WO2021106795A1 - 熱可塑性樹脂発泡粒子の製造方法および製造装置 - Google Patents

熱可塑性樹脂発泡粒子の製造方法および製造装置 Download PDF

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Publication number
WO2021106795A1
WO2021106795A1 PCT/JP2020/043448 JP2020043448W WO2021106795A1 WO 2021106795 A1 WO2021106795 A1 WO 2021106795A1 JP 2020043448 W JP2020043448 W JP 2020043448W WO 2021106795 A1 WO2021106795 A1 WO 2021106795A1
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Prior art keywords
thermoplastic resin
cutter
foamed particles
die
resin
Prior art date
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Ceased
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PCT/JP2020/043448
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English (en)
French (fr)
Japanese (ja)
Inventor
光孝 下田
祐紀 飛松
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Kaneka Corp
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Kaneka Corp
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Publication date
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Priority to EP20893499.2A priority Critical patent/EP4067032A4/en
Priority to JP2021561383A priority patent/JP7628963B2/ja
Publication of WO2021106795A1 publication Critical patent/WO2021106795A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
    • B29B7/58—Component parts, details or accessories; Auxiliary operations
    • B29B7/72—Measuring, controlling or regulating
    • B29B7/726—Measuring properties of mixture, e.g. temperature or density
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
    • B29B7/58—Component parts, details or accessories; Auxiliary operations
    • B29B7/582—Component parts, details or accessories; Auxiliary operations for discharging, e.g. doors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/74—Mixing; Kneading using other mixers or combinations of mixers, e.g. of dissimilar mixers ; Plant
    • B29B7/7404—Mixing devices specially adapted for foamable substances
    • B29B7/7409—Mixing devices specially adapted for foamable substances with supply of gas
    • B29B7/7414—Mixing devices specially adapted for foamable substances with supply of gas with rotatable stirrer, e.g. using an intermeshing rotor-stator system
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/80—Component parts, details or accessories; Auxiliary operations
    • B29B7/88—Adding charges, i.e. additives
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B9/00—Making granules
    • B29B9/02—Making granules by dividing preformed material
    • B29B9/06—Making granules by dividing preformed material in the form of filamentary material, e.g. combined with extrusion
    • B29B9/065—Making granules by dividing preformed material in the form of filamentary material, e.g. combined with extrusion under-water, e.g. underwater pelletizers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B9/00—Making granules
    • B29B9/12—Making granules characterised by structure or composition
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/001—Combinations of extrusion moulding with other shaping operations
    • B29C48/0022—Combinations of extrusion moulding with other shaping operations combined with cutting
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/05—Filamentary, e.g. strands
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/30—Extrusion nozzles or dies
    • B29C48/345—Extrusion nozzles comprising two or more adjacently arranged ports, for simultaneously extruding multiple strands, e.g. for pelletising
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
    • C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
    • C08J9/122—Hydrogen, oxygen, CO2, nitrogen or noble gases
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/16—Making expandable particles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
    • B29B7/34—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices
    • B29B7/38—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary
    • B29B7/40—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with single shaft
    • B29B7/42—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with single shaft with screw or helix
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
    • B29B7/34—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices
    • B29B7/38—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary
    • B29B7/46—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft
    • B29B7/48—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft with intermeshing devices, e.g. screws
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2201/00—Foams characterised by the foaming process
    • C08J2201/02—Foams characterised by the foaming process characterised by mechanical pre- or post-treatments
    • C08J2201/03—Extrusion of the foamable blend
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2203/00—Foams characterized by the expanding agent
    • C08J2203/06—CO2, N2 or noble gases
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2300/00—Characterised by the use of unspecified polymers
    • C08J2300/22—Thermoplastic resins
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
    • C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
    • C08J2323/10—Homopolymers or copolymers of propene
    • C08J2323/12—Polypropene

Definitions

  • the present invention relates to a method and an apparatus for producing thermoplastic resin foamed particles.
  • the extrusion foaming method is known as a method for obtaining thermoplastic resin foamed particles.
  • thermoplastic resin and a foaming agent are supplied to an extruder, and then melt-kneaded and cooled to obtain a foamable molten resin (a molten resin containing a foaming agent). Then, the foamable molten resin (the molten resin containing the foaming agent) is extruded into a low pressure region through a pore die attached to the tip of the extruder and shredded to obtain thermoplastic resin foam particles.
  • the extrusion foaming method using carbon dioxide gas having a small environmental load as the foaming agent has lower gas retention during foaming than the extrusion foaming method using an organic foaming agent. Therefore, it is particularly difficult to obtain foamed particles having a high foaming ratio by the extrusion foaming method using carbon dioxide gas.
  • the shredding method for obtaining foamed particles by the extrusion foaming method is roughly divided into a cold cut method and a die face cut method.
  • the cold cut method include a method in which a molten resin containing a foaming agent extruded from a pore die is foamed, and a strand-shaped foam is taken up while being cooled through a water tank and then shredded (strand cut method).
  • the die face cutting method is a method of cutting the molten resin extruded from the pore die with a rotating cutter while contacting the die surface or ensuring a slight gap.
  • the die face cut method can be further divided into the following three methods according to the difference in the cooling method. That is, the underwater cut (hereinafter, sometimes referred to as UWC) method, the watering cut (hereinafter, sometimes referred to as WRC) method, and the hot cut (hereinafter, sometimes referred to as HC) method.
  • UWC underwater cut
  • WRC watering cut
  • HC hot cut
  • the UWC method is a method in which a chamber attached to the tip of a die is filled with cooling water adjusted to a predetermined pressure so as to be in contact with the resin discharge surface of the die, and the molten resin extruded from the pore die is cut in water. ..
  • a cooling drum in which cooling water flows along the inner peripheral surface is connected to the downstream side from the die, and the molten resin cut by a cutter in the air is cooled while foaming or after foaming. It is a method of cooling in water.
  • the UWC method and the WRC method are characterized in that the cooling water is also used for transporting the cooling water to the water separator while cooling the resin.
  • the HC method does not take the method of transporting while cooling the resin such as the cooling water flowing through the cooling drum.
  • the molten resin cut by the cutter in the air is cooled in the air while foaming or after foaming.
  • the method of transporting the foamed particles is generally performed by air transport.
  • Patent Document 1 For example, in the technique described in Patent Document 1, a hot cut pelletizer used in the HC method is used.
  • the hot-cut pelletizer described in Patent Document 1 is used for pelletizing an unfoamed thermoplastic resin to an appropriate size.
  • Patent Document 2 describes a method for producing a thermoplastic resin by the WRC method.
  • Patent Documents 3 and 4 disclose a technique for producing thermoplastic resin foamed particles by the UWC method.
  • thermoplastic resin foamed particles When attempting to produce thermoplastic resin foamed particles by the HC method as disclosed in Patent Document 1 or the WRC method as disclosed in Patent Document 2, there is a problem that the foamed particles adhere to each other in the manufacturing process. .. On the other hand, when it is attempted to produce thermoplastic resin foamed particles using carbon dioxide gas as a foaming agent by the UWC method as disclosed in Patent Documents 3 and 4, it is difficult to obtain foamed particles having a high foaming ratio. ..
