WO2000044549A1 - Procede d'extrusion-soufflage et son extrudeuse a vis - Google Patents

Procede d'extrusion-soufflage et son extrudeuse a vis Download PDF

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Publication number
WO2000044549A1
WO2000044549A1 PCT/JP2000/000313 JP0000313W WO0044549A1 WO 2000044549 A1 WO2000044549 A1 WO 2000044549A1 JP 0000313 W JP0000313 W JP 0000313W WO 0044549 A1 WO0044549 A1 WO 0044549A1
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WO
WIPO (PCT)
Prior art keywords
polymer
screw
polymer composition
cylinder
supply port
Prior art date
Application number
PCT/JP2000/000313
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English (en)
Japanese (ja)
Other versions
WO2000044549A8 (fr
Inventor
Hirotoshi Mizota
Shigeaki Sasaki
Masahiro Taniguchi
Original Assignee
Mitsubishi Rayon Co., Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP01767999A external-priority patent/JP3760059B2/ja
Priority claimed from JP11026460A external-priority patent/JP2000226410A/ja
Application filed by Mitsubishi Rayon Co., Ltd. filed Critical Mitsubishi Rayon Co., Ltd.
Publication of WO2000044549A1 publication Critical patent/WO2000044549A1/fr
Publication of WO2000044549A8 publication Critical patent/WO2000044549A8/fr

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Classifications

    • 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
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/50—Details of extruders
    • B29C48/76—Venting, drying means; Degassing means
    • B29C48/765—Venting, drying means; Degassing means in the extruder apparatus
    • B29C48/766—Venting, drying means; Degassing means in the extruder apparatus in screw extruders
    • B29C48/767—Venting, drying means; Degassing means in the extruder apparatus in screw extruders through a degassing opening of a barrel
    • 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
    • B29B7/84—Venting or degassing ; Removing liquids, e.g. by evaporating components
    • B29B7/845—Venting, degassing or removing evaporated components in devices with rotary stirrers
    • 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
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/50—Details of extruders
    • B29C48/76—Venting, drying means; Degassing means
    • B29C48/762—Vapour stripping
    • 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

