Method for producing resin composition and apparatus for producing resin composition

Abstract

A method for producing a resin composition, the method including: a step for preparing a specific kneading extruder including a cylinder (1) provided so that devolatilization aid supply ports (11A, 11B) and devolatilization ports (12A, 12B) for discharging volatile components satisfy specific conditions, and a screw (2) having a specific screw structure in which seal rings (SR1-4) are disposed at specific positions; and a feeding and kneading step for feeding and kneading the raw material supplied into the cylinder (1) using the kneading extruder, in which the filling rate of the raw material is 70% or more in at least one of specific regions (A1, A2) in the cylinder (1), the devolatilization aid (DA) is supplied to the raw material in the cylinder (1) from devolatilization aid supply ports (11A, 11B), and the devolatilization aid (DA) is supplied to the raw material in the cylinder (1) from the devolatilization aid supply ports (11A, 11B), and the devolatilization aid (DA) is supplied to the raw material in the cylinder (1) from the devolatilization aid supply ports (11A, 11B) in at least one of the specific regions (A1, A2) in the cylinder (1). Volatile components contained in the raw material are discharged from the devolatilization ports (12A, 12B) to obtain the resin composition.

Description

TECHNICAL FIELD

[0001] The present application relates to a resin composition manufacturing method and a resin composition manufacturing apparatus. BACKGROUND

[0002] In the past, in the field of resin compositions, in order to remove volatile organic compounds (VOC) such as residual solvents, residual monomers, etc. contained in the composition, it has been proposed to manufacture resin compositions using a mixing extruder capable of performing devolatilization treatment. Furthermore, in recent years, from the viewpoint of environmental protection and the like, there is a strong demand in society to recycle resin compositions, and there is a demand to recycle and utilize resin compositions, but in manufacturing such recycled resin compositions, in order to remove volatile organic compounds contained in the resin compositions, it has also been proposed to manufacture (recycled) resin compositions using a mixing extruder capable of performing devolatilization treatment.

[0003] As a method of manufacturing resin compositions using such a mixing extruder capable of performing devolatilization treatment, for example, in Patent Literature 1 (Japanese Patent Application Publication No. 2021-62552), a resin composition manufacturing method is disclosed, which has the following steps: (a) preparing an extruder having a cylinder, a screw rotatably provided in the cylinder, a rotation drive mechanism that rotates the screw, a melt mixing section, a devolatilization section, which are sequentially arranged from the upstream side; (b) mixing a molten resin obtained by melting a thermoplastic resin and an additive in the melt mixing section of the extruder; (c) adding a devolatilization aid and mixing in the first section of the devolatilization section of the extruder, thereby dispersing the devolatilization aid in the thermoplastic resin; (d) providing a reduced pressure state in the second section of the devolatilization section of the extruder, thereby removing volatile components from the mixture of the thermoplastic resin and the additive together with the devolatilization aid. In addition, in Non-Patent Literature 1 (brochure (NL-J0014-02) of Resin Machinery Division, Hiroshima Works, Nippon Steel & Sumikin Steel Co., Ltd., "Introduction of TEX Water Addition Devolatilization Effect", Internet <URL: https: / / www.jsw.co.jp / ja / product / news / details / 20211001000006.html>), as a screw design suitable for low viscosity resins, a technology using a mixing extruder provided with a seal ring before and after the water addition section is disclosed.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Publication No. 2021-62552

[0007] NON-PATENT LITERATURE

[0008] Non-Patent Literature 1: Brochure (NL-J0014-02) "Introduction of TEX Water Addition and Devolatilization Effects" by Nippon Steel & Sumikin Materials Co., Ltd., Internet <URL: https: / / www.ipros.jp / catalog / detail / 557129 / > SUMMARY

[0009] PROBLEMS TO BE SOLVED BY THE INVENTION

[0010] However, the conventional resin composition production method described in Patent Literature 1 and Non-Patent Literature 1 is not sufficient in reducing the residual amount of volatile organic compounds in the obtained resin composition.

[0011] The present application was achieved in view of the problems of the conventional technology, and aims to provide a resin composition production method capable of efficiently producing a resin composition having a sufficiently low residual amount of volatile organic compounds, and a resin composition production apparatus capable of being appropriately used for the method.

[0012] MEANS FOR SOLVING THE PROBLEMS

[0013] The present inventors and others have repeatedly conducted intensive research in order to achieve the object, and as a result, have found that a resin composition having a sufficiently low residual amount of volatile organic compounds can be efficiently and reliably produced by the following method, thereby completing the present application:

[0014] a mixing extruder satisfying the following conditions is prepared,

[0015] including a cylinder and a screw disposed inside the cylinder,

[0016] the cylinder has at least one devolatilization aid supply port and at least one devolatilization port for discharging volatile components as an opening portion, and has at least one configuration portion in which the devolatilization aid supply port and the devolatilization port are arranged at intervals from an upstream side,

[0017] the screw has at least one screw structure in which a seal ring is disposed at a supply port upstream portion located upstream of the position of the devolatilization aid supply port provided with the at least one configuration portion in the cylinder and a supply port downstream portion located between the devolatilization aid supply port and the devolatilization port of the configuration portion, and

[0018] in a region between the supply port upstream portion and the supply port downstream portion in which the seal ring is disposed, no opening portion that communicates the region and the outside of the cylinder is provided other than the devolatilization aid supply port that serves as a reference for the positions of the supply port upstream portion and the supply port downstream portion,

[0019] In the manufacturing of the resin composition, when the raw material of the resin composition fed into the cylinder is conveyed from the upstream side to the downstream side while being kneaded by the screw of the mixing extruder,

[0020] The filling rate of the raw material in at least one region between the upstream portion of the feeding port and the downstream portion of the feeding port in the cylinder in which the seal ring is provided is set to 70% or more, and a devolatilization aid is supplied from the devolatilization aid feeding port to the raw material in the cylinder and a volatile component contained in the raw material is discharged from the devolatilization port.

[0021] That is, the present application provides the following solutions.

[0022] [1] A manufacturing method of a resin composition, wherein

[0023] The manufacturing method of the resin composition includes:

[0024] A mixing extruder preparation step in which a mixing extruder is prepared,

[0025] The mixing extruder includes a cylinder and a screw provided in the cylinder,

[0026] The cylinder has at least one devolatilization aid feeding port and at least one devolatilization port for discharging a volatile component as an opening portion, and has at least one configuration portion in which the devolatilization aid feeding port and the devolatilization port are arranged at intervals from the upstream side,

[0027] The screw has at least one screw structure in which a seal ring is provided in a feeding port upstream portion located on the upstream side of a position of the devolatilization aid feeding port provided with at least one configuration portion in the cylinder and a feeding port downstream portion located between the devolatilization aid feeding port and the devolatilization port of the configuration portion, and

[0028] In the region between the feeding port upstream portion and the feeding port downstream portion in which the seal ring is provided, no opening portion that communicates the region with the outside of the cylinder is provided except for the devolatilization aid feeding port that is a reference for the positions of the feeding port upstream portion and the feeding port downstream portion; and

[0029] A conveying kneading step in which the raw material of the resin composition fed into the cylinder is conveyed from the upstream side to the downstream side while being kneaded by the screw of the mixing extruder,

[0030] In the conveyance kneading step, the filling rate of the raw material in at least one region of the region of the cylinder in which the upstream portion of the supply port and the downstream portion of the supply port are disposed with the seal ring interposed therebetween is set to 70% or more, the devolatilization aid is supplied from the devolatilization aid supply port to the raw material in the cylinder, and the volatile component contained in the raw material is discharged from the devolatilization port, thereby obtaining a resin composition.

[0031] [2] The resin composition production method according to [1], wherein, in the conveyance kneading step, the filling rate of the raw material in the region of the cylinder in which the upstream portion of the supply port and the downstream portion of the supply port are disposed with the seal ring interposed therebetween is set to 80% or more.

[0032] [3] The resin composition production method according to [1] or [2], wherein the devolatilization aid is water.

[0033] [4] A resin composition production apparatus, wherein

[0034] The resin composition production apparatus is composed of a kneading extruder including:

[0035] a cylinder;

[0036] a screw disposed in the cylinder;

[0037] a screw driving device for driving the screw;

[0038] a raw material supply device for supplying a raw material to the cylinder;

[0039] a devolatilization aid supply device for supplying a devolatilization aid to the cylinder;

[0040] a temperature adjusting device for adjusting the temperature of the cylinder; and

[0041] a control device electrically connected to the screw driving device, the raw material supply device, the devolatilization aid supply device, and the temperature adjusting device, and for controlling the operation of each device,

[0042] the cylinder has at least one devolatilization aid supply port and at least one devolatilization port for discharging a volatile component as an opening portion, and has at least one configuration portion in which the devolatilization aid supply port and the devolatilization port are arranged at intervals in order from the upstream side,

[0043] the screw has at least one screw structure provided with a seal ring at a portion of the screw upstream of the devolatilization aid supply port and at a portion of the screw between the devolatilization aid supply port and the devolatilization port of the at least one structure portion provided at a position upstream of the position of the devolatilization aid supply port,

[0044] the mixing extruder satisfies the following condition: in a region between the portion of the screw upstream of the devolatilization aid supply port and the portion of the screw downstream of the devolatilization aid supply port, no opening portion is provided that communicates the region with the outside of the barrel, except for the devolatilization aid supply port that is a reference for the positions of the portion of the screw upstream of the devolatilization aid supply port and the portion of the screw downstream of the devolatilization aid supply port,

[0045] the mixing extruder is a device used to manufacture a resin composition by mixing while conveying a raw material of a resin composition supplied into the barrel from the upstream side to the downstream side using the screw,

[0046] the control device controls the operation of the screw drive device, the raw material supply device, the devolatilization aid supply device, and the temperature adjustment device in such a manner that, when mixing is performed while conveying the raw material from the upstream side to the downstream side when manufacturing a resin composition, the fill factor of the raw material in at least one region of the region between the portion of the screw upstream of the devolatilization aid supply port and the portion of the screw downstream of the devolatilization aid supply port in the barrel is set to 70% or more, and the raw material in the barrel is supplied with a devolatilization aid from the devolatilization aid supply port and a volatile component included in the raw material is discharged from the devolatilization port.

[0047] [5] The device for manufacturing a resin composition according to [4], wherein

[0048] the mixing extruder further includes a pressure reduction device connected to the devolatilization port,

[0049] the control device is further electrically connected to the pressure reduction device, and

[0050] the control device controls the operation of the screw drive device, the raw material supply device, the devolatilization aid supply device, and the temperature adjustment device and controls the operation of the pressure reduction device when manufacturing a resin composition.

