JP2001062950A - Composite material and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition material which is lightweight, and is of a sufficient breaking strength so that the progress of a breaking phenomenon is gradually underway by winding filaments helically around the longer side of a core at a specific angle and integrating both filaments and core in one piece through a foamed resin binder. SOLUTION: In the composite material 10, filaments 2 are wound around the longer side of a core 1 in a helical fashion at an angle of 30-70 deg. and both filaments 2 and core 1 are integrated in one piece through a foamed resin binder 3. The core 1 to be used is an extruded resin molding, a continuously supplied resin concrete of paper. The filament 2 to be used is for example, monofilament, fibrillated fiber or weaving yarn, and is preferably glass fiber or carbon fiber in terms of reinforcing effects. The content of the filament of a surface layer made up of a formed molding 4 in the composite material 10 is preferably 5-40 vol.%. For the foamed resin binder 3, a heat-curable foamed resin is used and especially a polyurethane foam is preferably used as it is of a high mechanical strength and is non-water absorbable due to its nature to form closed cells during foaming.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a composite material and a method for producing the same.

[0002]

2. Description of the Related Art In general, thermosetting foamed resin molded articles which are fiber-reinforced so as to be very similar in appearance to physical wood and exhibit properties equal to or higher than those of natural wood are used for building materials, structural members,
It is used as a structure, such as a water board, and especially as a sleeper.

Conventionally, a thermosetting foamed resin molded product has a core material made of a plate-like or rod-like thermosetting resin foam, which is formed by a surface material, as disclosed in, for example, JP-A-5-138797. It was sandwiched between two or more surfaces, and the surface material was made of a thermosetting foamed resin reinforced by long fibers along the longitudinal direction.

On the other hand, in fiber reinforcement by long fibers,
As a method of three-dimensionally reinforcing in the longitudinal direction, FR
There are winding techniques used for P products.

[0005]

The above-mentioned conventional composite material has a sufficient bending strength, but when a fracture stress is reached, the composite material in a direction parallel to the direction of the fibers aligned in one direction. The foamed resin surface material and the core material are broken by shearing, and the breakage occurs instantaneously, so that there is a problem in that the reliability is poor when used as a structural member.

[0006] Fiber reinforcement by winding long fibers has been established as a method for reinforcing non-foamable resins such as polyester and epoxy resin. At present, it is difficult to control the process and the fiber has been localized, so that it has not been put to practical use.

[0007] The present invention has been made in view of such problems in the conventional composite material, and an object thereof is to reduce the weight of the foamed resin by three-dimensionally reinforcing it with long fibers. A composite material having sufficient fracture strength and providing a highly reliable composite material in which the fracture mode gradually progresses, and a composite material having such excellent properties can be easily formed. It is to provide a manufacturing method of.

[0008]

In order to achieve the above object, a composite material according to claim 1 of the present invention has a foaming ratio of 1.1 to 10 comprising a foamed resin binder and long fibers on the surface of a core material.
A composite material in which double-foamed molded articles are laminated, wherein long fibers are spirally wound at an angle of 30 to 70 degrees with respect to the longitudinal direction of the core material, and the long fibers and the core material are interposed via a foamed resin binder. Are integrated.

According to a second aspect of the present invention, there is provided a method of manufacturing a composite material, wherein a long fiber resin impregnated with a foamable resin binder is impregnated into a core material at an angle of 30 to 70 degrees with respect to the longitudinal direction of the core material. , And a step of foaming the foamable resin binder. Further, the above steps are repeated a plurality of times on the outer periphery of the foamed resin binder, and the resin is guided into a mold and shaped.

Here, it is preferable to use a thermosetting resin and foamable resin particles as the foamable resin.

Applications of the composite according to the invention include, for example, synthetic sleepers.

[0012]

Next, an embodiment of the present invention will be described.
This will be described with reference to the drawings.

Referring first to FIGS. 4 and 5, a composite material (10) according to the present invention comprises a foamed resin binder on the surface of a core material (1).
A foam molded product (4) having an expansion ratio of 1.1 to 10 comprising (3) and a long fiber (2) is laminated, and the long fiber (2) extends in the longitudinal direction of the core material (1). On the other hand, it is spirally wound at an angle of 30 to 70 degrees, and is made of long fibers through a foamed resin binder (3).
(2) and the core material (1) are integrated.