Definitions

  • the present invention relates to a polymer obtained by a solution polymerization method or a bulk polymerization method, and a polymer composition containing a volatile component such as an unreacted monomer, a solvent, and a volatile by-product.
  • the present invention relates to a devolatilizing extrusion method and a screw type devolatilizing extruder for separating a polymer to obtain a polymer.
  • methacrylic polymers have been spotlighted as optical materials because of their excellent transparency. To maximize this transparency, it is necessary to thoroughly eliminate contaminants (by-products) generated during the manufacturing process. Manufacture of products from polymers containing contaminants can result in defects. For example, when a plastic optical fiber (hereinafter sometimes abbreviated as an optical fiber) is manufactured, a portion where the transmission performance is locally reduced in the length direction of the optical fiber occurs. Also, when disks are manufactured, they appear as surface defects after molding.
  • polymerization methods are disclosed in Japanese Patent Publication No. Sho 52-32665, Japanese Patent Publication No. Hei 7-72213, and Japanese Patent Laid-Open Publication No. Hei 3-111408.
  • a continuous bulk polymerization method, a continuous solution polymerization method, etc., which have a low possibility of contamination by contaminants as described above, are suitable.
  • the product obtained by such a polymerization method is, in addition to the polymer, It is a polymer composition containing a volatile component such as a monomer, a solvent, and a volatile by-product generated in the polymerization process.
  • this polymer composition Since the polymer content of this polymer composition is generally 40 to 70% by weight, a large amount of volatile components of 60 to 30% by weight is devolatilized from the polymer composition and separated and removed. Must. Also, in the devolatilization process, it is necessary to prevent the generation of contaminants as much as possible. If contaminants are generated, it is necessary to prevent contaminants from being mixed into the obtained polymer.
  • the screw-type devolatilizing extruder is generally provided with a cylinder having a polymer composition supply port, a polymer outlet, and a volatile component outlet (bent), and is rotatably disposed in the cylinder. It has a screw.
  • this extruder feeds the polymer composition supplied from the polymer composition supply port to the polymer outlet by rotation of the screw, and outputs the volatile components in the polymer composition to the volatile components. It is designed to be discharged from the mouth.
  • Japanese Patent Publication No. 52-175555 describes that a polymer composition heated to 210-270 ° C. while being pressurized to 20 kg / cm 2 or more contains 5 kg / cm 2. 0 Fluid is flushed into the cylinder under reduced pressure from atmospheric pressure to atmospheric pressure through the fine pores or narrow gaps of the nozzle provided at the polymer composition supply port, and directly blown onto the screw A method for doing so is disclosed.
  • the polymer composition When the polymer composition is supplied under such conditions, the polymer composition rapidly foams in the cylinder and is separated into a volatile component and a polymer, and most of the volatile component is separated and recovered. Can be.
  • the polymer composition since the polymer composition is supplied at high speed, the polymer composition rapidly foams in the cylinder, and the flow path of the volatile gas is temporarily blocked by the polymer. And wanted to venture up at the volatile component outlet. When venting up, the removal amount of volatile components becomes unstable or the removal amount becomes insufficient. In addition, the quality of the obtained polymer is not stable, which may cause defects in products manufactured from the polymer.
  • the degree of freedom in setting the operating conditions must be extremely narrow in order to suppress the increase in the number of operating conditions, and in many cases, it is difficult to set industrially advantageous conditions for mass processing.
  • a volatile component outlet is provided on the screw driving side (upstream side) of the polymer composition supply port in the length direction of the cylinder, and the polymer composition supply port is connected to the volatile component outlet.
  • Prepare a screw-type devolatilizing extruder that ensures the axial distance is 3D (D : screw diameter) or more.
  • the polymer outlet is provided on the opposite side of the volatile component outlet in the length direction of the cylinder.
  • the polymer composition containing the volatile component is heated in advance, and a part of the volatile component is vaporized, and in a gas-liquid mixed flow or a gas-liquid-solid mixed flow state. Supply within.
  • the volatile component separated from the polymer is passed through the space formed by the cylinder and the screw at a flow rate of 50 m / sec or less, and is discharged from the volatile component outlet.
  • Japanese Patent Application Laid-Open No. 3-49925 discloses that the distance between the polymer composition supply port and the volatile component outlet is set to be large by this method, and the volatile component is extracted at a specific speed. It states that the problem of venting up can be almost eliminated.
  • the devolatilizing extruder used for the production of methacrylic polymers with excellent light transmission properties suitable for plastic optical fibers and the like includes the devolatilizing extruder used for the production of general molding materials. In comparison with, it is necessary to use a material with extremely excellent corrosion resistance.
  • JP-A-61-275705 discloses that the nickel content is 10% by weight.
  • a devolatilizing extruder using a screw and a cylinder made of an alloy having a ratio of / 0 or more is disclosed.
  • JP-A-2-49005 discloses that the chromium content is 10 to 25% by weight, the nickel content is 2% by weight or less, and the hardness is Rockell C scale. Discloses a devolatilizing extruder using a screw and a cylinder made of an alloy having a diameter of 40 or more. When an alloy having a chromium content exceeding 25% by weight is used, chromium reacts with a mercaptan compound derived from a raw material of a methacrylic polymer in an oxygen atmosphere to form chromium sulfide. It is described that a compound is precipitated to significantly deteriorate the light-transmitting performance of the obtained polymer.
