JP4303570B2 - Method for producing composition, composition and molded article - Google Patents

Description

  The present invention relates to a kneading extruder, and more particularly, to a kneading extruder suitable for manufacturing a master batch and a master batch obtained by using the kneading extruder.

Conventionally, as a means for improving the physical properties of plastic materials, a method of adding a filler (filler) has been frequently used. In recent years, demands for improving physical properties and reducing costs for plastic materials are increasing.
As a method of reducing product costs, a master batch is prepared by adding a high concentration of filler to plastic material, and when this is molded by injection molding or extrusion molding, fillers are added to match the performance required for the final product. There is a method of producing a final molded product by mixing with a neat resin so that the amount becomes equal.

In order for the added filler to efficiently improve the physical properties of the final product, it is important that the filler is finely dispersed in the master batch.
As a method for producing such a master batch, there are a gelation method and a batch method such as kneading with a Banbury mixer. However, since these methods cannot be produced continuously, productivity (workability, etc.) is poor, and in order to improve dispersibility, surface treatment of the filler is required, so production cost is a problem. . In addition, there is a problem that a rubber necessary for automobile materials cannot be added.

As another method, there is a method in which a fine filler and a resin material are kneaded using a twin screw extruder such as a same direction meshing type or a single screw extruder. In this method, a master batch can be continuously produced, and the dispersibility of the filler is also improved. However, since the bulk specific gravity of the filler is small, there is a limit to kneading the filler at a high concentration, and there is a problem in productivity because the discharge amount is reduced.
In contrast, attempts have been made to improve productivity by increasing the bulk specific gravity of fine fillers. Specifically, a method of compressing and using talc is disclosed (for example, see Patent Document 1). In this method, the discharge amount can be increased and the productivity can be improved. Moreover, since talc is highly concentrated, classification of talc during continuous production can be suppressed, and a high-quality master batch (the ash content of the master batch is equivalent to the charged amount) can be obtained.
However, compressed talc is inferior in dispersibility to resin compared with non-compressed talc, so that the molded product using the masterbatch obtained by this method has sufficient physical properties, although there is no problem in appearance. I could not say.

  In order to solve the above problems, the present inventors have a biaxial kneading part having a L / D (total length of biaxial part / screw diameter) of 12 or more and having a damming structure at the end of the biaxial part, A kneading and extruding machine including an extruding portion is disclosed (for example, see Patent Documents 2 and 3). The master batch produced using this kneading extruder has a finely dispersed filler, and can have a high concentration. Moreover, it can be produced with good productivity (composition discharge amount, quality stability, workability). Further, this master batch can efficiently improve the physical properties of the final molded product.

  However, when the type of compressed talc is different (when the particle size distribution is different), there is a problem that dispersibility and production stability are lowered. In addition, for example, when the dimensional configuration of the kneading part or the like is changed so as to obtain a master batch in which rubber is more highly dispersed in polypropylene, there is a problem that production stability is lowered.

JP-A-4-306261 JP 2002-79515 A Japanese Patent Application No. 2002-2182026

  An object of this invention is to provide the kneading extruder which can manufacture the composition in which each component is fully disperse | distributed with sufficient productivity, and the masterbatch manufactured using the same in view of the said subject.

According to the first aspect of the present invention, a supply unit having a forced feeder, a biaxial unit having a raw material transfer unit, a first kneading unit, and a second kneading unit in this order, the raw material transfer unit includes a supply unit. Are connected to each other, and there is a damming structure and / or a throttle adjusting valve at the end on the second kneading part side, and the biaxial part where the L / D of this biaxial part is 12 or more, and the second kneading part side, The first kneading section is composed of a reverse feed rotor and a forward feed rotor, and is composed of (total feed L / D of the reverse feed rotor) / (total L / D of the forward feed rotor). D) is from 0.4 to 2.2, L ₁ / D of the rotor is from 7 to 13, and L ₂ / D of the rotor of the second kneading part is from 0 to 10, from thermoplastic resin and rubber A composition containing two or more selected from, or one or more selected from thermoplastic resins and rubbers and a filler. A kneading extruder for use in the manufacture of the composition is provided.

  According to the second aspect of the present invention, using this kneading extruder, a composition for kneading two or more kinds selected from thermoplastic resins and rubbers, or one or more kinds selected from thermoplastic resins and rubbers and a filler. A method of manufacturing an article is provided.

  According to the 3rd aspect of this invention, the composition obtained by said manufacturing method is provided.

  According to the 4th aspect of this invention, the molded article shape | molded from the masterbatch which is said composition, and neat resin is provided.

