JP2005199580A - Reinforcing material for molding fiber-reinforced resin composite, fiber-reinforced resin composite, and method for producing fiber-reinforced resin composite - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reinforcing material for molding a fiber-reinforced resin composite which is excellent in heat resistance, strength, and noise reduction effect and suitable for the cog of a synthetic resin toothed wheel used under conditions of a high temperature and a high load, the fiber-reinforced resin composite using the reinforcing material, and a method for producing the fiber-reinforced resin composite. <P>SOLUTION: After the reinforcing material composed of core-shell type composite filaments containing fibers having a pyrolysis starting temperature of at least 280°C, tensile strength of at least 3 cN/dtex, and a tensile modulus of elasticity of 40-2,000 cN/dtex is arranged in a mold, a liquid resin is injected into the mold to impregnate the reinforcing material and molded. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a reinforcing material for molding a fiber-reinforced resin composite, a fiber-reinforced resin composite using the reinforcing material, and a method for producing the fiber-reinforced resin composite. Using a reinforcing material composed of a core-sheath type composite yarn containing fibers having a tensile strength of 3 cN / dtex or higher and a tensile elastic modulus in the range of 40 to 2000 cN / dtex. The present invention relates to a fiber reinforced resin composite and a method for producing the same.

  Conventionally, metal materials such as steel have been common as gear materials, especially in applications that require high loads. Recently, tooth parts have been recently developed for the purpose of eliminating noise and reducing weight when gears mesh. The use of a fiber reinforced resin composite is being studied.

  As a reinforcing material for such a fiber reinforced resin composite for forming a tooth part, for example, as shown in JP-A-2002-273729, a fiber having high strength and high elastic modulus is used, but it is too high. When fibers having high strength and high elastic modulus are used, there is a problem that it is difficult to cut teeth.

  In order to solve such problems, Japanese Patent Application Laid-Open No. 2001-295913 uses a blended yarn of high-strength fibers (para-aramid fibers) and organic fibers having a lower strength than the fibers, Reinforcing material that achieves both machinability and Japanese Patent Application Laid-Open No. 7-113458 mixed high-strength para-type aromatic polyamide fibers and meta-type aromatic polyamide fibers excellent in machinability. Non-woven reinforcing materials are disclosed, but in these reinforcing materials, high-strength fibers and lower-strength fibers are uniformly mixed in the form of short fibers, so there is a demand for higher-strength reinforcing materials. There was a problem that could not respond to.

JP 2002-273729 A JP 2001-295913 A JP-A-7-113458

  An object of the present invention is to provide a reinforcing material for molding a fiber reinforced resin composite which is excellent in heat resistance, strength and noise reduction effect, and suitable for a tooth portion of a synthetic resin gear used under high load and high temperature conditions. The object is to provide a fiber-reinforced resin composite using a reinforcing material and a method for producing the same.

  As a result of intensive studies to achieve the above object, the present inventors have determined that a desired fiber-reinforced resin composite can be obtained when a reinforcing material is constituted from a core-sheath type composite yarn, and the present invention has been achieved. did.

  Thus, according to the present invention, (1) a reinforcing material for molding a fiber reinforced resin composite obtained by impregnating a reinforcing material with a resin, wherein the reinforcing material has a thermal decomposition starting temperature of 280 ° C. or higher and a tensile strength of A reinforcing material for molding a fiber-reinforced resin composite, characterized in that it is composed of a core-sheath type composite yarn containing fibers having a tensile modulus of elasticity of 3 to cN / dtex and a tensile modulus of 40 to 2000 cN / dtex, (2) A fiber-reinforced resin composite obtained by impregnating a reinforcing material with a resin, wherein the reinforcing material has a thermal decomposition starting temperature of 280 ° C. or higher, a tensile strength of 3 cN / dtex or higher, and a tensile modulus of 40 A fiber-reinforced resin composite comprising a core-sheath composite yarn containing fibers in a range of ˜2000 cN / dtex, (3) a thermal decomposition starting temperature of 280 ° C. or higher, and a tensile strength of 3 cN / dtex or more, and A reinforcing material composed of a core-sheath type composite yarn containing fibers having a tensile modulus of elasticity in the range of 40 to 2000 cN / dtex is placed in the mold, and then a liquid resin is injected into the mold to form the reinforcing material. There is provided a method for producing a fiber reinforced resin composite, which is characterized by impregnating and then molding.