  • the polymer between the polymer composition supply port and the polymer outlet is always forced out of the polymer outlet, but the space on the opposite side of the polymer outlet, that is, However, the polymer tends to stay on the side of the drive section (shaft seal bearing section) that supports the screw, and the stay causes a part of the polymer to thermally degrade and produce by-products.
  • this portion is not filled with the polymer. Then, the cylinder and the screw come into direct contact with each other, forming a metal touch, increasing the amount of abrasion powder generated by galling, and the abrasion powder is mixed into the polymer.
  • both ends of a screw in the axial direction are supported in a cylinder, and near the support points at both ends of the screw, respectively.
  • a method using a screw-type devolatilizing extruder provided with a coalescing discharge port and provided with a polymer composition supply port and a volatile component outlet at an intermediate portion in the length direction of the cylinder is disclosed.
  • the polymer is sent and discharged from the middle part to both ends in the length direction of the cylinder, so that the polymer does not easily stay in the cylinder, and the heat of the polymer is reduced. Deterioration can be prevented. For this reason, a polymer with little contaminants can be obtained.
  • the present invention has been made in view of the above circumstances, and has a high degree of freedom in setting production conditions, and a devolatilization extrusion method and a devolatilization extrusion of a polymer composition containing a volatile component capable of setting industrially advantageous conditions.
  • the task is to provide a device.
  • the present invention solves the above-mentioned problems of the conventional devolatilizing extrusion apparatus used in producing a methacrylic polymer suitable for plastic optical fibers and the like, and has improved corrosion resistance and abrasion resistance. More improved devolatilization
  • An object of the present invention is to provide a method for devolatilizing and extruding a methacrylic polymer composition to obtain a methacrylic polymer having excellent translucency using an extruder.
  • the present invention proposes the following solutions.
  • the first invention of the present application is directed to a cylinder having a polymer composition supply port, a polymer outlet, and a volatile component outlet, and a screw supported by the cylinder in a rotating manner. And supplying a polymer composition containing a polymer and a volatile component from the polymer composition supply port to the screw-type devolatilizing extruder having the following formula: In a devolatilization extrusion method of a polymer composition for obtaining the polymer from a polymer outlet,
  • a devolatilization extrusion method wherein a nozzle opening area of the polymer composition supply port satisfies the following expression (1).
  • the second invention is a cylinder provided with a polymer composition supply port, a polymer outlet, and a volatile component outlet, and a screw rotatably supported in the cylinder. And supplying the polymer composition to a screw-type devolatilizing extruder having A polymer composition containing a polymer and a volatile component is supplied from a mouth, the volatile component is discharged from the volatile component outlet, and the devolatilization and extrusion of the polymer composition is performed to obtain the polymer from the polymer outlet.
  • a volatile component outlet is provided on the upstream side of the polymer composition supply port in the length direction of the cylinder, and a polymer outlet is provided on the downstream side of the polymer composition supply port, and all of the polymer is provided.
  • a devolatilization extrusion method characterized by sending most of the polymer toward the downstream side and sending the remaining polymer that has moved upstream from the polymer composition supply port toward the upstream side.
  • a volatile component outlet is provided upstream of the polymer composition supply port in the length direction of the cylinder, and a polymer outlet is provided downstream of the polymer composition supply port,
  • the screw of the screw is reversed in the middle so that the polymer is sent in both directions of the volatile component outlet and the polymer outlet. It is preferable to use an output device.
  • the distance between the inner edge of the opening of the polymer composition supply port on the volatile component outlet side and the switching position where the screw direction of the screw is reversed is set.
  • X where D is the screw diameter, and Y is the opening diameter of the polymer composition supply port in the longitudinal direction of the screw, and the inner edge is the origin, and positive coordinates are on the volatile component outlet side.
  • D is the screw diameter
  • Y is the opening diameter of the polymer composition supply port in the longitudinal direction of the screw
  • the inner edge is the origin
  • positive coordinates are on the volatile component outlet side.
  • the polymer composition heated to 150 ° C. to 270 ° C. under pressure to prevent foaming is introduced into the polymer composition supply port.
  • the pressure is preferably supplied into a cylinder at a pressure of 1 O mm Hg to atmospheric pressure.
  • a cylinder and a screw rotatably supported in the cylinder are provided.
  • a devolatilizing extrusion method characterized by using a screw-type devolatilizing extruder in which the surface of the screw is covered with a mouth or titanium nitride.
  • At least one of the screw flute and the inner surface of the cylinder of the screw-type devolatilizing extruder has a copart content of 50 to 95% by weight and a copper content of 5%. ⁇ 35 wt%, iron content is 0-5 wt%, and coated with a cobalt-based alloy having a Rockwell C scale hardness (hereinafter simply referred to as “hardness” as appropriate) of 40 or more. It is preferred that it be done.
  • FIG. 1 is a partial side sectional view showing an example of a screw-type devolatilizing extrusion apparatus used in the first invention of the present application.
  • FIG. 2 (a) is a schematic diagram showing an example of the refractive index distribution shape of the core-sheath type optical fiber.
  • FIG. 2 (b) is a schematic diagram showing an example of the refractive index distribution shape of the gradient index optical fiber.
  • FIG. 3 (a) is a partial cross-sectional view showing an example of a screw-type devolatilizing extrusion device used in the second invention of the present application, and
  • FIG. 3 (b) is a sectional view of FIG.
  • FIG. 2 is a partial side sectional view showing a main part of a).