[0051] Further, the reason why the above object is achieved by the resin composition production method of the present application and the resin composition production apparatus of the present application is not necessarily determined, but the present inventors and others have conjectured as follows. That is, first, the present inventors and others have repeatedly conducted intensive studies on the technology described in Patent Literature 1 and Non-Patent Literature 1, and as a result, it has been considered that in the technology described in Patent Literature 1, the pressure in the cylinder cannot be sufficiently increased at the time of kneading the raw material to which the devolatilization aid is added, and therefore from the stage before devolatilization using a vacuum pump (reduction pump) from the devolatilization discharge port, the devolatilization aid in the raw material becomes in a gaseous state, resulting in failure to sufficiently disperse the liquid devolatilization aid into the raw material, and failure to sufficiently remove the volatile organic compounds. Further, the present inventors and others have considered that in the case of using the kneading extruder described in Non-Patent Literature 1, depending on the use conditions (for example, the feeding speed of the raw material into the cylinder, etc.) of the kneading extruder, the pressure in the cylinder at the time of kneading after adding the devolatilization aid cannot necessarily be sufficiently increased, and therefore the volatile organic compounds cannot necessarily be sufficiently removed. In this way, the present inventors and others have repeatedly conducted intensive studies, and as a result, it has been considered that in the conventional resin composition production method described in Patent Literature 1 and Non-Patent Literature 1, there is a problem in the pressure in the cylinder at the time of kneading after adding the devolatilization aid. Further, in view of such a problem, in the present application, the filling rate of the raw material in at least one of the regions (regions sandwiched by the two sealing rings: regions in which the raw material containing the devolatilization aid is kneaded after adding the devolatilization aid) of the cylinder upstream of the supply port and downstream of the supply port in which the sealing ring is disposed is set to 70% or more using the specific kneading extruder of the present application described above. Thereby, at the time of supplying the devolatilization aid from the devolatilization aid supply port to the raw material in the cylinder, the pressure in this region of the cylinder is kept sufficiently high regardless of the feeding speed of the raw material into the cylinder of the kneading extruder, and the problem of volatilization of the devolatilization aid due to low pressure in this region is sufficiently suppressed. Therefore, the present inventors and others have conjectured that at the time of kneading the raw material and the devolatilization aid, it is possible to knead the liquid devolatilization aid and the raw material under high pressure conditions, it is possible to sufficiently maintain the liquid state of the devolatilization aid and more sufficiently disperse and more uniformly distribute the devolatilization aid into the raw material (raw material of the molten resin composition), and at the time of devolatilizing the volatile components (volatile gases such as volatile organic compounds and devolatilization aid) from the devolatilization port of the region located further downstream than the sealing ring of the downstream of the supply port, it is possible to more efficiently discharge (devolatilize) the volatile organic compounds at a higher level, and thereby it is possible to efficiently produce a resin composition in which the residual amount of volatile organic compounds is sufficiently low.

[0052] Effects of the Invention

[0053] According to the present application, it is possible to provide a resin composition production method capable of efficiently producing a resin composition having a sufficiently low residual amount of a volatile organic compound and a resin composition production apparatus capable of being appropriately used for the method. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 is a schematic cross-sectional view schematically showing a cross section of a preferred one embodiment of a mixing extruder that can be used in the resin composition production method of the present application.

[0055] Figure 2 is a schematic cross-sectional view schematically showing a cross section of another preferred one embodiment of a mixing extruder that can be used in the resin composition production method of the present application.

[0056] Figure 3 is a schematic cross-sectional view schematically showing a cross section of still another preferred one embodiment of a mixing extruder that can be used in the resin composition production method of the present application.

[0057] Figure 4 is a schematic cross-sectional view schematically showing a cross section of a preferred one embodiment of a resin composition production apparatus of the present application.

[0058] Figure 5 is a flowchart showing an example of a preferred procedure for finding a required operation condition using a mixing simulation software (TEX-FAN manufactured by Nippon Steel & Sumikin Engineering Co., Ltd.).

[0059] Figure 6 is a schematic cross-sectional view schematically showing a cross section of a mixing extruder used in Comparative Examples 1 and 2. DETAILED DESCRIPTION

[0060] Hereinafter, a preferred embodiment of the present application will be described in detail with reference to the accompanying drawings. In addition, in the following description and drawings, the same or corresponding elements are denoted by the same reference numerals, and repetitive description will be omitted.

[0061] [Preferred Embodiment of the Resin Composition Production Method of the Present Invention]

[0062] (First Embodiment)

[0063] <Mixing Extruder Preparation Step>

[0064] In the present application, a mixing extruder is prepared in the mixing extruder preparation step. Figure 1This is a schematic cross-sectional view illustrating a preferred embodiment of the compounding extruder of the present invention. Furthermore, in this specification, when describing the positional relationships of various structures (screw elements, etc.), the conveying direction (flow direction) of the raw material (including the melt compound) of the resin composition is expressed using terms such as "upstream" and "downstream" or "upstream side" and "downstream side".

[0065] Figure 1 The compounding extruder shown in the embodiment is a twin-screw compounding extruder (screw-type compounding devouring extruder) comprising a barrel 1, a screw 2 disposed within the barrel 1, and a hopper 3 connected to the upstream portion of the barrel 1 for supplying raw materials. Figure 1 For simplicity, only the screw on one shaft side is depicted in the diagram. Furthermore, screw 2 is connected to a rotary drive mechanism (not shown), allowing it to rotate freely inside the barrel 1. Figure 1 The compounding extruder shown is designed such that the downstream end of the barrel 1 is connected to a die (not shown), from which the molten compounded resin composition is extruded (discharged) during use, resulting in a resin composition that allows VOCs to be de-volatile. Furthermore, in Figure 1 The compounding extruder shown in the figure is designed such that a heater (not shown) is provided on the outside of the entire area of ​​the barrel 1, thereby heating the barrel to a heating temperature (set temperature) appropriately set according to the type of raw material, so that the raw material is melted and compounded.

[0066] Additionally, the barrel 1 is provided with devolatilization aid supply ports (DA supply ports) 11A and 11B for supplying devolatilization aid DA, and devolatilization ports (exhaust ports) 12A and 12B for discharging devolatilized VOCs as openings. Furthermore, these DA supply ports 11A and 11B are respectively connected to a devolatilization aid DA supply device (e.g., a water injection device if the devolatilization aid DA is water) (not shown). Additionally, devolatilization ports 12A and 12B are respectively connected to a pressure reducing device (vacuum pump) (not shown). Figure 1 In order to supply raw materials (raw materials of resin composition) from hopper 3, barrel 1 is also provided with an opening (raw material supply port) 13 for supplying raw materials.

[0067] Thus, in the cylinder 1, as the opening portions, two DA supply ports 11A and 11B, two devolatilization ports (discharge ports) 12A and 12B, and a raw material supply port 13 are provided. In addition, from the arrangement relationship of the two DA supply ports and the two devolatilization ports, the cylinder 1 has a configuration portion in which the DA supply port 11A and the devolatilization port 12A are arranged at intervals from the upstream side toward the downstream side, and a configuration portion in which the DA supply port 11B and the devolatilization port 12B are arranged at intervals from the upstream side toward the downstream side in a region on the more downstream side of the configuration portion. By having such configuration portions, after the devolatilization aid DA introduced from the DA supply port and the raw material are kneaded in each configuration portion, the kneaded product can be transported to the region in which the devolatilization port is provided to be devolatilized, and in combination with the screw structure and the like described later, the volatile organic compound VOC as the volatile component can be more efficiently discharged (devolatilized) from the devolatilization port.

[0068] Further, from the viewpoint of being able to more efficiently remove the VOC, the ratio of the length to the diameter (length / diameter) of the cylinder 1 is preferably 21 to 106. In addition, from the viewpoint of being able to more sufficiently suppress heat generation in the kneading even when the raw material is in a pellet form and the kneading of the pellets does not particularly cause a problem, the diameter of the cylinder 1 is preferably 12 to 90 mm.

[0069] In addition, the screw 2 is formed by mounting various screw elements (screw sections: screw segments) on a shaft. Furthermore, the screw 2 has a screw structure in which a full flight screw FS, a kneading disc KD (a KD1 in which a kneading wing is provided in a Figure 1 disclosed arrangement configuration of the full flight screw FS, the kneading disc KD (a KD1 in which a kneading wing is provided in a Figure 1 disclosed arrangement configuration of the full flight screw FS, the kneading disc KD (a KD1 in which a kneading wing is provided in a 1～3 seal ring SR (a SR1 in which a seal wing is provided in a Figure 1 disclosed arrangement configuration of the full flight screw FS, the kneading disc KD (a KD1 in which a kneading wing is provided in a 1～4 seal ring SR (a SR1 in which a seal wing is provided in a

[0070] Regarding the structure of the screw 2, if we explain the positional relationship of the parts where the sealing rings are arranged in the order of sealing ring SR1, kneading disc KD2, and sealing ring SR2 in the screw structure based on the positions of the DA supply port 11A and the devolatilization port 12A of the barrel 1, then the sealing ring SR1 is positioned upstream of the location where the DA supply port 11A is located (upstream of the upstream end of the DA supply port 11A). Furthermore, the sealing ring SR2 is positioned downstream of the location where the DA supply port 11A is located (downstream of the downstream end of the DA supply port 11A) and is located between the DA supply port 11A and the devolatilization port 12A. That is, when studying the positional relationship of the sealing ring SR in the structural part of the barrel 1 where the DA supply port 11A and the devolatilization port 12A are arranged, the screw 2 has a screw structure in which the sealing ring SR1 is arranged upstream of the position where the DA supply port 11A is located (the part of the barrel 1 in which the sealing ring SR1 is arranged upstream of the DA supply port 11A is called the "upstream supply port part") and the sealing ring SR2 is arranged between the DA supply port 11A and the devolatilization port 12A (the part of the barrel 1 in which the sealing ring SR2 is arranged downstream of the DA supply port 11A is called the "downstream supply port part"). On the other hand, in region A1 between the upstream portion of the supply port (the portion where a sealing ring is disposed upstream of the base devolatilization aid supply port) and the downstream portion of the supply port (the portion where a sealing ring is disposed downstream of the base devolatilization aid supply port), no opening is provided to connect region A1 to the outside of the barrel 1, except for the DA supply port 11A (an opening that serves as a reference for the positions of the upstream and downstream portions of the supply port). Furthermore, the "region A1" referred to here, based on the DA supply port 11A, refers to the area within the barrel enclosed by a plane containing the downstream end face of the sealing ring SR1 that is perpendicular to the barrel axis (a plane containing the upstream end of the kneading disc KD2 that is perpendicular to the barrel axis) and a plane containing the upstream end face of the sealing ring SR2 that is perpendicular to the barrel axis (a plane containing the downstream end of the kneading disc KD2 that is perpendicular to the barrel axis). Thus, in this specification, "the area within the barrel between the upstream portion of the supply port and the downstream portion of the supply port where the sealing ring is disposed" refers to the area within the barrel sandwiched between a plane containing the downstream end face of the sealing ring (upstream side sealing ring) disposed in the upstream portion of the supply port, which is perpendicular to the axis of the barrel, and a plane containing the upstream end face of the sealing ring disposed in the downstream portion of the supply port, which is perpendicular to the axis of the barrel. Furthermore, when considering the sealing ring SR based on the structural configuration of the DA supply port 11B and the devouring port 12B of the barrel 1... 3～4In the present embodiment, when the DA supply port 11B is provided at a position in the screw structure where the seal ring SR3 and the seal ring SR4 are provided in the screw structure, the seal ring SR3 and the seal ring SR4 are provided in the screw structure in the upstream portion of the supply port (a portion on the upstream side of the DA supply port 11B) and in the downstream portion of the supply port (a portion on the downstream side of the DA supply port 11B) on the upstream side of the position at which the DA supply port 11B is provided, respectively. In addition, in the case of the seal rings SR3 and SR4, the seal ring SR3 and the seal ring SR4 are provided in the screw structure in the upstream portion of the supply port (a portion on the upstream side of the DA supply port 11B) and in the downstream portion of the supply port (a portion on the downstream side of the DA supply port 11B) on the upstream side of the position at which the DA supply port 11B is provided, respectively. 3～4 In the region A2 between the upstream portion of the supply port and the downstream portion of the supply port in the cylinder 1 in the case of the seal rings SR3 and SR4, as well, no opening portion other than the DA supply port 11B (an opening portion serving as a reference for the position of the upstream portion of the supply port and the downstream portion of the supply port) is provided. Thus, in the case of the seal rings SR3 and SR4, as well, the seal rings SR3 and SR4 are provided in the screw structure in the upstream portion of the supply port (a portion on the upstream side of the DA supply port 11B) and in the downstream portion of the supply port (a portion on the downstream side of the DA supply port 11B) on the upstream side of the position at which the DA supply port 11B is provided, respectively. Figure 1 In the kneading extruder of the embodiment shown in FIG. 1, the regions Al and A2 are regions in which kneading is performed with the addition (supply) of the devolatilization aid DA (preferably water). Thus, hereinafter, for convenience, the regions (Al, A2) between the upstream portion of the supply port and the downstream portion of the supply port in the cylinder in which the seal rings are provided in the regions in which kneading is performed with the addition (supply) of the devolatilization aid DA will be referred to simply as "DA addition kneading regions" depending on the case.

