units constituting the polyphenylene ether resin (a') in the molded article.

[0049] More preferably, the number of OH groups derived from the structure (ii) in the polyphenylene ether resin (a') in the molded article is 1.0 or less on average per 100 monomer units constituting the polyphenylene ether resin (a') in the molded article, and the number of OH groups derived from the structure (iii) is 0.3 or less on average per 100 monomer units constituting the polyphenylene ether resin (a') in the molded article. By adjusting the ratio within the above ranges, a molded article having excellent strength, toughness, and chemical resistance in addition to a low dielectric tangent can be obtained. [ka] [ka] [ka] [In the formula, R 1 , R 3 , and R 4 are each independently a monovalent group selected from the group consisting of a hydrogen atom, a primary alkyl group having 1 to 7 carbon atoms, a secondary alkyl group having 1 to 7 carbon atoms, a tertiary alkyl group having 1 to 7 carbon atoms, and a phenyl group; R 2 is a monovalent group selected from the group consisting of a primary alkyl group having 1 to 7 carbon atoms, a secondary alkyl group having 1 to 7 carbon atoms, a tertiary alkyl group having 1 to 7 carbon atoms, and a phenyl group; R 2 ' is the above R 2 It is a divalent group in which one hydrogen atom has been removed from .

[0050] The weight average molecular weight of the polyphenylene ether resin (a') in the molded article is preferably not less than 55,000, and more preferably not less than 70,000. By adjusting it within the above range, a molded article having excellent strength, toughness, and chemical resistance can be obtained.

[0051] The molded article is obtained by the above-mentioned molded article manufacturing method, has at least one glass transition temperature in a temperature range of 150° C. to 250° C. in differential scanning calorimetry, and has a dielectric loss tangent of 0.0025 or less at 10 GHz. The dielectric loss tangent of 0.0025 or less results in a molded article with small signal transmission loss in the high frequency band. The dielectric loss tangent can be determined by the method described in the examples below. EXAMPLES

[0052] The present invention will be described below with reference to specific examples and comparative examples, but the present invention is not limited to these.

[0053] The raw materials used in the examples and comparative examples described below are shown below. -Polyphenylene ether resin (a)- (a-1) Poly(2,6-dimethyl-1,4-phenylene ether) (weight average molecular weight: 38,000) (a-2) Poly(2,6-dimethyl-1,4-phenylene ether) (weight average molecular weight: 52,000) -Thermoplastic resin (b)- (b-1) Atactic homopolystyrene (product name: Polystyrene 685, manufactured by PS Japan) (dielectric tangent at 10 GHz: 0.00037) (b-2) High impact polystyrene (product name: Polystyrene H9405, manufactured by PS Japan) (dielectric tangent at 10 GHz: 0.00080) The dielectric loss tangent at 10 GHz was measured by drying (b-1) and (b-2) at 80°C for 3 hours, and then vacuum pressing them at 180°C to obtain a molded body of 50 mm x 50 mm x 0.95 mm. The molded body was left to stand in an atmosphere of 23°C x 50% RH for 24 hours or more, and then measured in an atmosphere of 23°C x 50% RH in the same manner as in the measurement method of the dielectric loss tangent of a molded body described later. -Other additives(x)- (x-1) Antioxidant (product name: Irganox565, manufactured by BASF) (x-2) Antioxidant (product name: Irgafos168, manufactured by BASF)

[0054] The methods (1) to (5) for measuring the physical properties used in the examples and comparative examples are shown below.

[0055] (1) Weight average molecular weight The weight average molecular weight of the polyphenylene ether resin (a) and the weight average molecular weight of the polyphenylene ether resin (a') in the molded product were measured using gel permeation chromatography (model: LC2030S, manufactured by Shimadzu Corporation) under the following conditions, using a calibration curve prepared using standard polystyrene (molecular weights: 3,650,000, 2,170,000, 1,090,000, 681,000, 204,000, 52,000, 30,200, 13,800, 3,360, 1,300, 550). Column: Two K-805L columns (Showa Denko) connected in series Solvent: Chloroform Flow rate: 1.0mL / min Column temperature: 40℃ Detection wavelength (standard polystyrene): 254 nm Detection wavelength (polyphenylene ether resin): 283 nm The weight average molecular weight was calculated from the ratio of the peak area of ​​the obtained curve showing the molecular weight distribution.