First, the kneading extruder of the present invention will be described.
The kneading extruder of the present invention is a kneading extrusion suitable for the production of a composition containing two or more types selected from thermoplastic resins and rubbers, or a composition containing one or more types selected from thermoplastic resins and rubbers and a filler. Machine. When the kneading extruder of the present invention is used, the components of the composition can be sufficiently dispersed.

This kneading extruder is in communication with a supply section for supplying raw materials, a raw material transfer section to which the supply section is connected, a first kneading section, a second kneading section provided in this order, and a biaxial section. It consists of a single shaft part. The single shaft portion communicates with the biaxial portion on the second kneading portion side and has an extrusion function.
At the end of the biaxial portion, there is a damming structure and / or a throttle adjusting valve. The aperture adjustment valve is for adjusting the degree of kneading of the kneading part.
The single shaft portion may be a separate and independent tandem type. In other words, a tandem kneader in which the biaxial extrusion portion and the single screw extrusion portion having the above-described biaxial configuration are coupled by a resin flow path having a damming structure and / or a throttle adjusting valve may be used.
L / D of the biaxial part is 12 or more (including the screw part), preferably 16 or more, particularly preferably 20 or more.

  The supply section preferably has a forced feeder. Inserting a forced feeder improves production stability and discharge performance. There are cases where the type of filler, particularly compression talc, is different (particle size distribution) and dispersibility and production stability may not be obtained. Even in such a case, a forced feeder is used in the kneading extruder of the present invention. Production stability can be improved. Further, by using the forced feeder, the discharge amount increases, and with this increase, the compatibility between the thermoplastic resin and the rubber and the impact performance can be further improved.

The first kneading section is composed of a reverse-feed rotor and a forward-feed rotor, and (total L / D of reverse-feed rotor) / (total L / D of forward-feed rotor) is preferably 0.4-2. 2, More preferably, it is 0.4-1.5, More preferably, it is 0.7-1.5, Most preferably, it is 1.1-1.5.
By specifying (the total L / D of the reversely fed rotor) / (the total L / D of the forwardly fed rotor) of the first kneading part to the above value, the dispersion performance is improved. The adjustment can be performed by using an element type rotor (L / D = 1).
If it is less than 0.4, sufficient dispersion performance may not be obtained. Moreover, there is a possibility that neither the discharge amount increasing effect nor the production stability increasing effect by the forced feeder can be obtained. If it is greater than 1.5, the kneading is too effective and the MB hue may turn yellow. In addition, the discharge performance may deteriorate.

_L 1 / D of the rotor of the first kneading section, 7 to 13, preferably 9-11. If it is smaller than 7, sufficient dispersion performance may not be obtained. When the discharge amount is increased, the compressed talc is easily ejected from the open vent. If it is larger than 13, the above effect is saturated and the cost of the apparatus is increased. Further, kneading is too effective and the resin may be deteriorated.
There may be screws between the rotors, in which case the total rotor length is calculated.

In the kneading extruder according to the present invention, the combined use of a forced feeder and a specific rotor configuration of the kneading part improves the dispersion performance and increases the discharge amount, thereby obtaining production stability. In the kneading section, when the number of reversely fed rotors is larger than that of progressively fed rotors, the mixing and dispersing action is enhanced, but the raw materials are hardly fed out and the discharge amount is reduced. However, by using a forced feeder, a strong shearing effect accompanying an improvement in the filling rate can be obtained, and the discharge amount can be increased while maintaining the mixing and dispersing effect.
As a result, it has become possible to disperse, for example, fine compressed talc (bulk ratio: 0.5) having a low bulk density, which has been insufficient in production stability, at a high concentration. Moreover, it became possible to disperse highly compressed talc (bulk ratio: 0.8), which was difficult to disperse, at a high concentration. For example, compressed talc having an average particle diameter of 7 μm or less (4 to 5 μm or the like) can be dispersed at 70% by weight or more.

L ₂ / D of the rotor of the second kneading part is 0 to 10, preferably 0 to 6, particularly preferably 0 to 3. If it is greater than 10, the load on the motor that drives the screw will increase, so that the limit discharge amount will decrease, or the kneading will be too effective and the resin may deteriorate. In addition, the cost of the apparatus is increased.
There may be screws between the rotors, in which case the total rotor length is calculated.

The screw diameter D (mm) and the length L _f (mm) of the raw material transfer section are usually (L _f / D) / D (mm ⁻¹ ) = 0.12 to 0.33.
If it is less than 0.12, the discharge performance and stable productivity may not be obtained. If it is larger than 0.33, the effect is saturated and the cost of the apparatus is increased.

