JP2002234064A - Method for manufacturing composite material molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve productivity by accelerating an extrusion speed of a molding made of a thermoplastic composite material containing a thermoplastic resin and a plant filler. SOLUTION: A method for manufacturing a composite material molding comprises the step of extrusion molding the thermoplastic composite material containing the thermoplastic resin and the plant filler. The extrusion molding is executed by an extruder, a thermally shaping mold, a cooling mold and an extrusion auxiliary facility sequentially disposed in this order. The shaping mold is directly coupled to the cooling mold. The facility is installed at a downstream side of an extrusion line after the cooling mold. Thus, the molding is taken off while slidably moving the molding at a speed equivalent to or faster than the extruding speed of the extruder in an extruding direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite material molded article.

[0002]

2. Description of the Related Art Conventionally, a plant-based filler such as wood flour has been mixed into a thermoplastic resin such as polyethylene or polypropylene.
Various attempts have been made to obtain a composite resin composition. For example, in JP-A-7-266313, a composite pellet is prepared by pre-kneading a thermoplastic resin and wood flour,
A manufacturing method is disclosed in which the composite pellet is extruded into a mold to which a fluororesin sheet is adhered, and the extruded molded body is suppressed by a brake means. However, in the above-mentioned prior art, there was a problem that the extrusion speed could not be increased due to suppression by the braking means, and the productivity was low.

[0003]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to extrude a composite material formed of a thermoplastic resin and a plant-based filler. The idea is to increase speed and increase productivity.

[0004]

SUMMARY OF THE INVENTION The present invention provides a method for producing a composite material formed by extruding a thermoplastic composite material comprising a thermoplastic resin and a plant-based filler. Machine, heating shaping mold, cooling mold, and extrusion auxiliary equipment are arranged in this order, the heating shaping mold and the cooling mold have a directly connected configuration, and the extrusion auxiliary equipment is configured to extrude after the cooling mold. A method for manufacturing a composite material molded body, which is installed downstream of a line and extrudes while sliding in the extrusion direction at a speed equal to or higher than the extrusion speed of an extruder.

Examples of the thermoplastic resin include polyolefins such as polyethylene and polypropylene, polyamide, polyacetal, polyethylene terephthalate, polybutylene terephthalate, fluororesin, polyphenylene sulfide, polystyrene, acrylonitrile-butadiene-styrene resin (ABS resin), and acrylic resins. Examples include resin, polycarbonate, polyurethane, polyvinyl chloride, polyphenylene oxide, and ethylene-vinyl acetate copolymer.

[0006] The form of the thermoplastic resin raw material is as follows.
Pellets, granules, powders, and the like having a particle size of up to 3 mm may be mentioned, but it is preferable to use powders in terms of efficiency in kneading the raw materials. The particle size of the powder is preferably 0.1 to 1 mm.
If it is less than 0.1 mm, it is too fine and handling becomes difficult.
On the other hand, if it exceeds 1 mm, the merit will be reduced in terms of improving the kneading properties.

[0007] The above-mentioned plant-based filler is not limited as long as the resulting molded article has a plant-like appearance and gives a soft touch, and is not limited as long as it is a filler composed of plants. Wood flour such as cutting waste such as bamboo, grinding dust, sawing sawdust, and crushed material; grain or fruit husk such as rice hull and walnut husk or crushed material thereof;

The content of the above-mentioned plant-based filler is preferably 50 to 90% by weight, more preferably 55 to 80% by weight, based on the total amount of the above-mentioned thermoplastic resin. If the amount is less than 50% by weight, the feeling of wood is reduced. If the amount is more than 90% by weight, the dispersibility in a thermoplastic resin is reduced, and the physical properties are sometimes reduced.

The particle size of the above-mentioned plant-based filler is usually 1 to 1
000 μm is preferred. If it is smaller than 1 μm, it is difficult to uniformly disperse it, and if it is larger than 1000 μm, the grains are conspicuous and it becomes difficult to develop a woody appearance. More preferably, it is 10 to 300 μm.

[0010] The above-mentioned plant-based filler is usually 5 to 10%.
Since it contains about% by weight of water, it is preferable to dry in advance in an oven or the like, or to degas as steam by a degas vent during extrusion molding.

The thermoplastic composite material used in the present invention may be, if necessary, a reinforcing material such as glass fiber or carbon fiber, and a plasticizer (α, β unsaturated carboxylic acid monomer, low molecular weight Olefins), lubricants (stearic acid, stearic acid metal salts, etc.) to improve moldability, UV absorbers to improve durability such as weather resistance, UV deterioration inhibitors, oxidation deterioration inhibitors, and design Pigments for enhancing the wood texture and woodgrain, flame retardants for imparting flame retardancy, etc., acid-modified olefins for improving the affinity between thermoplastic resins and plant-based fillers, low-molecular acid-modified olefins ( For example, additives such as Sanyo Kasei Co., Ltd. (trade name "UMEX" series) may be blended into both or either of the core layer and the coating layer. Also in the above-mentioned additives, powder-like ones are preferable from the viewpoint of improving the kneading properties, similarly to the above-mentioned form of the thermoplastic resin raw material.

In the present invention, the above-mentioned thermoplastic composite material can be kneaded under heat and extruded, for example, by the following methods. 1. A thermoplastic composite material containing a thermoplastic resin and a plant-based filler is directly charged into an extruder, and extruded as it is while heating and kneading. 2. The mixture is heated and kneaded with an extruder, and once pellets are formed, extrusion molding is performed using the obtained pellets. 3. The mixture is heated and kneaded in a batch facility such as a supermixer to form a pellet, and then extruded using the pellet.

