JP3345661B2 - Yarn for thermoplastic composites - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber reinforced composite yarn obtained by fiberizing a thermoplastic resin and blending the fiber with a reinforcing fiber.

[0002]

2. Description of the Related Art Thermoplastic composite yarns in which continuous reinforcing fibers and thermoplastic matrix fibers are blended are disclosed in JP-A-60-209034 and JP-A-61-130.
No. 345, for example.

However, when these conventional composite yarns are braided, the continuous reinforcing fibers are damaged due to the difference in elongation between the continuous reinforcing fibers and the thermoplastic matrix fibers and their lack of convergence. Not only is the operability significantly inferior, but when the blade is formed, spots of impregnation occur, the obtained molded body lacks toughness, and it is not possible to obtain a molded body with excellent surface condition There was a problem. In order to improve the operability, if a large amount of a surface treatment agent such as a spinning oil is applied to the fibers, the operability is improved to some extent, but the surface treatment agent causes the interface between the reinforcing fibers of the molded article and the matrix. There were problems such as low strength.

On the other hand, there is also a composite yarn in which discontinuous reinforcing fibers and thermoplastic matrix fibers are twisted in a so-called spinning process to impart bunching properties. When forming a blade using this, it is possible to ensure a considerable degree of operability. However, the physical properties of the obtained molded body cannot be satisfactory due to twisting. Further, even in the surface state, there is a problem that a so-called resin-rich portion exists because the distribution of the reinforcing fibers becomes uneven due to the twisting.

[0005] As described above, the thermoplastic composite yarn in which the reinforcing fiber and the thermoplastic matrix fiber are mixed is an effective yarn for solving the difficulty of impregnation due to the high viscosity of the thermoplastic resin. However, at present, there is no thermoplastic composite yarn that satisfies both the textile processability such as weaving and braiding properties and the physical properties of the composite obtained by molding.

[0006]

SUMMARY OF THE INVENTION The present inventors have studied various measures for imparting textile workability to these fibers, and as a result, mixed non-continuous thermoplastic matrix fibers and non-continuous reinforcing fibers. When the mixed fiber is wound and covered with the continuous thermoplastic matrix fiber, the continuous thermoplastic matrix fiber of 1% by weight or more and 10% by weight or less based on the total weight of the thermoplastic composite yarn composed of these fibers is used. By winding and coating in a state of being substantially uniformly dispersed in the yarn axis direction of the mixed fiber, the surface state becomes good, the convergence is extremely improved, and as a result, it is lightweight, tough and has excellent surface smoothness. It has been found that it is possible to provide a thermoplastic composite yarn having excellent weaving properties and braiding properties. In addition, it has been found that, when the continuous thermoplastic matrix fiber is a crimped yarn, the surface state is improved by improving the covering property, and the textile workability is further improved. The present inventors have further studied based on such knowledge, and as a result, have completed the present invention.

[0007]

That SUMMARY OF THE INVENTION The present invention is, no
A thermoplastic composite yarn (4) comprising a twisted discontinuous thermoplastic matrix fiber (1), an untwisted discontinuous reinforcing fiber (2) and a continuous thermoplastic matrix fiber (3) of the same type as (1). Te, (1) and (2) and the intermingling of 2
1% by weight based on (4) in the mixed yarn mixed at 0% or more
Not less than 10% by weight of (3) in the yarn axis direction of the mixed fiber.
Thermoplastic composites for yarns, characterized in that it is wound coated with uniform one dispersed state (4), and the above-described heat continuous thermoplastic matrix fibers (3) is characterized by comprising the crimped textured yarn It is intended to provide a plastic composite yarn (4).

[0008] The degree of mixing is defined by the following equation.

(Equation 1) N: the total number of one type of filament among the various types of filaments constituting the mixed yarn NcX: the number of groups when the one type of filament is divided into several groups X: each of the above groups In the group, the number of filaments in one specific group Also, in the above formula, 100 (NX) / (N-1)
Means a mixed state, and the smaller the X, the higher the mixed state. NcX / (N / X) means how important the filament is to the visual effect in the whole mixed yarn.