  • the conventional method is a method for producing thermoplastic resin pellets. Since the thermoplastic resin pellets are basically strongly affected by gravity, they fall downward. On the other hand, since the thermoplastic resin foam particles have a low density, they are strongly affected by the wind generated in the cutter case. Therefore, the thermoplastic resin foamed particles have a long residence time in the case. As a result, the foamed particles collide with each other many times, and mutual adhesion is likely to occur. Furthermore, since static electricity is also likely to be generated, the foamed particles are likely to aggregate with each other due to static electricity, and the foamed particles are likely to adhere to each other. Therefore, with the conventional method, it is difficult to prevent the thermoplastic resin foamed particles from adhering to each other in the manufacturing process and to obtain the thermoplastic resin foamed particles having a high foaming ratio.
  • One aspect of the present invention is to prevent the thermoplastic resin foamed particles from adhering to each other in the manufacturing process and to obtain the thermoplastic resin foamed particles having a high foaming ratio.
  • the production method is a method for producing foamed thermoplastic resin particles, which is a melt-kneading step of melt-kneading a thermoplastic resin and carbon dioxide gas as a foaming agent.
  • the hot-cut method includes a granulation step of granulating thermoplastic resin foamed particles by a hot-cut method, and the hot-cut method extrudes a molten resin containing the thermoplastic resin and the foaming agent through a hole in a die. It is a step of cutting the molten resin extruded from the hole of the die with a cutter in the air and cooling the molten resin in the air while foaming or after foaming.
  • water is used. It also has a step of ejecting a mixed mist of air toward the hole of the die, and is characterized in that the spray flow rate of water by the nozzle is 1 L / h to 9 L / h per nozzle in the step.
  • the manufacturing apparatus is a manufacturing apparatus for thermoplastic resin foamed particles, which is an extruder that melts and kneads the thermoplastic resin and carbon dioxide gas as a foaming agent, and is extruded from the extruder.
  • a die having a hole through which the thermoplastic resin and the molten resin containing the foaming agent pass, and a cutter for cutting the molten resin passing through the hole of the die in air, and the thermoplastic resin by a hot-cut method. It is characterized in that it includes a granulation portion for granulating foamed particles, and is provided with at least one spray port for spraying water, and the spray port is installed toward a hole in the die. ..
  • thermoplastic resin foamed particles it is possible to prevent the thermoplastic resin foamed particles from adhering to each other in the manufacturing process and to obtain the thermoplastic resin foamed particles having a high foaming ratio.
  • FIG. 1 It is a figure which shows the schematic structure of the manufacturing apparatus of the thermoplastic resin foam particle which concerns on one Embodiment of this invention.
  • 2010 is a front view showing the internal configuration of the granulation portion of the manufacturing apparatus shown in FIG. 1, and 2010 is a front view schematically showing the positional relationship between the mist nozzle and the die.
  • FIG. 1 is a diagram showing a schematic configuration of a thermoplastic resin foamed particle manufacturing apparatus 10 according to the present embodiment.
  • 2010 of FIG. 2 is a front view showing the internal configuration of the granulation portion A of the manufacturing apparatus 10.
  • the manufacturing apparatus 10 extrudes a molten resin containing a thermoplastic resin and carbon dioxide gas as a foaming agent (hereinafter, may be simply referred to as a molten resin) and cuts it in the air to granulate the thermoplastic resin foam particles. It is a device for doing.
  • the manufacturing apparatus 10 includes an extruder 1 for extruding a molten resin, a feeder 2, a foaming agent supply unit 3, a transport unit 4, a cooling unit 5, and a granulation unit A. And have.
  • the feeder 2 and the foaming agent supply unit 3 are connected to the extruder 1.
  • the extruder 1, the transport unit 4, the cooling unit 5, and the granulation unit A are connected.
  • the extruder 1, the transport section 4, the cooling section 5, and the granulation section A are arranged in this order from the upstream side to the downstream side in the extrusion direction of the molten resin.
  • the transport unit 4 can be omitted if the resin pressure in the pipe from the extruder 1 to the granulation unit A is sufficiently low. Further, the transport unit 4 and the cooling unit 5 may be provided in a different order with respect to the arrangement order shown in FIG. Further, the transport unit 4 may be provided on both the upstream side and the downstream side of the cooling unit 5. Further, when the resin temperature is sufficiently lowered at the outlet of the extruder 1, the cooling unit 5 may be omitted.
  • the raw material such as the thermoplastic resin is supplied to the extruder 1 via the feeder 2, and the foaming agent is supplied to the extruder 1 via the foaming agent supply unit 3 (ii).
  • the thermoplastic resin and the foaming agent in the extruder 1 are melt-kneaded.
  • the melt-kneaded molten resin passes through the transport section 4 and the cooling section 5 and reaches the granulation section A.
  • the molten resin is granulated while being foamed in the granulation portion A, so that the foamed particles P are produced.
  • the extruder 1 side is the upstream side and the granulation portion A side is the downstream side with respect to the flow of the molten resin from the extruder 1 to the granulation portion A.
  • the extruder 1 can be appropriately selected from conventionally known extruders according to the type of resin to be granulated and used, and examples thereof include an extruder using a screw.
  • a screw As the extruder using the screw, for example, a single-screw extruder or a twin-screw extruder can be adopted.
  • the feeder 2 When a single-screw extruder is adopted, the feeder 2 can be omitted.
  • twin-screw extruder When a twin-screw extruder is used, the screw rotation direction may be the same direction or different directions.
  • the feeder 2 is composed of a member for supplying a thermoplastic resin. Although one feeder 2 is provided in FIG. 1, the number of feeders 2 can be appropriately set according to the characteristics, type, number, and the like of the raw materials of the thermoplastic resin foamed particles.
  • the foaming agent supply unit 3 is composed of a member that supplies a foaming agent to the molten resin that is melt-kneaded by the extruder 1. More specifically, the foaming agent supply unit 3 includes a foaming agent storage unit 3a and a pump 3b. In the foaming agent supply unit 3, the pump 3b supplies the foaming agent stored in the foaming agent storage unit 3a to the extruder 1.
  • the foaming agent is carbon dioxide gas
  • the foaming agent storage unit 3a is a carbon dioxide gas cylinder
  • the pump 3b is a high-pressure pump.
  • the transport unit 4 is composed of a transport member for transporting the molten resin from the extruder 1 to the granulation unit A.
  • the transport member may be any known transport member used in the extrusion foaming method, for example, a gear pump.
  • the gear pump is a useful member for maintaining the pressure of the flow of the molten resin or appropriately increasing the pressure.
  • the cooling unit 5 is composed of a cooling member that cools the molten resin transported from the transport unit 4 (extruder 1 if the transport unit 4 is omitted).
  • the cooling member may be a known cooling member used in the extrusion foaming method. Examples of the cooling member include a single-screw extruder, a static mixer, and the like.