  • the present invention relates to, for example, a thermopolymer containing a polymer obtained by solution polymerization or bulk polymerization, and a volatile component such as an unreacted monomer, a solvent (an inert solvent), and a volatile by-product generated in the polymerization process. It can be applied to devolatilization and extrusion of a plastic polymer composition.
  • the polymer constituting this composition is not particularly limited as long as it is obtained as a polymer composition containing a volatile component after the polymerization step as described above.
  • Derivatives eg alkyl
  • Examples include homopolymers of vinyl compounds such as (meth) acrylates and styrene, and copolymers mainly containing these vinyl compounds.
  • a homopolymer of methyl methacrylate or a copolymer mainly containing methyl methacrylate is preferred.
  • the copolymer mainly composed of methyl methacrylate is composed of 50% by weight or more of methyl methacrylate units and 50% by weight or less of other monomer units copolymerizable with methyl methacrylate.
  • Is a copolymer of Copolymers having a methyl methacrylate unit content of at least 80% by weight are more preferred.
  • Other units that can be copolymerized include methyl acrylate, fluoroalkyl methacrylate, benzyl methacrylate and other non-methyl methacrylates.
  • volatile components contained in the polymer composition include, in the case of the bulk polymerization method, unreacted monomers, volatile by-products, residual chain transfer agents, And volatile components such as impurities in monomers such as organic acidic compounds.
  • a solvent and the like are further included.
  • the polymer content of the polymer composition is not particularly limited, but is desirably 30% by weight or more, preferably 30 to 80% by weight, and more preferably 40 to 75% by weight. If the polymer content is too small, it is industrially disadvantageous because the volatilization amount is large and the energy burden is large. If the amount is too large, depending on the characteristics of the polymer and the operating conditions, the viscosity of the polymer composition will increase greatly, and it may be difficult to smoothly separate the volatile component from the polymer.
  • FIG. 1 shows an example of a screw-type devolatilizing extruder (hereinafter abbreviated as a devolatilizing extruder) used in the first invention of the present application.
  • a substantially cylindrical screw 2 is provided in the hollow part 1a of the cylindrical cylinder 1.
  • One end of the screw 2 is rotatably supported by a shaft seal bearing portion 2a as a driving portion.
  • a spiral groove 2b is provided on a side surface of the screw 2 and is screwed.
  • the devolatilizing extrusion device may be a single-screw type provided with one screw or a biaxial type provided with two screws.
  • a polymer composition supply port 3 having a nozzle 3a that opens into the hollow portion 1a of the cylinder 1 is provided on the side surface of the cylinder 1.
  • the nozzle 3a may have various shapes such as a cylinder, a rectangular slit, a perforated hole, and a multi-slit, for example. In order to secure and supply at a uniform speed, it is preferable to use a rectangular slit or a multi-strip slit.
  • a valve 3c is provided in the middle of the nozzle 3a. Since this valve 3c is present, as described later, by controlling the pressure in front of the valve 3c (above the valve 3c in FIG. 1), foaming of the polymer composition is suppressed. Thus, the polymer composition can be stably supplied into the cylinder 1.
  • the valve 3c is not particularly limited as long as it has a pressure regulating function. Specifically, a needle valve or the like is preferable. Further, in order to facilitate operation management, it is more preferable to use one having an automatic pressure regulation function.
  • a polymer outlet 4 is provided on the tip side of the screw 2 of the cylinder 1.
  • a supply-port-side volatile component outlet (hereinafter, referred to as a rear vent) 5 is provided between the shaft seal bearing portion 2 a and the polymer composition supply port 3 on the side surface of the cylinder 1,
  • An outlet-side volatile component outlet (hereinafter, referred to as a forevent) 6 is provided between the polymer composition supply port 3 and the polymer outlet 4.
  • Forevent 6 is not always necessary if the volatile components can be sufficiently discharged by rear vent 5. Further, one or more forevents 6 can be provided as necessary depending on the composition of the polymer composition and the like.
  • the operating area is set by setting the opening area S of the opening of the polymer composition supply port 3, that is, the opening 3b of the nozzle 3a, so as to satisfy the above-mentioned formula (1). .
  • the screw diameter D and the screw groove depth H in equation (1) are shown in FIG.
  • the screw diameter D is the diameter of the screw at the position of the polymer composition supply port 3.
  • the screw groove depth H is the screw groove depth at the position of the polymer composition supply port 3.
  • the opening area S is set so as to satisfy the following equation (2), and the operating conditions are set.
  • the polymer is exited from the polymer by the removal of the screw 2 in the gap between the inner wall of the cylinder 1 and the outer surface of the screw 2.
  • the gap is not blocked by the polymer, the flow path of the volatile gas is secured, and the volatile component is efficiently discharged from the reactor (5).
  • the discharge speed of the polymer becomes relatively faster than the screwing speed of the screw 2, and the inside of the gap becomes polymer.
  • the flow path of volatile gas toward rear vent 5 Insufficient and volatile components are difficult to discharge.
  • the polymer is entrained in the volatile gas going to the rear vent 5, and the polymer easily swells on the rear vent 5 side, and the rear vent 5 is blocked, thereby causing a vent up. .
  • the opening area S is larger than the right side of equation S (1), the polymer composition in the opening 3b in the nozzle 3a excessively foams, and a large airway is formed in the foam. In addition, a uniform foam state is not obtained, and a space is formed only by the foam part and the volatile component. Since the size of this space constantly fluctuates, the supply amount of the polymer into the cylinder 11 from the polymer composition supply port 3 fluctuates, and the supply amount of the polymer becomes uneven, resulting in surging. Cause.
  • the polymer composition is preliminarily heated to 150 ° C. to 270 ° C., preferably 170 ° C. to 250 ° C., and supplied to the nozzle 3a. If the preheating temperature is too low, sufficient separation of volatile components may be difficult. If it is too high, dimer production will increase and the content of pollutants will increase. In general, by-products such as dimers have a higher boiling point than monomers and are difficult to separate, which causes a decrease in the transparency of the methacrylic polymer, that is, a contaminant.