Here, the core material (1) is formed by extruding a resin to continuously supply the core material in the longitudinal direction.
Examples thereof include resin concrete supplied continuously, and paper cores. The core (1) may be hollow.

The shape of the long fiber (2) is not limited as long as it has a function as a reinforcing fiber. For example, a monofilament, a fibrillated (protruding beard-like fiber) fiber, or a woven yarn may be used. Glass fibers or carbon fibers are preferred in terms of the reinforcing effect.

The proportion occupied by the long fibers (2) in the surface layer of the composite material (10) composed of the foamed molded product (4) is not particularly limited, but is preferably 5 to 40% by volume. Where the long fiber
If the ratio of (2) is less than 5% by volume, there is no reinforcing effect such as bending strength, and if it exceeds 40% by volume, for example, when the composite material (10) is used for sleepers, etc. It is not preferable because cracks may occur in parallel directions.

The foamed resin binder (3) is a thermosetting foamed resin, such as a rigid or semi-rigid polyurethane foam, a phenol foam, and a low-magnification polyester foam. In particular, polyurethane foam has a relatively high mechanical strength, and is characterized by being excellent in non-water absorption because of forming closed cells at the time of foaming, and is preferably used.

In the above, if the expansion ratio of the foamed molded article (4) is less than 1.1 times, for example, the composite material
When using (10) for sleepers, nails are difficult to drive, and composite materials
It is not preferable because it is difficult to use wood similar to (10). On the other hand, if the ratio exceeds 10 times, the compressive strength is insufficient, and the nail that has been driven cannot be held, and it is difficult to use the composite material (10) like wood, which is not preferable.

If the winding angle (θ) of the long fiber (2) is less than 30 degrees with respect to the longitudinal direction of the core material (4), the composite material
(10) Insufficient bending strength in the longitudinal direction, making it difficult to use wood-like materials.
It is not preferable because the shear strength of the side surface of (10) is insufficient, and the length of movement of one turn is long and irrational in the manufacturing method. The most preferable range of the winding angle (θ) is 4
5 to 60 degrees.

The composite material (10) according to the present invention is of a so-called batch type, in which a core material (1) has a foamable resin binder impregnated filament (2).
And may be manufactured by winding, or may be manufactured continuously.

As a continuous manufacturing method, as shown in FIGS. 1 and 2, a core material (1) fed continuously is fed to a winder.
From (11), send out many long fibers (2) to be reinforcing fibers,
While spraying foaming resin, core material is applied to the center of the long fiber (2) group.
Long fiber impregnated with foaming thermosetting resin liquid derived from (1)
(2) The group is wound continuously and spirally at an angle of 30 to 70 degrees and in a state where little tension is generated around the core material (1). The winding causes the foamable resin liquid to penetrate into the fiber bundle. In this case, the foamable resin is adhered to the long fibers (2) by a method such as spraying and infiltrating the liquid foamable resin or forcibly encouraging the resin penetration with a pressing roll or the like.

The illustrated winder (11) has a large circular orbit.
A roving ball (12) that moves around the core (1) along (13) and sends out a number of long fibers (2) that serve as reinforcing fibers, and a core along a small circular orbit (16). A spray mechanism (15) that moves around the material (1) and sprays the foamable liquid resin, and a square tubular shape for guiding the core material (1) to the center of the long fiber (2) group And a mold (14). The winder (11) is arranged in a total of three stages, and the outer shape is gradually increased by winding of the foamed resin impregnated filament (2). Are made larger in order.

Although the illustrated winder (11) has three stages, the winder (11) may of course be arranged in four or more stages. As shown in the figure, the winding of the long fiber (2) by the winder (11) is performed, for example, in the first stage counterclockwise with respect to the core material (1), in the second stage clockwise with the same, and in the third stage. The filaments overlap by changing the winding direction alternately, such as counterclockwise.
(2) It is preferable that (2) be performed so that they cross each other.