  • the molten resin is cooled to a predetermined temperature by slowly cooling while mixing at a low shear rate with a single-screw extruder or a static mixer.
  • the raw materials such as the thermoplastic resin supplied via the feeder 2 are melt-kneaded in the extruder 1.
  • the barrel temperature for melting the raw material is not particularly limited as long as it does not interfere with the supply of the foaming agent to the raw material. If the thermoplastic resin is not melted at the position where the foaming agent is supplied in the extruder 1, the foaming agent may escape to the upstream side of the extruder 1. Therefore, it is preferable to set the barrel temperature so that the foaming agent does not vaporize due to the high resin temperature while completely melting the thermoplastic resin.
  • the thermoplastic resin is a polypropylene resin
  • the thermoplastic resin is preferably melt-kneaded at a barrel temperature of 180 ° C. or higher and 220 ° C. or lower.
  • the foaming agent is mixed by the foaming agent supply unit 3 in the extruder 1. Then, the molten resin containing the thermoplastic resin and the foaming agent moves while being further kneaded, passes through the transport section 4 and the cooling section 5, and reaches the granulation section A. Then, the molten resin is granulated at the granulation portion A and foamed to produce the foamed particles P.
  • the granulation section A includes a die 6, a cutter 7, a mist nozzle 8, and a cutter case 9 (collection section).
  • the cutter case 9 is a tubular housing that houses at least the cutter blade 7a of the cutter 7 and the mist nozzle 8.
  • the side-cut type granulated portion A is illustrated in FIGS. 1 and 2, the center-cut type may be used.
  • the granulation part A has a structure in which the molten resin is granulated by the HC method instead of the UWC method. Therefore, the inside of the cutter case 9 is not filled with water or the like.
  • the die 6 is arranged on the most downstream side in the flow of the molten resin.
  • the die 6 has a resin discharge surface 6a on which the molten resin extruded from the extruder 1 is discharged.
  • a die hole 6b through which the molten resin extruded from the extruder 1 passes is formed on the resin discharge surface 6a.
  • the cutter 7 is a member that cuts the molten resin discharged from the resin discharge surface 6a through the die hole 6b of the die 6.
  • the cutter 7 has a plurality of cutter blades 7a, an air discharge port 7b, and a rotating shaft portion 7c.
  • the cutter blade 7a is provided on the downstream side of the rotating shaft portion 7c, and rotates around the axis of the rotating shaft portion 7c.
  • the cutter blade 7a is configured to press the resin discharge surface 6a of the die 6 or secure a slight gap while rotating.
  • the manufacturing apparatus 10 shown in FIGS. 1 and 2 is a side-cut type apparatus in which the rotating shaft portion 7c of the cutter 7 is arranged so as to be offset from the central axis N of the die 6.
  • the air discharge port 7b is arranged behind the cutter blade 7a in the rotation direction. Further, the air discharge port 7b is configured to discharge air forward in the rotation direction of the cutter blade 7a. As a result, in the granulation portion A, air is blown from the air discharge port 7b to the molten resin immediately after being cut by the cutter blade 7a. By providing the air discharge port 7b in this way, after cutting the cutter blade 7a, the blade separation of the molten resin from the cutter blade 7a becomes good. Further, in the manufacturing apparatus 10, a water outlet can be arranged instead of the air discharge port 7b.
  • the mist nozzle 8 sprays cooling water onto the resin discharge surface 6a of the die 6.
  • 2020 of FIG. 2 is a front view schematically showing the positional relationship between the mist nozzle 8 and the die 6.
  • the mist nozzle 8 includes at least one spray port 8a for spraying water.
  • the mist nozzle 8 is provided at a position where it can be sprayed toward the resin discharge surface 6a of the die 6. That is, the spray port 8a is arranged toward the die hole 6b of the die 6.
  • the mixed mist M of water and air sprayed from the spray port 8a fills the space in the vicinity of the die hole 6b of the die 6.
  • One mist nozzle 8 may be provided or a plurality of mist nozzles 8 may be provided as long as the cooling water is sprayed on all the die holes 6b.
  • the spray flow rate of the mist nozzle 8 is 1 L / h to 9 L / h per nozzle, preferably 3 L / h to 9 L / h, and more preferably 3 L / h to 6 L / h. If the spray flow rate is smaller than 1 L / h, the foamed particles will be insufficiently cooled, and the foamed particles will easily adhere to each other. Further, if the spray flow rate is larger than 9 L / h, the die 6 is excessively cooled, and the die holes 6b are easily blocked by the molten resin.
  • the average spray particle size of the water is preferably 40 ⁇ m or less, and more preferably 35 ⁇ m or less. If the average spray particle size is larger than 40 ⁇ m, the die 6 is likely to be cooled, and the die holes 6b are likely to be clogged with the molten resin. For this reason, the cooling efficiency of the foamed particles deteriorates, so that the foamed particles tend to adhere to each other.
  • the mist nozzle 8 is preferably a two-fluid nozzle. Water and air are supplied to the inside of the two-fluid nozzle. Then, a mixed mist M of water and air is generated inside the nozzle.
  • the cutter case 9 is a portion that houses the cutter 7 and collects the foamed particles P produced by the HC method.
  • a discharge port 9c for discharging the produced foamed particles P is provided in the lower part of the cutter case 9.
  • the side wall surface 9a of the cutter case 9 has a foamed particle collision region 9a1. More specifically, the side wall surface 9a has a foamed particle collision region 9a1, a cylindrical side surface region 9a2, and a planar region 9a3.
  • the cylindrical side surface region 9a2 is located between the foamed particle collision region 9a1 and the planar region 9a3.
  • the foamed particle collision region 9a1 is a region connecting the end of the cylindrical side surface region 9a2 and the discharge port 9c.
  • the planar region 9a3 is a region in the cylindrical side surface region 9a2 that connects the end opposite to the foamed particle collision region 9a1 and the discharge port 9c.
  • the cylindrical side surface region 9a2 has a cylindrical side surface along the rotation trajectory of the cutter blade 7a. The central axis of the cylindrical side surface region 9a2 substantially coincides with the rotating shaft portion 7c.
  • the foamed particle collision region 9a1 is subjected to a non-adhesive coating treatment. That is, the coating layer 9b is formed in the foamed particle collision region 9a1.
  • the coating layer 9b is provided to prevent the foamed particles P from adhering to the foamed particle collision region 9a1. Since the coating layer 9b is formed, the foamed particles P do not adhere to the foamed particle collision region 9a1.
  • the material constituting the coating layer 9b is not particularly limited as long as it does not adhere to the foamed particles P, but preferred examples include fluororesin, polyetheretherketone, and silicone rubber.
  • the molten resin transported to the granulation portion A is extruded from the die holes 6b of the die 6. Then, when the molten resin is discharged from the die hole 6b of the resin discharge surface 6a of the die 6, it is cut into granules by the cutter 7 and granulated. Immediately after that, the granulated molten resin is separated from the cutter blade 7a by the air from the air discharge port 7b. Then, the molten resin foams in the atmospheric pressure atmosphere in the cutter case 9. As a result, the foamed particles P foamed to the foaming ratio required for the product are produced.