The maximum shear rate of the kneading part is usually 100 to 10,000 (second ⁻¹ ). Preferably, it is 100 to 2,800 (second ⁻¹ ), more preferably 150 to 2,200 (second ⁻¹ ), and particularly preferably 200 to 1,800 (second ⁻¹ ). The maximum shear rate is appropriately selected according to the viscosity of the material.
The maximum shear rate is obtained from the following formula.
(Π · D (mm, screw diameter) N (rpm, screw rotation speed)) / (rotor tip clearance (mm) · 60 seconds)
If the maximum shear rate is less than 100 (second ⁻¹ ), sufficient dispersion performance may not be obtained. In addition, the discharge performance may deteriorate. If it is greater than 10,000 (seconds- ¹ ), the kneading is too effective and the resin may deteriorate.

In order to enhance the effect of the forced feeder, it is preferable to provide an open vent between the first kneading part and the second kneading part.
The screw of the biaxial portion is preferably a non-meshing type, and particularly preferably a non-meshing different direction type. Moreover, it is preferable that the screw structure is a double thread.
Furthermore, it is preferable that a biaxial part has the function to adjust the flow volume of a compounding component in the edge part. Thereby, dispersibility and discharge amount can be adjusted.
A biaxial part and a single axial part can be made into an integral structure.
The kneading temperature is usually 130 ° C to 280 ° C.

Next, the composition of the present invention will be described.
The composition of the present invention comprises two or more selected from thermoplastic resins and rubbers, or one or more selected from thermoplastic resins and rubbers and a filler. Although the composition of this invention can be manufactured using said kneading extruder, it is not limited to this manufacturing method.

  Examples of the thermoplastic resin include polyolefin resins such as polypropylene and polyethylene, polystyrene resins, polycarbonate resins, polyacetal resins, polyester resins, and polyamides. Polyolefin resins are preferred. Examples of the polypropylene include homopolypropylene, random polypropylene, and block polypropylene. Examples of the polyethylene include homopolyethylene, HDPE (high density polyethylene), LDPE (low density polyethylene), and LLDPE (linear low density polyethylene).

  Examples of the rubber include natural rubber and synthetic rubber. Examples of the synthetic rubber include olefin rubbers such as ethylene-propylene rubber and ethylene-octene-1 rubber, styrene-butadiene rubber, nitrile-butadiene rubber, acrylonitrile-butadiene rubber, Examples include chloroprene rubber.

  As the filler, both organic fillers and inorganic fillers can be used. Examples of the organic filler include wood particles such as wood powder and cotton powder, fir shell powder, crosslinked rubber powder, plastic powder, and collagen powder. Examples of the inorganic filler include talc, calcium carbonate, precipitated barium sulfate, magnesium hydroxide, kaolin (aluminum silicate), silica, pearlite, sericite, diatomaceous earth, calcium sulfite, mica, potassium titanate and the like. Talc is preferred among the inorganic fillers. Moreover, when productivity is a problem because of low bulk specific gravity, a compressed product is used.

  The average particle diameter of the filler before being compressed is preferably 20 μm or less as measured by a laser measurement method. When the average particle diameter exceeds 20 μm, it is difficult to form secondary aggregates by compression, and the effect of increasing the bulk specific gravity may be reduced. The average particle size of the filler before being compressed is more preferably 15 μm or less from the viewpoint of improving productivity (discharge amount of the composition, quality stability, workability) and the like by increasing the bulk specific gravity. 10 μm or less is particularly preferable.

When the composition is produced by the kneading extruder of the present invention, these fillers are preferably used after being compressed. The bulk specific gravity of the compressed filler is preferably 0.4 or more, more preferably 0.5 or more, and particularly preferably 0.7 or more. Here, the bulk specific gravity means [weight of filler (g) / volume of filler (cm ³ )]. As the bulk specific gravity decreases, it becomes difficult to stably feed the raw materials due to problems such as bridges and ratholes in the hopper portion of the supply portion. Moreover, the effect on the discharge amount, stable productivity, etc. by a forced feeder becomes small. On the other hand, the higher the bulk specific gravity, the easier the resin melts, and high concentration kneading is possible. However, if the bulk specific gravity exceeds 2.0, the dispersibility of the filler may not be good during kneading. In addition, the shape of the compressed filler is preferably not in the form of a chip but in the form of particles from the viewpoint of good dispersibility. The chip shape means a rectangular parallelepiped shape having an average major axis of about 2 to 10 mm and an average minor axis of about 2 to 5 mm. The particulate form means something other than the chip form.