Here, in order to control the foaming of the foamable resin and facilitate the production of the composite material (10), a mixture of a liquid thermosetting resin and foamable resin beads is used as the foamable resin. It is preferable to use In this case, it is preferable that the heating temperature at the time of curing the thermosetting resin and the foaming temperature of the foamable resin beads be substantially equal, and a mixture of such a liquid thermosetting resin and foamable resin beads is used. This has the advantage that the foaming of the foamable resin beads and the winding of the long fiber (2) can be easily adjusted.

The foamable resin is a hard or semi-hard thermosetting resin solution containing a foaming agent such as a pyrolytic foaming agent, a soluble foaming agent such as chlorofluorocarbon, and a gaseous by-product during reaction curing. Examples thereof include those which form rigid polyurethane foam, phenol foam, and low-magnification polyester foam. In particular, polyurethane foam has a relatively high mechanical strength, and is characterized by being excellent in non-water-absorbing properties because it forms closed cells during foaming, and is preferably used.

It is preferable in terms of the production method to mix foamable styrene beads and foamable PVC hollow beads as foamable resin particles with the non-foamed resin to obtain a foamable resin.

Following the above three-stage winder (11), the core material (1) wound with the resin-impregnated filaments (2) is heated by a belt-type heating device incorporating a square cylindrical shaping die (5). It is led to a molding device (6) to foam and cure the foamable resin. In addition, foam is a mold
A method of not starting until guided to (5) can also be used.

FIG. 3 shows the winding state of the resin-impregnated filament (2) around the core (1) in each of the winding and resin foaming and curing steps. Here, FIG. 3A shows a state in which the first impregnated filament (2) is wound by the first winder (11), and FIG. 3 (b) shows the second state by the second winder (11). The winding state of the resin-impregnated long fiber (2) at the stage is shown, and FIG.
Third stage resin impregnated filaments by the second winder (11)
(D) shows the wound state of the resin-impregnated filament (2), and FIG. (D) shows the state after resin foaming in the shaping mold (5) of the belt-type heat forming apparatus (6). The core material (1) on which is wound is larger in size on the downstream side.

After foaming and curing of the resin, the composite material (10) is taken up by a belt type take-up machine (7), and then the composite material (10) is cut by a cutting machine.
According to (8), for example, a sleeper is cut to a predetermined length.

[0030]

Next, embodiments of the present invention will be described with reference to the drawings.

Example 1 A composite material (10) according to the present invention was manufactured using the manufacturing apparatus shown in FIGS. As the core material (1), an extruded material having a rectangular cross section made of hard polyurethane and glass fiber was used. The density of the core material (1) was 0.5 g / cm ³ .

On the other hand, the long fiber (2) has a diameter of 13 μm.
E-glass fiber roving was used in which 9000 monofilament bundles were wound up as one strand. The density of the long fiber (2) was 2.6 g / cm ³ .

As the foamed resin binder (3), a hard polyurethane resin was used. The density of this resin is
1.1 g / cm ³ . And, as the foaming thermosetting resin raw material, polydiphenylmethane diisocyanate, polyol, water (foaming agent), a foam stabilizer, and a reaction accelerator adjusted at a predetermined ratio were used. The expansion ratio of the foamed molded article (4) after shaping was 2 times.

Then, a large number of long fibers (2) serving as reinforcing fibers are sent out from the winder (11) to the continuously fed core material (1), and a group of long fibers (2) is formed while spraying a foaming resin. The core material (1) is led to the center part, and the continuous fibers are alternately and continuously surrounded by a group of long fibers (2) impregnated with the foaming thermosetting resin liquid at a 54 ° angle. (1) was wound with almost no tension. The winding and the impregnation with the foaming resin liquid were performed 12 times in an atmosphere at 25 ° C. Following the winder (11), a resin-impregnated filament (2)
The core material (1) wound with was wound into a belt-type heat forming apparatus (6) incorporating a square cylindrical shaping die (5), and was foamed and cured at a die temperature of 80 ° C.