  • the foamed particles P referred to here include not only particles foamed to a desired foaming ratio as a product, but also particles that start foaming after being cut into particles by a cutter 7 and particles that are in the process of foaming.
  • the foamed particles P cut by the cutter 7 move to the discharge port 9c along the track Q shown in FIG. 2 by the air flow generated by the rotation of the cutter blade 7a. More specifically, the foamed particles P move toward the cutter blade 7a to foamed particles collide region 9a1 (tracks Q 1). After colliding with the foamed particle bombardment region 9a1 (coating layer 9b), said foamed particles P move along the cylindrical side regions 9a2 and a planar region 9a3 (tracks Q 2), outside the manufacturing apparatus 10 from the discharge port 9c Is discharged to.
  • a mist nozzle 8 for spraying cooling water on the molten resin cut by the cutter 7 is provided. Therefore, the space in which the foamed particles P immediately after being cut by the cutter 7 exists has an atmosphere in which the mist concentration is higher than in other spaces. Therefore, the cutter 7 cuts the molten resin in an atmosphere having a high mist concentration. Therefore, mist adheres to the surface of the foamed particles P immediately after cutting. Since the mist adhering to the surface of the foamed particles P is vaporized to promote the surface solidification of the foamed particles P, the foamed particles P do not adhere to each other. Further, the mist does not cause aggregation and adhesion of the foamed particles P due to static electricity.
  • the mist nozzle 8 for spraying the cooling water on the molten resin cut by the cutter 7 is provided, it is possible to prevent the foamed particles P from adhering to each other.
  • the molten resin is extruded from the die holes 6b and sequentially cut by a plurality of cutter blades 7a. Then, each time the cutter blade 7a cuts, the foamed particles P collide with the foamed particle collision region 9a1 in sequence.
  • the foamed particles P collide with the foamed particle collision region 9a1 in a very short time (for example, within 0.02 seconds). At the time of collision with the foamed particle collision region 9a1, the foamed particles P are not completely solidified.
  • the foamed particles P (sometimes referred to as the first foamed particles P) cut by a certain cutter blade 7a collide with the foamed particle collision region 9a1 and then adhere to the foamed particle collision region 9a1 to collide with the foamed particles. Stay within region 9a1. Then, while the first foamed particles P remain in the foamed particle collision region 9a1, the foamed particles P (sometimes referred to as the second foamed particles P) granulated by cutting with the next cutter blade 7a It comes into contact with the first foamed particles P. Then, the first foamed particles P and the second foamed particles P adhere to each other. Therefore, when the molten resin is sequentially cut by the plurality of cutter blades 7a, the foamed particles P are attached to each other in the foamed particle collision region 9a1.
  • the coating layer 9b is formed in the foamed particle collision region 9a1 where the foamed particles P immediately after being cut by the cutter 7 collide with each other.
  • the coating layer 9b prevents the foamed particles P from adhering to the foamed particle collision region 9a1 even when they are not completely solidified. Therefore, the foamed particles P which is cut by a certain cutter blade 7a (first foamed particles P) after the collision in the foamed particle bombardment region 9a1, without remaining in the foamed particle bombardment region 9a1, along trajectories Q 2 Moving.
  • the first foamed particles P are separated from the foamed particle collision region 9a1 before the foamed particles P (second foamed particles P) granulated by the next cutting by the cutter blade 7a collide with the foamed particle collision region 9a1.
  • the first foamed particles P and the second foamed particles P from adhering to each other.
  • the foamed particles P do not adhere to each other.
  • the coating layer 9b is formed only in the foamed particle collision region 9a1.
  • the coating layer 9b is not limited to the configuration shown in FIG. 2, and may be provided at least on the surface (foamed particle collision region 9a1) where the foamed particles P immediately after cutting collide.
  • the coating layer 9b may be formed in a region including the foamed particle collision region 9a1 and may be formed on the entire surface of the side wall surface 9a.
  • the coating layer 9b may be any material that can prevent the adhesion of the foamed particles P, and various known coating materials can be used.
  • the coating material is not particularly limited, and examples thereof include fluororesin, polyetheretherketone, and silicone rubber.
  • the foamed particle collision region 9a1 is a flat surface.
  • the surface formed by the foamed particle collision region 9a1 is not limited to a flat surface as long as it is a surface on which the foamed particles P can collide and can move from the collision point.
  • the position of the foamed particle collision region 9a1 in the cutter case 9 can be appropriately set according to the positional relationship between the die hole 6b of the die 6 and the cutter 7.
  • the manufacturing apparatus 10 shown in FIGS. 1 and 2 was a side-cut type apparatus.
  • the configuration of the manufacturing apparatus 10 according to the present embodiment is not particularly limited as long as it is a configuration applicable to the HC method.
  • the manufacturing apparatus 10 may be a center cut type apparatus.
  • the rotating shaft portion 7c of the cutter 7 is arranged so as to coincide with the central axis N of the die 6. Therefore, on the resin discharge surface 6a of the die 6, the die hole 6b is formed around the central axis N.
  • the foamed particles cut by the cutter 7 move in all directions with respect to the central axis N. Therefore, in this case, the foamed particle collision region 9a1 is formed on the entire side wall surface 9a of the cutter case 9.
  • the expansion ratio of the foamed particles P is 9 to 45 times. That is, the manufacturing apparatus 10 is suitable for manufacturing the foamed particles P having a foaming ratio of 9 to 45 times.
  • the granulation portion A has a configuration in which the molten resin is granulated by a hot-cut method instead of the UWC method. That is, after cutting the molten resin with the cutter 7, the foamed particles P are released not in water but in an atmospheric pressure atmosphere. Therefore, it is possible to produce foamed particles P having a high foaming ratio of 9 to 45 times as compared with the UWC method.
  • the foaming ratio of the foamed particles P is 9 to 45 times, more preferably 15 to 45 times.
  • the foaming ratio is as low as less than 9 times, the molten resin is difficult to solidify, and it is not possible to avoid mutual adhesion between the foamed particles.
  • the "foaming ratio” here does not mean the foaming ratio of the foamed particles P in the middle of foaming after being cut by the cutter 7, but the foaming ratio desired as a product.
  • the manufacturing apparatus 10 According to the manufacturing apparatus 10 according to the present embodiment, it is possible to prevent the foamed particles P from adhering to each other in the manufacturing process and to obtain the foamed particles P having a high foaming ratio.
  • ⁇ Raw material for foamed particles P> as a raw material for producing foamed particles P (hereinafter, may be simply referred to as “foamed particles”), in addition to a thermoplastic resin and carbon dioxide gas as a foaming agent, various additives are required as needed. Can be added. For example, flame retardants, heat stabilizers, radical generators, processing aids, weather resistance stabilizers, nucleating agents, foaming aids, antistatic agents, radiant heat transfer inhibitors, colorants and the like can be mentioned. .. These additives may be used alone or in combination of two or more.