  • the polymer composition it is preferable to pressurize the polymer composition to prevent foaming of the polymer composition.
  • the foamed polymer composition is heated in the pipe portion on the front side of the knob 3c, the polymer composition stays in the pipe and causes coloring.
  • the method for heating and pressurizing the polymer composition is not particularly limited, and well-known methods can be applied. For example, it is preferable to transfer the polymer composition while heating and pressurizing it in a pipe with a jacket and supply it to the nozzle 3a.
  • the pressure is maintained by adjusting the opening of the valve 3c to prevent foaming of the polymer composition before the valve 3c. Then, the polymer composition is continuously supplied from the opening 3b of the nozzle 3a into the hollow portion 1a while passing through the valve 3c and foaming appropriately.
  • the polymer composition can be stably supplied into the hollow portion 1a of the cylinder 1, and the hollow portion 1a
  • the polymer composition can be foamed appropriately at a stretch within 1a, and volatile components can be efficiently removed.
  • the pressure in the hollow portion 1a of the cylinder 1 is reduced to a pressure of 1 OT orr to atmospheric pressure, preferably 50 torr to atmospheric pressure, and more preferably 50 torr to less than atmospheric pressure. Adjust to the state.
  • the polymer composition supplied into the hollow portion 1a of the cylinder 1 foams at once due to the difference between the pressure before passing through the valve 3c and the pressure inside the hollow portion la after passing through. While colliding with screw 2, causing volatile components and heavy Coalescence separates and some of the volatile components are recovered from Liavent 5. On the other hand, the polymer is sent to the polymer outlet 4 by the rotation of the screw 2. At this time, the remaining volatile components are discharged from the rear vent 5 and the fore vent 6, and a polymer is obtained from the polymer outlet 4.
  • the polymer composition supply port 3 is connected to the hollow part la of the cylinder! _. Since the speed of the gas-liquid mixed stream composed of the supplied polymer composition and the speed of screw removal are maintained at optimal values. Efficient removal of volatile components and prevention of venting be able to. Therefore, the degree of freedom in operating conditions is high, and it is suitable for industrially advantageous large-scale treatment.
  • the distance between the polymer composition supply port 3 and the reactor 5 does not need to be long, and for example, it is sufficient if the screw diameter D is about one time.
  • the length of the cylinder 1 can be shortened, the size of the apparatus can be reduced, and the amount of the polymer remaining in the cylinder 1 can be reduced, so that the side effect due to thermal degradation of the polymer can be reduced. Biological production can be prevented.
  • the cylinder 1 and the screw 2 are less likely to be galled, and the mixing of wear powder can be suppressed.
  • devolatilization and extrusion of a methacrylic polymer can produce a large amount of a polymer having excellent transparency compared to a conventional apparatus of the same size, which is industrially advantageous.
  • the methacrylic polymer having excellent transparency thus obtained is suitable, for example, for an optical fiber core. This is because, in an optical fiber, the better the transparency of the core, the more the transmission characteristics of the optical fiber can be improved.
  • the stable removal of volatile components and suppression of contaminant contamination can suppress the phenomenon in which transmission loss is locally reduced in the length direction of the optical fiber.
  • the structure of the optical fiber using the polymer of the present invention is not particularly limited, and a core 10 and a sheath 11 as shown in FIG. 2 (a) are concentrically laminated.
  • the core-sheath type optical fiber whose refractive index changes abruptly at the interface, from the center 10 of the core as shown in Fig. 2 (b) to the outer circumference 10 ', 10' ' And a refractive index distribution type optical fiber whose refractive index changes stepwise.
  • Such an optical fiber is usually spun using a composite spinning nozzle that ejects a plurality of materials concentrically stacked and discharged, but is not necessarily limited to this.
  • a composite spinning nozzle that ejects a plurality of materials concentrically stacked and discharged
  • the sheath components of the core-sheath type optical fiber include, for example, vinylidene fluoride, fluoroalkyl biel ester, methacrylate ester, estenolate acrylate, tetrafluoroethylene, and hexafluoro.
  • Lopropene, a copolymer with vinyl acetate, or the like can be used.
  • copolymers of alkyl fluoride acrylate, alkyl fluoride acrylate, etc. with methacrylates, acrylates, etc. may also be used. You.
  • polymers based on vinylidene fluoride This is a polymer, for example, full Kkabi to 7 5 9 9 wt 0/0 containing vinylidene fluoride - co-polymers of re den and Te trough Ruo Russia ethylene, fluorinated Bieriden 7 5 9 5 weight 0/0 and Te Torafuruoroe styrene 4-2 0 weight 0/0 using the copolymer comprising Kisafunoreo port propene 1 to 0 weight 0/0 using, vinylidene fluoride 7 5-9 5 wt% and Te such Traful Oroechiren 4-2 0 weight 0/0 and full Kka Bulle 1-5 wt% because Do that copolymers.
  • the polymer of the present invention is used as its central material, and the outside thereof has at least one kind of refractive index decreasing gradually.
  • a polymer or copolymer is arranged.
  • the polymer or copolymer disposed on the outside can also be produced by the method of the present invention.
  • the second invention has an object to prevent contaminants from being mixed in the devolatilization step of the polymer composition.
  • Fig. 3 shows an example of a devolatilizing extrusion device used in the second invention.
  • Fig. 3 (a) shows a partial side sectional view
  • Fig. 3 (b) shows the main parts of the device. Things.
  • the same components as those shown in FIG. 1 are denoted by the same reference numerals and description thereof will be omitted.
  • the feature of this device is that the screw direction of the screw 2 is reversed in the middle. That is, in the hollow portion la of the cylinder 1, the polymer outlet direction flow path 1 c on the polymer outlet 4 side and the rear vent direction flow path on the rear vent 5 side in the length direction of the cylinder 1. 1 d.