[0071] In addition, the diameter D of the screw 2 is not particularly limited, but is preferably 80 to 99.5% of the diameter of the cylinder 1. In the case where the ratio of the diameter D of the screw 2 to the diameter of the cylinder 1 is the lower limit or more, compared to the case where it is less than the lower limit, there is a tendency that the resin composition can be kneaded more sufficiently, and on the other hand, in the case where it is the upper limit or less, compared to the case where it exceeds the upper limit, it is more difficult to cause interference between the screw and the cylinder in terms of structure (interference does not occur substantially), and thus there is a tendency that more stable processing can be performed.

[0072] As such a screw 2, there is no particular limitation, but in the case where the length (total length) of the screw is L and the diameter (outer diameter) of the screw is D, the value of L / D of the screw is preferably 20 to 105, more preferably 25 to 100. In the case where the value of L / D is the lower limit or more, compared to the case where it is less than the lower limit, there is a tendency that the resin composition can be kneaded more sufficiently, and on the other hand, in the case where it is the upper limit or less, compared to the case where it exceeds the upper limit, there is a tendency that excessive rise in kneading torque can be suppressed, and more stable processing can be performed. Note that the "length of the screw" referred to here means the total length of the portion in which the screw element is provided, that is, the total length in the conveying direction of the portion in which the screw functions as a screw formed by combining a plurality of elements.

[0073] Further, in the screw 2, the ratio of the length (L1) of the range sandwiched by the downstream end of the seal ring SR1 and the upstream end of the seal ring SR2 of the screw to the diameter D of the screw (L1 / D) is preferably 2 or more (more preferably 5 to 50). Further, the ratio of the length (L2) of the range sandwiched by the downstream end of the seal ring SR3 and the upstream end of the seal ring SR4 to the diameter D of the screw (L2 / D) is also preferably 2 or more (more preferably 2 to 50). In this way, with one DA feeding port (11A or 11B) as a reference, the ratio of the length (L1 or L2) of the range sandwiched by the downstream end of the seal ring (SR1 or SR3) located in the upstream portion of the feeding port and the upstream end of the seal ring (SR2 or SR4) located in the downstream portion of the feeding port to the diameter D of the screw (L1 / D or L2 / D) is preferably 2 or more (more preferably 2 to 50). When the value of such L1 / D or L2 / D is less than the lower limit, there is a tendency for the kneading of the devolatilization aid and the resin composition to become insufficient. Further, in the case where the value of L1 / D is the upper limit or less, there is a tendency for the processing to be more stable, and for the excessive rise in the kneading torque to be able to be suppressed further, compared to the case where the upper limit is exceeded. I or L2) with the diameter D of the screw (L I / D or L2 / D) is preferably 2 or more (more preferably 2 to 50). When the value of such L I / D or L2 / D is less than the lower limit, there is a tendency for the kneading of the devolatilization aid and the resin composition to become insufficient. Further, in the case where the value of L I / D is the upper limit or less, there is a tendency for the processing to be more stable, and for the excessive rise in the kneading torque to be able to be suppressed further, compared to the case where the upper limit is exceeded.

[0074] Further, in such a screw 2, the length (distance in the conveying direction) of the region in which the kneading disc KD1 is disposed (the region in which the raw material is initially kneaded) can be appropriately designed according to the kind of the raw material or the like, and is not particularly limited, but in order to be able to reliably supply the raw material in a molten state to the region A1 (DA addition kneading region), it is preferably set to a length of 1 to 30 times (more preferably 2 to 25 times) the diameter D of the screw.

[0075] Further, in the kneader-extruder of the above-described embodiment, the raw material (molten kneaded material) conveyed to the downstream side through the portion of the devolatilization port 12A is blocked by the seal ring SR3 disposed at a position further downstream than the devolatilization port 12A, and the conveying speed becomes slow, but depending on the positional relationship between the devolatilization port 12A and the seal ring SR3, the raw material supply speed, the screw rotation speed, or the like, there is a possibility that a problem of outflow from the devolatilization port 12A to the outside of the cylinder 1 will occur, and therefore the distance from the downstream end of the devolatilization port 12A to the upstream end of the seal ring SR3 is desirably appropriately set to a length such that the molten kneaded material does not flow out from the devolatilization port 12A in the operation of the kneader, and the distance in the conveying direction between the devolatilization port and the seal ring further downstream than the devolatilization port (for example, the distance between the position of the downstream end of the devolatilization port 12A and the position of the upstream end of the seal ring SR3) is preferably 1 to 30 times (more preferably 3 to 25 times) the diameter D of the screw.

[0076] Further, in the screw 2, the length (distance in the conveying direction) between the downstream end of the seal ring SR2 and the upstream end of the seal ring SR3 is preferably 2 to 30 times (more preferably 4 to 25 times) the diameter D of the screw, from the viewpoint of the removal rate of the volatile components.

[0077] Further, in the screw 2, the length (distance in the conveying direction) between the downstream end of the seal ring SR2 and the upstream end of the seal ring SR3 is preferably 2 to 30 times (more preferably 4 to 25 times) the diameter D of the screw, from the viewpoint of the removal rate of the volatile components.

[0078] Further, the hopper 3, the mold, and other structures are not particularly limited, and a publicly known structure can be appropriately used, and can be appropriately disposed in a manner capable of functioning as intended.

[0079] In the above, in the description Figure 1 In the kneader-extruder of the embodiment shown in the drawing, as the barrel 1, a barrel having two devolatilization aid supply ports (11A, 11B) and two devolatilization ports (12A, 12B) for discharging volatile components as opening portions, and having two configuration portions in which the devolatilization aid supply ports and the devolatilization ports are arranged at intervals from the upstream side, is used, and as the screw 1, a screw having two screw structures in which seal rings are respectively arranged at a supply port upstream portion located at a position upstream of a position at which the devolatilization aid supply port is provided and at a supply port downstream portion located between the devolatilization aid supply port and the devolatilization port in the barrel, is used, in consideration of the screw structure with the positions of the devolatilization aid supply ports and the devolatilization ports in the respective configuration portions as references.

[0080] Such a barrel 1 is used, and a screw having a seal ring SR 1～4The screw 2 is configured so that the position of the DA supply port is set to the above-mentioned position, and the filling rate of the raw material in at least one of the regions (region Al and / or region A2) in which the DA additive can be introduced through the DA supply port and which are regions sandwiched by the seal rings SR in the cylinder 1 (DA additive mixing region: regions Al and A2) is set to 70% (vol%) or more, so that the raw material and the DA additive can be mixed under high pressure conditions in the region, and the DA additive DA can be highly inhibited from becoming a gaseous state (volatilized state) in the region at the time of mixing, and thus the DA additive DA and the raw material of the resin composition, which sufficiently maintain a liquid state, can be mixed in the region, the DA additive DA can be more sufficiently dispersed into the raw material and more uniformly distributed when mixed in the region, and the volatile organic compounds VOC can be more efficiently devolatilized at a higher level at the devolatilization port of the region located further downstream than the seal ring (downstream seal ring) disposed in the downstream portion of the supply port.

[0081] <Conveying and mixing process>

[0082] In the first embodiment, after the above-mentioned Figure 1 The conveying and mixing process is performed using the mixing extruder.

[0083] In the case where the conveying and mixing process is performed using the mixing extruder of the embodiment illustrated in Figure 1 In the case where the conveying and mixing process is performed using the mixing extruder of the embodiment illustrated in Figure 1The molten material is conveyed in the indicated direction of conveyance to a region in which kneading disks KD1 are provided, and initial melt-kneading of the raw material is performed in the region in which the kneading disks KD1 are provided. Subsequently, the melt-kneaded raw material (melt-kneaded material) is conveyed by the full-flight screw SF on the downstream side of the kneading disks KD1 to a position in which the seal ring SR1 is provided (a portion upstream of the supply port of the DA supply port 11A), and then, after passing through the position in which the seal ring SR1 is provided, is conveyed into the region Al (a region in which the kneading disks KD2 are provided: first DA-addition kneading region). The melt-kneaded material is kneaded by the kneading disks KD2. When kneading is performed in such a region Al, the devolatilization aid DA (preferably water) is added from the DA supply port 11A, and the molten raw material and the liquid devolatilization aid DA are kneaded. Then, when the melt-kneaded material (molten raw material) to which the liquid devolatilization aid DA has been added is conveyed to a position on the downstream side of the region Al in which the seal ring SR2 is provided (a portion downstream of the supply port), the molten raw material is further conveyed toward the downstream side by the full-flight screw SF provided on the downstream side of the seal ring SR2. At this time, by the operation of a vacuum pump (not shown) connected to the devolatilization port 12A, the pressure in the vicinity of the devolatilization port (discharge port) 12A (discharge portion) can be made low (preferably 1 to 100 kPa or so), and thus the devolatilization aid DA can be vaporized from the melt-kneaded material present in the vicinity of the devolatilization port 12A, and a volatile organic compound can also be volatilized, and these volatilized components can be discharged from the devolatilization port 12A. Furthermore, by the use of the devolatilization aid, in the discharge portion, the devolatilization aid in the raw material vaporizes and expands, and the surface area of the raw material increases, and thus the effect of volatilized components inside being removed by volatilization from the high-temperature surface of the raw material is improved, and thus the volatile organic compound can be more efficiently volatilized during devolatilization. Then, the raw material after devolatilization is conveyed to a region in which the seal ring SR3 is provided, and then, after passing through the region in which the seal ring SR3 is provided, is conveyed into the region A2 (a region in which the kneading disks KD3 are provided: second DA-addition kneading region), and is kneaded by the kneading disks KD3. Furthermore, in the region A2, the devolatilization aid DA (preferably water) is added from the DA supply port 11B, and the molten raw material and the devolatilization aid DA are kneaded. Subsequently, when the melt-kneaded material (molten raw material) to which the devolatilization aid DA has been added is conveyed to a region on the downstream side of the region A2 in which the seal ring SR4 is provided, the melt-kneaded material is further conveyed toward the downstream side by the full-flight screw SF provided on the downstream side of the seal ring SR4. Furthermore, by such conveyance, when passing through a position in which the devolatilization port 12B is provided, by the operation of a vacuum pump (not shown) connected to the devolatilization port 12B, the pressure in the vicinity of the devolatilization port 12B can be made low, and thus the devolatilization aid and the volatile organic compound can be volatilized from the raw material present in the vicinity of the devolatilization port 12B, and can be discharged from the devolatilization port 12B.Thus, after devolatilization of the volatile components (including volatile organic compounds), the devolatilized melt-kneaded material is directly delivered to the outlet of the cylinder. Thus, after kneading is performed while the raw material is delivered from the upstream side to the downstream side in the cylinder, the raw material is delivered to the outlet of the cylinder, and is extruded to the outside from a mold (omitted illustration) connected to the outlet portion thereof, and a resin composition can be obtained. Thus, by using the kneading extruder and operating it, a resin composition can be obtained by using the screw 2 to perform kneading while the raw material of the resin composition fed into the cylinder 1 is delivered from the upstream side to the downstream side.

