JPH04201412A - Woven fabric reinforced resin composite material - Google Patents

Abstract

PURPOSE:To obtain unconventionally new type plate-like woven fabric reinforced resin composite material by a method wherein woven fabric is present in substantially void-free continuous phase matrix made of thermoplastic resin and, at the same time, the surface of the material concerned is covered by thin layer made of said resin. CONSTITUTION:The woven fabric reinforced resin composite material concerned is produced through the formation of matrix, which is formed by forcing thermoplastic resin in the texture of woven fabric and, at the same time, the surface of the woven fabric is thinly covered by the resin. The composite material concerned consists of 30-90wt.% of woven fabric and the remainder or 70-10wt.% of thermoplastic resin. The manufacturing method of the composite material concerned is to thermally melt the thermoplastic resin film under the condition being piled up with the woven fabric made of reinforcing fiber, which has the melting point higher than that of said resin or which is infusible, and then cool the resultant film and fabric under pressure or to dip the woven fabric in a molten thermoplastic resin bath, pass the resultant fabric through a slit and cool it under pressure or to coat the woven fabric with molten resin and cool it under pressure. Or fiber made of thermoplastic resin is woven in the woven fabric at the weaving of the woven fabric so as to be melted by heating in order to manufacture the composite material concerned. In this case, reinforcing fiber must be present both in woof and in warp.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing a molded article containing a thermoplastic resin and reinforcing fibers, and a molded article.

(Conventional technology) Many fiber-reinforced synthetic resin molded products are known.

Generally, short reinforcing fibers are uniformly dispersed in a molten synthetic resin, and then molded by injection molding or the like. With this method, it is possible to make molded products with complex shapes and large-sized molded products.

It is also known to make fiber-reinforced composites by applying a thermosetting resin emulsion to a reinforcing fiber structure, such as a non-woven or woven fabric, and curing it with heat.

(Problems to be Solved by the Invention) An object of the present invention is to provide a new type of woven fabric reinforced resin composite material different from conventional ones and a method for producing the same.

(Means for Solving the Problems) The present invention first provides a fiber-reinforced resin composite material in which the fibers are in the form of a woven fabric and the resin is a thermoplastic resin that melts at a temperature lower than the melting point (if any) of the fibers. A plate-shaped woven fabric-reinforced resin in which the resin constitutes a continuous phase matrix with substantially no voids, a woven fabric exists in the matrix, and the surface of the resin is coated with a thin layer of the resin. It is a composite material.

The present invention also provides a method for making a composite material, in which one film of thermoplastic resin and one sheet of woven fabric are stacked, or two or more thermoplastic resin films and one or more woven fabric are stacked alternately, Melting the thermoplastic resin film by heating to a temperature above the melting point of the thermoplastic resin and below the melting point of the reinforcing fibers,
This method is characterized in that the molten resin is then filled into the openings of the woven fabric by applying pressure in the direction of the plane of the woven fabric, that is, at right angles to the woven fabric, followed by cooling.

The present invention also provides a method for making the composite material, in which the woven fabric is passed through a molten thermoplastic resin, and then a predetermined amount of resin is applied to the woven fabric by passing it through a slit. This method is characterized by filling the molten resin into the openings of the fabric by applying pressure in the direction of the plane of the fabric, and then cooling it.

Furthermore, the present invention provides a method for making a composite material by coating one or both sides of a woven fabric with a molten thermoplastic resin, and then applying pressure in the direction of the plane of the woven fabric to apply the molten resin to the woven fabric. This method is characterized by filling it into the eye and then cooling it.

Finally, the present invention provides a method for making a composite material, in which thermoplastic resin fibers are woven into a woven fabric of reinforcing fibers, the woven fabric is heated to a temperature higher than the melting point of the resin, and then This method is characterized by forming a matrix phase of the resin by applying pressure and then cooling it.

In the woven fabric-reinforced resin composite material of the present invention, the thermoplastic resin is press-fitted into the weaves of the woven fabric to form a matrix and thinly coats the surface of the woven fabric.

Generally, the thickness of a plate-like composite material is controlled by the thickness of the woven fabric.

The amount of resin is such that the amount of resin per unit area is sufficient to fill the openings of the woven fabric and coat the front and back sides of the woven fabric. Generally, the woven fabric itself accounts for 30-90% by weight, preferably 50-85% by weight, and the remaining 910-10% by weight, preferably 15-50% by weight, is thermoplastic resin.

Thermoplastic resins are not particularly limited, but include, for example, polyethylene, polypropylene, polyester (e.g., polyethylene terephthalate and polybutylene terephthalate), aromatic polycarbonate, polyphenylene ether, polyamide, or resin alloys such as aromatic polycarbonate/polybutylene terephthalate, polyphenylene ether/polyamide. can be mentioned. The resin contains stabilizers, flame retardants, depopulating agents, antistatic agents, pigments,
It may also contain dyes, fillers, etc.