  • the polymer is forcibly sent from the polymer composition supply port 3 to the polymer outlet 4. Further, the polymer is forcibly fed from the polymer composition supply port 3 toward the rear vent 5 in the reactor vent flow path 1 d.
  • the conventional device has a groove 2b provided spirally on the screw 2 so that the polymer is sent in only one direction.
  • the polymer in the hollow portion 1 a of the cylinder 1 is only sent from the polymer composition supply port 3 to the polymer outlet 4.
  • part of the polymer overflows into the reactor 5 upstream of the polymer composition supply port 3 due to fluctuations in the supply amount of the polymer composition from the polymer composition supply port 3. May move. Then, a part of the polymer stays between the rear vent 5 and the polymer composition supply port 3. The polymer remaining in this portion remains in the hollow portion la without being discharged to the outside, and gradually deteriorates by being exposed to a high temperature for a long time, and becomes colored or carbonized. By-products are produced.
  • the polymer sent from the polymer composition supply port 3 to the polymer outlet 4 does not overflow, the polymer is unsteadily rearranged for the same reason as described above. It may swell to vent 5 side and move.
  • the polymer is fed from the polymer composition supply port 3 to the rear vent 5 side.
  • the polymer that has overflowed or swelled and moved to the upstream side of the rear vent 5 is forcibly sent to the rear vent 5 and discharged from the rear vent 5.
  • unnecessary retention of the polymer in the cylinder 1 can be prevented, and contamination of the polymer with contaminants can be prevented.
  • the direction (the direction of the screw) of the groove 2 b of the screw 2 is opposite to the inner edge of the opening 3 b of the polymer composition supply port 3 (nozzle 3 a) on the rear vent 5 side.
  • the distance X from the switching position is preferably designed to satisfy the following relationship.
  • D is the screw diameter
  • Y is the opening diameter (diameter of the opening b) of the polymer composition supply port 3 in the longitudinal direction of the screw.
  • the distance X is larger than + 2D, and the switching position is shifted to the rear end 5 side. If this occurs, it may be difficult to discharge the polymer that has moved to the rear vent 5 side. Also, when the value of the distance X is a negative value, the absolute value of which becomes larger than the absolute value of -0.2 Y, and when the switching position is shifted to the polymer outlet 4 side, the weight sent to the rear vent 5 As the amount of coalescence increases, the amount of feed to the front of the extruder becomes unstable, making it difficult to obtain a stable polymer. More preferably, the distance X is set to between ⁇ and 12 D in order to prevent the polymer from being sent to the rear vent 5 more than necessary. In order to further prevent the polymer from staying, it is preferable to set the distance X to 0 to + D. These positional relationships are shown in Fig. 3 (b).
  • the forevent 6 be a side vent system, and that the fork vent 2c (spring) be installed on a side where the forevent 6 vent opening is lowered.
  • the vent up in fore vent 6 can be suppressed. Also, even if sudden venting occurs, volatile components are discharged to the outside of the cylinder 1 without returning to the inside of the cylinder 1.
  • the devolatilization operation of the polymer composition in this devolatilizing extruder can be performed in the same manner as in the first embodiment.
  • industrially advantageous conditions can be set with a small-sized device, and a polymer can be obtained in which contamination is less likely to occur and volatile components are sufficiently removed.
  • the third invention prevents metal ions from dissolving, particularly from the screw and the cylinder, and preventing the metal ions from being mixed as impurities into the polymer, and improving the light-transmitting performance and the like of the polymer.
  • the purpose is to suppress the decline.
  • the surface of the screw of the screw-type devolatilizing extruder be coated with chrome or titanium nitride.
  • methyl methacrylate which is the main raw material of a methacrylic polymer, contains a few ppm of organic acidic compounds as impurities. Copper nitride, which is commonly used for screws, is corroded by this organic acidic compound and elutes iron ions.
  • a mercaptan compound is often added as a chain transfer agent.
  • the screw surface is coated with chrome or titanium nitride, the elution of iron ions can be suppressed.
  • the method of coating the surface of the screw with chrome is preferably a plating method.
  • the thickness of the chromium coating layer is preferably 20 to 80 ⁇ m.
  • the method of coating the screw surface with titanium nitride is preferably an evaporation method.
  • the thickness of the coating layer made of titanium nitride is preferably 10 to 100 m.
  • chrome content of 5-3 5 weight 0/0, the iron content of from 0-5 wt 0/0, coated with Koparuto based alloy hardness of 4 0 in the above lock Weru C scale Is preferred.
  • other metal components can be added to the cobalt alloy as long as the corrosion resistance and hardness are not deteriorated.
  • the screw frit In order to coat the screw frite with the above-mentioned alloy, it is preferable to coat the screw frit by overlaying the molten alloy.
  • the thickness of the coating layer made of this alloy is preferably 1 to 3 mm.
  • the entire screw fly may be coated with alloy, or only the end face of the screw fly facing the inner surface of the cylinder may be coated with this alloy.
  • the thickness of the coating layer made of the alloy is preferably 1 to 3 mm.
  • the screw plate itself and the inner surface of the cylinder, which are the sliding parts are also made of a material having excellent abrasion resistance with a hardness of 40 or more on a mouthpiece C scale, and 50 or more. Are more preferred.
  • the inner surface of the cylinder preferably has a hardness of 5 or more higher than that of the screw fly.
  • the screw-type devolatilizing extruder may be single-screw or twin-screw, but a single-screw extruder with less contact between the components of the device is preferred.
  • the methacrylic polymer produced by this screw-type devolatilizing extruder has excellent light-transmitting performance because there is little foreign matter contamination. It is particularly preferable to use it as a core material of a plastic optical fiber, and a plastic optical fiber having extremely excellent optical transmission performance can be obtained.
  • the structure of the optical fiber produced from the polymer devolatilized and extruded by this method is not particularly limited, and examples thereof include those similar to those described in the embodiment of the first invention. .