[0084] In such a process, as the raw material of the resin composition to be fed into the cylinder, there is no particular limitation, but at least one resin can be included. As such a resin, a thermoplastic resin is preferable, and for example, a polyolefin-based resin (polyethylene, polypropylene, etc.), a polyamide-based resin, a polyester-based resin, a polycarbonate-based resin, an acrylic-based resin, a styrene-based resin, a vinyl chloride-based resin, a polyphenylene sulfide, a polyphenylene ether, a thermoplastic elastomer, and the like can be mentioned. Furthermore, the resin included in the resin composition can be used alone, or two or more kinds can be combined. In addition, as the raw material of such a resin composition, in order to recycle the resin composition, a resin composition taken out from a discarded product can be used. In addition, in the resin composition, components other than the resin are not particularly limited, and various fillers, pigments, and the like, which are well known, can be appropriately used in accordance with the design of the resin composition as a target. Furthermore, as the raw material, a raw material in a form formed of a single resin not including components such as fillers can be used as a resin composition (for the reason that even a single resin not including fillers can be recognized as a composition of a resin including volatile organic compounds (volatile low-molecular-weight organic substances) as impurities). Furthermore, the form of the raw material of such a resin composition is not particularly limited, but from the viewpoint of making it easier to perform melt-kneading, a raw material in a granular or powder form (powdered form) is preferable.

[0085] In addition, as the devolatilization aid DA, there is no particular limitation, and well-known components such as water, alcohol, lower aliphatic hydrocarbons, and the like can be appropriately used, but from the viewpoint of making the work safety higher, water is more preferable. In addition, in the case where water is used as the devolatilization aid DA, an additive can also be included in the water.

[0086] Furthermore, in the conveying and mixing process, the filling rate of the raw material needs to be set to 70% or more (more preferably 80% or more, and even more preferably 85 to 100%) in at least one area (at least one of the areas if multiple DA addition mixing areas exist, and on the other hand, if the DA addition mixing area exists only in one place in the barrel) within the barrel. When the filling rate of such raw material is less than the lower limit, the residual amount of volatile organic compounds cannot be sufficiently reduced, and the desired resin composition cannot be obtained. In addition, in this invention, the "filling rate of raw material" is the value of the filling ratio (filling rate: volume%) of the raw material relative to the total volume (the total volume of the space excluding the screw volume) of the DA addition mixing area, which is obtained by analysis using mixing simulation software (manufactured by Nippon Steel, trade name: TEX-FAN). Furthermore, such a filling rate can be adjusted by controlling the operation (including the feed rate of raw materials, etc.) according to the design of the compounding extruder. In addition, in this invention, it is sufficient for the filling rate of the raw material in at least one of the DA addition compounding zones within the barrel to be 70% or more; however, from the perspective of being able to remove (reduce) volatile organic compound residues to a higher level, it is more preferable to have the raw material filling rate in all DA addition compounding zones present within the barrel (in... Figure 1 In one implementation, the filling rate of the raw material in regions A1 and A2 is set to 70% or more.

[0087] Furthermore, in the conveying and mixing process, it is preferable to control the operation of the mixing extruder (including the amount of raw material input, etc.) according to the design of the mixing extruder, so that in the DA addition mixing zone, where the raw material filling rate is 70% or more, the residence time of the raw material (melt mix) of the resin composition flowing into the zone is 10 seconds or more (more preferably 20 seconds or more, and even more preferably 30 seconds or more and 600 seconds or less). By making the residence time of the raw material in the DA addition mixing zone within this range, VOCs can be removed more efficiently while suppressing the thermal decomposition of the resin composition. In addition, such a residence time (the residence time of the raw material from the time it flows into the zone until it flows out) is a value obtained by analysis using mixing simulation software (manufactured by Nippon Steel, trade name: TEX-FAN).

[0088] Further, in the conveyance kneading step, the internal pressure of the raw material (molten resin composition) in the cylinder in the DA-addition kneading zone is preferably made higher than the vapor pressure of the devolatilization aid at the temperature of the DA-addition kneading zone. For example, in the case where the devolatilization aid is water and the heating temperature is 170°C, the saturated vapor pressure of water is 0.792 MPa, and thus the pressure is preferably made higher than this. In this way, by making the internal pressure of the resin composition in the DA-addition kneading zone higher than the vapor pressure of the devolatilization aid and supplying (injecting) the devolatilization aid, the devolatilization of the devolatilization aid is sufficiently suppressed to easily maintain the liquid state, and thus a sufficient amount of the liquid devolatilization aid can be dispersed in the resin composition to perform kneading.

[0089] Further, the amount of the devolatilization aid added to the raw material (molten resin composition) present in the DA-addition kneading zone is appropriately adjusted according to the kind of the raw material and the like, and is not particularly limited, but from the viewpoint of being able to more efficiently remove VOCs while suppressing excessive increase in the kneading torque, it is preferably 0.01 to 20 parts by mass (more preferably 0.01 to 15 parts by mass, further preferably 0.01 to 0.5 parts by mass, particularly preferably 0.02 to 0.3 parts by mass) relative to 100 parts by mass of the raw material in the DA-addition kneading zone.

[0090] Further, in the conveyance kneading step, the supply speed of the raw material of the resin composition into the cylinder is not particularly limited, but is preferably 1 to 1000 kg / h (more preferably 2 to 800 kg / h). In the case where the supply speed of the raw material is the lower limit or more, there is a tendency to be able to obtain a higher effect in terms of improvement in the processing speed compared to the case where it is less than the lower limit, and on the other hand, in the case where it is the upper limit or less, there is a tendency to be able to obtain a higher effect in terms of improvement in the removal rate of VOCs compared to the case where it exceeds the upper limit.

[0091] In this way, in the case where the resin composition is kneaded using the kneading extruder of the embodiment shown in FIG. 1 and the resin composition is conveyed from the upstream side to the downstream side in the cylinder 1 while being kneaded by the screw 2, by making the filling rate of the raw material of the resin composition in at least one of the regions A1 and A2 in the DA-addition kneading zone (the region between the upstream portion of the supply port and the downstream portion of the supply port in the cylinder in which the seal ring SR is disposed: Figure 1 Figure 1 and supplying the devolatilization aid DA from the devolatilization aid supply port (11A, 11B) to the raw material in the cylinder 1 and discharging the volatile components contained in the raw material from the devolatilization port (12A, 12B), a resin composition from which volatile organic compounds are sufficiently devolatilized at a sufficiently high level can be obtained.

[0092] ​The above is based on Figure 2 Preferred embodiments of the method for manufacturing the resin composition of the present invention have been described, but the method for manufacturing the resin composition of the present invention is not limited to the above embodiments. Hereinafter, based on... Figure 3 and Figure 2 Another preferred embodiment of the method for manufacturing the resin composition of the present invention will be described.

[0093] (Second Implementation)

[0094] In the second embodiment, in the preparation step of the compounding extruder, in addition to preparing Figure 2 Apart from the compounding extruder shown, the same process as in the first embodiment can be used to obtain the desired resin composition.

[0095] Figure 1 The compounding extruder of the illustrated embodiment is essentially the same as the one shown, except for the length (distance in the conveying direction) L3 between the upstream end of the sealing ring SR1 and the downstream end of the raw material supply port, the positional relationship of the two DA supply ports 11A and 11B, the two devouring ports (discharge ports) 12A and 12B, and the screw structure in regions A1 and A2 (DA addition compounding regions) which is a combination of a kneading disc KD and a threaded screw. Figure 2 The mixing extruder shown in the embodiment is the same. Furthermore, in Figure 2 In the embodiment shown, the screw structure is arranged from the upstream side to the downstream side in the order of FS, KD1, FS, SR1, KD2, FS, KD2, SR2, FS, SR3, KD3, FS, KD3, SR4, FS.

[0096] Here, in Figure 1 In the compounding extruder of the embodiment shown, with Figure 2 Compared to the embodiment shown, the length between the upstream end of the sealing ring SR1 and the downstream end of the raw material supply port is longer. However, the length (distance in the conveying direction) L3 between the upstream end of the sealing ring SR1 and the downstream end of the raw material supply port falls into the same range as described above (3 to 30 times (more preferably 5 to 25 times) the screw diameter D). As a result, a melt-mixed compound in which the raw material is fully melted can be obtained in the region upstream of region A1. Furthermore, by making the length between the upstream end of the sealing ring SR1 and the downstream end of the raw material supply port longer, it is advantageous to pre-remove VOCs with lower boiling points.

[0097] In addition, Figure 2In the kneader-extruder of the illustrated embodiment, the positional relationship of the arrangement of the two DA supply ports 11A and 11B and the two devolatilization ports (discharge ports) 12A and 12B is changed compared to the first embodiment, and the reason for this is that, in the Figure 1 In the illustrated embodiment, the length between the upstream end of the seal ring SR1 and the downstream end of the raw material supply port is longer compared to the first embodiment. In this way, it is possible to appropriately use a structure in which the two DA supply ports 11A and 11B are arranged at a position at which the supply of devolatilization aid DA can be performed and the two devolatilization ports (discharge ports) 12A and 12B are arranged at a position at which the exhaust (removal) of volatile components can be performed (depending on the various structures used, it is also possible to appropriately change the position at which the DA supply ports 11A and 11B or the devolatilization ports 12A and 12B are arranged in order to obtain a desired function). Figure 2

[0098] In addition, in the Figure 1 In the kneader-extruder of the illustrated embodiment, in the two DA addition kneading zones (zones Al and A2), the screw structure is set to a structure in which a kneading disc KD and a flighted screw FS are combined. Furthermore, in the case of two kneaders in which the size of the L / D of the DA addition kneading zone is the same, a comparison is made between the case in which a kneading disc KD and a flighted screw FS are combined in the screw of the zone and the case in which the zone is composed of only a kneading disc KD, and in the case in which a flighted screw FS is combined, the residence time of the raw material in the DA addition kneading zone becomes shorter, there is a tendency for the fill factor of the raw material in the DA addition kneading zone to decrease, but there is a tendency for the devolatilization aid to be able to spread over a wide range. Therefore, it is also possible to set a structure in which, in the operation of the kneader-extruder, within a range in which the condition of setting the fill factor of the raw material in the DA addition kneading zone to 70% or more can be satisfied, a flighted screw FS is used in the screw structure in the DA addition kneading zone within an appropriate range. Furthermore, in this case as well, it is preferable for the conditions such as the residence time of the raw material to be satisfied in the range in which the fill factor of the raw material in the DA addition kneading zone is 70% or more. Figure 2 The preferred conditions explained in the illustrated embodiment.

