JP2016107485A - Composite molding, and production method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite molding in which stress concentration is not caused due to a mold shrinkage difference between a continuous fiber-reinforced thermoplastic resin and a continuous fiber-unreinforced thermoplastic resin or a discontinuous fiber-reinforced thermoplastic resin, which is free from problems such as buckling and a crack of the continuous fiber-reinforced thermoplastic resin, in which warp deformation is not caused but adhesiveness is ensured and rigidity and weight saving are achieved efficiently, and to provide a production method of the composite molding.SOLUTION: The composite molding is obtained by: using the continuous fiber-unreinforced thermoplastic resin or the discontinuous fiber-reinforced thermoplastic resin as a core material; arranging a layer of a thermosetting resin adhesive, which causes a curing reaction with the thermoplastic resin to be used in the core material at (Tm-140°C) or lower temperature, on at least one surface of the core material; and disposing a skin material comprising the continuous fiber-reinforced thermoplastic resin on the layer of the thermosetting resin adhesive.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composite molded body obtained by laminating and integrating a skin material composed of a continuous fiber reinforced thermoplastic resin on a core material composed of a non-reinforced or discontinuous fiber reinforced thermoplastic resin composition, and particularly a method for producing the same. The present invention relates to a composite molded body suitably used for applications such as automobile interior and exterior parts excellent in rigidity and weight reduction, and a method for producing the same.

In recent years, due to increasing environmental awareness, demands for reducing CO _{2 and} reducing the weight of automobile interior and exterior parts have increased, and carbon fiber (hereinafter “CF”) may be abbreviated to achieve both high rigidity and light weight. )) Is proposed to strengthen. However, using carbon fiber entirely increases the cost and is difficult to put into practical use. On the other hand, the required strength and rigidity of automobile interior and exterior parts are not partial but very partial. In many cases, there has been an urgent need to develop an injection composite molded body by integrating a sheet-like CF base material and a resin that can be easily reinforced.

  For example, a continuous fiber reinforced thermoplastic resin plate is formed by injection molding in a state where a sheet-like CF base material, that is, a continuous fiber reinforced thermoplastic resin plate is set in a portion that needs to be reinforced in advance in the injection molding process. A composite molded body in which a discontinuous fiber reinforced thermoplastic resin composition is integrated is known (see Patent Document 1). However, since the thermal shrinkage of the continuous fiber reinforced thermoplastic resin plate is very small compared to the molding shrinkage after injection of the unreinforced or discontinuous fiber reinforced thermoplastic resin related to the present invention, the stress concentration due to the shrinkage difference. Has occurred, causing wrinkles due to distortion of the continuous fiber reinforced thermoplastic resin plate, and buckling, cracking, etc. depending on the situation. In addition, shape problems such as warp deformation due to a difference in molding shrinkage of the obtained composite molded article arise, and a desired composite molded article cannot be obtained.

JP-A-9-272134

  The object of the present invention is made in the background of the above-mentioned problems of the prior art, and stress concentration due to molding shrinkage difference between continuous fiber reinforced thermoplastic resin and non-reinforced or discontinuous fiber reinforced thermoplastic resin does not occur, Providing a composite molded body that is free of buckling and cracking of continuous fiber reinforced thermoplastic resin, that does not cause warp deformation and that has secured adhesion and that has achieved efficient rigidity and weight reduction, and a method for manufacturing the same. There is to do.