  Although the manufacturing method of a compression filler is not specifically limited, It can obtain by carrying out the pressurization process or pressure reduction process of a filler. The pressure treatment can be performed with a roller compactor (manufactured by Kurimoto Kogyo Co., Ltd., MRCP). This roller compactor is of a cantilever type that is compressed by two rolls, and the bulk specific gravity can be adjusted by the pressure of one of the rolls. The shape of the compression filler can be adjusted to a particle shape or a chip shape by a granulator in a subsequent process. As the filler, talc is most preferable from the viewpoint of satisfying the above-mentioned average particle diameter, bulk specific gravity, shape and the like.

When the composition of this invention contains 2 or more types chosen from a thermoplastic resin and rubber | gum, the usage-amount of 2 or more types of components can be made arbitrary.
When the composition of the present invention includes one or more selected from thermoplastic resins and rubbers and a filler, the filler content (content in the composition) is 1 to 90% by weight in the composition. it can.

In the case of a master batch, the filling amount of the filler is preferably 20 to 90% by weight. When the filling amount is less than 20% by weight, the cost reduction effect is small. On the other hand, when the filling amount exceeds 90% by weight, the dispersibility of the filler is lowered when the master batch is diluted with a neat resin during molding, and the physical properties may be lowered. Here, the neat resin is preferably a resin whose main component is the same resin as the resin forming the masterbatch, but may be a resin having different compatibility. Moreover, when the same resin is the main component, another resin may be mixed.
Moreover, as a filler, it is preferable to use the filler whose bulk specific gravity is 0.4 or more from a viewpoint of productivity (discharge amount, classification) of a masterbatch. Preferably it is 0.5 or more. When the bulk specific gravity is less than 0.4, it is preferable to use a compressed product. The average particle size is preferably 20 μm or less.

  In the composition according to the present invention, an organic peroxide, an antioxidant, a weathering agent, an antistatic agent, a pigment, and the like can be appropriately added depending on the intended use of the composition.

  Among the compositions of the present invention, those in which the thermoplastic resin is polypropylene and the filler is talc are suitable as a composition for forming an automobile interior / exterior member that is required to have high performance.

In addition, if the kneading extruder of the present invention is used, a master batch filled with a high concentration of filler can be obtained, and this master batch can be used as an instrument panel that requires a composition filled with a high concentration of talc. It is useful as a material for automobile interior and exterior members such as bumpers and home appliances. In addition, the current masterbatch is manufactured by the gelation method, and there is no freedom of mixing. Specifically, the possibility of granulation at the time of gelation is restricted by the compounding composition, and the production of a rubber-based composition is difficult. On the other hand, if the kneading extruder according to the present invention is used, it is possible to obtain a desired blend according to the purpose without being restricted by the blending.
In particular, the molded product comprising the masterbatch and neat resin of the present invention has higher impact resistance and gloss than the molded product comprising the conventional masterbatch and neat resin. This is because in the masterbatch of the present invention, high-concentration talc that is difficult to disperse is sufficiently dispersed, and rubber (including the rubber component in the block PP) is also adequately dispersed. is there. Therefore, it is particularly useful for applications that require impact resistance.

  The molded product of the present invention can be produced by a normal molding method such as injection molding. In this case, even if no mixing nozzle is installed in the molding machine, the composition produced by the kneading extruder of the present invention does not deteriorate in physical properties, but it is colored during molding using a pigment composition or the like. Is more likely to cause uneven dispersion of the pigment, so it is preferable to install a mixing nozzle.

Embodiment 1
Although the kneading extruder which is one Embodiment of this invention is shown in FIGS. 1-4, the kneading extruder of this invention is not limited to this. 1 is a cross-sectional view of the kneading extruder excluding the supply unit, FIG. 2 is a partial vertical cross-sectional view of the kneading extruder near the supply unit, and FIG. 3 is a cross-sectional view taken along line AA in FIG. 4 is a cross-sectional view taken along line BB in FIG.

The kneading extruder includes a supply unit 40, a biaxial screw unit (biaxial unit) 6, and a uniaxial screw unit (single shaft unit) 7.
This apparatus includes a first shaft 3 housed in a metal casing 1 and a second shaft 4 shorter than the first shaft 3, and is supplied from a hopper 42 using a screw feeder (forced feeder) 45. The blended ingredients are introduced into the Mixing Groter unit (first kneading unit) 12 through the screw unit (raw material transfer unit) 2 and melted and kneaded in the Mixing Groter unit 12 and Mixing Groter unit (second kneading unit) 13 to the tip. It is sent to the side and discharged.