[0099] In the case of using such Figure 2 In the case of the kneader-extruder of the illustrated embodiment as well, the conditions (including the preferred conditions thereof) employed in the conveyance kneading process can basically employ the same conditions as the conditions explained in the first embodiment, and in the case of using Figure 3 ​In the process of the kneading extruder of the illustrated embodiment and the use of the screw 2 to knead while conveying the raw material of the resin composition fed into the cylinder 1 from the upstream side to the downstream side, by setting the fill factor of the raw material in at least one of the DA addition kneading zones or both zones to 70% or more, and supplying the devolatilization aid DA from the devolatilization aid supply port (11A, 11B) to the raw material in the cylinder 1 and discharging the volatile components contained in the raw material from the devolatilization port (12A, 12B), a resin composition from which volatile organic compounds are devolatilized at a sufficiently high level can be obtained.

[0100] (Third Embodiment)

[0101] In the third embodiment, in the kneading extruder preparation process, in addition to the preparation Figure 3 The kneading extruder of the illustrated form can basically adopt the same process as the first embodiment, whereby a desired resin composition can be obtained.

[0102] Figure 2 The kneading extruder of the illustrated embodiment is basically the same as the Figure 3 The kneading extruder of the illustrated embodiment is basically the same as the Figure 3 In the kneading extruder of the illustrated embodiment, the devolatilization aid supply port 11B is not provided, so the devolatilization aid DA is not supplied at zone A2, but the raw material (melt-kneaded material) from which volatile components are devolatilized from the devolatilization port 12A is caused to flow into zone A2, and the raw material is kneaded under high temperature and high pressure conditions in zone A2, so that the remaining volatile components can be removed from the raw material after passing through this zone A2 from the devolatilization port 12B.

[0103] Further, in the case of using such Figure 3 In the case of using the kneading extruder of the illustrated embodiment, the conditions (including preferred conditions thereof) adopted in the conveying and kneading process can basically adopt the same conditions as those described in the first embodiment, and in the case of using Figures 1-3 In the process of the kneading extruder of the illustrated embodiment and the use of the screw 2 to knead while conveying the raw material of the resin composition fed into the cylinder 1 from the upstream side to the downstream side, by setting the fill factor of the raw material in at least one of the DA addition kneading zones or both zones to 70% or more, and supplying the devolatilization aid DA from the devolatilization aid supply port (11A, 11B) to the raw material in the cylinder 1 and discharging the volatile components contained in the raw material from the devolatilization port (12A, 12B), a resin composition from which volatile organic compounds are devolatilized at a sufficiently high level can be obtained.

[0104] In the above, based on Figure 3The preferred embodiment of the method for producing the resin composition of the present application is described, but the method for producing the resin composition of the present application is not limited to the above-described embodiment. For example, in the method for producing the resin composition of the above-described embodiment, a mixing extruder provided with two devolatilization ports is used, but in the present application, the mixing extruder can be provided with the following structure, and the number of devolatilization ports can not be two:

[0105] including a cylinder and a screw disposed in the cylinder,

[0106] the cylinder has at least one devolatilization aid supply port and at least one devolatilization port for discharging a volatile component as an opening portion, and has at least one configuration portion in which the devolatilization aid supply port and the devolatilization port are arranged at intervals from the upstream side,

[0107] the screw has at least one screw structure in which a seal ring is disposed at a supply port upstream portion located upstream of the position of the devolatilization aid supply port provided with the at least one configuration portion in the cylinder and a supply port downstream portion located between the devolatilization aid supply port and the devolatilization port of the configuration portion, and

[0108] in a region between the supply port upstream portion and the supply port downstream portion, no opening portion that communicates the region and the outside of the cylinder is provided except for the devolatilization aid supply port that serves as a reference for the positions of the supply port upstream portion and the supply port downstream portion. That is, at least one devolatilization port is provided, and the number thereof can be one or more (two or more) depending on the type of raw material or the like. Similarly, at least one devolatilization aid supply port is provided, and the number thereof is not particularly limited, and can be one or more (two or more).

[0109] In addition, the screw used in the present application has at least one screw structure in which a seal ring is disposed at a supply port upstream portion and a supply port downstream portion with reference to at least one devolatilization aid supply port of a configuration portion in which the devolatilization aid supply port and the devolatilization port are arranged at intervals from the upstream side, and the number of such screw structure portions is not particularly limited, but can be one (in the case of the mixing extruder shown in Figure 1 , it is one), or two or more (in addition, in the case of the mixing extruder shown in Figure 2 , and Figure 4 , it is two).

[0110] [Preferred Embodiment of the Production Apparatus for the Resin Composition of the Present Invention]

[0111] The apparatus for manufacturing the resin composition of the present invention, as described above, can be suitably used in the method for manufacturing the resin composition of the present invention. That is, in the method for manufacturing the resin composition of the present invention, the apparatus for manufacturing the resin composition of the present invention can be suitably used as a compounding extruder prepared in the compounding extruder preparation step.

[0112] Here, the resin composition manufacturing apparatus of the present invention includes a control device for controlling the filling rate of the raw material in at least one region of the area between the upstream portion and the downstream portion of the supply port where the sealing ring is disposed in the barrel during the conveying and mixing process to be 70% or more, and to supply the devolatilization aid to the raw material in the barrel from the devolatilization aid supply port and to discharge the volatile components contained in the raw material from the devolatilization port. By means of the control device, the filling rate of the raw material in at least one region of the area between the upstream portion and the downstream portion of the supply port where the sealing ring is disposed in the barrel is controlled.

[0113] The following is for reference Figure 4 A preferred embodiment of the apparatus for manufacturing the resin composition of the present invention will be described.

[0114] Figure 1 The apparatus for manufacturing the resin composition of the illustrated embodiment is Figure 4 The shown embodiment represents a preferred configuration of the compounding extruder. Additionally, Figure 1 The device shown in the figure and Figure 4 Similarly, it is a twin-shaft compounding extruder, in Figure 1 In, with Figure 4 Similarly, for simplicity, only the screw on one shaft side is depicted.

[0115] Figure 4The apparatus for manufacturing the resin composition shown is a twin-screw compounding extruder, which includes: a barrel 1; a screw 2 disposed within the barrel 1; a hopper 3 disposed at an opening in the barrel 1 for supplying raw materials; a feeder 30 (in this embodiment, a feeder including a screw 30a for supplying raw materials and a motor 30b for driving the screw 30a), which serves as a raw material supply device for supplying raw materials into the barrel 1 via the hopper 3; a motor 4, which serves as a screw drive device (a rotary drive mechanism connected to the screw 2) for driving the screw 2; and a DA supply device 5 (a supply device for the devolatilization aid DA), which is used for... The extruder includes: a devolatilization aid DA supplied to barrel 1; a pressure reducing device (vacuum pump) 6 for discharging devolatilized components from the devolatilization port; a temperature regulating device 7 for regulating the temperature of barrel 1; a thermometer 8 for measuring the temperature of the barrel; a pressure gauge (pressure sensor) 9 for measuring the pressure in the piping connecting the pressure reducing device 6 to the devolatilization port (12A or 12B) of the barrel; and a control device (controller) 10 electrically connected to the motor 30b included in the feeder 30, the motor 4 serving as a screw drive device for driving the screw 2, the DA supply device 5, the pressure reducing device (vacuum pump) 6, the temperature regulating device 7, the thermometer 8, and the pressure gauge 9. Furthermore, this twin-screw compounding extruder is an apparatus used to manufacture resin compositions by compounding the raw material of the resin composition supplied to the barrel from the upstream side to the downstream side using the screw.

[0116] Such Figure 1 The apparatus for manufacturing the resin composition shown is a twin-screw compounding extruder (screw-type compounding devouring extruder) comprising a barrel 1 and a screw 2 disposed within the barrel 1. All conditions concerning the barrel 1 and the screw 2, including the position and type of the opening of the barrel 1 and the structure of the screw 2, are adopted in accordance with the specifications of the manufacturer. Figure 1 The conditions described in the illustrated configuration are the same as those described above (e.g., the conditions of the two DA supply ports 11A and 11B, the two devouring ports (discharge ports) 12A and 12B, the raw material supply port 13, etc., the conditions of regions A1 and A2, the screw structure, etc., of the screw). Figure 1 (The shapes shown are the same). Therefore, descriptions of the barrel 1 and screw 2 (including descriptions of reference numerals in the drawings) are omitted. Furthermore, regarding the hopper 3, it is also possible to use a type that is compatible with... Figure 4 The hopper shown is the same as the hopper described in the diagram.

[0117] Figure 4 The feeder 30 shown is used as a raw material supply device for supplying raw materials into the barrel 1 via the hopper 3, and includes a screw 30a for supplying raw materials (a screw for adjusting the supply speed of the raw materials) and a motor 30b for driving the screw 30a. Furthermore, in Figure 4In the compounding extruder of the illustrated embodiment, the feed rate of the raw material supplied to the barrel can be appropriately controlled by controlling the operation of the motor 30b of such a feeder (raw material supply device) (controlling the speed of the motor 30b). There are no particular limitations on such a feeder; any known feeder can be used. Furthermore, commercially available feeders can also be used as such a feeder 30. Additionally, in... Figure 4 In the compounding extruder shown, the motor 30b of the feeder 30 is electrically connected to the control device 10, thereby allowing the control device 10 to control the operation of the motor 30b. Alternatively, such a feeder 30 may also include a mass meter. With a mass meter, the amount of raw material in the feeder 30 can be managed based on mass data, allowing for more accurate control of the amount of raw material in the feeder 30, the supply rate of raw material supplied to the barrel via the hopper 3, and so on. Therefore, when using a feeder 30 including a mass meter, in order to manage the amount of raw material in the feeder 30, mass data measured using the mass meter can be input to the control device 10, allowing the control device 10 to manage the amount of raw material in the feeder simultaneously.

[0118] Furthermore, motor 4 functions as a screw drive device (rotary drive mechanism) for driving screw 2 and is connected to screw 2. There are no particular limitations on motor 4 as such a screw drive device; well-known motors used in the field of compounding extruders can be appropriately used. Additionally, in Figure 4 In the configuration shown, the motor 4 is electrically connected to the control device 10, thereby enabling the control device 10 to control the operation of the motor 4 (control the motor speed).

[0119] Furthermore, the two DA supply devices 5 are used to supply the devolatilization aid DA into the barrel 1 from the DA supply port (11A or 11B). Therefore, each DA supply device 5 is connected to the barrel in such a way that it can supply the devolatilization aid DA into the barrel 1 via the DA supply port (11A or 11B). There are no particular limitations on such DA supply devices 5; for example, if the devolatilization aid DA is water, a device including a water storage container and a gear pump connected to the container (water injection device) can be used. In addition, known DA supply devices can be appropriately used as DA supply devices 5. For example, if a gear pump as described above is used, a known gear pump (or a commercially available one) can be appropriately used. Furthermore, when using a DA supply device 5 in the form of a gear pump, the water injection volume can be controlled to a desired amount by controlling the drive (operation) of the motor that rotates the gear. Additionally, in Figure 4In the kneader extruder of the illustrated form, the DA supply device 5 is electrically connected to the control device 10, whereby the control of the operation of the DA supply device 5 (for example, the control of the rotation speed of the motor of the gear pump) can be performed by the control device 10, and the data (control data) relating to the operation condition of the DA supply device 5 can be input to the control device 10. Further, such data relating to the operation condition can be appropriately used for the management of the amount of DA of the devolatilization aid in the container.

