JPH06305034A - Preparation of frp - Google Patents

Abstract

PURPOSE:To improve workability, to prevent trouble from occurring and to mold an FRP with high quality by a method wherein a composite fiber base material prepd. by binding a roving arranged in one direction with a specified width and a fabric with a binder is used and the base material is impregnated with a resin and it is molded and cured in a heated die. CONSTITUTION:A composite fiber base material to be used is a fiber base material prepd. by binding a plurality of fiber rovings arranged in parallel in the continuous direction of a fiber fabric with a specified width on at least one face of the continuous fiber fabric. The constitution of this base material is an material wherein fabrics are bound usually on one or both faces of the roving. After this base material is continuously impregnated with a heat-curable resin such as an unsatd. polyester resin, it is pulled in a die, where it is molded and heat-cured to prepare an FRP.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a fiber reinforced plastic molded product (hereinafter referred to as FRP) by a pultrusion molding method.
Relates to a method for continuously manufacturing.

[0002]

2. Description of the Related Art FRP has many features such as light weight, high strength, and excellent corrosion resistance, and is widely used in automobiles, construction and electric equipment members as well as housing members such as bathtubs, septic tanks and tanks. There is a pultrusion molding method as one of the FRP molding methods.

The pultrusion molding method is usually a method of impregnating glass fiber with a thermosetting resin, and then continuously drawing it into a die to shape and heat it to produce an FRP. It has many features such as high productivity and
Widely used as structural members such as pipes, angles, channel materials, cable troughs, ladders, and gratings.

The most common pultrusion method is to prepare a predetermined number of glass fiber rovings in the form of rolls (bobbins), pull them out one by one, and take out each one individually. It is a method of pulling into a die and preforming it through some guides provided in the.

[0005]

However, in the above-mentioned general pultrusion molding method, even if only one glass fiber roving is passed through several guides, it takes a lot of preparation time. In addition, a large number of rovings must be passed through a number of designated guides. Moreover, since a large number of bobbins wound with rovings are required, a large space is required for the bobbin storage space.

Further, when the glass fiber roving is introduced into the die, there is no lateral restraint, so that a deviation occurs, and the glass content of the obtained molded product tends to be uneven depending on the location. There is also.

Further, even in the actual production of FRP, when a plurality of continuously moving rovings are entangled with each other or the roving is lost, a connection with a new roving is required for each roll. As a result, troubles frequently occur and the work becomes complicated. In particular, when manufacturing a large-sized molded product, it is necessary to use several hundred glass fiber rovings, so the situation is more serious, and measures against the above matters become a very important issue. ing.

[0008]

SUMMARY OF THE INVENTION In view of the above problems, the present invention aims to improve workability at the time of pultrusion molding, prevent troubles, and form a high quality FRP.
It is an object to provide a method for producing FRP.

The present inventor has conducted extensive studies in view of the above problems, and as a result, uses a composite fiber base material in which a roving aligned in one direction with a predetermined width and a fabric are continuously bonded with a binder, After impregnating the composite fiber substrate with a resin,
It has been found that the above problems can be solved by drawing into a heated die and shaping / curing the die to continuously produce FRP, and the present invention has been completed.

Next, the present invention will be described in detail.

The composite fiber base material (A) used in the present invention is obtained by bonding a plurality of fiber rovings aligned on at least one surface of a long fiber fabric with a predetermined width so as to be parallel to the length direction. It is the obtained fiber base material.

It is preferable that the composite fiber base material (A) is continuously produced as long as possible, and it is preferable to use it by winding it around a bobbin. The length and width are not particularly limited, but usually the length is 100 to 1000 m and the width is about 3 cm to 2 m. The thickness is usually 1 to 10 mm. The interval between the aligned rovings is also not particularly limited, but is, for example, 0 (a state where adjacent rovings are in close contact) to 30
cm, and in that the thermosetting resin can be uniformly impregnated,
It is preferable that the rovings of the neighbors are in close contact with each other.

As the base material (A), a roving having a fabric bonded to both sides or one side of the roving can usually be used. It is also possible to stack and use so that it becomes a multi-layer.

Of course, the fiber base material (A) may be manufactured by selectively adjusting the amount and ratio of the roving and the fabric, the width and the thickness, etc., according to the specifications of the molded product to be obtained. preferable.

As the fabric and roving constituting the base material (A), any known and commonly used one can be used. As the substance (fiber) of the base material (A), various organic fibers and inorganic fibers such as glass fiber, carbon fiber and aramid fiber can be used or used in combination.