The present invention has the following configuration. That is,
(1) With respect to the thermoplastic resin (melting point: Tm (° C.)) used for the core material, which is applied to at least one surface of the core material, using a non-reinforced or discontinuous fiber reinforced thermoplastic resin as a core material (Tm -140) A composite molded body, which is integrated with a skin material composed of a continuous fiber reinforced thermoplastic resin through a thermosetting resin adhesive layer that undergoes a curing reaction at a temperature not higher than ° C.
(2) The composite molded article according to (1), wherein the discontinuous reinforcing fibers contained in the core material have a number average fiber length of 0.01 to 20 mm.
(3) The composite molded body according to (1) or (2), wherein the skin material is obtained by aligning reinforcing fibers in one direction and impregnating with a thermoplastic resin.
(4) The skin material is made of a plate-shaped skin material obtained by laminating or braiding a tape-like base material in which reinforcing fibers are aligned in one direction and impregnated with a thermoplastic resin. The composite molded body according to any one of (3).
(5) When the skin material is laminated on the core material via the adhesive layer, the thermoplastic resin (melting point: Tm (° C.)) used for the core material and the skin material is (Tm-200). The composite molded article according to any one of claims 1 to 4, wherein the composite is subjected to a curing reaction in an atmosphere of at least ° C.
(6) A non-reinforcing or discontinuous fiber reinforced thermoplastic resin is injection molded into a flat core material, and a skin material made of continuous fiber reinforced thermoplastic resin is laminated on at least one surface of the core material through an adhesive layer. In the method for producing a composite molded body, an adhesive layer is applied in a state where the surface temperature of the core material and the skin material is cooled to room temperature, and a thermoplastic resin (melting point: used for the core material and the skin material). It is a method for producing a composite molded article, wherein a curing reaction is carried out at a temperature of (Tm-140) ° C. or lower with respect to (Tm (° C.)) and then cooled to room temperature.

  According to the present invention, stress concentration due to molding shrinkage difference between continuous fiber reinforced thermoplastic resin and non-reinforced or discontinuous fiber reinforced thermoplastic resin does not occur, and problems such as buckling and cracking of continuous fiber reinforced thermoplastic resin occur. In addition, there can be obtained a composite molded body that achieves rigidity and weight reduction efficiently while ensuring adhesiveness without causing warp deformation, and a method for producing the same.

It is a schematic side view which shows the lamination | stacking form of the composite molded object which concerns on this invention.

  The present invention uses a non-reinforced or discontinuous fiber reinforced thermoplastic resin as a core material, and is applied to at least one surface of the core material with respect to a thermoplastic resin (melting point: Tm (° C.)) used for the core material. Tm-140) A composite molded body in which a skin material made of continuous fiber reinforced thermoplastic resin is integrated through a thermosetting resin adhesive layer that undergoes a curing reaction at a temperature of not higher than Cm. As shown in FIG. 1, a core material 10 made of discontinuous reinforcing fibers 11 and a thermoplastic resin 12 and a skin material 20 are integrated with an adhesive 30.

  First, the thermoplastic resin used for the core material of the non-reinforced or discontinuous fiber reinforced thermoplastic resin constituting the composite molded body of the present invention will be described. In addition, the same resin can also be used for the thermoplastic resin used for the skin material of a continuous fiber reinforced thermoplastic resin. Preferably, when the thermoplastic resin of the core material and the skin material is the same type of resin, the bonding mode with the adhesive described later is equivalent, and generation of wrinkles and warpage can be suppressed.

  The thermoplastic resin of at least one of the core material and the skin material includes, for example, at least one of polyphenylene sulfide resin, polyamide resin, polyolefin resin, polyester resin, ABS resin, polycarbonate resin, polyacetal resin, and polyether ether ketone resin. It can be in the form. The thermoplastic resin used in the present invention is not particularly limited, and these resins may be used alone or as an alloy in which two or more kinds are mixed.

  The reinforcing fiber used in the composite molded body according to the present invention is not particularly limited. For example, as the reinforcing fiber of at least one of the core material and the skin material, carbon fiber, glass fiber, and aramid fiber are used. It can be set as the form containing at least 1 sort (s) chosen from. Among them, it is preferable to include carbon fiber in consideration of realization of high mechanical properties, ease of strength design, and the like.

  The number average fiber length of the discontinuous reinforcing fibers of the core material is preferably in the range of 0.01 to 20 mm. When the number average fiber length is less than 0.01 mm, it is difficult to obtain a reinforcing effect as a reinforcing fiber, and it becomes difficult to obtain desired rigidity and strength of the core material. On the other hand, if the number average fiber length exceeds 20 mm, random dispersion of discontinuous reinforcing fibers by injection molding may be difficult, and the uniformity as a composite molded body may be impaired.