  • thermoplastic resin used in the present embodiment is not particularly limited as long as it is a generally known thermoplastic resin having foamability. In foaming using carbon dioxide gas, the production method according to the present embodiment can be suitably applied to a thermoplastic resin having low carbon dioxide gas retention. From this point of view, the thermoplastic resin used in this embodiment is preferably a crystalline thermoplastic resin. Examples of such thermoplastic resins include polyolefin-based resins, polyester-based resins, polyphenylene ether-based resins, polyamide-based resins, polycarbonate-based resins, and mixtures thereof. The thermoplastic resin is more preferably a polyolefin-based resin or a polyester-based resin.
  • polyester resin examples include an aliphatic polyester resin, an aromatic polyester resin, and an aliphatic aromatic polyester resin.
  • Specific examples of the polyester resin include polyhydroxyalkanoate, polybutylene succinate (PBS), poly (butylene adipate-co-butylene terephthalate) (PBAT), polyethylene terephthalate (PET), and polybutylene terephthalate (PET). PBT) and the like.
  • the polyhydroxyalkanoates are poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), poly (3-hydroxybutyrate) (P3HB), and poly (3-hydroxybutyrate-co).
  • PHBV poly (3-hydroxybutyrate-co-4-hydroxybutyrate)
  • P3HB4HB poly (3-hydroxybutyrate-co-3-hydroxyoctanoate)
  • the polyolefin-based resin is not particularly limited, and polypropylene-based resin can be mentioned.
  • the polypropylene-based resin may be a general-purpose linear polypropylene-based resin, or may be a modified polypropylene-based resin having a branched structure or a high molecular weight component.
  • a linear polypropylene resin hereinafter, this resin may be referred to as a "raw polypropylene resin"
  • a linear polypropylene resin or a conjugated diene is used. Examples thereof include a method of melt-mixing the compound and the radical polymerization initiator.
  • the polypropylene-based resin is particularly preferably a resin having a branched structure, and the production method thereof is a modified polypropylene-based resin obtained by melt-mixing a linear polypropylene resin, a conjugated diene compound, and a radical polymerization initiator. Resins are preferable because they are easy to manufacture and are economically advantageous.
  • linear polypropylene-based resin examples include propylene homopolymers, block copolymers, and random copolymers, which are crystalline polymers.
  • the propylene copolymer a polymer containing 75% by weight or more of propylene is preferable because it retains the crystallinity, rigidity, chemical resistance and the like, which are the characteristics of polypropylene-based resins.
  • the copolymerizable ⁇ -olefins are ethylene, 1-butene, isobutene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3,4-dimethyl-1-butene.
  • Cyclic olefins such as -4-dodecene; 5-methylene-2-norbornene, 5-ethylidene-2-norbornene, 1,4-hexadiene, methyl-1,4-hexadiene, 7-methyl-1,6-octadiene Diene such as vinyl chloride, vinylidene chloride, acrylonitrile, vinyl acetate, acrylic acid, methacrylic acid, maleic acid, ethyl acrylate, butyl acrylate, methyl methacrylate, maleic anhydride, styrene, methylstyrene, vinyltoluene, divinylbenzen
  • a random copolymer is preferable from the viewpoint of moldability in in-mold molding of the obtained foamed particles and physical properties of the obtained molded product, and further, propylene / ethylene / 1-butene random copolymer or propylene / Ethylene random copolymers are preferred.
  • modified polypropylene-based resin that can be used in the present embodiment, a modified polypropylene-based resin obtained by melt-mixing the linear polypropylene-based resin with a conjugated diene compound and a radical polymerization initiator is preferable.
  • conjugated diene compound examples include butadiene, isoprene, 1,3-heptadiene, 2,3-dimethylbutadiene, 2,5-dimethyl-2,4-hexadiene and the like. These may be used alone or in combination of two or more. Of these, butadiene and isoprene are particularly preferable because they are inexpensive, easy to handle, and the reaction can proceed uniformly.
  • the amount of the conjugated diene compound added is preferably 0.01 parts by weight or more and 20 parts by weight or less, and 0.05 parts by weight or more and 5 parts by weight or less with respect to 100 parts by weight of the linear polypropylene resin. Is more preferable. If the amount of the conjugated diene compound added is less than 0.01 parts by weight, it may be difficult to obtain the modification effect, and if the amount of the conjugated diene compound added exceeds 20 parts by weight, the effect may be saturated and it may not be economical. is there.
  • Monopolymers copolymerizable with the conjugated diene compound such as vinyl chloride, vinylidene chloride, acrylonitrile, methacrylonitrile, acrylamide, methacrylicamide, vinyl acetate, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, acrylic acid.
  • Acrylic esters such as metal salts, metal methacrylates, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate; methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2 methacrylic acid -Methacrylic acid esters such as ethylhexyl and stearyl methacrylate; etc. may be used in combination.
  • radical polymerization initiator examples include peroxides and azo compounds, but polypropylene-based resins and initiators having the ability to extract hydrogen from the conjugated diene compound are preferable, and ketone peroxides, peroxyketals, and hydros are generally used. Examples thereof include organic peroxides such as peroxides, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, and peroxyesters. Of these, initiators having a particularly high hydrogen abstraction ability are preferable, and for example, 1,1-bis (t-butylperoxy) 3,3,5-trimethylcyclohexane and 1,1-bis (t-butylperoxy) cyclohexane are preferable.
  • N-Butyl 4,4-bis (t-butylperoxy) valerate, peroxyketal such as 2,2-bis (t-butylperoxy) butane; dicumyl peroxide, 2,5-dimethyl-2, 5-Di (t-butylperoxy) hexane, ⁇ , ⁇ '-bis (t-butylperoxy-m-isopropyl) benzene, t-butylcumyl peroxide, di-t-butyl peroxide, 2,5- Dialkyl peroxides such as dimethyl-2,5-di (t-butylperoxy) -3-hexine; diacyl peroxides such as benzoyl peroxide; t-butylperoxyoctate, t-butylperoxyisobutyrate, t-Butylperoxylaurate, t-butylperoxy3,5,5-trimethylhexanoate, t-butylperoxyis
  • the amount of the radical polymerization initiator added is preferably 0.01 parts by weight or more and 10 parts by weight or less, and 0.05 parts by weight or more and 4 parts by weight or less with respect to 100 parts by weight of the linear polypropylene resin. Is more preferable.
  • the amount of the radical polymerization initiator added is within the above range, efficient resin modification is possible. If the addition amount of the radical polymerization initiator is less than 0.01 parts by weight, it may be difficult to obtain the modification effect, and if the addition amount exceeds 10 parts by weight, the modification effect is saturated and it is not economical. In some cases.
  • a device for reacting a linear polypropylene resin, a conjugated diene compound and a radical polymerization initiator a roll, a conider, a Banbury mixer, a brabender; a kneader such as a single-screw extruder or a twin-screw extruder; a twin-screw surface.