The types of fibers of the fabric and roving in the base material (A) may be the same or different.
A combination of rovings and fabrics of different densities can also be used. The most general-purpose substrate (A) is a substrate obtained by combining glass fabric and glass roving and combining them.

The connection between the fiber fabric and the fiber roving may be a physical connection such as a method of sewing the fabric by roving, but an adhesive is more preferable. For example, a fiber roving to which a thermosetting resin is adhered may be used. There is a method of bringing them into close contact with a fabric for heat-curing adhesion, or making a roving having a thermoplastic resin adhered thereto come into close contact with a fiber fabric to cause heat fusion.

The type (form) of the fiber fabric constituting the base material (A) is not particularly limited, but any of cloth, net, mat and the like can be used. Above all, a cloth or net is preferable because it can restrain the lateral deviation of the roving constituting the base material (A) and can be continuously used for a longer time. It is also possible to use a glass mat, swirl mat, bale mat, or the like.

In the present invention, after the base material (A) is continuously impregnated with the thermosetting resin, the base material (A) is squeezed so that a predetermined resin adhesion amount is obtained, and it is heated in advance. It is drawn into a die and shaped and cured to produce an FRP molded product.
The material and structure of the die used at this time and the type of the impregnation bath are not particularly limited, and any conventionally used one can be adopted.

In the pultrusion molding of the present invention, the base material (A) is preformed according to the shape of the molded product to be obtained in the steps before and after impregnating it with the thermosetting resin. It is preferable to pull it into a die.

As the thermosetting resin with which the base material (A) is impregnated in the present invention, any of the known and commonly used thermosetting resins can be used. For example, unsaturated polyester resin, vinyl ester resin, epoxy resin, urea resin, phenol resin. And the like, and unsaturated polyester resins are particularly preferable. If necessary, a thermoplastic resin such as polyvinyl chloride, polypropylene resin, polyethylene resin or nylon resin can be used together with the thermosetting resin.

The thermosetting resin may be used by being filled with a filler such as calcium carbonate, aluminum hydroxide or glass powder, and various additives such as a silane coupling agent and a release agent may be added. You may use a drug together. Further, a pigment may be added for coloring.

The conditions for curing the base material (A) impregnated with the thermosetting resin may be appropriately adjusted depending on the type of resin, the presence or absence of a filler, the thickness and shape of the molded product to be obtained, and the like. However, the curing condition when using the unsaturated polyester resin is, for example, 80 to 150 ° C. and 0.5 to 10 minutes.

In the present invention, not only molding is performed using only the base material (A), but also the base material (A) and the base material other than the base material (A) are superposed and then thermoset. It is also possible to adopt a method in which the resin is impregnated and then molded.

Specifically, the base material (A) and the fiber fabric (B) having a higher density than the fiber fabric in the base material (A) are used in combination, and the base material (B) is the center, and at least The fibrous base material (A) is superposed on one side so that the side of the fibrous fabric is the surface, then impregnated in a thermosetting resin bath, and then drawn into a preheated die to shape and cure. You may let me. This is preferable because a molded product having a high density in the central portion of the cross-sectional shape can be obtained.

According to the present invention, a continuous molded product having a desired sectional shape can be obtained. The long molded product thus obtained is cut into a desired length, if necessary, and used for the intended purpose.

[0027]

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto.

Example 1 A continuous glass fiber roll of 2300 g / km, which was aligned on one side of a continuous glass fiber cloth of 200 g / m ^{2 having} a width of 266 mm so as to be parallel to the longitudinal direction of the cloth.
100 bings were arranged so that the rovings were in close contact with each other, adhered with a thermosetting resin adhesive, and wound on a bobbin to obtain a continuous long composite glass fiber base material. A cross-sectional view of this base material is shown in FIG. By the same operation, another long continuous glass fiber base material with the same bobbin wound was obtained.

A continuous glass fiber swirl mat having a width of 266 mm and a weight of 450 g / m ² was prepared, and the two composite glass fiber substrates obtained above were provided on both outsides of the mat, and the glass of each substrate was used. Set it on the conveying element of the pultrusion molding machine so that the cross side becomes the surface, and impregnate it with the unsaturated polyester resin bath. The resin-impregnated composite glass substrate can be drawn into the die set to the curing temperature of the polyester resin and shaped and heat-cured.
The apparatus was operated so that a series of steps were continuously performed, and a continuous molded article was manufactured. The layer cross-sectional view of the obtained molded product is shown in FIG. 2, and the shape cross-sectional view is shown in FIG.