  • the devolatilization operation of the polymer composition in the devolatilizing extruder can be performed in the same manner as in the above-described first and second embodiments. Then, a polymer excellent in light-transmitting performance, in which contaminants are less mixed and volatile components are sufficiently removed, can be obtained.
  • the polymer composition according to the second invention is operated under the conditions satisfying the above-mentioned formula (1), and the screw used in the second invention is used. Operating under conditions that satisfy the positional relationship between the supply port and the screw will result in a polymer composition with low contaminants. You.
  • methacrylic polymer composition is devolatilized and extruded using the devolatilizing extruder using the specific material according to the third invention, so that the translucent material suitable for a plastic optical fiber or the like is obtained.
  • a high-performance methacrylic polymer can be produced.
  • Screw rotation speed 60 (min- 1 )
  • the polymer composition is prepared by bulk polymerization using methyl methacrylate alone as a monomer in the presence of a polymerization initiator and a mercaptan-based chain transfer agent.
  • the polymer composition is heated to 1 6 kg Z cm 2 2 0 0 ° C under a pressure of G, flow rate 3.3 1 0 - 4 111 3 111 1 11 continuously exits devolatilizing
  • the devolatilized polymer was supplied to the apparatus and obtained.
  • the operating conditions at this time were observed for 10 days, and are shown in Table 1.
  • core-sheath type optical fibers were manufactured using the thus obtained polymers of Example 1 and Comparative Example 1 as cores.
  • a polymer of 2,2,2-trifluoroethylmethacrylate which was separately manufactured as a material for the clad was prepared. Then, a two-layer composite spinning nozzle was attached to the polymer outlet of the devolatilizing extruder, and the core material was supplied to the inner layer of the two-layer composite spinning nozzle at a temperature of 210 ° C. In addition, the material of the clad is supplied to the outer layer of the two-layer composite spinning nozzle at another temperature of 210 ° C by another extruder to perform melt composite spinning, and the optical fiber is formed. I got a ba. The outer diameter of this optical fiber was 1 mm, and the thickness of the clad alone was 1 ⁇ .
  • the fiber was continuously spun over 150,000 m (10 days), and the transmission loss of the obtained optical fiber at a wavelength of 65 nm was measured over the entire length. It was shown to. Table 2 shows the number of times the transmission loss greatly fluctuated, exceeding 150 dBkm.
  • Example 3 From the results shown in Table 2, it was found that in Example 1 according to the present invention, a stable optical fiber with small transmission loss and little fluctuation in transmission loss was obtained. Therefore, in Example 1, the transparency was good. It was found that a polymer having good and stable composition was obtained. (Example 3)
  • the screw-type devolatilizing extruder used was a single-screw extruder with the following structure.
  • Table 3 shows the materials of the screw and cylinder used for the examples and the respective coating materials.
  • the thickness of the coating layer other than the screw flight was set to 40 im.
  • the coating layer of the screw frit was made by melting the alloy and building up the end face of the screw flit to a thickness of 2 rnm.
  • the thickness of the coating layer on the inner surface of the cylinder was 2 mm by a centrifugal method.
  • methyl methacrylate alone is used as a monomer, and bulk polymerization is carried out in the presence of a polymerization initiator and n-butyl mercaptan 170,000 ppm as a mercaptan-based chain transfer agent.
  • a methacrylic polymer mixture having a combined content of 42% by weight was obtained.
  • the mixture was heated to 200 ° C under a pressure of 16 kg Z cm 2 and continuously supplied to a screw-type devolatilizing extruder at a flow rate of 20 kg Z hr to obtain volatile components.
  • a polymer of 2,2,2-trifluoroethyl methacrylate which was separately polymerized, was supplied as a sheath material from another extruder to the outer layer of a two-layer composite spinning nozzle, and the material was supplied to the outer layer.
  • the composite fiber was melt-spun at 0 ° C to obtain a plastic optical fiber with a two-layer core-sheath structure.
  • the outer diameter of this plastic optical fiber was 1 mm, and the thickness of the sheath layer was 10 ⁇ m.
  • the content of the metal component contained in the core material of this optical fiber was measured by inductively coupled high frequency plasma emission spectrometry. Also. Optical transmission loss at a wavelength of 600 nm of the optical fiber was measured. Table 4 shows the measurement results.
  • a plastic optical fiber was manufactured in the same manner as in Example 4 except that coating was not performed using a screw type devolatilizing extruder of the material shown in Table 3, and the results in Table 4 were obtained. .
  • Screw cylinder Screw material Screw screw Screw flight Screw cylinder material Inner coated material Inner surface quality Light other than light AA Surface hardness of coating material Coating material Hardness of coating material
  • the optical fiber was continuously spun at 150,000 m (10 days), and the transmission loss at a wavelength of 6500 nm was measured over the entire length of the obtained optical fiber.
  • the average value of the transmission loss is 132 dB / km, and the number of times that the transmission loss is more than 150 dBBZ km and less than 200 dBB_km is 0 times, and more than 200 dBBZkm. 0, less than 300 dbZ km, and 0 times, more than 300 dbZkm.
  • the number of vent-ups was 0, and the extruder tip pressure fluctuation width was 10 kg Z cm 2 .
  • the content of the metal component contained in the core material of the obtained optical fiber was 26 ppb.
  • the degree of freedom of operating conditions is high, and it is suitable for industrially advantageous large-scale treatment.
  • the size of the device can be reduced, and the stagnation of the polymer in the cylinder can be prevented, and thermal deterioration of the polymer can be prevented. Therefore, industrially advantageous conditions can be set with a small device, and a polymer having stable composition and low contaminants can be obtained.
  • the c can be suppressed to be al contamination contaminants can and this to improve the characteristics of the products obtained from the polymer made et.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)