Hereinafter, the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto. FIG. 1 schematically shows a typical example of the thermoplastic composite yarn according to the present invention. A is an enlarged schematic cross-sectional view of the thermoplastic composite yarn, and B is a schematic perspective view of the thermoplastic composite yarn. The thermoplastic composite yarn (4) is formed by mixing a substantially non-twisted discontinuous thermoplastic matrix fiber (1) with a substantially untwisted discontinuous reinforcing fiber (2) into a continuous thermoplastic yarn. The matrix fiber (3) is wound and coated in a state of being substantially uniformly dispersed in the yarn axis direction of the mixed fiber. FIG. 2 schematically shows, as a comparative example of the present invention, a typical example in which the mixed fiber is wound and covered with the continuous thermoplastic matrix fiber (3) in a non-dispersed state.

The thermoplastic matrix fibers (1 or 3) used in the present invention include nylon 6 and nylon 6
And polyamide fibers such as polyethylene terephthalate and polybutylene terephthalate, polyolefin fibers such as polyethylene and polypropylene, polyetheretherketone fibers, polyphenylenesulfide fibers, polyetherimide fibers, and polycarbonate fibers. However, the thermoplastic matrix fiber (1 or 3) used in the present invention
Is not limited to the above fibers.

The reinforcing fibers (2) used in the present invention include carbon fibers, aramid fibers, glass fibers and the like. However, the reinforcing fibers (2) used in the present invention are not limited to the above fibers.

In the present invention, it is necessary that both the thermoplastic matrix fiber (1) and the reinforcing fiber (2) constituting the mixed fiber are non-twisted discontinuous fibers. This is to prevent a defect in the composite physical properties and surface condition from occurring due to the displacement of the reinforcing fibers during molding when forming a composite after forming into a textile product such as a blade or a woven fabric. That is, by using the non-twisted discontinuous fiber, it is possible to form a product having a complicated shape without difficulty.

[0013] These thermoplastic matrix fibers (1)
The average fiber length of the reinforcing fiber (2) is not particularly limited, but is preferably 50 mm or more.

These thermoplastic matrix fibers (1)
And the reinforcing fiber (2) are blended, and the blending degree is 2
It needs to be 0% or more. If the content is 20% or more, impregnation into the reinforcing fiber is performed in a short time at the time of melting, but if the degree of mixing is less than 20%, impregnation takes time and is uneconomical, and impregnation is insufficient. This is because the mechanical properties of the molded article are reduced. In addition, as a means of blending, after each continuous fiber is separately cut to obtain a sliver, the slivers are mixed and cut, a method of obtaining a mixed sliver, or a continuous fiber for reinforcement is cut. after obtaining the sliver, it was mixed with enough matrix discontinuous sliver and kneading conditions Engineering obtained by a card process,
Any means such as a method of obtaining a mixed sliver or a mixed roving may be used. Thereafter, a sliver or the like is wound and covered with a thermoplastic continuous matrix fiber.

[0015] The weight ratio of the continuous thermoplastic matrix fiber (3) for winding coating to the thermoplastic composite yarn (4) of the present invention must be not less than 1% by weight and not more than 10% by weight. It is necessary that the continuous thermoplastic matrix fiber (3) is wound and coated substantially uniformly dispersed in the yarn axis direction of the mixed fiber. This is because, for the first time, it is possible to achieve both the textile processability and the obtained composite physical properties. This will be described in detail below.

