JPS58211415A - Manufacture of resin molding material - Google Patents

Abstract

PURPOSE:To obtain molding material with high fiber content by a method wherein composite sheet integrally fixed continuous unidirectionally reinforced fiber aggregate sheet with thermoplastic resin sheet so as to realize to have a desired fiber content is slitted and then past through a heating die and, after being cooled and solidified, cut into pieces with a predetermined length. CONSTITUTION:The continuous unidirectionally reinforced fiber aggregate sheet 1 is sticked to the resin sheets supplied from resin sheet rolls 4 by means of a pair of nip rolls in order to obtain the composite sheet 6. In this case, the ratio of said aggregate sheet to said resin sheet is 70-30:30-70. Next, said composite sheet is slitted by means of a slitter 7 into slit sheets, which are past through the through hole of the heating die 8 in order to melt the resin and shaped into a desired figure with the solidification by cooling and then cut with a cutter 9. In such a manner as described above, the molding material with high fiber content is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously and efficiently producing a fiber-reinforced thermoplastic resin molding material that has a high content of reinforcing fibers and can arbitrarily change the fiber length and direction of arrangement thereof. It is.

Conventionally, thermoplastic resins have favorable properties as ensuring materials for industrial applications, etc., but they lack heat resistance,
In order to compensate for the disadvantages of thermoplastic resins, which may be insufficient in terms of shrinkage rate, rigidity, etc., for such purposes, reinforcing materials such as carbon fibers, glass fibers, and aramid fibers are used. It has evolved to the point where it has become a category of engineering plastics as a modified fiber-reinforced thermoplastic resin with significantly improved mechanical properties, heat resistance, mold shrinkage rate, etc.

For example, pellets are one form of fiber-reinforced thermoplastic resin molding material, and the main manufacturing method is (1)
) A method in which resin and reinforcing short fibers are kneaded in an extruder, the strands extruded from a die are cooled and solidified, and then cut into pellets, ``(2) Fiber containing canted rovings of reinforcing fibers impregnated with resin. There are methods such as melt-kneading blended pellets, which are a mixture of high-strength pellets and non-reinforced pellets, using an extruder, extruding the strands from a die into a cooling solidification layer, and cutting the strands into pellets. This is a method in which hot molten strands are taken from the die of an extruder, cooled and solidified, and then cut into pellets.In the Kamata method, when the reinforcing fiber content is increased, the molten strands break or become defective. This is because the molten viscous resin is effective in retaining the shape of the strand, and also has good ductility under the tension. This is because the reinforcing fiber content increases and the resin content falls below a certain level, causing the above-mentioned abnormality.For this reason, the molding material It is difficult to improve performance by increasing the fiber content to meet the required performance as an engineering material due to the troubles in the manufacturing process, and currently the fiber content is 30 to 40% by weight.
is considered to be the limit. In addition, in the manufacturing process, in the case of the former, fiber cutting, blending of resin and fiber, extruder mixing, die extrusion, and cooling solidification are performed.

There are 6 steps of pellet cutting, and in the latter case, 8 steps of resin impregnation of fibers, fiber cutting, blending of resin-impregnated pellets and non-reinforced pellets, extruder kneading, die extrusion, cooling solidification, and pellet cutting. However, both involve discontinuous processes and a large number of processes, leading to high costs.

The present invention attempts to solve the following problems,
The present invention relates to a method for continuously and highly productively producing molding materials such as pellets with a high fiber content.

The gist is that a composite sheet in which a unidirectional sheet-like continuous reinforcing fiber aggregate and a thermoplastic resin sheet are fixed and integrated to a desired fiber content is slit into a predetermined width using a slinter, etc., and then the melting point of the resin is Alternatively, a fiber-reinforced molding material is obtained by passing the slit-like material through a die heated above the softening point, cooling and solidifying the rod-like material, which is shaped into the hole shape of the die and cut into a predetermined length with a cutter. The manufacturing process involves pretreatment such as resin impregnation for fixation, and fixation of the fiber and resin.

Continuous 6 steps of slitting, die forming, cooling solidification, and cutting
It's about E.

The molding material obtained in this way can be used to provide high-performance composite molded products by molding methods such as injection molding, extrusion molding, or compression molding, and can be used for a variety of purposes such as vehicle-related structural members and machine tool parts. It can be applied in many areas.

The resin used in the present invention includes polyolefins such as polyethylene and polypropylene.

Saturated polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides such as nylon 66, nylon 6 and nylon 12), polycarbonates such as polybisphenol A carbonate, polysulfones such as polysulfone and polyethersulfone, Examples include lJ phenylene sulfide and holJ ether ether ketone, and molecular or crystal structure modified types of these resins are also applicable.

Next, methods for fixing and integrating the reinforcing fiber aggregate and the resin sheet are as follows: (1) Fixing the reinforcing fibers impregnated in a resin solution (2) Welding the reinforcing fibers impregnated in a solvent alone to a thermoplastic film, etc. (3) Method of impregnating reinforcing fibers in hot melt resin liquid and fixing them. (4) Method of fixing reinforcing fibers to a molten resin sheet. (5) Method of fixing reinforcing fibers to a resin sheet by heating. be. There are two types of fixation and integration: reinforcing fibers are fixed to one side of a resin sheet, and reinforcing fibers are fixed between resin sheets.