[0056] (2) The number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded product Small pieces were cut out from the sheet-like molded bodies obtained in Example 1 and Comparative Example 2, dissolved in chloroform deuterium oxide to a concentration of 3 wt / vol%, and the spectrum was measured under the following conditions using a nuclear magnetic resonance apparatus (model: AvanceNEO600, manufactured by Bruker). Measurement nuclei: 1 H Measurement frequency: 600MHz Number of times accumulated: 1024 Measurement temperature: room temperature The sheet-like molded bodies obtained in Example 2, Example 3, Comparative Example 1, Comparative Example 3, and Comparative Example 4 were dissolved in chloroform, and then acetone in an amount three times that of chloroform was gradually added to precipitate the polyphenylene ether resin (a') in the molded body. The precipitate was dried, and then dissolved in a deuterated solvent of chloroform to a concentration of 3 wt / vol%, and a spectrum was measured under the above conditions using a nuclear magnetic resonance apparatus (model: AvanceNEO600, manufactured by Bruker). From the obtained spectrum chart, the integral value [α] of the peak at a chemical shift of 6.2 to 6.8 ppm where the protons of the 3- and 5-positions of the aromatic ring of poly(2,6-dimethyl-1,4-phenylene ether) appear, the integral value [β] of the peak at a chemical shift of 4.1 to 4.3 ppm where the protons of the OH group of the terminal structure (ii) appear, and the integral value [γ] of the peak at a chemical shift of 4.3 to 4.5 ppm where the protons of the OH group of the rearrangement structure (iii) appear were determined, and the number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded product (average value per 100 monomer units constituting the polyphenylene ether resin) was calculated according to the following formulas (I), (II), and (III). Number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded product (average value for 100 monomer units constituting the polyphenylene ether resin (a') in the molded product) = ([β] + [γ]) / ([α] / 2) × 100 (I) The number of OH groups originating from the terminal structure (ii) contained in the structure of the polyphenylene ether resin (a') in the molded product (average value per 100 monomer units constituting the polyphenylene ether resin (a') in the molded product) = [β] / ([α] / 2) × 100 (II) The number of OH groups derived from the rearrangement structure (iii) contained in the structure of the polyphenylene ether resin (a') in the molded body (average value per 100 monomer units constituting the polyphenylene ether resin (a') in the molded body) = [γ] / ([α] / 2) × 100 (III)

[0057] (3) Dielectric tangent and relative dielectric constant of the molded body From the sheet-like molded bodies obtained in the Examples and Comparative Examples, 50 mm x 50 mm x 0.95 mm pieces were cut out and left to stand for 24 hours or more under an atmosphere of 23°C x 50% RH, and then the dielectric tangent and relative dielectric constant were measured under the following conditions using a network analyzer (model: N5224B, Keysight Technologies, Inc.) under an atmosphere of 23°C x 50% RH. The lower the values ​​of the dielectric tangent and relative dielectric constant, the better the product was judged to be. Resonator: Split post dielectric resonator (model: N1501AE19, Keysight Technologies) Measurement frequency: 10GHz

[0058] (4) Glass transition temperature of molded product Small pieces were cut out from the sheet-like molded bodies obtained in the Examples and Comparative Examples, and scanned under a nitrogen atmosphere using a differential scanning calorimeter (model: DSC8000, manufactured by PerkinElmer) with the following temperature program. The glass transition temperature was read from the chart after the second temperature rise. It was determined that the higher the glass transition temperature, the better the heat resistance. Temperature program: 1st temperature rise (0 → 230 ° C, 20 ° C / min) → Temperature drop (230 → 0 ° C, 20 ° C / min) → 2nd temperature rise (0 → 230 ° C, 20 ° C / min) → Temperature drop (230 → 0 ° C, 20 ° C / min)

[0059] (5) Appearance of the molded product The sheet-like molded products obtained in the Examples and Comparative Examples were attached to a heating vacuum molding machine (manufactured by Showa Denki) to mold a hat-shaped film. The obtained film was cut into a size of 10 cm x 10 cm, placed on a light box, and observed for the presence or absence of unmelted material, and judged according to the following criteria. Good: The number of unmelted objects with a size of 0.2 mm or more is 0. Defective: There is one or more unmelted objects with a size of 0.2 mm or more.