  The reinforcing fiber of the skin material is not particularly limited, but the skin material is made of fiber reinforced thermoplastic resin, constitutes the surface layer of the structure in the final molded form, and bears the strength of the structure together with the core material, Since the rigidity of the structure is governed as a surface layer part, it is preferable to have high rigidity (bending rigidity or the like) in a desired direction. For that purpose, it is preferable that the reinforcing fiber of the skin material is composed of continuous fibers.

  As the skin material, a skin material in which reinforcing fibers are aligned in one direction and impregnated with a thermoplastic resin can be used. If such a skin material is used, even if it is a comparatively large large-area composite molded body, the skin material can be easily arranged at a predetermined position. Further, in this case, a form made of a plate-like skin material obtained by laminating or knitting a tape-like base material in which reinforcing fibers are aligned in one direction and impregnated with a thermoplastic resin can also be adopted as the skin material. If such a form is adopted, even if the structure is a relatively large large-area structure, the skin material can be easily arranged at a predetermined position, and desired mechanical properties can be easily imparted to the skin material.

  Moreover, the form containing a reinforced fiber fabric can be taken as a skin material. If such a form is employ | adopted, it will also become possible to give the desired designability to the surface of a composite molded object. In addition, by including the reinforced fiber fabric, it is possible to further improve the mechanical properties of the skin material itself that constitutes the surface layer of the composite molded body, so that the mechanical properties of the entire structure can be improved.

  The method for producing a skin material made of a continuous fiber reinforced thermoplastic resin aligned in one direction used in the present invention is not particularly limited.For example, continuous fibers are put into an impregnation die filled with a molten resin, The pultrusion method that pulls out from the slit die, the powder impregnation method in which a thermoplastic fiber powder is applied to a continuous fiber bundle and melt-pressed, the fiber that is a mixture of continuous reinforcing fiber and thermoplastic fiber is placed in a plate shape, and then hot pressed Can be mentioned.

  Moreover, the composite molded body which concerns on this invention can also arrange | position a skin material on both surfaces of a core material. If comprised in this way, it will be what is called a sandwich structure which sandwiched the core material of the low specific gravity expanded moderately by the two skin materials from both sides, and the lightweight property and high mechanical property of a structure are achieved more easily.

  In addition, an inorganic filler other than carbon fiber can be blended with the non-reinforced or discontinuous fiber reinforced thermoplastic resin which is the core material of the present invention. The inorganic filler used in the present invention is not particularly limited, such as a non-fibrous inorganic filler such as a plate, rod, or sphere, or a fibrous or acicular inorganic filler. Non-fibrous inorganic fillers include wollastonite, zeolite, sericite, kaolin, mica, clay, pyrophyllite, bentonite, asbestos, talc, alumina silicate and other silicates, alumina, silicon oxide, magnesium oxide, zirconium oxide, Metal compounds such as titanium oxide and iron oxide, carbonates such as calcium carbonate, magnesium carbonate and dolomite, sulfates such as calcium sulfate and barium sulfate, hydroxides such as magnesium hydroxide, calcium hydroxide and aluminum hydroxide, glass Examples thereof include fillers such as beads, ceramic beads, boron nitride, silicon carbide, and silica. These may be hollow, and two or more kinds of these fillers may be used in combination. Among these, particularly preferred fillers are talc and wollastonite. Examples of the fibrous or needle-like inorganic filler include glass fiber, potassium titanate whisker, zinc oxide whisker, fibrous calcium carbonate, and fibrous wollastonite. These fillers can be used in combination of two or more. It is.

  Although there is no restriction | limiting in particular in the addition amount of an inorganic filler, It is preferable to set it as 5 to 50 weight part with respect to 100 weight part of thermoplastic resins. In the case of 5 parts by weight or more, the effect of reducing the linear expansion coefficient is exhibited, which is preferable. Moreover, the fall of impact resistance can be suppressed by setting it as 50 weight part or less.

  In general, a synthetic adhesive is preferably used as the type of adhesive used in the adhesive layer. For example, acrylic resin, urethane resin, α-olefin, ether, ethylene-vinyl acetate resin, epoxy resin, vinyl chloride resin, chloroprene rubber, cyanoacrylate, silicone, styrene-butadiene rubber , Phenol resin system, polyamide resin system, polyimide system, polyolefin resin system, etc., but can be selected and changed according to the type of thermoplastic resin used in the composite molded product. Is higher than (Tm−140) ° C., the core material to be bonded and the skin material are distorted, and as a result, warp deformation, skin material wrinkles and the like are generated, which is not preferable. Accordingly, it is important in the present invention that the adhesive is cured in a temperature range of thermoplastic resin (Tm-140) ° C. or lower used for the molded composite.

