JPH0564809A - Single-shaft kneading reactive extruding device - Google Patents

Abstract

PURPOSE:To contrive to optimize the extrusion and modification of material in which reaction occurs, after the mixing of additive and the like. CONSTITUTION:In a cylinder equipped with a material feed opening 2 at one end, an extrusion opening 3 at the other end and a vent port 4 between the two openings, a rotor 5 equipped with screws 5A, 5B, 5C, 5D and 5E is rotatably fitted. Between the screws 5B and 5C on the rotor 5, a mixing part 6, on the outer peripheral surface of which semi-spherical cavities 8 are concavely provided. Further, a rotating tubular body 10 having a large number of through holes on its outer periphery is fitted over the mixing part 6. On the cylinder 1, an additive feed opening 7 is provided on the upper part side of the mixing part 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-screw kneading reaction extruder used for melting and kneading reactions of synthetic resins and rubber materials.

[0002]

2. Description of the Related Art Conventionally, a single-screw kneading / extruding apparatus of this kind is known as shown in FIG. 5 (see, for example, Japanese Patent Publication No. 2-8561). This extruder has a material supply port 21 at one end and an extrusion port 22 at the other end, and a rotor 25 provided with a screw on the outer periphery is rotatably mounted in a cylinder 24 provided with a vent port 23 in the middle. The rotor 25 is fitted and is rotated by a motor 26.

The tip of the rotor 25 (the end on the side of the extrusion port 22)
A mixing portion 28 having a hemispherical cavity 27 recessed therein is provided, and a cylindrical ring 30 having a hemispherical cavity 29 recessed inside is rotatably fitted to the mixing portion 28. It is possible to mix pigments and liquid additives, or to mix different kinds of polymers into the melt.

[0004]

The above-mentioned prior art is suitable for mixing additives (colorants such as pigments) with molten polymer and for homogenizing the temperature and composition of the molten polymer. It is not applicable to those requiring a time for the reaction to proceed after mixing the additives. Usually, a twin-screw kneading extruder is used for a reaction such as grafting to a polymer, but there are problems that the equipment cost is high, the cost cannot be reduced, and it is difficult to generate a high extrusion pressure. there were.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is a single-screw kneading reaction extruder suitable for extruding a material accompanied by a reaction after mixing additives and the like. To provide.

[0006]

In order to achieve the above object, the present invention takes the following technical means. That is, according to the present invention, a rotor having a screw on its outer periphery is rotatably fitted in a cylinder having a material supply port at one or a plurality of locations, a discharge port at an end, and a vent port in the middle. In the single-screw kneading / extruding device described above, the rotor is provided with a mixing portion located in the middle of the material supply port and the vent port and having a hemispherical cavity recessed in the outer peripheral surface at one or a plurality of locations. A rotary cylinder having a large number of through holes on the outer periphery or a cavity on the inner surface is externally fitted to the mixing section, and the cylinder is provided with an additive supply port located on the upper side of the mixing section. ..

[0007]

According to the present invention, when an additive composed of a low-viscosity low-molecular substance such as a monomer or a catalyst is supplied to a polymer from an additive supply port on the upstream side in the material flow direction of the mixing part, the mixture is freely rotated in the mixing part. By the rotating cylinder, the material polymer with a viscosity difference and the additive are uniformly mixed, the reaction proceeds on the lower side of the mixing section, and further the pressure is reduced, so that a reaction by-product or excess monomer (solvent) is discharged from the vent port. ) Etc. are discharged. Then, the material polymer or the like, which has completed the reaction, is pressed again by the screw, becomes a modified material, and is extruded in a molten state.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention, in which a cylinder 1 has a material supply port 2 at one end, a discharge port 3 at the other end, and a vent port 4 at an intermediate portion, While the polymer is fed from the outside by a device (not shown), the polymer is heated or cooled.

Reference numeral 5 is a rotor, and five screws 5A, 5 are provided on the outer circumference.
B, 5C, 5D, 5E are formed, and a mixing section 6 is formed between the second-stage screw 5B and the third-stage screw 5C, which is rotatably fitted in the cylinder 1 and is not shown in the drawing. It is designed to be rotated by the drive device. The vent port 4 is located above the fourth-stage screw 5D of the rotor 5, the material supply port 2 is located above the first-stage screw 5A, and it is located on the upper side of the mixing section 6 and the cylinder 1 is provided with an additive supply port 7.

A plurality of hemispherical cavities 8 are recessed in a staggered manner on the outer peripheral surface of the mixing portion 6, and a rotary cylinder 10 having a large number of circular through holes 9 on the outer periphery is rotatably fitted on the outer periphery. (See FIGS. 2 and 3). 11 is the material supply hopper,
Reference numeral 12 is an additive tank, 13 is an additive supply pipe connecting the tank 12 and the additive supply port 7, and a supply pump 14 is provided on the way.