[0060] (Examples 1 to 3, Comparative Example 1) As the melt kneading device, a single-screw reciprocating extruder (model: COMPEO55, manufactured by BUSS) was used. A raw material supply port was provided on the upstream side of the raw material flow direction, and three kneading zones were provided downstream of the raw material supply port. Thermocouples were installed in the kneading zones to measure the temperature of the contents, and a vacuum vent was installed downstream of the kneading zones. A T-die was connected to the resin discharge port of the single-screw reciprocating extruder via a gear pump. Nitrogen gas was sealed into the raw material supply port, and the oxygen concentration was adjusted to 8% by volume or less. The barrel temperature was set to 280°C, the screw temperature to 240°C, the vacuum vent pressure reduction to -0.06 MPa·G, and the T-die temperature to 280°C. Melt kneading and sheet forming were performed according to the raw material composition and kneading conditions shown in Table 1, and a sheet with a thickness of 0.95 mm was obtained. The residence time from when the raw materials were supplied to the raw material supply port of the single-screw reciprocating extruder until they were extruded from the T-die as a sheet molding was calculated as the median value between [t1] and [t2], starting from the moment when a calcium carbonate masterbatch was added as a tracer into the single-screw reciprocating extruder during extrusion according to Table 1. The measurement was started by measuring the time [t1] until the white-colored sheet molding was extruded and the time [t2] until the white-colored sheet molding was completely discharged.

[0061] Comparative Example 2 As the melt kneader, a twin-screw extruder (model: ZSK-25, manufactured by COPERION) was used. A raw material supply port was provided on the upstream side of the flow direction of the raw materials, and three kneading zones were provided downstream of the raw material supply port. Thermocouples were installed in the kneading zones to measure the temperature of the contents, and a vacuum vent was installed downstream of the kneading zones. A strand die was connected to the resin outlet of the twin-screw extruder. Nitrogen gas was sealed into the raw material supply port, and the oxygen concentration was adjusted to 8% by volume or less. The barrel temperature was set to 290°C, and the vacuum level was set to -0.06 MPa·G. Melt-kneading and granulation were performed according to the raw material composition and kneading conditions shown in Table 1, to obtain pellets. The obtained pellets were dried at 90° C. for 3 hours, and then a test piece of 100 mm×100 mm×0.95 mm was obtained using an injection molding machine (model: EC75SXIII, manufactured by Shibaura Machine Co., Ltd.).

[0062] Comparative Example 3 As the melt kneader, a twin-screw extruder (model: TEM-58SX, manufactured by Shibaura Machine Co., Ltd.) was used. A raw material supply port was provided on the upstream side of the flow direction of the raw materials, and three kneading zones were provided downstream of the raw material supply port. Thermocouples were installed in the kneading zones to measure the temperature of the contents, and a vacuum vent was installed downstream of the kneading zones. A strand die was connected to the resin outlet of the twin-screw extruder. Nitrogen gas was sealed into the raw material supply port and the oxygen concentration was adjusted to 8% by volume or less. The barrel temperature was set at 300°C and the vacuum level was set at -0.06 MPa·G. Melt-kneading and granulation were performed according to the raw material composition and kneading conditions shown in Table 1 to obtain pellets. The obtained pellets were dried at 90° C. for 3 hours, and then a test piece of 100 mm×100 mm×0.95 mm was obtained using an injection molding machine (model: EC75SXIII, manufactured by Shibaura Machine Co., Ltd.).

[0063] Comparative Example 4 As the melt kneader, a twin-screw extruder (model: ZSK-25, manufactured by COPERION) was used. A raw material supply port was provided on the upstream side of the flow direction of the raw materials, and two kneading zones were provided downstream of the raw material supply port. A thermocouple was installed in the kneading zone to measure the temperature of the contents, and a vacuum vent was installed downstream of the kneading zone. A strand die was connected to the resin discharge port of the twin-screw extruder. Nitrogen gas was sealed into the raw material supply port, and the oxygen concentration was adjusted to 8% by volume or less. The barrel temperature was set to 270°C, and the vacuum level was set to -0.06 MPa·G. Melt-kneading and granulation were performed according to the raw material composition and kneading conditions shown in Table 1, to obtain pellets. The obtained pellets were dried at 90° C. for 3 hours, and then a test piece of 100 mm×100 mm×0.95 mm was obtained using an injection molding machine (model: EC75SXIII, manufactured by Shibaura Machine Co., Ltd.).