The reinforcing fibers must have a higher melting point than the resin of the film or be infusible, and can be selected from, for example, glass fibers, carbon fibers, and the like. Glass fiber is particularly preferred. The technique for weaving these is well known, and any suitable weave structure such as plain weave, twill weave, satin weave, and leash weave can be used. Although it is possible to use a knitted structure, it is not preferable from the viewpoint of reinforcement purpose. The fibers can be provided with surface treatment agents, especially coupling agents.

The woven fabric reinforced resin composite material of the present invention is used for reinforcing molded products made of thermoplastic resin. That is, a thermoplastic resin (
The composite material is contained in a molded body made of preferably the same resin and integrally molded. For example, in compression molding, a molded product whose surface is reinforced with a woven fabric can be obtained by placing a woven fabric-reinforced resin composite material on the surface of a mold and charging resin thereon, or by performing the process in the reverse order.

In fiber-reinforced composites, instead of uniformly distributing the reinforcing fibers in the molded article, it is conceivable to use waste reinforcing fibers in areas where stress is likely to be applied, particularly near the surface of the molded article. This can usually be done by first placing the reinforcing fibers in a mold, then inserting the synthetic resin, and then heating and pressurizing the mold.

However, with this method, it is difficult to arrange the reinforcing fibers at desired locations in the molded product in a desired orientation.

A particularly big drawback is that the reinforcing fibers tend to stand out on the surface of the molded product, or conversely, tend to get deep inside the molded product. The above problems become particularly noticeable when producing large molded products with complex shapes. However, if the plate-shaped woven fabric composite material of the present invention is previously cut and deformed into an appropriate shape, the above problem can be solved.

In addition, in the composite material of the present invention, the matrix is a thermoplastic resin, and if the type of resin is selected to be compatible with the resin of the molded product body, the reinforcing material on the surface of the molded product will not peel off. There is no oxidation, and an excellent strengthening effect can be obtained.

A method for manufacturing the woven fabric reinforced resin composite material of the present invention will be described.

First, in the first method, a film of thermoplastic resin is layered with a woven fabric made of reinforcing fibers or infusible reinforcing fibers having a melting point higher than that of the thermoplastic resin, and the film is reinforced at a temperature higher than the melting point of the thermoplastic resin and reinforced. The thermoplastic resin film is melted by heating to a temperature below the melting point (if any) of the fibers, and then the molten resin is filled between the fibers of the woven fabric by applying pressure in the direction of the plane of the woven fabric. , followed by cooling to produce a plate-like composite in which the fabric is present in a matrix of thermoplastic resin and whose surface is coated with a thin layer of thermoplastic resin.

If a sheet of woven fabric and a sheet of resin film are stacked together, and the resin is sufficiently melted and pressed with a sufficiently high pressure, the resin will reach the opposite side of the woven fabric, creating a plate-like composite with almost the same front and back sides. wood is obtained. However, the amount of resin on the front and back sides does not necessarily have to be the same. Alternatively, one or more woven fabrics may be sandwiched between two or more thermoplastic resin films and heated.
You can also press it.

The above-mentioned plate-like composite material does not necessarily have to be flat, and may be curved to match the shape of the surface of the molded product on which it is placed, as will be described later. However, even if a flat one is used, it can be easily deformed in the molding process described later.

In the second method, a predetermined amount of resin is applied to the fabric by passing it through a bath of molten thermoplastic resin and then passing it through a slit. A slit is provided at the bottom of the bath so that the fabric can be passed from top to bottom. Alternatively, the slit can consist of two edges or rolls placed above the bath.

Subsequently, the wA cloth is pressurized and cooled.

In a third method, molten thermoplastic resin is coated on one or both sides of the woven fabric. An extruder can be used for this, and in the case of double-sided coating, it is preferred to run the fabric vertically from top to bottom before passing it through a die. This is followed by pressurization and cooling.

In the fourth method, when weaving a woven fabric made of reinforcing fibers, fibers made of thermoplastic resin are woven into the fabric.

Reinforcing fibers must be present in both the warp and weft. The thermoplastic resin fibers to be melted later may be present only in one of the warp and weft, but the fibers must be woven with sufficient density to form a matrix with virtually no voids after melting. There is. In this method, the proportion of the thermoplastic resin is preferably smaller than in other methods, for example, 15 to 40% by weight, but is not limited thereto. In this fourth method, since the thermoplastic resin is already present between the reinforcing fibers, it is easier to integrate the reinforcing fibers and the thermoplastic resin, and the pressure of the subsequent pressurization is relatively low. It can be small. The woven fabric is cooled after being pressurized.