  As shown in FIG. 1, the casing 1 is formed in an overall cylindrical shape, and is divided into two parts on the left and right at the approximate center. The divided portion is rotatably supported by a hinge 1a and is bent in the direction of arrow F. Note that a connecting member 1b, which is a separate member, is inserted in the divided portion of the casing 1.

  In the casing 1, there are formed a cylindrical cylinder 21, an eyebrow cylinder 20 connecting two cylindrical cylinders, and two bearing cylinders 22 and 23 formed in the connecting member 1b. In the eyebrows type cylinder 20, a first shaft 3 and a second shaft 4 each having a screw portion 2 are arranged in parallel. The first shaft 3 and the second shaft 4 are fitted into the casing 1 via screw bases 30 and 31. The base end portions of the first shaft 3 and the second shaft 4 are inserted into a gear box (not shown) installed outside the casing 1 and are rotatably supported by bearings.

  Further, since the delivery screw portion 4a at the tip of the second shaft 4 is held at a predetermined position by the molten resin interposed between this portion and the cylinder 22, the entire second shaft 4 is rotatably supported. The Similarly, since the delivery screw portion 5a at the intermediate portion of the first shaft 3 is held at a fixed position by the molten resin interposed between this portion and the cylinder 23, the entire first shaft 3 can be rotated freely. Supported.

  And the central part of the 1st axis | shaft 3 and the 2nd axis | shaft 4 opposes so that it may not mutually contact, and the pair of the mix rotator parts 12 and 13 are each provided in the middle. The mixing grower portions 12 and 13 are composed of first rotor portions 12a and 12b and second rotor portions 13a and 13b facing each other, and are formed at positions separated from each other as shown. A second screw 2a is formed between the first rotor portion 12a and the second rotor portion 13a, and a second screw 2b is formed between the first rotor portion 12b and the second rotor portion 13b. ing. An open vent (not shown) is provided above the second screw 2a.

  The first shaft 3 has an extension shaft portion 5. The extension shaft portion 5 is rotatably mounted in a cylindrical cylinder 21, and a screw 5b is formed over the entire length.

  The base end side of the extension shaft portion 5 is held in the connecting member 1b, and a flow restricting screw having a small screw groove and a small gap with the casing 1 and having a fine pitch as a damming structure in this portion. 5a is formed. In the flow rate regulating screw 5a, the flow rate of the blended component passing therethrough is regulated to the minimum, and the blended component is sufficiently kneaded.

With the above-described configuration, the casing 1 is formed with a biaxial screw portion 6 in which the first shaft 3 and the second shaft 4 are arranged in parallel, and a single screw portion 7 including an extended shaft portion 5 portion.
As shown in FIG. 2, a material supply port 8 communicating with the biaxial screw portion 6 is formed in the vicinity of the base end portion of each of the first shaft 3 and the second shaft 4 in the casing 1. The material supply port 8 is connected to a hopper 42 to which a blended component is supplied via a coil feeder 43 and a shooter 44. The shooter 44 is inserted with a screw feeder 45 in order to forcibly feed the blended components with the lid open. The supply unit 40 includes a hopper 42, a coil feeder 43, a shooter 44, and a screw feeder 45. The number of mm of the restriction of the screw feeder 45 coincides with the distance of the internal clearance. The screw feeder 45 has a pushing ability and a feeding ability.

  A discharge port 10 for the composition is provided on the end portion 9 side of the extension shaft portion 5 in the casing 1. Further, a devolatilization port 32 is formed on the base end side of the extension shaft portion 5 in the casing 1. A valve portion 11 is provided on the casing 1 on the base end side of the extension shaft portion 5. The valve unit 11 is configured as follows.

First, a vacant chamber 14 is formed on the distal end side of the delivery screw 4a, and a small-diameter passage 16 is provided in a part of the vacant chamber 14 so that the vacant chamber 14 communicates with the cylinder 21.
A cylindrical valve body 15 is inserted into the vacant chamber 14 from the outside, and the valve body 15 can be moved forward and backward in the direction of arrow H. And since the volume of the empty chamber 14 becomes small, so that the valve body 15 approaches the channel | path 16, the flow path of a mixing | blending component becomes narrow.

  The valve portion 11 communicates the biaxial screw portion 6 and the single screw portion 7 and adjusts the flow rate by bypassing the molten resin reaching the single screw portion 7. A delivery screw portion 4 a is formed at one end of the second shaft 4 so that most of the molten resin blocked by the flow rate regulating screw portion 5 a is collected and the resin is pumped into the casing 1 through the valve portion 11. It has become.