[0120] In addition, the two pressure reducing devices 6 are respectively used for making the pressure of the region (discharge portion) in the vicinity of the devolatilization port (12A or 12B) be low pressure. Such pressure reducing device 6 is not particularly limited, and a publicly known pressure reducing device (publicly known vacuum pump or the like) used in the field of so-called discharge type extruders can be appropriately used. Here, in the illustrated form, the pressure reducing device 6 is electrically connected to the control device 10, whereby the control of the operation of the pressure reducing device 6 (vacuum pump or the like) (for example, the control of the rotation of the motor for driving the vacuum pump or the like) can be performed by the control device 10. Figure 5 In the illustrated form, the pressure reducing device 6 is electrically connected to the control device 10, whereby the control of the operation of the pressure reducing device 6 (vacuum pump or the like) (for example, the control of the rotation of the motor for driving the vacuum pump or the like) can be performed by the control device 10.

[0121] In addition, the temperature adjusting device 7 is used for heating or cooling the barrel at each arrangement position. Such temperature adjusting device 7 is arranged on the outside of the barrel 1 in a manner capable of heating or the like the barrel. As such temperature adjusting device 7, there is no particular limitation, and a publicly known heating / cooling member used in the field of extruders (for example, a member composed of a heater (may be used as a heating / cooling member by heating when the heater is operated and naturally cooling when the operation is stopped), a member composed of a heating member such as a heater and a cooling member such as a heat sink, a member composed in a manner capable of circulating a heating medium (heating liquid or cooling liquid) to heat or cool a desired site, or the like) can be appropriately used.

[0122] Further, the thermometer 8 is used for measuring the temperature of the barrel. As such thermometer 8, there is no particular limitation, and a publicly known temperature measuring device (may be a commercially available product) can be appropriately used. Further, such thermometer 8 is connected to the control device 10, whereby the temperature data calculated by the thermometer can be input to the control device 10.

[0123] In addition, the pressure gauge (pressure sensor) 9 is used for measuring the state of the pressure in the pipe connecting the devolatilization port (12A or 12B) and the pressure reducing device 6 (vacuum pump). As such pressure gauge 9, there is no particular limitation, and a publicly known pressure gauge can be appropriately used.

[0124] The control device 10 is electrically connected to the feeder 30 (particularly, the motor 30b in the feeder 30), the motor 4, the DA supply device 5, the pressure reducing device (vacuum pump) 6, the temperature adjusting device 7, and the thermometer 8. Such a control device 10 is a device used to control the operation of the motor 4 as a screw driving device, the feeder 30 (more specifically, the motor 30b in the feeder 30) as a raw material supply device, the DA supply device 5, and the temperature adjusting device 7 in such a manner that, when the raw material is transported from the upstream side to the downstream side while being mixed when a resin composition is manufactured, the filling rate of the raw material in at least one of the DA addition mixing zones (the zone between the upstream portion of the supply port in which the seal ring SR is arranged and the downstream portion of the supply port in the cylinder: the zone Al, the zone A2) or both of the zones is set to 70% or more, and the devolatilization aid DA is supplied to the raw material in the cylinder 1 from the devolatilization aid supply port, and the volatile component contained in the raw material is discharged from the devolatilization port.

[0125] Such a control device 10 can make the control of the operation of each of the above-described devices desired, and can also be constituted by a computer by appropriately combining a CPU, a ROM, a RAM, a program (such a program can be stored in the ROM and used, or can also be stored in another storage medium and used) required for various operations for performing the control, and the like. Furthermore, the specific structure thereof is not particularly limited, and to perform the control of the operation of each of the above-described devices, a structure including hardware constituted by a CPU, a memory, and the like, and a computer program (software) stored (installed) in the memory or the like for performing the required operations can also be used. Furthermore, as such a CPU, for example, a central processing device, a processing device, an operation device, a processor, a microprocessor, a microcomputer, a DSP (Digital Signal Processor), and the like can be cited.

[0126] Here, in the control device 10, a computer program (software) is used to perform calculations necessary for controlling the operation of the motor 4 (which is a screw drive device), the feeder 30 (more specifically, the motor 30b in the feeder 30) (which is a raw material supply device), the DA supply device 5, and the temperature control device 7. For example, a preferred example is a computer program programmed in such a way that it pre-determines how, when mixing raw materials while conveying them from the upstream side to the downstream side during the manufacture of a resin composition, the DA is added to the mixing zone (where a sealing ring is arranged inside the barrel) according to the type of raw material, screw structure, etc. The region between the upstream and downstream portions of the supply port of SR (region A1, region A2) is such that the filling rate of the raw material in at least one or both regions is set to 70% or more, and the devolatilization aid DA is supplied to the raw material in the barrel 1 from the devolatilization aid supply port and the volatile components contained in the raw material are discharged from the devolatilization port. The operating conditions of the motor 4, the operating conditions of the motor 30b related to the raw material supply speed, the temperature conditions of the barrel, etc., are all determined by inputting temperature data measured by the thermometer 8 into the computer during actual operation, so as to make various devices operate in a way that satisfies the predetermined conditions. Furthermore, there are no particular limitations on the method used to pre-determine the required conditions. For example, using mixing simulation software (manufactured by Nippon Steel, trade name: TEX-FAN), based on the structure of the mixing extruder, one can determine the operating conditions required to set the filling rate of the raw material in at least one or both of the DA-adding mixing zones (the zones between the upstream and downstream portions of the feed port equipped with the sealing ring SR within the barrel: zones A1 and A2) to 70% and to discharge the volatile components contained in the raw material from the devolatilization port. Hereinafter, using... Figure 5 This section briefly explains the specific methods used to determine the required operating conditions (control conditions). Furthermore, Figure 4 The process shown is used to determine the... Figure 5 The process shown is an example of an optimized operating condition in which the filling rate of the two regions A1 and A2 in the barrel of the mixing extruder is set to 70% or more.

[0127] Figure 4 This is a flowchart illustrating a preferred embodiment of the process for determining the operating conditions of various devices in a compounding extruder under the following conditions: [The flowchart describes the process of using...] Figure 5When the DA is added while the raw material is transported from the upstream side to the downstream side in the manufacturing of the resin composition in the mixing extruder, the filling rate of the raw material in the two regions of the DA addition mixing region (region A1, region A2) can be set to 70% or more, and the devolatilization aid DA is supplied to the raw material in the cylinder 1 from the devolatilization aid supply port, and the volatile components contained in the raw material are discharged from the devolatilization port. The calculation at such an operation condition is performed in Figure 5 The calculation in the flow shown is performed using a computer capable of performing a calculation based on a mixing simulation software (manufactured by Nippon Steel & Sumikin Engineering Co., Ltd., trade name: TEX-FAN).

[0128] In Figure 5 In the flow shown, in step S101, first, information of the device structure of the mixing extruder (structure of the cylinder, screw diameter, screw structure, etc.) is input to the calculation section in the computer on which a calculation is performed by the mixing simulation software, and the physical properties of the components of the raw material of the resin composition (PVT characteristics of the resin) are input.

[0129] Next, in step S102, as predetermined conditions (mixing conditions) to be adopted in order to make the desired region have the desired filling rate in the case of using the mixing extruder, the values of the following conditions (A) to (C) are input to the calculation section, and in the calculation section, a calculation of a mixing simulation based on the mixing simulation software (manufactured by Nippon Steel & Sumikin Engineering Co., Ltd., trade name: TEX-FAN) is performed: [condition (A)] rotational speed of the screw 2 (rotational speed of the motor 4, value that affects the residence time of the raw material in a specific region at the time of mixing / transporting the raw material), [condition (B)] rotational speed of the motor 30b of the feeder (rotational speed of the screw 30a for raw material supply: value for controlling the supply speed of the raw material), [condition (C)] temperature of the cylinder 1. In addition, as the input values of the conditions (A) to (C) in step S102, there is no particular limitation, and it is sufficient to input values that a person skilled in the art can estimate to be required in order to make the filling rate of the raw material in the DA addition mixing region a desired value (70% or more).

[0130] Next, in step S103, based on the results (contents) of the simulation output as the calculation results, it is determined whether the filling rate of the raw material in the DA addition mixing region (region A1, region A2) becomes a desired value of 70% or more in the transport mixing step. In the case where the result of the determination in such step S103 is that the filling rate of the raw material does not become the desired value, it proceeds to step S104, and in the case where it becomes the desired value, it proceeds to step S105.

[0131] In this case, in a case where the result of the determination in step S103 is to proceed to step S104, in this step S104, based on the result of the previous simulation (calculation), a new value different from the value used (input) at the time of the previous simulation (calculation) is input for at least one of the input values of the above conditions (A) to (C), and the calculation of the mixing simulation is performed. As to the input of the new value for at least one of the input values of such conditions (A) to (C), the following value can be input based on the result of the mixing simulation: a value estimated to be the most suitable value for making the filling rate of the raw material a desired value (70% or more). Further, such input of the new value can be performed as follows: a value calculated by a person skilled in the art in such a manner as to become a desired result based on the calculation result of the mixing simulation is input, or another calculation section that analyzes the calculation result up to this point and calculates a value required to make the filling rate of the raw material in the DA addition mixing zone (region Al, region A2) a desired value is provided in the computer, and the value calculated by the other calculation section is input to the calculation section that performs the calculation by the mixing simulation software.

[0132] Then, in a case where the result of the determination in step S103 is that the filling rate of the raw material in the DA addition mixing zone (region Al, region A2) becomes a desired value of 70% or more, the operating conditions of the motor 4 as the screw driving device, the feeder 30 (more specifically, the motor 30b in the feeder 30) as the raw material feeding device, the DA feeding device 5, and the temperature adjusting device 7 are obtained according to the conditions and the like used at this time, and the calculation is ended.

[0133] Further, by appropriately changing the set value of the desired value of the filling rate of the raw material in the DA addition mixing zone, such Figure 4 The flowchart shown above enables the operating conditions for satisfying various filling rates to be obtained in advance. In this way, in a case where the operating conditions for satisfying various filling rates are obtained in advance, in a case where a numerical value of a desired filling rate is input to the control device 10 based on data of these operating conditions, the operating conditions of each device required to satisfy the numerical value of the filling rate can also be automatically calculated in the control device 10, a computer program that controls the operation of each device in such a manner as to satisfy the operating conditions is made, and stored in the memory of the computer that constitutes the control device 10. Thus, by inputting a numerical value of a desired filling rate to the control device 10, the control of each device can also be efficiently performed.

[0134] Thus, if the control device 10 is configured by a computer that stores a computer program for controlling the operation of each device in a manner that satisfies the operation conditions calculated as described above, the operation of each device can be controlled by the control device 10 in a manner that the fill rate of the raw material in the DA addition mixing zone (zone Al, zone A2) becomes a desired value of 70% or more when the resin composition is manufactured. Further, when the operation of each device is controlled, for example, the temperature data of the cylinder calculated by the thermometer 8 can be automatically input to the control device 10, and the operation of the temperature adjusting device 7 can be controlled in a manner that the temperature of the cylinder becomes a desired temperature according to the change in the temperature.