The composite material (10) according to the present invention thus obtained.
Has a rectangular cross section, and its outer dimensions are 200 mm in height.
× 150 mm in width, and the size of the core material (1) is 160
mm × width 110 mm. Core material (1) The foamed molded article (4) of the outer layer has a thickness of 20 mm and a density of 0.8 mm.
g / cm ³ . The overall density of the composite (10) is
It was 0.63 g / cm ³ .

Example 2 The same procedure as in Example 1 was carried out, except that a rod-shaped foamed resin concrete body made of epoxy resin, vitreous foam and silica sand was used as the core material (1). The density of the core material (1) was 1.2 g / cm ³ .

On the other hand, as the long fiber (2), a pitch-based carbon fiber roving obtained by winding 9000 monofilaments having a diameter of 9 μm as one strand was used. The density of the long fiber (2) was 2.5 g / cm ³ .

A rigid polyurethane resin was used as the foamed resin binder (3). The density of this resin is
It was 0.45 g / cm ³ . As the foamable thermosetting resin raw material, a material prepared by adjusting a predetermined ratio of polydiphenylmethane diisocyanate, a polyol, a fluorocarbon-based foaming agent, 4% by volume of foamable styrene beads, and a reaction accelerator was used. In addition, the expansion ratio of beads after shaping is 3
Although it was 0 times, the expansion ratio of the whole foamed molded article (4) after shaping was 2.3 times.

Then, a large number of long fibers (2) serving as reinforcing fibers are sent out from the winder (11) to the continuously fed core material (1), and the group of long fibers (2) is formed while spraying the foaming resin. The core material (1) is led to the center part, and is continuously and alternately surrounded by a group of long fibers (2) impregnated with the foamable thermosetting resin liquid in a spiral manner at an angle of 55 degrees. (1) was wound with almost no tension. The winding and the impregnation with the foaming resin liquid were performed 16 times in an atmosphere at 25 ° C. Following the winder (11), a resin-impregnated filament (2)
Was wound and cured at a mold temperature of 90 ° C.

The composite material (10) according to the present invention thus obtained.
The external dimensions of the core material (1), the dimensions of the core material (1), and the thickness of the outer layer of the foamed molded product (4) are the same as those in Example 1 above, and the density of the foamed molded product (4) is 0.9 g / cm ³ , composite material (1
The overall density of 0) was 1.12 g / cm ³ .

Comparative Example 1 Next, for comparison, the same procedure was carried out using the core material and the long fiber of Example 1 described above.
As a raw material for the foamed resin binder, in addition to polydiphenylmethane diisocyanate, polyol, water (foaming agent), a foam stabilizer, and a reaction accelerator, a mixture prepared by mixing and adjusting 35% by weight of talc is used. The core material was arranged in the longitudinal direction of the core material with respect to the core material to be sent.

The composite material of Comparative Example 1 obtained in this manner has the same external dimensions, core dimensions, thickness of the foam molded product as the outer layer of the core material, its density, and overall density of the composite material. Of the composite material (10).

Comparative Example 2 For comparison, the same procedure was carried out using the core material of Example 2, but the difference from Example 2 was that long fibers were used.
Six bundles of carbon fiber rovings, each wound with 5000 monofilament bundles having a diameter of 9 μm as one strand, are taken as 1 bundle.
The core material fed by two winders and continuously fed alternately so that it is surrounded by a group of long fibers impregnated with a thermosetting resin solution made of unsaturated polyester in a spiral at a 52 degree angle. And wound it. The winding and the impregnation with the foaming resin liquid were performed four times in an atmosphere at 25 ° C.

The outer dimensions of the composite material of Comparative Example 2 thus obtained are the same as those of Example 2 above, but the dimensions of the core material are 172 mm in length × 142 mm in width, and the thickness of the foamed molded product is 4 mm. The density of the foamed molded article was 1.6 g / cm ³ , and the overall density of the composite material was 1.35 g / cm ³ .
cm ³ was large.

Next, the above Examples 1 and 2 and Comparative Example 1
Test pieces were prepared from the composite materials obtained in Steps 2 and 3, and the test pieces were subjected to tests for bending strength in the longitudinal direction, occurrence of nailing cracks, and nail pullout strength, and their suitability as synthetic sleepers was observed. .