The method of the present invention will be explained in detail below with reference to the drawings.

FIG. 1 shows a schematic diagram of an example of an apparatus for carrying out the method of the present invention.

The sheet-shaped reinforcing fiber aggregate (1), which is parallel to the y direction and in contact with each other, is passed through the fiber supply port pair (2) that rotates at a constant speed, and then the resin liquid dissolved in the solvent is poured It is immersed in a dipping tank (3) to be impregnated with resin. The resin-impregnated aggregate is nipped and adhered to a resin sheet supplied from a resin sheet roll (4) by a pair of nip rolls (5) to form a composite sheet (6) that is fixed and integrated. Next, the composite sheet is continuously formed into slits using a slitter (7), and the slits are then passed one by one through a heated die (8) having passage holes to melt the resin and solidify it as desired. After shaping into the cross-sectional shape of
It is a continuous device that supplies 1.

As explained above (according to the present invention, the fiber content can be arbitrarily adjusted by changing the supply rate of the reinforcing fiber aggregate and the resin sheet, and is not subject to restrictions on the fiber content as in conventional manufacturing methods). , it is possible to supply molding materials with high fiber content that meet the required performance of engineering materials.

The present invention will be specifically explained below using Examples.

Example 1 A solution with a resin concentration of 3% by weight was prepared by dissolving copolymerized nylon in a mixed solvent of 50% by weight of methanol and 50% by weight of trichlorethylene, and carbon fibers (10,000 filaments) were added to this solution. The composite sheet, which was impregnated with sheet-like carbon fiber aggregates arranged in parallel to each other and then adhered and integrated with a nylon 66 film (thickness 0.05 m), was slit into slit-like objects of RL] 5 ran using a slitter. . Subsequently, the slit-like material is inserted into a circular hole (
The resin was melted by passing it through a die heated to 270° C. and having a diameter of 1.5 mm, cooled and solidified by cold air, and then cut into a molding material having a circular cross section with a length of 6 cm using a cutter.

(The fiber content of the pellet-like material obtained is 60% by weight.
This material was filled into a mold and pressed at a temperature of 280° C. and a pressure cuff of Kg/cλ for 5 minutes to obtain a molded plate with a thickness of approximately 2 mm.

Next, in the same manner as above, nylon 6 with a thickness of 0.2 mm was
Molded plates were obtained under the same conditions as above using pellet-like material obtained using 66 film (fiber content 30% by weight) and carbon fiber reinforced nylon 66 pellets (fiber content 30% by weight) obtained by the conventional method. .

The properties of the above three types of flat plates are shown in Table 1.The physical properties of the molded product with a fiber content of 60% by weight are significantly increased compared to the others.

Table-1

[Brief explanation of drawings]

FIG. 1 shows a side view of an example of an apparatus for implementing the method of the present invention, in which (1) is a sheet-like reinforcing fiber aggregate, (2) is a pair of fiber supply rolls, and (3) is a sheet-like reinforcing fiber aggregate. is a dipping tank,
(4) One or a pair of resin sheet rolls, (5) a pair of adhesive rolls, (6) a slitter for composite sheeting, (8
) indicates a die, (9) a cutter, and (10) a hopper. Patent applicant Patent attorney representing Mitsubishi Rayon Co., Ltd. 1) Taketoshi Mura Diagram 1 Procedural amendment (formality) October 1980 Commissioner of the Japan Patent Office Kazuo Wakasugi 1 Indication of the case 1988 Patent application no. 94678 No. 3 Relationship with the person making the amendment Patent applicant 2-3-19 Kyobashi, Chuo-ku, Tokyo (603) Osamu Kanazawa, President and CEO of Mitsubishi Rayon Co., Ltd. 34 Agent 2-8 Toranomon, Minato-ku, Tokyo No. 1, September 9, 1980, 6, pellet-like material obtained using ron 66 film (fiber content 30%) and carbon fiber reinforced nylon 66 pellets (fiber content %) obtained by the conventional method. A molded plate was obtained under the same conditions as above. The properties of the above three types of flat plates are shown in Table 1.The physical properties of the molded product with a fiber content of 60% by weight are significantly increased compared to the others. Table-1 4. Brief explanation of the drawings

Claims (1)

[Claims] A unidirectional sheet-like continuous fiber aggregate and a thermoplastic resin sheet are fixed and integrated at a weight ratio of 70-30 for the former and 30-70 for the latter to form a composite sheet,
The composite sheet is formed into a slit of a predetermined width, the slit is heated to a temperature higher than the melting point or softening point of the thermoplastic resin, and passed through a die having a desired cross-sectional shape to form a rod. 1. A method for producing a fiber-reinforced thermoplastic resin molding material, which comprises forming a rod-like material and cutting the rod-like material into a predetermined length.