[0135] Further, when the operation of each device is controlled in this manner, the operation of the DA supply device 5 and the operation of the pressure reducing device 6 are also controlled by the control device 10 in a manner that the fill rate of the raw material in the DA addition mixing zone is set to a desired value of 70% or more, and the devolatilizing aid DA is supplied to the raw material in the cylinder 1 from the devolatilizing aid supply port and the volatile components contained in the raw material are discharged from the devolatilizing port. Further, in order to perform the control of the operation of the DA supply device 5 and the control of the operation of the pressure reducing device 6, it is preferable that the control device 10 include a computer program programmed in a manner that, in a case where the conditions of the supply amount and the supply speed of the devolatilizing aid as a target are set, and the desired pressure (the internal pressure of the melt-kneaded material) of the region (discharge portion) in the vicinity of the devolatilizing port (12A and 12B) is set by the pressure reducing device 6, the operation of the DA supply device 5 and the operation of the pressure reducing device 6 can be controlled in a manner that satisfies these set conditions. Further, as for such a computer program for operation control, it is sufficient to be appropriately made in a manner that the control method of the known DA supply device 5 (for example, a gear motor) used in the field of the discharge-type extruder and the control method of the known pressure reducing device 6 are applied to adjust to a desired supply amount and a desired pressure. Further, for example, it is possible that the data of the pressure measured by the pressure gauge (pressure sensor) 9 is input to the control device 10, and the operation condition of the pressure reducing device 6 (for example, the rotation speed of the motor for driving the vacuum pump) is changed in a manner that the pressure of the site becomes a desired size according to the value, and the control device 10 is configured in the above-described manner to control the operation of the pressure reducing device 6 in a manner that the pressure can be maintained at a desired value.

[0136] Such a resin composition manufacturing apparatus of the embodiment illustrated in FIG. 1 can be used. Figure 4 The resin composition manufacturing method of the present application can be performed using the resin composition manufacturing apparatus of the embodiment illustrated in FIG. 1. Thus, as described above, it can be said that the resin composition manufacturing apparatus of the present application can be appropriately used for the resin composition manufacturing method of the present application. Further, the resin composition manufacturing apparatus of the present application can be appropriately used for the resin composition manufacturing method of the present application. Figure 1 The resin composition manufacturing apparatus of the embodiment illustrated in FIG. 1 is an apparatus for manufacturing a resin composition in a manner that the fill rate of the raw material in the DA addition mixing zone is set to a desired value of 70% or more, and the devolatilizing aid DA is supplied to the raw material in the cylinder 1 from the devolatilizing aid supply port and the volatile components contained in the raw material are discharged from the devolatilizing port. Figure 1In one preferred embodiment of the apparatus for the resin composition shown in the embodiment, in the raw material conveying and mixing process, except for controlling the operation of each device constituting the mixing extruder (including the amount of raw material input, etc.) using the control device 10 as described above, it is basically possible to use the same method as when using... Figure 4 The resin composition is manufactured under the same conditions described in the method for manufacturing the resin composition of the apparatus shown in the embodiment, thus omitting the raw material conveying and mixing steps, etc. Figure 4 The following is a description of the specific method for manufacturing the resin composition according to the apparatus for manufacturing the resin composition shown in the embodiment (in addition, besides using...) Figure 1 The feeder 30, motor 4, DA supply device 5, pressure reducing device 6, temperature regulating device 7, etc., as specifically described above, are controlled by the control device 10, and their operation is basically the same as that in the use of... Figure 1 In the case of the compounding extruder shown in the embodiment, the conveying and compounding process can be performed under the same conditions, and the optimal conditions for the process can also be adopted. Figure 4 The conditions described in the process of the apparatus of the illustrated embodiment are the same as those in the procedure.

[0137] The above is about Figure 1 The apparatus for manufacturing the resin composition of the illustrated embodiment has been described, but the apparatus for manufacturing the resin composition of the present invention is not limited to the above embodiment; any apparatus may be used, and other structures are not particularly limited:

[0138] A screw extruder is constituted by a barrel, a screw disposed in the barrel, a screw driving device for driving the screw, a raw material supply device for supplying a raw material into the barrel, a devolatilization aid supply device for supplying a devolatilization aid into the barrel, a temperature adjusting device for adjusting the temperature of the barrel, and a control device electrically connected to the screw driving device, the raw material supply device, the devolatilization aid supply device, and the temperature adjusting device and for controlling the operation of each device. The barrel has at least one devolatilization aid supply port and at least one devolatilization port for discharging a volatile component as an opening portion, and has at least one configuration portion in which the devolatilization aid supply port and the devolatilization port are arranged at intervals from the upstream side. The screw has at least one screw structure in which a seal ring is disposed at a supply port upstream portion located upstream of the position of the devolatilization aid supply port provided with at least one of the configuration portions in the barrel and a supply port downstream portion located between the devolatilization aid supply port and the devolatilization port of the configuration portion. The extruder satisfies the following condition: in a region between the supply port upstream portion and the supply port downstream portion in which the seal ring is disposed, no opening portion that communicates the region with the outside of the barrel is provided except for the devolatilization aid supply port that is a reference for the positions of the supply port upstream portion and the supply port downstream portion. The control device controls the operation of the screw driving device, the raw material supply device, the devolatilization aid supply device, and the temperature adjusting device in such a manner that, when the raw material is transported from the upstream side to the downstream side while being mixed in the manufacture of a resin composition, the filling rate of the raw material in at least one of the regions between the supply port upstream portion and the supply port downstream portion in the barrel in which the seal ring is disposed is set to 70% or more, the devolatilization aid is supplied to the raw material in the barrel from the devolatilization aid supply port, and the volatile component contained in the raw material is discharged from the devolatilization port.

[0139] Embodiment

[0140] Hereinafter, the present application will be more specifically described based on examples and comparative examples, but the present application is not limited to the following examples. Furthermore, in the examples and comparative examples shown below, the same pelletized recycled polypropylene (a material separated and recovered from automobiles and home appliances) was used as a raw material.

[0141] (Example 1)

[0142] The raw material formed of the recycled polypropylene was kneaded using a twin-screw extruder (TEX30 manufactured by Japan Steel Works, Ltd., ratio of length L of screw to diameter (outer diameter) D of screw (L / D) = 77, maximum outer diameter of screw (diameter of screw): 30 mm (nominal value), inner diameter of cylinder (diameter of cylinder): 32 mm) to obtain a resin composition (in pellet form). Further, the cylinder and the screw were designed in the same manner as the structure shown in Figure 1 1～4 The gap between the sealing ring and the inner diameter of the cylinder at the position where the sealing ring was disposed was 0.5 to 1 mm. In addition, in the twin-screw extruder, the ratio of the length L1 of the screw to the diameter (outer diameter) D of the screw in the portion of the region Al shown in Figure 5

[0143] Further, in Example 1, with respect to the kneading conditions of the temperature of the cylinder: 170°C, the screw rotation speed: 150 rpm, and the supply speed of the raw material to the cylinder: 5 kg / h, which were employed when the raw material was kneaded, the following kneading conditions were employed: the temperature of the cylinder: 170°C, the screw rotation speed: 150 rpm, the supply speed of the raw material to the cylinder: 5 kg / h, the amount of water injected from the devolatilizing aid supply port 11A: 14 parts by mass with respect to 100 parts by mass of the raw material in the cylinder 1, the amount of water injected from the devolatilizing aid supply port 11B: 14 parts by mass with respect to 100 parts by mass of the raw material in the cylinder 1 (in addition, the amount of water was an amount obtained in accordance with the ratio of the supply speed of the resin composition to the supply speed of water), and the amount of water injected from the devolatilizing aid supply port 11C: 14 parts by mass with respect to 100 parts by mass of the raw material in the cylinder 1 (in addition, the amount of water was an amount obtained in accordance with the ratio of the supply speed of the resin composition to the supply speed of water).​​Figure 1 The process shown (flowchart) was analyzed using mixing simulation software (manufactured by Nippon Steel, trade name: TEX-FAN) to determine the necessary mixing conditions (raw material supply rate, etc.) to set the raw material filling rate (volume %) in both DA addition mixing zones (zones A1 and A2) to 100%. Additionally, the raw material supply device used for supplying raw materials during mixing (in...) Figure 4 Illustrations omitted; please refer to the original text. Figure 4 , equivalent to Figure 1 The feeder 30 shown is a device for feeding the screw, and the screw drive device (a rotary drive mechanism that rotates the screw) is a rotary drive mechanism that rotates the screw. Figure 4 Illustrations omitted; please refer to the original text. Figure 4 , equivalent to Figure 1 The device shown is a motor 4), and a heater is used to adjust the temperature inside the barrel. Figure 4 Illustrations omitted; please refer to the original text. Figure 4 , equivalent to Figure 1 The operation of the temperature regulating devices 7 shown is controlled by a computer electrically connected to them (in... Figure 4 Illustrations omitted; please refer to the original text. Figure 4 , equivalent to Figure 1 The control device 10 shown controls the flow by setting the barrel temperature to 170°C, the screw speed to 150 rpm, and the feed rate of the raw material to the barrel to 5 kg / h. Furthermore, to ensure that the amount of water injected through the self-volatilizing agent supply port 11A meets the above conditions, [further details are needed]. Figure 4 The apparatus for supplying the devolatilization aid is omitted from the diagram (see reference). Figure 4 , equivalent to Figure 1 The operation of the DA supply device 5 shown is also controlled by a computer electrically connected to the device. Figure 4 Illustrations omitted; please refer to the original text. Figure 4 , equivalent to Figure 1 The control device 10 shown is used for control. Furthermore, during the mixing of raw materials, a water-sealed vacuum pump connected to the devolatilization ports (outlets) 12A and 12B is used. Figure 4 Illustrations omitted; please refer to the original text. Figure 4 , equivalent to Figure 2 The operation of the pressure reducing device 6 shown is also controlled by a computer electrically connected to the water-sealed vacuum pump. Figure 1 Illustrations omitted; please refer to the original text. Figure 1 , equivalent to Figure 1 The control device 10 shown is used to control the pressure inside the barrel, thereby reducing the pressure.

[0144] (Example 2)

[0145] The design of the barrel and screw is intended to be compatible with... Figure 3The structure shown is the same as the one shown, but with a modified form (in addition, the screw structure is configured from upstream to downstream in the order of FS, KD1, FS, SR1, KD2, FS, KD2, SR2, FS, SR3, KD3, FS, KD3, SR4, FS), and the length of the screw in region A1 is increased (equivalent to...). Figure 2 The ratio (L1 / D) of L1 to the screw diameter (outer diameter) D is changed to 8.25, and the length of the screw in part of region A2 (equivalent to...) is... Figure 6 The ratio of L2 to the screw diameter (outer diameter) D (L2 / D) is changed to 6.25, and the length between the upstream end of the sealing ring SR1 and the downstream end of the raw material supply port (equivalent to...) is changed. ​ The length of the L3 portion was changed to 1267.5 mm. The length-to-diameter ratio (length / diameter) of the threaded screw FS in region A1 was set to 1.25, the length-to-diameter ratio of the threaded screw FS in region A2 was set to 1.25, and the length-to-diameter ratio (length / diameter) of the screw in the portion consisting of the kneading disc KD1 was set to 8. Otherwise, the raw materials were mixed in the same manner as in Example 1 to obtain a resin composition. The filling rate (volume %) of the raw materials in regions A1 and A2 was determined in the same manner as in Example 1. The results showed that the filling rate of the raw materials in region A1 was 93%, and the filling rate of the raw materials in region A2 was 87%.