  According to the present invention, a reinforcing material for molding a fiber reinforced resin composite excellent in heat resistance, strength, and noise reduction effect can be obtained, so that it can be used for synthetic resin gears used under high load and high temperature conditions. Can be suitably used.

  Hereinafter, the present invention will be described in detail. The reinforcing material of the present invention is composed of a core-sheath type composite yarn containing fibers having a thermal decomposition temperature of 280 ° C. or higher, a tensile strength of 3 cN / dtex or higher, and a tensile elastic modulus in the range of 40 to 2000 cN / dtex. ing.

  That is, considering the molding temperature of the fiber reinforced resin composite and the long-term use in a high temperature atmosphere, it is essential that the thermal decomposition temperature of the fiber is 280 ° C. or higher.

  Further, when the fiber has a tensile strength of less than 3 cN / dtex, it cannot withstand a high load during high-speed rotation, and the fiber-reinforced resin composite is damaged or sufficient durability cannot be obtained.

  Furthermore, when the elastic modulus of the fiber is less than 40 cN / dtex, the fiber deforms when an instantaneous load is applied. On the other hand, when the elastic modulus exceeds 2000 cN / dtex, the noise reduction effect is inferior. The tensile elastic modulus of the fiber needs to be in the range of 40 to 2000 cN / dtex. By using a fiber having such an elastic modulus, noise or vibration generated when the gear meshes can be significantly reduced.

  It is important that the reinforcing material of the present invention is composed of a core-sheath type composite yarn containing the fiber. Here, the core-sheath type composite yarn means a composite yarn in which fibers having relatively high strength are mainly arranged in the core portion and fibers having lower strength are mainly arranged in the sheath portion.

It is necessary that the core yarns in the composite yarn are arranged substantially linearly. This is because, when the core yarns are arranged in a curved line, when the tensile load is applied to the composite yarn, the tensile force does not work until the curved fibers are linearly aligned. This is because even if the elastic modulus is high, the function is not exhibited as a composite yarn, and the dimensional stability of the reinforcing material is lost. Here, “substantially linear” refers to a state in which 70% or more of the number of constituent single fibers is arranged at an angle of 45 ° or less with respect to the yarn axis.
Therefore, in the present invention, the core yarn is preferably a long fiber yarn.

  The sheath yarn in the composite yarn is preferably partially entangled with the core yarn so as not to be detached from the core yarn. Here, when the sheath yarn is partially entangled with the core yarn, when the composite yarn is cut into a length of about 2 cm, the single fiber constituting the core yarn cannot be easily pulled out. Say. In this entanglement, the core yarn and the sheath yarn are both long fibers and may be partially entangled, but the sheath yarn is a spun yarn such as spun yarn, coarse yarn, check yarn, etc. More preferably, it is entangled with the core yarn by the fuzz of origin.

  The short fiber length in the case of using short fibers as the fibers constituting the composite yarn is preferably in the range of 15 to 90 mm. When the short fiber length is less than 15 mm, not only fiber opening becomes difficult, but also the fiber entanglement decreases, so the strength of the reinforcing material decreases, and the durability and impact resistance of the fiber reinforced resin composite decrease. There are things to do. On the other hand, when the short fiber length is longer than 90 mm, the uniformity at the time of opening is hindered, and therefore, the variation in strength of the reinforcing material becomes large, which is not preferable. Moreover, when mixing a some raw material, it can also open with a well-known mixing opening machine.

  The ratio of the core portion in the cross section of the composite yarn is preferably 20% to 80%. When the ratio is less than 20%, the contribution of the core yarn to the strength of the composite yarn is reduced. On the other hand, when the ratio exceeds 80%, cutting of the teeth becomes difficult.