  The flow rate adjusting mechanism may have another configuration. For example, the first shaft 3 can be moved in the axial direction, and a valve body is formed by the first shaft 3 and an uneven portion formed on the inner surface of the casing around the first shaft 3. It is also possible to make a structure for adjusting the degree of opening and closing of the flow path.

Next, the operation of the continuous kneading extruder will be described.
The blended components sent from the hopper 42 are sent through the coil feeder 43 and the shooter 44. At this time, the screw feeder 45 forcibly feeds the blended components to the material supply port 8.

  The blended components introduced from the material supply port 8 are fed in the direction indicated by the arrow G by the screw portion 2 of the first shaft 3 and the second shaft 4, and are roughly kneaded by the first rotor portions 12a and 12b, and the resin is supplied. It becomes a semi-molten state and the density of the resin material increases. By increasing the density of the resin in this way, the resin conveying ability of the second screws 2a and 2b can be increased and the amount of extrusion can be increased. At this time, the rotation speed of the first shaft 3 is 10 to 1500 rpm. The rotation speed of the second shaft 4 is 1.1 times that of the first shaft 3. The maximum shear rate is calculated on the first axis 3.

  The resin material sent by the second screws 2a and 2b is completely melted and kneaded by the second rotor portions 13a and 13b. The melted and kneaded resin is sent into the empty chamber 14 by the delivery screw portion 4a, and is sent into the casing 1 through the passage 16 while the flow rate is adjusted by the valve body 15. By adjusting the flow rate in this way, the kneading residence time of the compounding component and the filling degree of the compounding component in the biaxial kneading unit 6 can be adjusted, so that the degree of kneading can be freely set by operating the valve unit 11. For this reason, the opening and closing degree of the valve part 11 can be controlled according to the state of the resin, so that the compounding components can be always uniformly kneaded.

  In addition, since the first rotor portion 12 and the second rotor portion 13 which are two sets of rotor portions are provided, the melting and kneading action of the resin is strengthened, and the amount of extrusion is greatly increased. Furthermore, the flow regulating screw portion 5a and the delivery screw portion 4a in the connecting member 1b are each independently supported, and a bearing action is generated by filling the resin between these and the cylinders 22 and 23. It is possible to prevent each screw from causing galling in the rotation range.

  Then, the composition melted and kneaded and adjusted as described above is sent to the single screw portion 7, and after necessary devolatilization from the devolatilization port 32, it is sequentially sent to the extension shaft portion 5. Extruded from the discharge port 10.

  In this embodiment, one hopper 42 is provided, but two or more hoppers 42 may be provided depending on the blending components. For example, when the bulk specific gravity of talc is low and bridges, rat holes, etc. are problematic, a hopper with a feeder dedicated to talc and a hopper with a feeder for thermoplastic resin and / or rubber can be provided. In that case, each component is mixed in the shooter and can be forcibly fed with a screw feeder.

Further, the hopper 42 can be connected to the material supply port 8 without using the shooter 44. FIG. 5 shows a partial longitudinal sectional view of an example in which the hopper is connected to the material supply port.
In the supply unit 40 ′, materials (materials having different particle sizes and the like) are supplied to the hopper 42 while being measured by the quantitative feeders 431 and 432 through the sub hoppers 421 and 422, respectively. The material supplied to the hopper 42 is forcibly supplied to the biaxial screw portion 6 by a forced feeder 45 ′.
In this example, since the supplied material is forcibly supplied to the biaxial screw part 6, classification in the hopper 42 can be prevented. In this example, three or more auxiliary hoppers may be provided in accordance with the supply material.

Hereinafter, the present invention will be described more specifically with reference to examples.
Table 1 shows the bulk specific gravity and particle size distribution of talc used in the examples.