[0013] When extruding, the extruder is a commercially available single screw,
It can be used widely from general extruders such as co-axial twin screw and counter-directional twin screw to special extruders such as planetary screw extruders and KCK containerian mixers.

In the first method, it is preferable to use an extruder having a large kneading effect, such as a twin-screw kneading extruder. In the above method 2 or 3 in which the blend is pelletized in advance, use of a single-screw, twin-screw, or other ordinary extruder is preferred.

[0015] After being extruded by the extruder, the heating shaping mold and the cooling mold must be directly connected.
The direct connection of the mold makes it possible to supply the thermoplastic composite material to the core layer highly filled with the plant-based filler to efficiently obtain a molded article. In particular, it is efficient that the above-mentioned molds are directly connected in order to obtain a composite material molded body as an irregularly shaped body having an irregular cross-sectional shape.

The inner surface of the mold is preferably smooth, and more preferably has been subjected to plating, Teflon coating, or the like. The type of the plating process is not particularly limited as long as it is smooth, but chrome plating or the like is preferable in terms of cost. Preferably, the mold has the same shape. If the shape is not the same, the back pressure in the mold increases, and the extrusion amount cannot be sufficiently increased.

The extruded product exiting the cooling mold is taken up while being slid in the extrusion direction at a speed equal to or higher than the extrusion speed of the extruder by an extrusion auxiliary equipment installed downstream of the extrusion line.

The above-mentioned extrusion assisting equipment is preferably a sliding member comprising at least one or more pairs of belt-shaped or roll-shaped rotating bodies. Using the sliding member, the extruded product is sandwiched from up and down or left and right directions, and can be taken out with higher productivity by rotating and sliding in the extrusion direction at a speed equal to or higher than the extrusion speed of the extruded product. Become.

The sliding member is preferably made of a Teflon-based resin. It is more preferable that such a material be affixed, for example, to the surface of a sliding member such as the surface of a rotating body, because the extruded product and the auxiliary extrusion equipment can easily slide.

Further, it is more preferable that the rotation speed of the rotating body is controlled so as to be within a control range of a resin manometer mounted on the extruder.

(Operation) In the present invention, when extruding a thermoplastic resin and a filler, the extruded product is slid in the extrusion direction by an extrusion auxiliary equipment, so that the resistance at the time of extrusion is reduced and the extrusion speed is increased. And productivity can be improved.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to examples, but is not limited thereto. (Example 1) A thermoplastic resin molded article was continuously produced by the extrusion molding apparatus shown in FIG. As a thermoplastic resin, 100 parts by weight of polypropylene (trade name “Novatech PP” manufactured by Nippon Polychem Co., Ltd.) and wood powder (45
200 parts by weight of mesh) and 5 parts by weight of zinc stearate as a lubricant were stirred so that each component was uniform. This resin composition was charged from a raw material charging port. The barrel temperature of the twin-screw extruder was 180 ° C., the heating shaping mold was 180 ° C., and the cooling shaping mold was 120 ° C., and a 60 × 10 mm rectangular body was extruded. As an extrusion auxiliary equipment, an extruded product was sandwiched from above and below by a pair of metal rolls, and the rolls were rotated at a peripheral speed of 1.1 times the extrusion speed. The extrusion rate could be formed up to 25 kg / hr, and the obtained sample was woody, had a good surface condition, and could be manufactured continuously and stably.

Example 2 Example 1 was carried out in the same manner as in Example 1 except that a take-off machine to which a Teflon sheet was attached as shown in FIG. 2 was used as an auxiliary extrusion device.
The extrusion rate could be formed up to 25 kg / hr, and the obtained sample was woody, had a good surface condition, and could be manufactured continuously and stably.

(Comparative Example) The procedure of Example 1 was repeated except that no extrusion auxiliary equipment was used. The extrusion rate was only up to 15 kg / hr.

[0025]

According to the present invention, a composite material molded article can be obtained by the above-mentioned production method. For example, when a molded article is made of polyolefin as a thermoplastic resin and wood powder as a filler, it can be used as a housing interior material or exterior. It is provided for various uses where it is desirable to use wood such as lumber.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an example of a manufacturing apparatus used in a manufacturing method of the present invention.

FIG. 2 is a schematic view showing another example of the manufacturing apparatus used in the manufacturing method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Extruder 2 Heat shaping type 3 Cooling shaping type 4 Extrusion auxiliary equipment

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2B260 BA01 BA04 BA07 BA08 BA15 BA18 CB01 CD02 CD04 DA01 EA13 EB06 EB21 EC01 EC18 4F207 AA04 AA11 AB11 AR08 KA01 KA17 KK76 KM16 KW26

Claims (3)

[Claims] 1. A method for manufacturing a composite material molded article, comprising extruding a thermoplastic composite material comprising a thermoplastic resin and a plant-based filler, wherein the extrusion molding includes an extruder, a heating shaping mold, and cooling. The mold and the extrusion auxiliary equipment are arranged in this order, and the heating shaping mold and the cooling mold have a directly connected configuration,
The extrusion-assisting equipment is installed downstream of the extrusion line after the cooling die, and takes up the molded body while sliding in the extrusion direction at a speed equal to or higher than the extrusion speed of the extruder. Manufacturing method. 2. The method according to claim 1, wherein said extrusion auxiliary equipment uses a sliding member having a belt-like or roll-like rotating body surface. 3. The method according to claim 2, wherein the sliding member is made of Teflon (registered trademark) resin.