  • Examples include a horizontal stirrer such as a renewer and a twin-screw multi-disc device; a vertical stirrer such as a double helical ribbon stirrer; Of these, it is preferable to use a kneader, and in particular, an extruder such as a single-screw extruder and a twin-screw extruder is preferable from the viewpoint of productivity.
  • the linear polypropylene resin, the conjugated diene compound and the radical polymerization initiator may be mixed and then melt-kneaded (stirred), or the polypropylene-based resin may be melt-kneaded (stirred) and then the conjugated diene compound or the radical initiator is added. It may be mixed at the same time or separately, collectively or divided.
  • the temperature of the kneader (stirring) is preferably 130 ° C. or higher and 300 ° C. or lower in that the linear polypropylene-based resin melts and does not thermally decompose.
  • the melt-kneading time is generally preferably 1 to 60 minutes.
  • the shape and size of the modified polypropylene resin thus obtained are not limited, and may be in the form of pellets.
  • the melting point of the polypropylene-based resin of the present embodiment is preferably 130 ° C. or higher and 155 ° C. or lower, more preferably 135 ° C. or higher and 153 ° C. or lower, and further preferably 140 ° C. or higher and 150 ° C. or lower. preferable.
  • the melting point of the polypropylene-based resin is within the above range, the dimensional stability and heat resistance of the foamed molded product in the mold are improved.
  • the pressure of the molding heating steam when the polypropylene-based resin foam particles are foam-molded in the mold becomes appropriate.
  • the melting point of the polypropylene resin is less than 130 ° C, the dimensional stability of the in-mold foam molded product tends to decrease or the heat resistance of the foamed molded product tends to be insufficient. If the melting point exceeds 155 ° C, the in-mold foaming tends to occur. The pressure of the molding heating steam during molding tends to increase.
  • the melting point of the polypropylene-based resin is measured by using a differential scanning calorimeter DSC [for example, DSC6200 type manufactured by Seiko Instruments Co., Ltd.] as follows. That is, 5 to 6 mg of a polypropylene-based resin is heated from 40 ° C. to 220 ° C. at a heating rate of 10 ° C./min to melt the resin, and then from 220 ° C. to 40 ° C. at a temperature decreasing rate of 10 ° C./min. After crystallization by lowering the temperature, the melting peak temperature in the DSC curve at the time of the second temperature rise when the temperature is raised again from 40 ° C. to 220 ° C. at a temperature rise rate of 10 ° C./min is defined as the melting point. ..
  • DSC differential scanning calorimeter
  • the foaming agent used in this embodiment is carbon dioxide gas.
  • Carbon dioxide is a preferred foaming agent from the viewpoint of safety during handling and simplification of required equipment specifications. Furthermore, if carbon dioxide gas is used as the foaming agent, a foam having a high foaming ratio can be easily obtained as compared with other inorganic foaming agents such as nitrogen and water.
  • the amount of the foaming agent added varies depending on the type of the thermoplastic resin and the target foaming ratio of the foamed particles, and may be appropriately adjusted. However, it is 1 part by weight or more and 20 parts by weight with respect to 100 parts by weight of the polypropylene resin. The following is preferable, and it is more preferably 1 part by weight or more and 10 parts by weight or less.
  • a bubble nucleating agent may be added for the purpose of controlling the bubble shape of the foamed particles.
  • the bubble nucleating agent include sodium bicarbonate-citric acid mixture, monosodium citrate salt, talc, calcium carbonate and the like, and these may be used alone or in combination of two or more.
  • the amount of the bubble nucleating agent added is not particularly limited, but is usually preferably 0.01 parts by weight or more and 5 parts by weight or less with respect to 100 parts by weight of the polypropylene-based resin.
  • a synthetic resin other than the polypropylene resin may be added as the base resin as long as the effect of the present invention is not impaired.
  • Synthetic resins other than polypropylene-based resins include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, linear ultra-low-density polyethylene, ethylene-vinyl acetate copolymer, and ethylene-acrylic.
  • Examples thereof include ethylene resins such as acid copolymers and ethylene-methacrylic acid copolymers; styrene resins such as polystyrene, styrene-maleic anhydride copolymers and styrene-ethylene copolymers; and the like.
  • stabilizers such as antioxidants, metal deactivators, phosphorus-based processing stabilizers, ultraviolet absorbers, ultraviolet stabilizers, fluorescent whitening agents, metal soaps, and antioxidative adsorbents.
  • additives such as cross-linking agents, chain transfer agents, nucleating agents, lubricants, plasticizers, fillers, reinforcing materials, pigments, dyes, flame retardants, antistatic agents and the like may be added.
  • the antacid adsorbent include magnesium oxide and hydrotalcite.
  • the addition of the colorant is not limited, and a natural color can be obtained without adding the colorant, or a desired color can be obtained by adding a colorant such as blue, red, and black. it can.
  • the colorant include perylene-based organic pigments, azo-based organic pigments, quinacridone-based organic pigments, phthalocyanine-based organic pigments, slene-based organic pigments, dioxazine-based organic pigments, isoindoline-based organic pigments, carbon black and the like.
  • foamed particles a method of pressurizing the inside of the polypropylene-based resin foamed particles with an inert gas and heating to increase the foaming ratio (for example, the method described in JP-A-10-237212) can also be used.
  • the weight of the foamed particles in the present embodiment is preferably 3 mg / particle or less, and more preferably 2 mg / particle or less, because it is easy to fill and expand to form a molded product having a beautiful appearance.
  • the lower limit is not particularly limited, but in consideration of productivity and the like, it is preferably 0.3 mg / particle or more.
  • the bubble diameter of the foamed particles in the present embodiment is 0.1 to 1 because the foamed particles expand to every corner of the mold in the foamed molding in the mold and the shrinkage of the obtained foamed molded product in the mold is small. It is preferably 0.0 mm, more preferably 0.15 to 0.7 mm.
  • the foamed molded product in the mold of the present embodiment is obtained by filling the foamed particles in a mold that can block but cannot seal the foamed particles and heating the foamed particles with steam.
  • the foamed particles are pressure-treated with an inorganic gas to impregnate the particles with the inorganic gas to apply a predetermined internal pressure to the particles.
  • the method of filling the mold and heating and fusing with steam or the like for example, Tokukousho No. 51-22951
  • Compressing the foamed particles with gas pressure and filling the mold to utilize the resilience of the particles for example, Tokusho No.
  • the method for producing the thermoplastic resin foamed particles according to the present embodiment is a method for producing the thermoplastic resin foamed particles, which is a melt-kneading step of melt-kneading the thermoplastic resin and carbon dioxide gas as a foaming agent, and a hot-cut method.
  • the hot-cut method comprises extruding the thermoplastic resin and the molten resin containing the foaming agent through the holes of the die, and the hot-cut method includes a granulation step of granulating the foamed particles of the thermoplastic resin. It is a step of cutting the extruded molten resin in air with a cutter and cooling the molten resin in air while foaming or after foaming.
  • a mixed mist of water and air is used in the granulation step.
