JPS58193117A - Prepreg and preparation thereof - Google Patents

Abstract

PURPOSE:To obtain a prepreg agreeing with the direction of stress given to an FRP product by arranging fibers in the prepreg nearly in parallel and bending part or all of the fibers, etc. CONSTITUTION:Fibrous threads are arranged in a prepreg in parallel with each other, straight or bent parts are provided to the lengthwise direction of the prepreg (b) or the whole body is bent (c). Or, the width of the prepreg is changed to the lengthwise direction of the prepreg (d) or the width of the prepreg is not only changed but bent to the lengthwise direction of the prepreg (e). Resin part 2 is developed on a mold releasing sheet 3 and the fibrous threads 1 are enlarged in width and moved by guides 4, 4' and attached by the compressor 5 on to the resin part to prepare such prepreg.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a unidirectional prepreg having a bent portion or curvature and a method for manufacturing the same.

The manufacturing method for fiber-reinforced plastics (hereinafter referred to as FRP) involves making the resin component into a liquid state using a solvent or heating, adding a curing agent, additives, etc. as desired, and then using prepreg, which is impregnated into a fabric (cloth). There are known ways to do this. As the fiber material for such prepregs, it is common to use a fabric woven by a normal method, but if you want to make the most of the mechanical performance of the fiber, it is necessary to use a large number of fiber threads. A so-called unidirectional prepreg is known, which is arranged in parallel and impregnated with a resin component in this state. In this type of unidirectional prepreg, in the longitudinal direction of the prepreg,
Generally, all threads or fibers are arranged in parallel in a straight line.

On the other hand, the stress applied to the FFtP product may not necessarily be distributed in a straight line. In such cases, conventionally, the unidirectional prepreg is appropriately cut and the fibers are oriented in the direction in which the stress is generated, thereby making the direction of the stress coincide with the orientation axis of the fibers. However, in such a method (cutting and splicing), the fibers are cut at the spliced portion, resulting in a decrease in strength at this portion. Therefore, since the prepregs are overlapped and seamed, the thickness of the seamed portion is doubled, resulting in a thicker prepreg.

The present invention provides a state in which each fiber thread is parallel to the longitudinal direction of the prepreg, and the fiber thread is bent over a part or the entire length of the prepreg, and/or a state in which the fiber threads are bent in the longitudinal direction of the prepreg. It is a prepreg in which the width varies and each fiber thread is arranged and fixed in a straight line or in a partially or entirely bent state without intersecting each other.

This will be explained below with reference to the drawings.

FIG. 1 is an enlarged view showing the arrangement of fiber threads of the prepreg. In the conventional unidirectional prepreg, as shown in Figure 1(a), the fiber threads (1) are arranged in the longitudinal direction of the prepreg (
) are all oriented parallel to each other. On the other hand, examples of the prepreg of the present invention include the following.

As shown in FIG. 1(b), the fiber threads are parallel to each other in the longitudinal direction of the prepreg, and the prepreg has straight portions and bent portions in the longitudinal direction of the prepreg. 1st
As shown in Figure (C), each fiber thread is parallel to each other, but the entire prepreg is bent with respect to the longitudinal direction of the prepreg. As shown in FIG. 1(d), the width of the prepreg changes in the longitudinal direction of the prepreg, but the fiber threads do not intersect with each other and are in a straight line.

As shown in FIG. 1(e), a prepreg in which the width of the grip preg changes in the longitudinal direction of the prepreg, but the fiber threads do not intersect with each other and are bent in the longitudinal direction of the prepreg.

Furthermore, it is a prepreg obtained by combining any two or more of FIG. 1(b), (C), (d), and (0).

When manufacturing FRP using the prepreg of the present invention, reinforcing fiber threads, which are strength members, can be arranged according to the stress diagram generated in the structure, and the fiber threads can be arranged most effectively. Available.

The prepreg of the present invention can be manufactured by the following method.

As shown in Figure 2, the resin component (hereinafter referred to as "IJ Lux resin") (2) constituting the prepreg is spread on release paper (6), and one or many fiber threads (1) are guided (4, 4'
), and while moving, paste it onto the matrix resin (2) using the plenosaur (5). At this time, the fiber thread (1), the guide (4, 4') and the Pretsser number) are
The prepreg of the present invention can be manufactured by moving the fibers on the resin plane according to the trajectory to be oriented.

In this method, the matrix resin used preferably has adhesive properties, and unsaturated polyester, epoxy, phenol, vinyl ester resins, etc. can be used. If the material does not have tackiness at room temperature, tackiness can be imparted by adding a solvent, heating, or the like.