[0064] [Table 1]

Claims

1. A step 1 of melt-kneading raw materials including 55% by mass or more and 100% by mass or less of a polyphenylene ether-based resin (a) and 0% by mass or more and 45% by mass or less of a thermoplastic resin (b) having a dielectric tangent of 0.0015 or less at 10 GHz using a single-screw reciprocating extruder to obtain a molten thermoplastic resin composition; and Step 2, in which the molten thermoplastic resin composition obtained in step 1 is extruded through a die or a nozzle connected to a resin outlet of the single-screw reciprocating extruder via a gear pump or a second extruder, and processed into a molded article selected from the group consisting of a film, a sheet, a fiber, and a nonwoven fabric; A method for producing a molded body, comprising the steps of:

2. In the step 1, the maximum temperature of the content in the kneading zone of the single-screw reciprocating extruder is 350° C. or less, and The median residence time from when the raw material is supplied into the single-screw reciprocating extruder in the step 1 to when the raw material is extruded as the molded body in the step 2 is 100 seconds or less. A method for producing the molded article according to claim 1.

3. The method for producing a molded article according to claim 1 or 2, wherein the production rate is 20 kg / h or more.

4. The method for producing a molded article according to claim 1 or 2, wherein the polyphenylene ether resin (a) has a weight average molecular weight of 30,000 or more.

5. 3. The method for producing a molded article according to claim 1 or 2, wherein the thermoplastic resin (b) is one or more selected from the group consisting of polystyrene, rubber-modified polystyrene, a styrene-based elastomer, a polyolefin, an olefin-based elastomer, a cyclic olefin polymer, and a liquid crystal polyester.

6. 3. The method for producing a molded body according to claim 1 or 2, wherein the raw materials contain 10 mass% or less of other additives (x) other than the polyphenylene ether-based resin (a) and the thermoplastic resin (b), relative to 100 mass% in total of the polyphenylene ether-based resin (a), the thermoplastic resin (b), and the other additives (x).

7. A molded article obtained by the method for producing a molded article according to claim 1, It has at least one glass transition temperature in a temperature range of 150° C. or more and 250° C. or less in differential scanning calorimetry, A molded article, wherein the number of OH groups contained in the structure of the polyphenylene ether resin (a') in the molded article is an average of 1.3 or less per 100 monomer units constituting the polyphenylene ether resin (a') in the molded article.

8. The polyphenylene ether resin (a') in the molded product contains a repeating unit structure (i) represented by formula (1), a terminal structure (ii) represented by formula (2), and a rearrangement structure (iii) represented by formula (3), 【Chemistry 1】 【Chemistry 2】 【Chemistry 3】 [In the formula, R １ , R ３ , and R ４ are each independently a monovalent group selected from the group consisting of a hydrogen atom, a primary alkyl group having 1 to 7 carbon atoms, a secondary alkyl group having 1 to 7 carbon atoms, a tertiary alkyl group having 1 to 7 carbon atoms, and a phenyl group; R ２ is a monovalent group selected from the group consisting of a primary alkyl group having 1 to 7 carbon atoms, a secondary alkyl group having 1 to 7 carbon atoms, a tertiary alkyl group having 1 to 7 carbon atoms, and a phenyl group; R ２ ' is the above R ２ is a divalent group in which one hydrogen atom has been removed from 8. The molded article according to claim 7, wherein the sum of the number of OH groups derived from the terminal structure (ii) and the number of OH groups derived from the rearrangement structure (iii) is an average of 1.3 or less per 100 monomer units constituting the polyphenylene ether resin (a') in the molded article.

9. the number of OH groups derived from the terminal structure (ii) is 1.0 or less on average per 100 monomer units constituting the polyphenylene ether resin (a′) in the molded product, the number of OH groups derived from the rearrangement structure (iii) is an average of 0.3 or less per 100 monomer units constituting the polyphenylene ether resin (a′) in the molded product; The molded article according to claim 8.

10. 8. The molded article according to claim 7, wherein the polyphenylene ether resin (a') in the molded article has a weight average molecular weight of 55,000 or more.

11. 8. The molded article according to claim 7, wherein the polyphenylene ether resin (a') in the molded article has a weight average molecular weight of 70,000 or more.

12. A molded article obtained by the method for producing a molded article according to claim 1, It has at least one glass transition temperature in a temperature range of 150° C. or more and 250° C. or less in differential scanning calorimetry, A molded body having a dielectric tangent of 0.0025 or less at 10 GHz.

Images