In the first embodiment, when a material consisting of a mixture of a polymer (eg polypropylene) and maleic anhydride is charged from the hopper 11, the material is plasticized and melted while being transferred by the first and second stage screws 5A and 5B. And mix with the reactive peroxide (e.g. dicumyl baroxide solution) injected through the additive supply port 7.
Up to 6

The molten material and the peroxide that have entered the mixing section 6 move between the cavity 8 recessed in the mixing section 6 and the through hole 9 of the rotary cylinder 10 so that both materials having different viscosities become uniform. However, during the mixing reaction, the mixture of the molten polymer and maleic anhydride is allowed to generate radicals in the polymer molecular chain by the radicals generated by decomposition of the peroxide. Graft maleic anhydride.

In this way, the polymer melt, which has completed the reaction, reaches the fourth-stage screw 5D having a deeper screw groove depth, and is exposed under reduced pressure there, and reaction by-products, solvents, etc. are vented. After being extracted and removed from No. 4, it is extruded from the discharge port 3 through the fifth-stage screw 5E to have a required extrusion pressure. Incidentally, by further mixing the polymer grafted as described above with a polyamide,
Polypropylene / polyamide polyalloys can be produced.

FIG. 4 shows the second embodiment of the present invention. The difference from the first embodiment is that the screw of the rotor 5 is increased by one stage to six stages, and mixing sections 6A and 6B are provided at two places, and The additive supply ports 7A and 7B are provided on the upper side of the mixing sections 6A and 6B, and two kinds of additives can be mixed and reacted in two stages. In the second embodiment, the fifth stage screw 5E
Is the same as that of the first embodiment except that the groove depth is increased and the vent holes 4 are provided correspondingly, and the additive tanks 12A and 12B are provided. The same reference numerals are given and detailed description is omitted.

In each of the above embodiments, the rotary cylinder 10 is provided with the through hole 9, but a hemispherical cavity similar to the mixing portions 6, 6A and 6B can be provided on the inner surface. The present invention is
The present invention is not limited to the above-mentioned embodiments, and the design can be changed as appropriate, for example, by providing a material supply port in a plurality of stages, and can be adopted not only in an extrusion molding machine but also in an injection molding machine.
Further, it is possible to carry out a kneading reaction or the like of the rubber material.

[0016]

As described above, according to the present invention, a screw is provided on the outer circumference in a cylinder having a material supply port at one or a plurality of locations, a discharge port at an end, and a vent port in the middle. In the single-screw kneading / extruding apparatus in which the rotor is rotatably fitted, the rotor is provided with a mixing section located between the material supply port and the vent port and having a hemispherical cavity recessed in the outer peripheral surface. Alternatively, a rotary cylinder having a large number of through holes on the outer periphery or a cavity having an inner surface is externally fitted to the mixing portion, and the cylinder is located on the upper side of the mixing portion and has an additive supply port. Since it is characterized in that a liquid additive or a reactive monomer is added to the polymer to uniformly mix the polymer, the polymer is modified by diluting it or grafting it. Quality and reaction after mixing It is possible to improve the reactivity it is possible to hold the necessary time.

A twin-screw kneading extruder was conventionally used for the reaction such as grafting of a polymer, but the single-screw kneading extruder of the present invention is inexpensive and easy to generate a high extrusion pressure. As a result, the equipment cost can be reduced and the quality of the molded product can be improved.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view showing a first embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of the mixing section of FIG.

FIG. 3 is an enlarged cross-sectional view taken along the line AA of FIG.

FIG. 4 is a schematic vertical sectional view showing a second embodiment of the present invention.

FIG. 5 is a vertical sectional view showing a conventional example.

[Explanation of symbols]

 1 Cylinder 2 Material supply port 3 Discharge port 4 Vent port 5 Rotor 5A Screw 5B Screw 5C Screw 5D Screw 5E Screw 6 Mixing part 6A Mixing part 6B Mixing part 7 Additive supply port 7A Additive supply port 7B Additive supply port 8 Cavity 9 Through hole 10 Rotating cylinder

Claims (1)

[Claims] 1. A rotor having a screw on its outer periphery is rotatably fitted in a cylinder having a material supply port at one or a plurality of locations, a discharge port at an end, and a vent port in the middle. In the single-screw kneading / extruding apparatus, in the rotor, a hemispherical cavity having a hemispherical cavity is provided at one or a plurality of mixing portions which are recessed in an outer peripheral surface, the mixing portion being located between the material supply port and the vent port. A rotary cylinder having a large number of through holes on the outer periphery or cavities on the inner surface is externally fitted to the mixing section,
A single-screw kneading reactive extrusion apparatus, wherein an additive supply port is provided on the upper side of the mixing section in the cylinder.