The space required to prepare the glass fiber base material is to set a total of three bobbins, two bobbins for the composite glass fiber base material and one bobbin for the glass fiber swirl mat. The size of the rack is enough to save space, and it saves the indispensable work of passing many glass fiber rovings through the guides of the conveyor, and the preparation time of the equipment set for molding is conventionally reduced. It was able to be shortened significantly.

Further, the molding work can be carried out smoothly without entanglement among the rovings, there is almost no trouble at the time of molding, and a molded product having a very uniform glass content throughout can be obtained with high productivity. Was completed. Furthermore, during the molding operation, when one of the base materials is consumed and is exhausted, it is sufficient to connect a new base material to every three bobbins, which can be done in a short time, so that the productivity of the molded product can be improved. Did not fall much.

Comparative Example 1 A pultrusion molding apparatus provided with 600 roving conveyance guides (3 per roving) was used, and a glass fiber cloth and a glass fiber roving (200
This is used without adhesive bonding with a thermosetting resin adhesive,
A molded product was obtained in the same manner as in Example 1 except that the glass fiber swirl mat was used.

The space required to prepare the glass fiber base material is 200 roving bobbins, 2 glass fiber cloth bobbins, and 1 bobbin for glass fiber swirl mats, for a total of 203 spaces. The space for setting the bobbin is required, and the space is extremely wider than the space in the first embodiment. Many glass fiber rovings had to be prepared by spending a great deal of time threading the guides of the conveyor.

In addition, the roving companions were entangled with each other during the conveyance, and the molding operation could not be carried out smoothly, so that the pultrusion molding had to be carried out at a considerably slower speed than in Example 1. Attempting to obtain a molded article at the same speed as in Example 1,
The rovings were not partially parallel to the longitudinal direction of the molded product, and a molded product having a uniform glass content in the cross-sectional direction and the longitudinal direction was not obtained. Furthermore, during the molding process, when one of the materials is consumed and runs out, it is necessary to connect the materials with each time, which takes a long time, and the productivity of the molded product is extremely reduced. .

Example 2 By the same operation as in Example 1, except that only one bobbin of a continuous long composite glass fiber base material was used as it was.
A molded product was obtained.

The space required for preparing the glass fiber base material is sufficient only for the size of the frame for setting one bobbin for the composite glass fiber base material, which saves space. At the same time, it was possible to save the time and labor required for the guides of the conveyor to pass a large number of glass fiber rovings, which had been indispensable in the past, and the preparation time of the equipment set for molding could be greatly shortened compared to the past.

Further, the molding work can be carried out smoothly without the roving comrades being entangled with each other, there is almost no trouble at the time of molding, and it is possible to obtain with high productivity a molded product having a very uniform glass content throughout. Was completed. Furthermore, during the molding operation, when the base material is consumed and lost,
Since it suffices to connect one bobbin to a new base material, which can be performed in a short time, the productivity of the molded product is hardly reduced.

[0038]

In the present invention, since a specific composite fiber base material is used, it is possible to solve many drawbacks which have been important problems in the conventional pultrusion molding method. That is,
The preparation time for setting the bing on the pultrusion molding device can be shortened, and the number of roving bobbins used can be reduced, so that the roving storage space can be reduced, which reduces molding troubles, simplifies maintenance, and improves the quality of FRP molded products. It is expected that many effects will be obtained, and that it will greatly contribute to the improvement of the pultrusion molding technology.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a base material used in Example 1.

FIG. 2 is a cross-sectional view of a layer structure of a molded product obtained in Example 1.

FIG. 3 is a cross-sectional view related to the shape of the molded product obtained in Example 1.

[Explanation of symbols]

 1,1 ', 1' 'Glass fiber roving 2,2', 2 '' Glass fiber cloth 3 Glass fiber swirl mat

Claims (4)

[Claims] 1. A composite fiber base material (A) obtained by bonding a plurality of fiber rovings aligned on at least one surface of a long fiber fabric so as to be parallel to the long direction,
A method for producing a fiber-reinforced plastic molded article, which comprises impregnating a thermosetting resin bath, drawing it into a heated die, and continuously shaping and thermosetting. 2. A base material (A) and a fiber fabric (B) having a higher density than the fiber fabric in the base material (A) are used together, and the base material (B) is the center, and at least one outside thereof The production method according to claim 1, wherein the fiber base material (A) is superposed such that the fiber fabric side is the surface, and then the thermosetting resin bath is impregnated with the fiber base material (A). 3. The method according to claim 1, wherein the fiber fabric is a glass fiber fabric, and the fiber roving is a glass fiber roving. 4. The method according to claim 1, wherein the thermosetting resin is an unsaturated polyester resin.