In the following, the invention will be further explained by means of examples.

(Example) 1. Manufacture of board composite material
l') was prepared. Polypropylene film (thickness 0
．． Two rolls of No. 5, ) were prepared, and the films were stacked on the front and back sides of the above-mentioned glass fiber woven fabric in a sandwich manner while being continuously fed into a heating furnace to completely melt the polypropylene. At the exit of the furnace were two pairs of pressure rolls through which the woven fabric and film were passed. After successively passing through a cooling roll, the resulting hard plate-like composite material was cut.

In the resulting composite material, the polypropylene completely filled the openings of the woven glass fiber fabric, and the surface of the woven fabric was covered with a thin layer of polypropylene. Although the surface was completely flat, the structure of the woven fabric was completely intact, indicating that it was made of cloth.

2. Usage example: AZdel (registered trademark) PM, a resin body containing long fibers
The above composite material was used to further strengthen the 10400 molded product. A zde + is a 3.7 mm thick plate made of 40% by weight of a random mat of glass fibers and 1% by weight of 60% polypropylene.

When this was placed in an oven at 210° C. for about 3 minutes, the polypropylene completely melted, forming a thick blanket that swelled to about three times its thickness. In addition, the two plate-shaped composite materials made in 1 above were placed in the same oven for about 3 minutes to melt the polypropylene and form a soft candy-like material with a shiny surface.

The above-mentioned softened composite plate was quickly placed on the lower mold of a compression molding mold at about 50°C. Next, the heated and swollen long fiber-containing resin body was quickly but carefully taken out of the furnace and placed on the plate-like composite material. A total of four sheets were stacked. Note that the lower two pieces of the swollen long fiber-containing resin body are slightly smaller than the horizontal part of the lower mold, and the upper two pieces are even smaller than that.

Another softened composite plate was placed on top of this.

This manual operation was performed quickly for less than 10 seconds to prevent temperature drop. The amount of material to be put into the mold is roughly determined based on the cavity volume, and the rest is adjusted through trial and error.

Next, the upper mold connected to the hydraulic press is lowered, and from just before contact, it is lowered at a speed of 20 weight wn/sec, and 12 weight g/-
Tighten with pressure. When the upper mold reaches a predetermined position, a limit switch stops the upper mold. After cooling in this state using a mold temperature controller, the mold was opened and the molded product was taken out.

The woven fabric was visible on the front and back sides of the molded product, but the woven fabric was covered with a thin resin layer, and there were no irregularities at the edges of the woven fabric.

The characteristics of the plate-shaped composite material as a raw material, a comparative product molded only from a long fiber-containing resin body, and a molded product of the present invention were measured. The results are shown below.

Tensile strength (kg/J>2500 980
1500 tensile modulus (lie/a&) 220000 5
9700 100000 Flexural modulus (kg/a()
14oo0o 56200 9o00゜Application Person 2 Japan GE Plastics Co., Ltd.

Claims (1)

[Claims] 1. In a fiber-reinforced resin composite material, the fibers are in the form of a woven fabric, the resin is a thermoplastic resin that melts at a temperature lower than the melting point (if any) of the fibers, and the resin is substantially A plate-shaped woven fabric-reinforced resin composite material comprising a continuous phase matrix with no upper voids, in which a woven fabric exists, and whose surface is coated with a thin layer of the above-mentioned resin. 2. In the method for making a composite material according to claim 1, one film of thermoplastic resin and one sheet of woven fabric are stacked, or two or more thermoplastic resin films and one or more woven fabric are stacked alternately. , heating to a temperature above the melting point of the thermoplastic resin and below the melting point of the reinforcing fibers to melt the thermoplastic resin film;
A method characterized in that the molten resin is then filled into the weaves of the fabric by applying pressure in the direction of the plane of the fabric, followed by cooling. 3. In the method of making a composite material according to claim 1, a predetermined amount of resin is applied to the woven fabric by passing the woven fabric through a molten thermoplastic resin, and then passing through a slit, and then the woven fabric is woven. A method characterized in that the molten resin is filled into the weave of the fabric by applying pressure in the direction of the plane of the fabric and then cooled. 4. The method for making a composite material according to claim 1, wherein the molten thermoplastic resin is coated on one or both sides of the woven fabric, and then the molten resin is applied to the woven fabric by applying pressure in the direction of the plane of the woven fabric. A method characterized by filling the eye into the eye and then cooling. 5. In the method for making a composite material according to claim 1, thermoplastic resin fibers are woven into a woven fabric of reinforcing fibers, the woven fabric is heated to a temperature higher than the melting point of the resin, and then the woven fabric is heated in the direction of the plane of the woven fabric. A method characterized in that a matrix phase of the resin is created by applying pressure and then cooling.