[0146] (Example 3)

[0147] The design of the barrel and screw is intended to be compatible with... ​ The structure shown is the same as the modified structure (in addition, except that the devolatilization aid supply port 11B is not formed, it becomes the same as the structure shown). ​ The same design as shown was used, except that water was injected only from the devolatilization aid supply port 11A. The raw materials were mixed in the same manner as in Example 2 to obtain a resin composition. The filling rate (volume %) of the raw materials in the water injection area A1 was determined in the same manner as in Example 1, and the filling rate was found to be 93%.

[0148] (Comparative Example 1)

[0149] The design of the barrel and screw is intended to be compatible with... ​The structure of the screw structure shown was changed in the same manner as in Example 1 (in addition, the screw structure was arranged in the order of FS, KD1, FS, SR1, KD2, FS, SR2, FS, SR3, KD3, FS, SR4, FS from the upstream side toward the downstream side. Here, the ratio of the length to the diameter of the screw (corresponding to L1 / D and L2 / D) in each of the regions Al and A2 was not changed, the screw structure in the region Al was changed to a structure composed of a kneading disk KD2 and a flighted screw FS, and the screw structure in the region A2 was changed to a structure composed of a kneading disk KD3 and a flighted screw FS), the ratio of the length to the diameter (length / diameter) of the flighted screw FS arranged in the region Al was set to 6.5, the ratio of the length to the diameter (length / diameter) of the flighted screw FS arranged in the region A2 was set to 6.5, and otherwise, the raw materials were kneaded in the same manner as in Example 1 to obtain a resin composition. The raw material fill rates (vol%) in the regions Al and A2 were determined in the same manner as in Example 1, and as a result, the raw material fill rate in the region Al was 34%, and the raw material fill rate in the region A2 was 34%.

[0150] (Comparative Example 2)

[0151] The raw material supply rate to the cylinder was changed to 15 kg / h, and otherwise, the raw materials were kneaded in the same manner as in Comparative Example 1 to obtain a resin composition. The raw material fill rates (vol%) in the regions Al and A2 were determined in the same manner as in Example 1, and as a result, the raw material fill rate in the region Al was 48%, and the raw material fill rate in the region A2 was 48%.

[0152] [Evaluation of the properties of the resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 and 2]

[0153] Respective directly using the raw material of the recycled polypropylene (pellet), the resin composition (pellet) obtained in Examples 1 to 3 and Comparative Examples 1, 2, respectively, prepared their measuring sample (20 to 50 mg). Then, using a thermal desorption (TD) - gas chromatography mass spectrometry analysis device (device structure: TDU manufactured by Gerstel Co., Ltd. and trade name: 7890B GC-5977B MSD manufactured by Agilent Co., Ltd.), the gas component (volatile organic compound: volatile organic compound) generated when the sample was heated at 80°C for 10 minutes was analyzed. In addition, the TD-based heating generated gas was concentrated and captured at a cooling injection port (CIS, Tenax-TA was filled into the insert, temperature: -50°C), and then, the CIS was rapidly heated from -50°C to 300°C at a temperature rising rate: 720°C / minute, and separated using a column (manufactured by Agilent Co., Ltd., trade name: HP-5MS UI, length 30 m, inner diameter 0.25 mm, film thickness 0.25 μm). As the carrier gas of the column, He (flow rate: 1.5 mL / minute) was used, and the temperature of the column was raised from 0°C to 300°C at a temperature rising rate: 10°C / minute. Then, the components separated by the column were detected using a mass spectrometer (electron ionization method, ion source temperature: 230°C, MS quadrupole rod temperature: 150°C, m / z value of the scan range: 28.7-600). Then, the integral value of the total ion current (TIC) chromatogram of the range of m / z value of 33 to 600 was defined as the amount of volatile organic compound contained in the sample, and the amount of volatile organic compound contained per 1 mg of the sample was calculated for each sample of the raw material (pellet before mixing) and the resin composition (pellet after mixing) obtained in each example, and the removal rate of volatile organic compound (the proportion of volatile organic compound removed from the raw material) was calculated by using the following calculation formula (1):

[0154] [Removal rate of volatile organic compound (%)]= (M1-M2) / M1 (1).

[0155] (In formula (1), M1 represents the amount of volatile organic compound contained per 1 mg of the sample of the raw material (the amount of volatile organic compound in the raw material before devolatilization), and M2 represents the amount of volatile organic compound contained per 1 mg of the sample of the resin composition after mixing (pellet after mixing) obtained in each example (the amount of volatile organic compound remaining in the resin composition obtained after devolatilization).

[0156] The obtained results are shown in Table 1.

[0157] Further, in Table 1, the ratio of the length of the screw L1 to the screw diameter D (L1 / D) of the screw L1 disposed in the water injection region Al and the ratio of the length of the screw L2 to the screw diameter D (L2 / D) of the screw L2 disposed in the water injection region A2 are collectively shown, and the filling rate of the raw material in the water injection region Al and the water injection region A2 (vol%) is collectively shown.

[0158] [Table 1]

[0159]

[0160] From the results shown in Table 1, in Examples 1 to 3 which are the methods equivalent to the method for producing the resin composition of the present application in which the filling rate of the raw material (melt-kneaded product) in the region where the kneading devolatilization aid (water) is added (Examples 1 and 2: regions Al and A2, Example 3: region Al) is set to 70% or more, in the devolatilization step, the volatile organic compounds (VOC) in the raw material are efficiently removed at a high level (a removal rate of 85% or more is a high level), and it is confirmed that the resin composition in which the residual amount of VOC is sufficiently low can be efficiently produced by this method. On the contrary, in the methods employed in Comparative Examples 1 and 2 in which the filling rate of the raw material (melt-kneaded product) in the region where the kneading devolatilization aid (water) is added is less than 70%, the removal rate of VOC becomes 48% or less, and the volatile organic compounds (VOC) cannot be sufficiently devolatilized and removed.

[0161] Industrial applicability

[0162] As explained above, according to the present application, it is possible to provide a method for producing a resin composition in which the residual amount of volatile organic compounds is sufficiently low, which can efficiently produce the resin composition, and a production apparatus for the resin composition which can be appropriately used for the method. Therefore, the method for producing a resin composition of the present application is useful, for example, as a method for producing a recycled resin composition in which VOC is removed, a method for obtaining a resin composition in which VOC is removed and deodorized, and the like.

[0163] Explanation of reference numerals

[0164] 1, cylinder; 2, screw; 3, hopper; 4, motor for driving the screw 2; 5, devolatilization aid supply device; 6, pressure reducing device (vacuum pump); 7, temperature adjusting device; 8, thermometer; 9, pressure gauge (pressure sensor); 10, control device (controller); 11A, 11B, devolatilization aid supply port; 12A, 12B, devolatilization port for discharging volatile components; 13, opening portion (raw material supply port) for supplying raw material; 30, feeder; 30a, screw for raw material supply; 30b, motor for driving the screw for raw material supply; FS, full flight screw; KD 1～3 , kneading disc; SR1～4 , sealing ring; DA, devolatilization aid; VOC, volatile organic compound.

Claims

1. A method for producing a resin composition, wherein the method for producing a resin composition comprises: a kneader extruder preparation step in which a kneader extruder is prepared, the kneader extruder includes a barrel and a screw disposed in the barrel, the barrel has at least one devolatilization aid supply port and at least one devolatilization port for discharging a volatile component as an opening portion, and has at least one configuration portion in which the devolatilization aid supply port and the devolatilization port are arranged at intervals from an upstream side, the screw has at least one screw structure in which a seal ring is disposed at a supply port upstream portion located on an upstream side of a position of the devolatilization aid supply port provided with at least one of the configuration portions in the barrel and a supply port downstream portion located between the devolatilization aid supply port and the devolatilization port of the configuration portion, and in a region between the supply port upstream portion and the supply port downstream portion in which the seal ring is disposed, no opening portion that communicates the region with the outside of the barrel is provided except for the devolatilization aid supply port that is a reference for positions of the supply port upstream portion and the supply port downstream portion; and a conveying kneading step in which, using the kneader extruder, the screw is used to convey and knead a raw material of a resin composition supplied into the barrel from an upstream side to a downstream side, in the conveying kneading step, a fill rate of the raw material in at least one of the regions between the supply port upstream portion and the supply port downstream portion in the barrel in which the seal ring is disposed is set to 70% or more, a devolatilization aid is supplied from the devolatilization aid supply port to the raw material in the barrel, and a volatile component included in the raw material is discharged from the devolatilization port, thereby obtaining a resin composition.

2. The method for producing a resin composition according to claim 1, wherein in the conveying kneading step, the fill rate of the raw material in the region between the supply port upstream portion and the supply port downstream portion in the barrel in which the seal ring is disposed is set to 80% or more.

3. The method for producing a resin composition according to claim 1, wherein the devolatilization aid is water.

4. An apparatus for producing a resin composition, wherein the apparatus for producing a resin composition is constituted by a kneader extruder that includes: a barrel; a screw disposed in the barrel; a screw driving device for driving the screw; a raw material supply device for supplying a raw material into the barrel; a devolatilization aid supply device for supplying a devolatilization aid into the barrel; a temperature adjusting device for adjusting a temperature of the barrel; and a control device electrically connected to the screw driving device, the raw material supply device, the devolatilization aid supply device, and the temperature adjusting device and for controlling the operation of the devices. The cylinder has at least one devolatilization aid supply port and at least one devolatilization port as an opening portion for discharging a volatile component, and has at least one configuration portion in which the devolatilization aid supply port and the devolatilization port are arranged at intervals from an upstream side, The screw has at least one screw structure in which a seal ring is provided at a supply port upstream portion located on an upstream side of a position of the devolatilization aid supply port provided with the at least one configuration portion and a supply port downstream portion located between the devolatilization aid supply port and the devolatilization port of the configuration portion in the cylinder, The mixing extruder satisfies a condition in which, in a region between the supply port upstream portion and the supply port downstream portion in which the seal ring is provided, no opening portion that communicates the region with the outside of the cylinder is provided except for the devolatilization aid supply port that is a reference for positions of the supply port upstream portion and the supply port downstream portion, The mixing extruder is a device used to manufacture a resin composition by mixing while conveying a raw material of a resin composition supplied into the cylinder from an upstream side to a downstream side using the screw, The control device controls the operation of the screw drive device, the raw material supply device, the devolatilization aid supply device, and the temperature adjustment device in such a manner that, when mixing is performed while the raw material is conveyed from the upstream side to the downstream side when manufacturing the resin composition, a fill rate of the raw material in at least one region of a region between the supply port upstream portion and the supply port downstream portion in the cylinder in which the seal ring is provided is set to 70% or more, and the raw material in the cylinder is supplied with a devolatilization aid from the devolatilization aid supply port and a volatile component included in the raw material is discharged from the devolatilization port.

5. The resin composition manufacturing device according to claim 4, wherein The mixing extruder further includes a pressure reduction device connected to the devolatilization port, The control device is further electrically connected to the pressure reduction device, and The control device controls the operation of the screw drive device, the raw material supply device, the devolatilization aid supply device, and the temperature adjustment device and controls the operation of the pressure reduction device when manufacturing the resin composition.

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