Abstract

Cette invention concerne un procédé d'extrusion-soufflage pour composition polymère. Ce procédé consiste à alimenter une extrudeuse à vis avec une composition polymère renfermant un polymère et des composantes volatiles. Cette extrudeuse comporte un cylindre avec un orifice d'alimentation et un orifice de sortie pour le polymère et une sortie pour les composantes volatiles. Une vis, maintenue en rotation dans le cylindre au niveau de l'orifice d'alimentation en polymère, évacue les composants volatiles par un orifice et extraie le polymère par un autre orifice. L'amélioration réside en ce que l'orifice d'alimentation pour polymère présente au niveau de la buse d'injection une surface d'ouverture satisfaisant à la formule (I). Dans cette formule, ζ représente la teneur en polymère, en poids (kg), de la composition polymère; [-] signifie que ζ vaut 0,50 lorsque la teneur en polymère est de 50 %) ; Q est le taux d'alimentation en polymère [m3/mn]; S représente la surface de l'ouverture de la buse d'injection [m2]; H est la profondeur de la cannelure de la vis [m]; N est le régime de broche de la vis [min -1]; D est le diamètre de la vis [m]. Cette amélioration permet une évacuation efficace des matériaux volatiles, sans ventilation.
PCT/JP2000/000313 1999-01-26 2000-01-24 Procede d'extrusion-soufflage et son extrudeuse a vis WO2000044549A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP11/17679 1999-01-26
JP01767999A JP3760059B2 (ja) 1999-01-26 1999-01-26 脱揮押出方法およびスクリュ式脱揮押出装置
JP11/26460 1999-02-03
JP11026460A JP2000226410A (ja) 1999-02-03 1999-02-03 メタクリル系重合体の精製方法

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WO2000044549A1 true WO2000044549A1 (fr) 2000-08-03
WO2000044549A8 WO2000044549A8 (fr) 2000-09-14

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116920435A (zh) * 2023-09-14 2023-10-24 天津君宇科技股份有限公司 一种高分子聚合物脱挥提浓设备

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SA112330882B1 (ar) * 2011-09-28 2018-01-24 ارلانكسيو دوتشلاند جى ام بى اتش. جهاز لإزالة مكونات متطايرة من وسط يحتوي على بوليمر
TWI649180B (zh) * 2013-04-04 2019-02-01 艾朗希歐德意志有限公司 用於自含彈性體媒介移除揮發性組份之方法及為此目的之去揮發物設備
CN104097312A (zh) * 2013-04-08 2014-10-15 上海华明高技术（集团）有限公司 排气式挤出机及使用该挤出机制造聚合物的方法

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1467045A (en) * 1973-08-15 1977-03-16 Mitsubishi Rayon Co Process for removal of volatile component form methacrylate polymer composition
US4134714A (en) * 1977-04-18 1979-01-16 General Electric Company Multi-stage continuous plastic extrusion apparatus, and extrusion screw
JPH01165779A (ja) * 1987-12-21 1989-06-29 Fukuda Metal Foil & Powder Co Ltd シリンダー用内面硬化材
JPH0349925A (ja) * 1989-07-17 1991-03-04 Sumitomo Chem Co Ltd 熱可塑性重合体組成物の脱揮押出方法
JPH03205123A (ja) * 1990-01-05 1991-09-06 Mitsubishi Heavy Ind Ltd プラスチック成形機用スクリュの表面処理方法
JPH03223404A (ja) * 1990-01-26 1991-10-02 Sumitomo Heavy Ind Ltd プラスチック成形機用スクリューの製造方法および合金層の形成方法
JPH057435U (ja) * 1991-07-12 1993-02-02 積水化学工業株式会社 押出し成形装置の押出し機
US5756658A (en) * 1995-05-26 1998-05-26 Idemitsu Petrochemical Co., Ltd. Process for preparing styrenic resin

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1467045A (en) * 1973-08-15 1977-03-16 Mitsubishi Rayon Co Process for removal of volatile component form methacrylate polymer composition
US4134714A (en) * 1977-04-18 1979-01-16 General Electric Company Multi-stage continuous plastic extrusion apparatus, and extrusion screw
JPH01165779A (ja) * 1987-12-21 1989-06-29 Fukuda Metal Foil & Powder Co Ltd シリンダー用内面硬化材
JPH0349925A (ja) * 1989-07-17 1991-03-04 Sumitomo Chem Co Ltd 熱可塑性重合体組成物の脱揮押出方法
JPH03205123A (ja) * 1990-01-05 1991-09-06 Mitsubishi Heavy Ind Ltd プラスチック成形機用スクリュの表面処理方法
JPH03223404A (ja) * 1990-01-26 1991-10-02 Sumitomo Heavy Ind Ltd プラスチック成形機用スクリューの製造方法および合金層の形成方法
JPH057435U (ja) * 1991-07-12 1993-02-02 積水化学工業株式会社 押出し成形装置の押出し機
US5756658A (en) * 1995-05-26 1998-05-26 Idemitsu Petrochemical Co., Ltd. Process for preparing styrenic resin

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116920435A (zh) * 2023-09-14 2023-10-24 天津君宇科技股份有限公司 一种高分子聚合物脱挥提浓设备
CN116920435B (zh) * 2023-09-14 2023-11-21 天津君宇科技股份有限公司 一种高分子聚合物脱挥提浓设备

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