The weight ratio referred to herein is defined by the following equation. Weight ratio = {C / (A + B + C)} × 100 (%) A: Amount of discontinuous thermoplastic matrix fiber (1) (g /
m) B: amount of reinforcing fiber (2) (g / m) C: amount of continuous thermoplastic matrix fiber (3) (g / m)
m)

In the actual process, the thermoplastic composite yarn (4) is melted by applying heat and pressure to melt the discontinuous thermoplastic matrix fiber (1) and the continuous thermoplastic matrix fiber (3). Then, it is impregnated into the reinforcing fibers (2) and becomes a composite through a cooling process. Accordingly, factors that govern the physical properties and appearance of the composite include the molten state of the above two types of thermoplastic matrix fibers (1 and 3). The main role of the continuous thermoplastic matrix fiber (3) is in the textile processability. That is, the blade or fabric,
It can be obtained without damaging the reinforcing fiber (2) and without scattering or disturbing the orientation state. Further, the reinforcing fiber (2) is cut into a predetermined shape as a material to be subjected to molding, and is preliminarily shaped (for example, into a mold or the like). Is to be made satisfactorily. Once the pre-shaping has been performed, it is important that in the subsequent so-called forming step, the melting is as smooth as possible and no trace of the wound coating is left. Mainly 2 if traces of wound coating remain
Causes two drawbacks. One is the presence of a resin-rich portion. Needless to say, the presence thereof not only impairs the surface appearance of the obtained molded article, but also deteriorates the mechanical properties of the molded article. The other is the lack of physical properties between the fiber bundles because the restraining force of the continuous thermoplastic matrix fibers (3) worked during molding and the dispersion between the reinforcing fibers (2) was insufficient. In order to avoid these drawbacks, it is necessary that the weight ratio of the continuous thermoplastic matrix fiber (3) is 10% by weight or less, while the weight ratio is 1% by weight or more in order to satisfy the above-mentioned textile processability. It is necessary to be.

Further, in order to improve the textile processability, it is necessary to wind and coat the continuous thermoplastic matrix fibers (3) in a state of being substantially uniformly dispersed in the yarn axis direction of the mixed fiber. is there. As a method of substantially uniformly dispersing, the continuous thermoplastic matrix fiber (3) can be spread by an electric fiber opening device, and then superposed on the mixed fiber and supplied to an oscillating apron roller.
It is not limited to this method.

It is more preferable that the continuous thermoplastic matrix fiber (3) is a crimped yarn. After the continuous thermoplastic matrix fiber (3) is preliminarily crimped, such as false twist crimping, the mixed fiber is wound and coated, so that coatability is improved and textile workability is further improved. To do that.

As a surface treating agent for the thermoplastic matrix fiber, a so-called spinning oil is generally used in order to maintain the fiber production process and the post-processability. However, this type of treating agent inhibits the adhesive force between the reinforcing fiber of the composite and the matrix interface, and is therefore preferably not used as much as possible.

In the present invention, the weight ratio of the reinforcing fiber (2) to the thermoplastic composite yarn (4) is not particularly limited, but is preferably in the range of 30 to 80%.

[0022]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

Embodiment 1 FIG. Nylon 6 fiber was used as the discontinuous thermoplastic matrix fiber, and carbon fiber was used as the discontinuous reinforcing fiber. Both fibers were untwisted and the average fiber length was 100 mm. These denier yarns are used as continuous thermoplastic matrix fibers for winding coating at 70 denier /
Twenty-four nylon 6 filaments were spread and wound and coated in a state of being substantially uniformly dispersed in the yarn axis direction to prepare a thermoplastic composite yarn. The method of preparation was to pull each of the nylon 6 fibers and carbon fibers used in the above-mentioned mixed fiber, to obtain slivers, and then to mix the slivers with a drawing machine and apply draft to obtain a predetermined mixed sliver. . The weight of the mixed sliver was 536 selenium / 6 yards. After the nylon 6 filament for winding coating was spread by an electric fiber opening device, the mixed sliver was superimposed and supplied to an oscillating apron roller to be wound-coated to obtain a thermoplastic composite yarn of Nm 1.7. The weight ratio of the carbon fiber to the thermoplastic composite yarn was 59 wt%, the weight ratio of the nylon 6 filament for winding coating was 1.5%, and the degree of mixing of the untwisted mixed fiber was 65%. there were.