Examples 1 to 10, 12 and Comparative Examples 2 to 9
[Production of master batch]
As materials, ethylene / propylene block copolymer (MI = 30, Idemitsu Petrochemical Co., Ltd., Idemitsu PP J-950HP) 22% by weight, ethylene-octene-1 copolymer rubber (manufactured by DuPont Dow, Metallocene LL EG-8100) ) 18% by weight and 60% by weight of talc A shown in Table 1 were used. A method for measuring the bulk ratio of talc is ASTM D1895 methodA. Moreover, 0.5 parts by weight of magnesium stearate as a dispersant and phenolic antioxidant (manufactured by Ciba Specialty Chemicals, Irganox 1010) 0.2 as an antioxidant with respect to 100 parts by weight of these total amount. 0.13 parts by weight of tinuvin-120 (manufactured by the company) and 0.13 parts by weight of tinuvin 770 (manufactured by the company) were used as the anti-mold agent.
These materials are kneaded by a kneading extruder modified with an HTM type twin-screw continuous kneading extruder φ65 (manufactured by CTE, hereinafter referred to as HTM) so as to have the apparatus configuration shown in FIG. did. The L / D of the entire HTM is 42, and the L / D of the biaxial portion is 28.
The production conditions at this time were such that the temperature of the first kneading section and the second kneading section was 160 ° C., and the temperature of the extrusion section was 180 ° C. The screw rotation speed and the tip clearance of the rotor were adjusted to the maximum shear rate shown in Table 3. The maximum shear rate was determined by the following formula.
(Π · D (mm, screw diameter) N (rpm, screw rotation speed)) / (rotor tip clearance (mm) · 60 seconds)
The rotor configuration of the first kneading section and the rotor configuration of the second kneading section are as shown in Table 2.
In Table 2, one character (forward, reverse) represents a unit of L / D = 1, and a rotor having a two-strand type twist angle of 60 ° was used.
The forced feeder used a full flight screw φ92 mm, and the clearance was 4 mm (shooter inner diameter: 100 mm). The rotation speed of the forced feeder was 120 rpm.
The HTM [(L _f / D) / D], L ₁ / D of the first kneading part, and L ₂ / D of the second kneading part were set as shown in Tables 3 and 4.
The HTM is a non-meshing different direction type screw, and the screw structure of the screw is a double thread. At the end of the biaxial kneading section, there is a damming structure as shown in FIG. 1 and an orifice adjusting function for adjusting the resin flow rate. The discharge amount of the thermoplastic resin composition was adjusted by the damming structure and the orifice adjusting function. The orifice opening was 1 mm / 25 mm.

[Production of molded products]
A mixture of 33.3% by weight of the obtained master batch and 66.7% by weight of ethylene / propylene block PP (MI = 30, manufactured by Nagayoshi Chemical Co., Ltd., 3354) was used as an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd.). FE-120, equipped with a mixing nozzle) and a mold (ASTM type) were molded under the following conditions to produce a molded product.
Molding temperature: 210 ° C
Injection time: 10 seconds Back pressure: 10%
Mold temperature: 50 ° C
Cooling time: 20 seconds

Comparative Example 1
Polypropylene 66.7% by weight, ethylene / propylene block copolymer 7.3% by weight, ethylene-octene-1 copolymer rubber (EG-8100) 6 so as to have the same composition as the molded product produced in Example 1. % By weight and talc A before compression treatment of talc (Fuji Talc Co., Ltd., TP-A25: average particle size 4.5 μm (laser method), bulk specific gravity 0.15) with respect to a total amount of 100 parts by weight Tandem type biaxial, 0.17 part by weight of magnesium stearate, 0.07 part by weight of phenolic antioxidant (Irganox 1010), 0.04 part by weight of Tin-120 and 0.04 part by weight of San-LS770 The mixture was melt-kneaded with a kneader (Kobe Steel Co., Ltd., NCM50) to produce a molded product (full compound product). The kneading conditions at this time were a kneading temperature of 180 ° C. and a screw rotation speed of 600 rpm.

Example 11 and Comparative Example 10
[Production of master batch]
The composition of the master batch was 9% by weight of ethylene / propylene block copolymer, 21% by weight of ethylene-octene / 1 copolymer rubber and 70% by weight of talc A shown in Table 1, except that the conditions shown in Tables 1 to 4 were used. A master batch was produced in the same manner as in Example 1.
[Production of molded products]
28.6% by weight of the obtained master batch and 71.4% by weight of ethylene / propylene block PP (MI = 30, manufactured by Yaga Chemical Co., Ltd., 3354) were mixed, and a composition was molded in the same manner as in Example 1.