  The fibers used in the composite yarn include wholly aromatic polyester fibers (including high-strength polyarylate fibers), polyparaphenylene benzobisoxazole fibers (hereinafter referred to as PBO fibers), para-type aramid fibers, meta-type aramid fibers, and polyphenylenes. Examples thereof include heat-resistant synthetic fibers such as sulfide fibers (hereinafter referred to as PPS fibers), polyimide fibers, or ultrahigh molecular weight polyethylene fibers. When mechanical strength is particularly required, carbon fibers and glass fibers can also be used.

  In addition, these fibers are not limited to one type, and two or more types can be used in combination. In order to improve processability, polyester fibers are used within the range not impairing the object of the present invention. May be dispersed in a small amount.

  Although there is no restriction | limiting in particular in the single fiber fineness of the said fiber, Preferably it is 0.4-5.0 dtex. When the single fiber fineness is greater than 5.0 dtex, the rigidity of the fiber is increased, and it is difficult to obtain a uniform basis weight in the process of manufacturing the reinforcing material, and the number of single fibers per weight is reduced. As a result, the resin reinforcing effect may be reduced. Further, if the number of single fibers per unit weight is reduced, the fiber surface area is reduced and the adhesion with the resin is hindered, so that the durability of the gear may be lowered.

  On the other hand, when the single fiber fineness is less than 0.4 dtex, the strength of the reinforcing material is lowered because the strength of the single fiber is lowered, and the durability of the fiber-reinforced resin composite may be lowered. Further, it is not preferable because the fiber is easily cut or entangled in the manufacturing process of the reinforcing material, and the productivity is lowered.

  Among the above fibers, the fibers to be arranged on the core yarn are aromatic polyester fibers, polyparaphenylene benzobisoxazole fibers, para type aramid fibers, etc., and have a tensile strength of 20 cN / dtex or more and a tensile elastic modulus of 450 to A fiber in the range of 1100 cN / dtex is preferably exemplified. If the fiber has a tensile strength of 20 cN / dtex or more, the composite yarn has sufficient strength, and if the tensile elastic modulus is 450 to 1100 cN / dtex, it can withstand the momentary stress applied to the core yarn. And the noise reduction effect is sufficient.

  On the other hand, fibers having a tensile strength in the range of 3 to 10 cN / dtex, such as meta-type aramid fibers and PPS fibers, are preferable as the fibers to be arranged as the sheath yarn.

  Furthermore, in order to improve the impregnation property between the reinforcing material and the resin, various surfactants are attached to the above fibers, and the oil agent and the scouring agent (both of which are interfaced originally) It is possible to improve the impregnation property with the resin by leaving a trace amount of the compound containing an activator) without thoroughly washing.

  The composite yarn can be used as a reinforcing material in any form such as a woven fabric or a non-woven fabric. In this case, for example, after knitting into a tubular knitted fabric, if the doughnut-shaped material is used as a reinforcing material by winding it upside down, there will be no joint that weakens the mechanical strength. Uniform strength.

  The donut shape refers to a state in which the tubular knit fabric is turned upside down or turned upside down, and may be formed into a double donut shape turned upside down or turned upside down. Or, after turning it over and making it double, it may be rolled up or turned over.

  Further, the reinforcing material may be a seamless cylindrical nonwoven fabric, and may be formed into a donut shape by being turned upside down or turned upside down, or a plurality of cylindrical nonwoven fabrics having different diameters may be stacked. Further, a normal nonwoven fabric may be cut into a slit shape and wound so as to draw a vortex around the gear bush.

  What is necessary is just to set suitably the fabric weight and thickness of the said woven fabric or a nonwoven fabric according to the diameter of a gear, the impregnation property of the resin to a reinforcing material, and the required mechanical strength.

  The method for producing the fiber reinforced resin composite of the present invention is not particularly limited, and a conventionally known method can be arbitrarily employed. For example, the composite yarn is formed into a tubular knitted fabric or a cylindrical nonwoven fabric, and these are turned over. One or a plurality of doughnut-shaped ones are arranged in a mold, and then a liquid resin is injected into the mold and impregnated into the reinforcing material.

  Here, the impregnation property of the resin to the reinforcing material is further improved by reducing the mold in advance or raising the temperature. Alternatively, the tubular knitted fabric or the cylindrical nonwoven fabric may be impregnated with a thermosetting resin and dried to be in a semi-cured state, and then placed in a mold for molding.