Using the thermoplastic composite yarn thus obtained, a 32-layer blade having an angle of 30 ° and an inner diameter of 20 mm was prepared with a 32 hit circular knitting machine. At the time of braiding, the outer circumference of the mandrel was covered with a silicon tube, and after braiding, the blade was removed from the mandrel together with the blade.

The blade is subjected to internal pressure forming to a thickness of 0.8 mm.
A hollow pipe was obtained. The molding condition at that time is pressure 15kg
/ Cm ² , temperature 255 ° C., and retention time 20 minutes. The obtained hollow pipe was excellent in surface properties, had no resin-rich portion, and was a good pipe. Table 1 shows the characteristics of this pipe.
Shown in

[0026]

[Table 1]

Embodiment 2 FIG. A yarn for thermoplastic composite was prepared in the same manner as in Example 1. However, nylon 6 filament of 210 denier / 48 filaments was used as the continuous thermoplastic matrix fiber for winding coating. Therefore, the weight ratio of the nylon 6 filament for winding coating was 3.6%. The yarn count of the thermoplastic composite yarn was Nm 1.8. A hollow pipe was formed from the composite yarn in the same manner as in Example 1. The obtained hollow pipe was a good pipe with almost no resin-rich portion. Table 1 also shows the characteristics of this pipe.

Embodiment 3 FIG. Using the thermoplastic composite yarn prepared in Example 1, the basis weight, length and weft were 15 /
An inch fabric was made. This fabric is placed in a mold at a temperature of 25
Pressing was performed under the conditions of 0 ° C., a pressure of 10 kg / cm ² , and a holding time of 10 minutes, and then cooled and taken out of the mold to form a flat plate. The weaving property of the thermoplastic composite yarn used was good, and the flatness of the flat plate after molding was also good. Table 1 also shows the characteristics of the flat plate.

Embodiment 4 FIG. A thermoplastic composite yarn was prepared in the same manner as in Example 1. However, as a continuous thermoplastic matrix fiber for wound coating, 70 denier / 2
A four-filament nylon 6 filament false twisted crimped yarn was used. The obtained thermoplastic composite yarn has excellent surface covering properties, and is subjected to braiding and molding under the same conditions as in Example 1. As a result, a good pipe excellent in both braiding properties and surface properties is produced. I was able to. Table 1 also shows the characteristics of this pipe.

Comparative Example 1 A mixed fiber and a blade were prepared in the same manner as in Example 1. However, one nylon 6 filament of 70 denier 24 filaments was used without opening as a continuous thermoplastic matrix fiber for winding coating. Using a hollow spindle for wound coating, S
Yarns for thermoplastic composites were wound in only one direction. Therefore, the weight ratio of C was 1.5%. This mixed fiber has poor braiding properties, carbon fibers are damaged and cut during braiding, and the working environment is remarkably deteriorated, and the obtained blade has a very large surface condition and has a disordered fiber arrangement. Was something. Therefore, making a hollow pipe was abandoned.

Comparative Example 2 In the same manner as in Example 1, a mixed fiber, a blade and a hollow pipe were produced. However, the degree of blending of the blended yarn was 12%. In this mixed fiber, carbon fibers were damaged or cut during braiding, but could be used as a blade. Using the blade, a hollow pipe was formed under the same conditions as in Example 1. The resulting pipe had imperfectly impregnated portions and poor surface properties. Table 1 also shows the characteristics of this pipe.