  • the production method according to the present embodiment is not particularly limited as long as it is a method having such characteristics.
  • a manufacturing method using the manufacturing apparatus 10 described above can be mentioned.
  • a method for producing thermoplastic resin foamed particles using the production apparatus 10 will be described with reference to FIGS. 1 and 2.
  • the thermoplastic resin is charged into the extruder 1 from the feeder 2, and for example, a polypropylene-based resin is melted at a barrel temperature of 200 ° C.
  • the foaming agent is added to the extruder 1 from the foaming agent supply unit 3 (melt kneading step).
  • additives other than the above-mentioned thermoplastic resin may be added to the extruder 1.
  • the extruder 1 may be provided with an addition port different from the feeder 2 for charging the thermoplastic resin, and another additive may be charged into the extruder 1 from this addition port.
  • the molten resin containing the thermoplastic resin and the foaming agent is melt-kneaded in the extruder 1, and then the molten resin is sent from the transport unit 4 to the cooling unit 5. Then, after the molten resin is cooled to a desired resin temperature by the cooling unit 5, the molten resin is extruded through the die 6.
  • the foamed particles P are granulated by a hot-cut method (granulation step). In this hot-cut method, the molten resin is extruded through the die hole 6b of the die 6, and the molten resin extruded from the die hole 6b of the die 6 is cut in air with a cutter 7 to foam the molten resin.
  • the cutter 7 is driven to rotate the cutter blade 7a around the rotating shaft portion 7c. Then, the molten resin extruded from the die 6 is cut by the cutter 7. At this time, air or water is ejected from the cutter 7. For example, after cutting with the cutter 7, air is discharged from the air discharge port 7b so that the molten resin can be easily separated from the cutter blade 7a.
  • the linear velocity of air is preferably 25 m / sec or more. When the linear velocity of the air is less than 25 m / sec, the degree of separation of the thermoplastic resin foam particles from the cutter blade 7a becomes worse, and the thermoplastic resin foam particles tend to adhere to each other.
  • the pressure of the molten resin of the extruder 1 is kept constant by the transport unit 4.
  • the pressure of the molten resin of the extruder 1 may be maintained so that the foaming agent does not vaporize.
  • the foaming agent is carbon dioxide gas, it can be set to 10 MPa.
  • the temperature of the molten resin immediately before being extruded from the die 6 is cooled to a desired resin temperature by the cooling unit 5.
  • the temperature of the molten resin immediately before being extruded from the die 6 can be, for example, 142 ° C. for a polypropylene-based resin.
  • the mist nozzle 8 is used to spray cooling water onto the molten resin cut by the cutter 7.
  • a mixed mist M of water and air is ejected toward the die hole 6b of the die 6, and the water spray flow rate by the mist nozzle 8 is 1 L / h to 9 L / h per nozzle. Therefore, mist adheres to the surface of the foamed particles P immediately after cutting. Since the mist adhering to the surface of the foamed particles P is vaporized to promote the surface solidification of the foamed particles P, the foamed particles P do not adhere to each other.
  • the water spray flow rate is 1 L / h to 9 L / h per nozzle, preferably 3 L / h to 9 L / h, and more preferably 3 L / h to 6 L / h. If the spray flow rate is smaller than 1 L / h, the foamed particles will be insufficiently cooled, and the foamed particles will easily adhere to each other. Further, if the spray flow rate is larger than 9 L / h, the die 6 is excessively cooled, and the die holes 6b are easily blocked by the molten resin.
  • the average spray particle size of water is preferably 40 ⁇ m or less, and more preferably 35 ⁇ m or less. If the average spray particle size is larger than 40 ⁇ m, the die 6 is likely to be cooled, and the die holes 6b are likely to be clogged with the molten resin. For this reason, the cooling efficiency of the foamed particles deteriorates, so that the foamed particles tend to adhere to each other.
  • the foamed particles P are released into the cutter case 9 in an atmospheric pressure atmosphere instead of in water. Therefore, it is possible to produce foamed particles P having a high foaming ratio of 9 to 45 times as compared with the UWC method.
  • the manufacturing method according to the present embodiment further includes a recovery step of recovering the thermoplastic resin foamed particles formed from the molten resin cut by the cutter, and in the recovery step, a non-adhesive coating treatment is performed. It is preferable to collide the surface with the thermoplastic resin foam particles immediately after cutting.
  • the foamed particles P formed from the molten resin cut by the cutter 7 are recovered in the cutter case 9. Then, in the recovery step, the foamed particles P immediately after cutting are made to collide with the coating layer 9b of the foamed particle collision region 9a1.
  • the coating layer 9b is a layer formed as a result of applying a non-adhesive coating treatment to the foamed particle collision region 9a1. As a result, it is possible to further prevent the foamed particles P from adhering to each other.
  • the production method according to the first aspect of the present invention is the method for producing the thermoplastic resin foamed particles, which is a melt-kneading step of melt-kneading the thermoplastic resin and carbon dioxide gas as a foaming agent, and hot-cutting.
  • the hot-cut method includes a granulation step of granulating thermoplastic resin foamed particles (foamed particles P) by a method, and the hot-cut method involves the thermoplastic resin and the foaming agent through a hole (die hole 6b) of the die 6.
  • the molten resin containing the above is extruded, and the molten resin extruded from the hole (die hole 6b) of the die 6 is cut in the air with a cutter 7, and the molten resin is foamed or foamed into the air.
  • the granulation step includes a step of ejecting a mixed mist M of water and air toward a hole (die hole 6b) of the die 6, and a nozzle (mist nozzle 8) is provided in the step.
  • the spray flow rate of water is 1 L / h to 9 L / h per nozzle.
  • the production method according to the second aspect of the present invention further includes, in the first aspect, a recovery step of recovering the thermoplastic resin foamed particles (foamed particles P) formed from the molten resin cut by the cutter 7.
  • the recovery step includes a step of colliding the thermoplastic resin foamed particles immediately after cutting with the surface (coating layer 9b) subjected to the non-adhesive coating treatment.
  • the manufacturing method according to the third aspect of the present invention includes, in the first or second aspect, the step of discharging air or water from the cutter 7 in the granulation step.
  • the linear velocity of the air discharged from the cutter 7 is 25 m / sec or more in the third aspect.
  • the average spray particle size of the mixed mist M is 40 ⁇ m or less in any one of the first to fourth aspects.
  • the foaming ratio of the thermoplastic resin foamed particles (foamed particles P) is 9 to 45 times.
  • the foaming ratio of the thermoplastic resin foamed particles (foamed particles P) is 15 to 45 times.
  • thermoplastic resin foamed particles are crystalline thermoplastic resins.
  • the manufacturing apparatus 10 is the thermoplastic resin foamed particle manufacturing apparatus 10, which is an extruder 1 that melts and kneads the thermoplastic resin and carbon dioxide gas as a foaming agent, and extrudes from the extruder 1.
  • a die 6 having a hole (die hole 6b) through which the thermoplastic resin and the molten resin containing the foaming agent pass, and the molten resin passing through the hole (die hole 6b) of the die 6 are passed through the hole (die hole 6b) in the air.