  In particular, when a gear is formed, the tooth portion is generally formed by mechanical cutting, but may be formed by gear-type mold forming.

  The resin impregnated into the nonwoven fabric is phenol resin, epoxy resin, polyester resin, polyamide resin, polyimide resin, polyaminoamide resin, PES (polyethersulfone) resin, PEEK (polyetheretherketone) resin, CP resin (crosslinked polyester) Examples thereof include thermosetting resins such as amides and cross-linked polyaminoamides, and thermoplastic resins, and these can be used as one kind or a mixture of one or more kinds.

  Hereinafter, the present invention will be described in more detail with reference to examples. The test conditions and measurement methods used in the examples are as follows.

(1) Thermal decomposition start temperature of fiber It measured using the thermal analyzer (Rigaku Corporation TAS-200).

(2) Tensile strength of fiber It measured based on JIS L-1013.

(3) Tensile modulus of fiber Measured based on JIS L-1013.

(4) Mechanical strength of fiber reinforced resin composite A gear is molded, a test piece of a certain size is produced from the gear, and a 3.5 mm diameter pin gauge is formed between teeth at a speed of 2.5 mm / min. The indentation strength was measured when the teeth were broken. The destruction of the tooth occurred due to a crack in the tooth base.

(5) Noise of fiber reinforced resin composite A gear is molded, and the gear is meshed with an iron gear (material: JIS S45C) and rotated in lubricating oil at 130 ° C., and the noise generated when the gears mesh with each other is sensory-determined. did. A low noise level was indicated by ○, and a high level noise was indicated by ×.

(6) Cutting property of fiber reinforced resin composite After forming a gear, cutting was performed in order to form a tooth portion, and the cutting portion was observed and determined with a microscope. Judgment criteria are ○ when the cutting surface is uniform, and × when it is difficult to cut or the fibers on the cutting surface are not cut cleanly and protruded into the cutting surface in a multiple beard shape. .

[Example 1]
110dtex para-aramid fiber (Teijin Techno Products Co., Ltd .: Technora) is used as the core yarn, and 40th meta-aramid fiber (Teijin Techno Products Co., Ltd .: Conex) is used for the spinning process. The core-sheath type composite yarn of 20th was obtained by the core span method.

  After the composite yarn is made into a tubular knitted fabric, the tubular knitted fabric is wound upside down from one end to be formed into a donut shape, placed in a mold heated to about 200 ° C., and the polyaminoamide resin is placed under reduced pressure. The reinforcing material was injected and impregnated, and the impregnated resin was cured to form a fiber reinforced resin composite.

  Next, the composite was machined to form teeth, and a fiber reinforced resin composite gear was obtained.

  The thermal decomposition starting temperature, tensile strength, and tensile modulus of the fiber used for manufacturing the gear are shown in Table 1, and the mechanical strength, noise, and machinability at the time of gear molding of the obtained fiber reinforced resin composite gear. Is shown in Table 2.

[Example 2]
In Example 1, 110dtex check-processed yarn (Teijin Techno Products Co., Ltd .: GTN) obtained by check-cutting 1560 dtex para-type aramid fiber (Teijin Techno Products Co., Ltd .: Technora) as the core yarn. ) Was used in the same manner as in Example 1, except that

  The thermal decomposition starting temperature, tensile strength, and tensile modulus of the fiber used for manufacturing the gear are shown in Table 1, and the mechanical strength, noise, and machinability at the time of gear molding of the obtained fiber reinforced resin composite gear. Is shown in Table 2.

[Example 3]
In Example 1, 110 dtex wholly aromatic polyester fiber (Kuraray Co., Ltd .: Vectran) was used as the core yarn.

  The thermal decomposition starting temperature, tensile strength, and tensile modulus of the fiber used for manufacturing the gear are shown in Table 1, and the mechanical strength, noise, and machinability at the time of gear molding of the obtained fiber reinforced resin composite gear. Is shown in Table 2.

[Example 4]
In Example 1, it carried out like Example 1 except having used 110 dtex polyparaphenylene benzobisoxazole fiber (Toyobo Co., Ltd .: Zylon-HM) as a core thread.