If the matrix resin constituting the prepreg is solid at room temperature and does not have adhesive properties, such as polyester, nylon, or polycarbonate resin, the yarn locus can be fixed by roughening its surface by sanding, etc. It can be easily done. Alternatively, the fiber thread may be impregnated with a solvent for the matrix resin and then attached to the resin.

As shown in FIG. 3, it is further effective for fixing the orientation locus that the matrix resin (2) has a curved surface that is convex with respect to the surface to which the fiber threads (1) are attached.

In the above manufacturing method, for example, as shown in FIG. Heat it so that the guide (4)
by appropriately moving the fiber threads (1) in a direction perpendicular to the plane of the paper in conjunction with the rotation of the rotating drum (6) so as to have a predetermined orientation locus, and pressing the fiber threads (1) sequentially onto the resin surface with a presser (5). Figure 4 (Rotating drum (6) as shown in bl)
Matrix resin (2) placed on top, fiber thread (
1) can be oriented with an arbitrary trajectory.

According to the method of the present invention, it is possible to manufacture a prepreg having a bent portion or a change in width in a part or the entire length of the prepreg by arbitrarily taking an orientation locus. Further, by providing a matrix resin layer on an endless belt and simultaneously aligning and fixing a large number of yarns necessary to form a predetermined width of the prepreg, an infinite length prepreg can be obtained.

There is a method called filament winding as a method for winding yarn around a rotating trim. This method involves impregnating the fibers with a viscous resin, winding them around a rotating body and cutting them to create a flat prepreg, and wrapping the fibers around a rotating body and applying resin from above. There is a way to do it. However, in all of these methods, when cut, the fiber threads are oriented in a straight line, have no bent portions, and generally cross each other. Furthermore, in the conventional filament winding method, since the fibers are impregnated with resin, the resin viscosity is low and is not sufficient to fix the orientation locus.

Another method for obtaining the prepreg of the present invention will be explained with reference to FIG. A resin layer constituting the prepreg is placed on a three-dimensional frame shown in the hexagonal method in Fig. 5, and this three-dimensional frame is rotated around the Y axis parallel to the edges Q, P, and H to form a single fiber thread. When winding one after another to a predetermined width; or when multiple fiber threads are wound to a predetermined width, the winding locus of the thread will be parallel to Y', and the prepreg obtained by cutting at the edge P of the three-dimensional frame will be Similar to the conventional unidirectional prepreg, all fiber threads are parallel to the longitudinal direction of the prepreg. However, if the rotational axis The bending points correspond to the edges P, Q, and H, respectively, and a prepreg having an angle of θ at the bending point can be obtained.

In addition, as shown in Fig. 6, after winding fiber threads around a cylinder, the fiber threads of the prepreg obtained by cutting along the straight line OP on the cylinder are all parallel to the longitudinal direction of the prepreg. When the rotation axis X is provided at an angle with respect to the locus Y' or its rotation axis Y, a sinusoidal prepreg having an amplitude W can be obtained.

The prepreg manufacturing method explained in FIG. 5 and FIG. This is a manufacturing method in which multiple fiber threads are wrapped and fixed. For edges, planes, or curved surfaces that are not parallel to the rotational axis on the three-dimensional frame, the angle, plane, and curved surface size are determined by the arrangement locus of the threads. However, in this method, in order to ensure the fixation of the fiber threads, it is preferable that the surface of the three-dimensional frame always be convex with respect to the fixing surface of the threads.

Example 1 In FIG. 7(a), carbon fibers (1184
Pass the books through the batten (9) with a guide at an arrangement pitch of 8.2 books per 1 cIIL, and pass the books through the side frame (10, 1
The guide rod (4, 4') is fixed to the guide rod (4, 4').

4''), each carbon fiber thread is passed through the carbon fiber thread while increasing its width, and is led to a presser rod (5).

On the other hand, as shown in Figure 7(b), a curing agent and additives are added onto a plate (6) having a slightly convex shape and having mold releasability, and an epoxy resin with adjusted adhesiveness is applied. 110.
It was applied to a thickness of jil/m2, and its shape is shown in plan view (a).
Width 10. It is fan-shaped.

The carbon fiber yarn pulling tool shown in FIG. Place it from
Move the puller from end A to end B on the fan-shaped board. At this time, the thread (1) is fixed by the matrix resin.

In this way, when the T point on the extension of the presser rod (5) of the pulling tool reaches the 8th point on the board, the T point is fixed at the 8th point and the pulling tool is rotated by the bending angle θ around the 8th point. to form a bent part.