Here, the test of the bending strength in the longitudinal direction was conducted according to JIS.
Performed according to -Z2101. In the nailing crack generation test, a pilot hole having a bore diameter of 23 mm and a depth of 60 mm was drilled in a test piece, and a screw nail was screwed into the test piece. The occurrence of cracking at that time was visually observed. In the nail pulling strength test, a resistance (pulling strength) at the time of pulling out a screw nail screwed into the test piece was measured. The obtained results are shown in Table 1 together with the density of each test piece.

[0047]

[Table 1] As is clear from Table 1 above, the composite materials (10) of Examples 1 and 2 according to the present invention have excellent breaking strength against bending in the longitudinal direction, no cracking due to nailing, and excellent nail pulling strength. Therefore, since the fracture mode gradually progressed, it had excellent suitability for use in, for example, synthetic sleepers and was highly reliable.

On the other hand, the composite material of Comparative Example 1 is inferior in both breaking strength and nail pull-out strength against bending in the longitudinal direction, and is difficult to use for synthetic sleepers. , Cracks due to nailing are seen,
In addition, it was heavy because of its very high density, and was unsuitable for synthetic sleepers.

[0049]

As described above, according to the present invention, the expansion ratio of the foamed resin binder and the long fiber is 1.1 to 1 on the surface of the core material.
A composite material in which a foam molded article of 0 times is laminated, wherein long fibers are spirally wound at an angle of 30 to 70 degrees with respect to the longitudinal direction of the core material, and the long fibers and the core material are interposed via a foamed resin binder. According to the composite material of the present invention, the foamed resin is three-dimensionally reinforced with long fibers, is lightweight,
Since it has a sufficient breaking strength and the breaking form gradually progresses, when used for a synthetic sleeper, for example, it has an effect of being very reliable.

Next, as described above, according to the method for producing a composite material of the present invention, a long fiber obtained by impregnating a core material with a foamable resin binder is applied to the core material at an angle of 30 to 70 degrees with respect to the longitudinal direction of the core material. A step of spirally winding at an angle, and a step of foaming a foamable resin binder, and further, repeating the above two steps a plurality of times on the outer periphery thereof, and guiding and shaping the mold into a mold. According to the method of the present invention, it is possible to form a composite material having excellent properties as described above, and there is an effect that the equipment cost is reduced without requiring a complicated apparatus.

[Brief description of the drawings]

FIG. 1 is a side view schematically showing an apparatus for carrying out a method for producing a composite material according to the present invention.

FIG. 2 is a front view of the same.

3A and 3B sequentially show a winding state of a resin-impregnated long fiber of a core material in a manufacturing process of a composite material, and FIG.
3 (b) is an enlarged sectional view taken along the line bb in FIG. 3, and FIG. 3 (c) is an enlarged sectional view taken along the line cc in FIG. 3 (d). FIG. 3 is an enlarged sectional view taken along the line dd in FIG.

FIG. 4 is a partially enlarged side view showing a winding state of a resin-impregnated long fiber around a core material in a method of manufacturing a composite material.

FIG. 5 is an enlarged sectional view of the composite material of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Core material 2 Long fiber 3 Foam resin binder 4 Foam molded object 10 Composite material 11 Winder

Claims (5)

[Claims] 1. A composite material comprising a core material and a foamed molded body comprising a foamed resin binder and long fibers having a foaming ratio of 1.1 to 10 times laminated on a surface of the core material, wherein the long fibers are arranged in a longitudinal direction of the core material. 3
A composite material characterized by being helically wound at an angle of 0 to 70 degrees and integrating long fibers and a core material via a foamed resin binder. 2. A step of helically winding a core material impregnated with a foamable resin binder at an angle of 30 to 70 degrees with respect to the longitudinal direction of the core material, and foaming the foamable resin binder. 2. The method for producing a composite material according to claim 1, further comprising the steps of: repeating the above two steps a plurality of times on the outer periphery thereof to guide and shape the inside of the mold. 3. The method for producing a composite material according to claim 2, wherein a thermosetting resin and expandable resin particles are used as the expandable resin. 4. Use of the composite according to claim 1 as a synthetic sleeper. 5. Use of a composite produced according to claim 2 or 3 as a synthetic sleeper.