  The thermal decomposition starting temperature, tensile strength, and tensile modulus of the fiber used for manufacturing the gear are shown in Table 1, and the mechanical strength, noise, and machinability at the time of gear molding of the obtained fiber reinforced resin composite gear. Is shown in Table 2.

[Example 5]
A fiber reinforced resin composite gear was produced in the same manner as in Example 1 except that 40th PPS fiber spun yarn (Toray Industries, Inc .: Torcon) was used as the sheath yarn in Example 1.

  The thermal decomposition starting temperature, tensile strength, and tensile modulus of the fiber used for manufacturing the gear are shown in Table 1, and the mechanical strength, noise, and machinability at the time of gear molding of the obtained fiber reinforced resin composite gear. Is shown in Table 2.

[Comparative Example 1]
In Example 1, as a composite yarn, a meta-aramid short fiber having a single fiber fineness of 2.2 dtex (Teijin Techno Products Co., Ltd .: Conex) and a para-aramid short fiber having a single fiber fineness of 1.7 dtex (Teijin Techno) This was carried out in the same manner as in Example 1 except that 20th spun yarn obtained by blending products (Technology Co., Ltd .: Technora) was used.

  The thermal decomposition starting temperature, tensile strength, and tensile modulus of the fiber used for manufacturing the gear are shown in Table 1, and the mechanical strength, noise, and machinability at the time of gear molding of the obtained fiber reinforced resin composite gear. Is shown in Table 2.

[Comparative Example 2]
In Example 1, instead of the composite yarn, Example 1 except that a 40-count spun yarn of a meta-type aramid short fiber (Teijin Techno Products Co., Ltd .: Conex) having a single fiber fineness of 2.2 dtex was used. It carried out like.

  The thermal decomposition starting temperature, tensile strength, and tensile modulus of the fiber used for manufacturing the gear are shown in Table 1, and the mechanical strength, noise, and machinability at the time of gear molding of the obtained fiber reinforced resin composite gear. Is shown in Table 2.

  According to the present invention, a reinforcing material for molding a fiber reinforced resin composite excellent in heat resistance, strength, and noise reduction effect can be obtained, so that it can be used for synthetic resin gears used under high load and high temperature conditions. Can be suitably used.

Claims (7)

  A reinforcing material for molding a fiber reinforced resin composite obtained by impregnating a reinforcing material with a resin, wherein the reinforcing material has a thermal decomposition starting temperature of 280 ° C. or higher, a tensile strength of 3 cN / dtex or higher, and a tensile elastic modulus. Is composed of a core-sheath type composite yarn containing fibers in the range of 40 to 2000 cN / dtex, and a reinforcing material for molding a fiber-reinforced resin composite.   The reinforcing material for molding a fiber-reinforced resin composite according to claim 1, wherein the core yarn is a long fiber yarn.   The reinforcing material for molding a fiber-reinforced resin composite according to claim 1 or 2, wherein the sheath yarn is a spun yarn.   4. The fiber-reinforced resin composite according to claim 1, wherein the core yarn is at least one fiber selected from the group consisting of wholly aromatic polyester fibers, polyparaphenylene benzobisoxazole fibers, and para-type aramid fibers. Reinforcing material for molding.   The reinforcing material for molding a fiber-reinforced resin composite according to any one of claims 1 to 4, wherein the sheath yarn includes a meta-type aramid fiber and / or a PPS fiber.   A fiber-reinforced resin composite obtained by impregnating a reinforcing material with a resin, wherein the reinforcing material has a thermal decomposition starting temperature of 280 ° C. or higher, a tensile strength of 3 cN / dtex or higher, and a tensile modulus of 40 to 2000 cN / A fiber-reinforced resin composite comprising a core-sheath type composite yarn containing fibers in the range of dtex.   A reinforcing material composed of a core-sheath type composite yarn including a fiber having a thermal decomposition starting temperature of 280 ° C. or higher, a tensile strength of 3 cN / dtex or higher, and a tensile elastic modulus in the range of 40 to 2000 cN / dtex is gold. A method for producing a fiber-reinforced resin composite, comprising: placing a mold in a mold, pouring a liquid resin into the mold, impregnating the reinforcing material, and then molding the mold.