Similarly, by repeating the same operation at 81 points, 2709/m2 curved at two places as shown in Figure 7 (b) (a).
A prepreg having a weight of . This prepreg was heated at 150°C to ensure sufficient impregnation with the matrix resin.
When pressed with a hot roller press, a bent prepreg is obtained.

Example 2 One end is 10 (1 m,
The same matrix resin layer as in Example 1 with a length of 5 cWL and 1 m at the other end is provided, and the carbon fiber thread (1) is pulled from the top of the matrix resin layer (1) using the pulling tool shown in FIG. 7(A).
). At this time, the presser rod (5) of the pulling tool was perpendicular to the longitudinal direction of the matrix resin (2), and the arrangement width of the threads (1) was 10.2 cML. As the pulling tool is moved to the edge of the matrix resin with a width of 5 m, the angle between the presser rod (5) and the longitudinal direction of the matrix resin is gradually decreased at a constant rate, and the thread is removed at a position where the matrix resin width is 5 crIL. When the pulling tool is moved so that the array width of the threads is 5 cIn, the prepreg shown in Fig. 1(d) has a straight thread but the width of the prepreg changes along its longitudinal direction. get.

Example 6 The matrix resin layer shown in Example 1 was provided on the three-dimensional frame shown in FIG. The fiber threads are wound around the three-dimensional frame once so as to form a band with a width of about 10 mm. In this way, a prepreg bent to two forces of θ=2o0 as shown in FIG. 5(b) is obtained.

Example 4 A resin layer was similarly provided on the same three-dimensional frame as in Example 6, the θ angle was set to 20°, and one carbon fiber thread used in Example 1 was moved by 1.22 rnm per rotation of the three-dimensional frame. By fixing the prepreg to the resin layer, the same prepreg as in Example 3 is obtained.

[Brief explanation of drawings]

FIG. 1 is an enlarged view showing the arrangement of the fiber threads of the prepreg of the present invention, FIGS. 2 and 3 are principle diagrams of the method for manufacturing the prepreg of the present invention, and FIG. FIG. 5(a) is a side view of a rotating drum used for manufacturing prepreg, (a) is a cross-sectional view thereof, FIG. ) is an enlarged view showing the arrangement state of the fiber threads of the obtained prepreg, and FIG. 7(a) is a front view of the yarn pulling tool, (a) and (b) are longitudinal sectional views thereof, and FIG. 7(b)(a) is an enlarged view showing the arrangement state of (b) is a plan view of a board with mold release performance, and (b) is a side view thereof, where symbol (1) in the figure is a fiber thread, (2) is a matrix resin, and (6) is a release paper or a release paper. A board having mold performance, (4), (4 and (4) are guides or guide rods, (5) is a breather or presser rod, and (6) is a rotating drum. Applicant Mitsubishi Rayon Co., Ltd. Agent Patent attorney Master Masaru Kobayashi Yudai I L≧1 .7ki
4 Zo Figure 5 (0) Q (b) Day 6

Claims (1)

[Claims] 1. A state in which each fiber thread is parallel to the longitudinal direction of the prepreg, and the fiber threads are bent over a part or the entire length of the prepreg, and/or in a state in which the fiber threads are bent in the longitudinal direction of the prepreg. On the other hand, there is a prepreg in which the width of the prepreg changes and the fiber threads are arranged and fixed in a straight line or in a partially or entirely bent state without intersecting each other. 2. A matrix resin layer is provided on a flat surface or a curved surface including a cylinder, and one or more fiber threads are arranged and fixed in a predetermined curve on the matrix resin layer. Each fiber thread is parallel to the longitudinal direction of the prepreg. and the fiber threads are bent over a part or the entire length of the prepreg and/or the width of the prepreg changes with respect to the longitudinal direction of the prepreg, and each fiber thread is straight or straight without crossing each other. A method for manufacturing prepreg that is arranged and fixed in a partially or entirely bent state. 3. A matrix resin layer is provided on a three-dimensional frame having at least one edge, plane, or curved surface that is not parallel to the rotation axis, and the three-dimensional frame is rotated to form a matrix resin layer on the matrix resin layer.
Each fiber thread is parallel to the longitudinal direction of the prepreg, and the fiber threads are a part or whole of the longitudinal direction of the prepreg, characterized by wrapping and fixing one or more fiber threads in the prepreg. The width of the prepreg changes with respect to the longitudinal direction of the prepreg, and the fiber threads are arranged and fixed in a straight line or partially or entirely bent without crossing each other. Prepreg manufacturing method.