Comparative Example 3 In the same manner as in Example 1, a mixed fiber, a blade and a hollow pipe were produced. However, two nylon 6 filaments of 300 denier and 60 filaments are used as the continuous thermoplastic matrix fiber for winding coating, and one is wound in the S direction and the other is wound in the Z direction using a hollow spindle. Thus, a thermoplastic composite yarn was prepared. The number of windings was also set to 180 T / M. Therefore, the weight ratio of the continuous thermoplastic matrix fiber for the winding coating was 16%. Although the thermoplastic composite yarn had good braiding properties, the yarn was generally hard and lacked flexibility. Molding was performed using the blade. However, the continuous thermoplastic matrix fiber for winding coating had too high a binding force, so that a large number of resin-rich portions were formed on the surface of the hollow pipe and were not practical.

Comparative Example 4 An attempt was made to produce a woven fabric similar to that of Example 3 using the thermoplastic composite yarn prepared in Comparative Example 1, but the drop of carbon fibers of the warp was severe, and weaving was abandoned.

Comparative Example 5 A fabric similar to that of Example 3 was produced using the thermoplastic composite yarn produced in Comparative Example 2. Although the carbon fiber was damaged and cut, the fabric could be made. Example 2 using the woven fabric
A flat plate was prepared under the same conditions as in the above, however, due to insufficient fiber mixing, a portion of impregnation failure was found.

Comparative Example 6 An attempt was made to obtain a woven fabric similar to that of Example 3 using the thermoplastic composite yarn prepared in Comparative Example 3, but the density of the woven fabric was set to 1 because the rigidity of the yarn was too high.
It could not be increased to more than one wire / inch. The woven fabric was molded under the same molding conditions as in Example 2. However, due to the strength of the binding force of the continuous thermoplastic matrix fiber for winding coating and the low density, a flat plate having a large number of resin-rich portions was found. Did not get.

[0036]

Industrial Applicability The yarn for thermoplastic composite of the present invention is useful for forming a thermoplastic composite which is lightweight, tough, and excellent in surface smoothness. Therefore, after forming into a blade, a woven fabric, a knitted fabric or a multi-axial laminated fabric, it can be applied to a considerable range of forming methods such as internal pressure forming, lay-up forming, press forming, deep drawing forming, and the effect is extremely large. It is.

[Brief description of the drawings]

FIG. 1 is an example of a schematic view of a yarn for thermoplastic composite of the present invention.

FIG. 2 is an example of a comparative example of the present invention (a continuous thermoplastic matrix fiber wound and coated in a non-dispersed state).

[Explanation of symbols]

 A: Cross-section of thermoplastic composite yarn of the present invention B: Part of thermoplastic composite yarn of the present invention C: Cross-section of thermoplastic composite yarn of comparative example D: Part of thermoplastic composite yarn of comparative example 1: discontinuous thermoplastic matrix fiber for blended yarn 2: discontinuous reinforcing fiber for blended yarn 3: continuous thermoplastic matrix fiber for wound coating 4: yarn for thermoplastic composite of the present invention 5: comparison Example thermoplastic composite yarn

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-247761 (JP, A) JP-A-1-133721 (JP, A) JP-A-62-135537 (JP, A) JP-A-1- 266231 (JP, A) JP-A-2-133632 (JP, A) JP-A-2-308824 (JP, A) JP-A-6-107808 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) B29B 11/16 B29B 15/08

Claims (2)

(57) [Claims] 1. A thermoplastic composite yarn comprising a non -twisted non-continuous thermoplastic matrix fiber, a non-twisted non-continuous reinforcing fiber, and a continuous thermoplastic matrix fiber of the same type as the non-continuous thermoplastic matrix fiber. a continuous thermoplastic matrix fibers and non-continuous reinforcing fibers combined filament yarn was mixed fiber in the combined filament of 20% or more, 1 to 10 wt% of said continuous thermoplastic matrix with respect to the thermoplastic composite for yarns fibers, thermoplastic composites for yarns, characterized in that it is wound covered while equalizing one dispersed in the yarn direction of該混yarn. 2. The thermoplastic composite yarn according to claim 1, wherein the continuous thermoplastic matrix fiber comprises a crimped yarn.