Evaluation Example The master batch and the molded product produced in the above Examples and Comparative Examples were evaluated by the following methods.
(1) Production stability Surgery (pulsation) was evaluated as x when continuous production was not possible, △ when surging occurred but continuous production was possible, and ○ when no surging occurred .
(2) When the limit discharge amount feed amount is increased, it is possible to manufacture immediately before the feed neck occurs, talc powder is ejected from the open vent, or the screw drive power limit is reached. The amount of feed (= discharge amount).
(3) Evaluation of dispersibility of master batch (MB) MB pellets were pressed into a film (thickness of about 30 μm, about 200 mmφ) with a press molding machine (set temperature: 200 ° C.), and the dispersion state of compressed talc was changed. And a magnifying glass with a scale (magnification: 10 times). In the case where talc aggregates of 100 μm or more are confirmed, ×, in cases where 1 to 6 talc aggregates of 50 μm or less are confirmed, Δ, and in the case where aggregates are not confirmed, ◯. In addition, when pelletization was not possible, the strand piece was extract | collected and press-molded.
(4) IZOD impact strength This was performed according to JIS K 7171 (notching, 23 ° C.).
(5) Glossiness Measured according to JIS K 7105 (60 degree specular gloss).
(6) Ash content of MB Collect 2 g of pellets in a crucible, burn with a gas burner, then heat at 500 ° C. for 2 hours in an electric furnace, measure the weight of the remaining ash, and weight fraction (%) Asked.
The results are shown in Tables 3 and 4 for the above evaluation.

From Tables 3 and 4, it was confirmed that when the forced feeder was used, the limit discharge amount was larger than when the forced feeder was not used. This shows that the production efficiency of the master batch has been greatly improved. It was also confirmed that the productivity did not change even when the talc particle size distribution was different.
Moreover, since surging can be effectively prevented, it has been confirmed that stable production of the masterbatch can be performed.
Moreover, the resin molded product using the masterbatch of this invention has high Izod impact strength and glossiness compared with each comparative example which is the same compounding composition. This indicates that the master batch of the present invention can efficiently improve the physical properties of the resin. The meshing type, single-screw kneader, etc. have a small free volume, so the effect of the forced feeder is small.

  ADVANTAGE OF THE INVENTION According to this invention, the kneading extruder which can manufacture the composition in which each component is fully disperse | distributed with sufficient productivity, and the masterbatch manufactured using it can be provided.

It is a cross-sectional view of a kneading extruder excluding a supply unit, which is an embodiment of the present invention. It is a partial longitudinal cross-sectional view of the supply part of a kneading extruder. It is sectional drawing along AA of FIG. It is sectional drawing along BB of FIG. It is a partial longitudinal cross-sectional view of the example which connected the hopper to the material supply port.

Explanation of symbols

2 Screw part (raw material transfer part)
6 Biaxial screw part (biaxial part)
7 Single screw part (single screw part)
11 Valve (throttle adjustment valve)
12 Mixin Groter (first kneading part)
13 Mixin Groter (second kneading part)
40 Supply Unit 45 Screw Feeder (Forced Feeder)

Claims (3)

A supply section having a forced feeder;
A biaxial portion having a raw material transfer portion, a first kneading portion, and a second kneading portion in this order, wherein the supply portion is connected to the raw material transfer portion, and the end portion on the second kneading portion side has a damming A biaxial portion having a structure and / or a throttle adjusting valve, and the L / D of the biaxial portion is 12 or more;
On the second kneading part side, it consists of a single shaft part communicating with the biaxial part,
The first kneading part is composed of a reverse-feed rotor and a forward-feed rotor, and (total of the reverse-feed rotor L / D) / (total of the forward-feed rotor L / D) is 0.4 to 2.2 The L ₁ / D of the rotor is 7 to 13,
Using a kneading extruder in which the L ₂ / D of the rotor of the second kneading part is 10 or less ,
A method for producing a composition, wherein two or more types selected from thermoplastic resins and rubbers, or one or more types selected from thermoplastic resins and rubbers, and compressed talc are kneaded. A supply section having a forced feeder;
A biaxial part having a raw material transfer part and a first kneading part in this order, wherein the supply part is connected to the raw material transfer part, and a damming structure and / or a squeezing is provided at the end on the first kneading part side There is an adjusting valve, and the biaxial portion where the L / D of the biaxial portion is 12 or more,
On the first kneading part side, it comprises a single shaft part communicating with the biaxial part,
The first kneading part is composed of a reverse-feed rotor and a forward-feed rotor, and (total of the reverse-feed rotor L / D) / (total of the forward-feed rotor L / D) is 0.4 to 2.2 , _L 1 / D of the rotor Ru 7-13 der, using a kneading extruder,
A method for producing a composition, wherein two or more types selected from thermoplastic resins and rubbers, or one or more types selected from thermoplastic resins and rubbers, and compressed talc are kneaded. The method for producing a composition according to claim 1 or 2 , wherein the kneading and extruding machine is a tandem type including a biaxial extrusion portion that is the biaxial portion and a uniaxial extrusion portion that is the uniaxial portion.

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