  • It has a cutter 7 for cutting, has a granulation portion A for granulating thermoplastic resin foam particles (foam particles P) by a hot cut method, and is provided with at least one spray port 8a for spraying water.
  • the spray port 8a is configured to be installed toward the hole (die hole 6b) of the die 6.
  • the manufacturing apparatus 10 is the ninth aspect.
  • the cutter 7 is configured to include a discharge port (air discharge port 7b) for discharging air or water.
  • the manufacturing apparatus 10 further collects the thermoplastic resin foamed particles (foamed particles P) formed from the molten resin cut by the cutter 7 in the 9th or 10th aspect (the collecting unit (foaming particles P).
  • a cutter case 9) is provided, and a non-adhesive coating treatment is applied to at least the surface (foamed particle collision region 9a1) where the thermoplastic resin foamed particles (foamed particles P) immediately after cutting collide with the collecting portion. is there.
  • the collecting part is a cutter case 9 for accommodating the cutter 7, and the non-adhesive coating treatment is applied to the side wall surface 9a of the cutter case 9. It is a configuration that is.
  • Example 1 The foamed particles P were produced using the production apparatus 10 shown in FIGS. 1 and 2 according to the following production conditions.
  • the foaming ratio of the produced foamed particles P was 23.9 times.
  • the mutual adhesion rate between the foamed particles was 0%.
  • Example 1 The foamed particles P were produced in the same manner as in ⁇ Production Conditions> of Example 1 except that the mixed mist M was not sprayed onto the die 6. As a result, the foaming ratio of the produced foamed particles P was 21.2 times. The mutual adhesion rate between the foamed particles was 6%.
  • Extruder 2 Feeder 3 Foaming agent (carbon dioxide) supply unit 4 Transport unit 5 Cooling unit 6 Die 6a Resin discharge surface 6b Die hole (die hole) 7 Cutter 7b Air discharge port 8 Mist nozzle 8a Spray port 9 Cutter case (collection part) 9a1 Foam particle collision region (surface on which thermoplastic resin foam particles collide) 9b coating layer (non-adhesive coating) 9c Discharge port 10 Manufacturing equipment A Granulation part M Mixed mist P Foamed particles

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
PCT/JP2020/043448 2019-11-27 2020-11-20 熱可塑性樹脂発泡粒子の製造方法および製造装置 Ceased WO2021106795A1 (ja)

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EP20893499.2A EP4067032A4 (en) 2019-11-27 2020-11-20 MANUFACTURING DEVICE AND MANUFACTURING METHOD FOR THERMOPLASTIC RESIN FOAM PARTICLES
JP2021561383A JP7628963B2 (ja) 2019-11-27 2020-11-20 熱可塑性樹脂発泡粒子の製造方法および製造装置

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024218053A1 (de) 2023-04-19 2024-10-24 Covestro Deutschland Ag Verfahren zur herstellung von schaumteilchen aus einer polycarbonat-formulierung

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5122951A (ja) 1974-08-16 1976-02-24 Yoshio Ihara Eaaenjin
JPS5333996A (en) 1976-09-10 1978-03-30 Central Glass Co Ltd Production of ultrafine grains of silica
JPH0671128A (ja) 1992-08-27 1994-03-15 Oji Kenzai Kogyo Kk ハニカム構造体のフイルター
JPH06170839A (ja) 1992-09-03 1994-06-21 Plast Kogaku Kenkyusho:Kk ホットカットペレタイザー
JPH10237212A (ja) 1997-02-21 1998-09-08 Huels Ag 発泡したポリオレフィン粒状物を更に発泡する方法
JP2001205285A (ja) * 2000-01-28 2001-07-31 Takeda Chem Ind Ltd 水処理用担体、水処理用担体の製造方法および水処理用装置
JP2005512851A (ja) * 2001-12-20 2005-05-12 ポリメーリ　エウローパ　ソシエタ　ペル　アチオニ 発泡性熱可塑性ポリマーの顆粒を製造するための方法および装置
WO2009104671A1 (ja) 2008-02-20 2009-08-27 積水化成品工業株式会社 造粒用ダイス、造粒装置、及び発泡性熱可塑性樹脂粒子の製造方法
JP2011202077A (ja) 2010-03-26 2011-10-13 Sekisui Plastics Co Ltd 熱可塑性樹脂予備発泡粒子とその製造方法、熱可塑性樹脂発泡成形体

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2328019B2 (de) * 1973-06-01 1976-03-04 Werner & Pfleiderer, 7000 Stuttgart Granuliervorrichtung fuer kunststoffe
DE2455757A1 (de) * 1974-11-26 1976-06-10 Basf Ag Verfahren und vorrichtung zum granulieren thermoplastischer massen
JPH1076520A (ja) * 1996-09-04 1998-03-24 Kobe Steel Ltd 水中カット造粒装置のスタート前制御方法及び水中カット造粒装置
ITMI20071005A1 (it) * 2007-05-18 2008-11-19 Polimeri Europa Spa Procedimento per la preparazione di granuli a base di polimeri termoplastici espandibili e relativo prodotto
DE102013020316A1 (de) * 2013-12-05 2015-06-11 Automatik Plastics Machinery Gmbh Verfahren zur Herstellung von Granulatkörnern aus einem Schmelzematerial

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5122951A (ja) 1974-08-16 1976-02-24 Yoshio Ihara Eaaenjin
JPS5333996A (en) 1976-09-10 1978-03-30 Central Glass Co Ltd Production of ultrafine grains of silica
JPH0671128A (ja) 1992-08-27 1994-03-15 Oji Kenzai Kogyo Kk ハニカム構造体のフイルター
JPH06170839A (ja) 1992-09-03 1994-06-21 Plast Kogaku Kenkyusho:Kk ホットカットペレタイザー
JPH10237212A (ja) 1997-02-21 1998-09-08 Huels Ag 発泡したポリオレフィン粒状物を更に発泡する方法
JP2001205285A (ja) * 2000-01-28 2001-07-31 Takeda Chem Ind Ltd 水処理用担体、水処理用担体の製造方法および水処理用装置
JP2005512851A (ja) * 2001-12-20 2005-05-12 ポリメーリ　エウローパ　ソシエタ　ペル　アチオニ 発泡性熱可塑性ポリマーの顆粒を製造するための方法および装置
WO2009104671A1 (ja) 2008-02-20 2009-08-27 積水化成品工業株式会社 造粒用ダイス、造粒装置、及び発泡性熱可塑性樹脂粒子の製造方法
JP2011202077A (ja) 2010-03-26 2011-10-13 Sekisui Plastics Co Ltd 熱可塑性樹脂予備発泡粒子とその製造方法、熱可塑性樹脂発泡成形体

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4067032A4

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024218053A1 (de) 2023-04-19 2024-10-24 Covestro Deutschland Ag Verfahren zur herstellung von schaumteilchen aus einer polycarbonat-formulierung

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