  Moreover, it is preferable that the thickness of an adhesive bond layer is the range of 10-500 micrometers, More preferably, it is 50-200 micrometers. If it is 10 μm or less, the effect of the adhesive is not exhibited, and peeling easily occurs between the core material and the skin material. On the other hand, when the thickness is 500 μm or more, there is no problem with the adhesive force, but it is unsuitable from the viewpoint of labor during application and weight reduction.

  The method for applying and curing the adhesive can be appropriately changed according to the description of the recommended use conditions according to the type of the adhesive to be used, but the method for applying is not particularly limited. Moreover, about the hardening method of an adhesive agent, although use recommendation conditions are described by the adhesive agent to be used, the adhesive agent described as the curing temperature conditions below (Tm-140) degreeC of the thermoplastic resin used for a composite molded object Any adhesive can be used. When the curing temperature exceeds (Tm-140) ° C. of the thermoplastic resin used in the composite molded body, the stress relaxation due to heating of the thermoplastic resin and the difference in thermal shrinkage between the core material and the skin material when the temperature is lowered to room temperature again This is not preferable because warpage deformation due to the occurrence of warpage occurs. Therefore, the closer the curing temperature condition is to room temperature, the better.

  In addition, there is no problem with the surface of the adhesive applied to either the core material or the skin material, but when applied to both the core material and the skin material, the affinity and wettability between the core material and the skin material and the adhesive should be improved. This is the most preferable embodiment.

  Moreover, it is preferable to apply | coat both the core material and skin material which apply | coat the said adhesive agent in the state cooled to room temperature. In particular, when an adhesive is applied to the core material at a temperature immediately after injection molding, the core material may be warped during the cooling process, which is not preferable. Therefore, the temperature of the core material and the skin material to which the adhesive is applied is preferably closer to room temperature. In addition, in this invention, it is preferable that it is the range of 15-30 degreeC with room temperature, and 20-25 degreeC is more preferable.

  On the other hand, it is preferable to perform the curing reaction in an atmosphere of (Tm-200) ° C. or higher as the atmospheric temperature for the curing reaction. If it is less than (Tm-200) degreeC, since the hardening reaction of an adhesive bond layer will not advance easily and expression of adhesive strength will become difficult, it will not become a desirable mode.

  The present invention uses a non-reinforced or discontinuous fiber reinforced thermoplastic resin as a core material, and at least one surface of the core material is a thermosetting resin that undergoes a curing reaction at (Tm-140) ° C. or less with respect to the thermoplastic resin used for the core material. A composite molded body in which an adhesive layer made of resin is provided and a skin material made of continuous fiber reinforced thermoplastic resin is arranged thereon, and is particularly suitable for applications such as automotive interior and exterior parts that are excellent in rigidity and weight reduction. The present invention relates to a method for producing a composite molded body.

  Examples will be described in more detail below. In addition, although the characteristic of the composite molded object obtained by the present Example and the comparative example was measured and evaluated with the following method, this invention is not limited to these.

<Raw materials>
A discontinuous fiber reinforced thermoplastic resin and a skin material as the core material of the present invention were prepared as follows.

[Non-reinforced or discontinuous fiber reinforced thermoplastic resin (core material)]
(1) Nylon 6 resin: “Amilan” (registered trademark) CM1011G45 manufactured by Toray Industries, Inc.
(Melting point: 225 ° C., number average fiber length of glass fiber: 150 μm)
(2) Nylon 6 resin: “Amilan” (registered trademark) CM1011G30 manufactured by Toray Industries, Inc.
(Melting point: 225 ° C., number average fiber length of glass fiber: 150 μm)
(3) Nylon 6 resin: “Amilan” (registered trademark) CM1011G15 manufactured by Toray Industries, Inc.
(Melting point: 225 ° C., number average fiber length of glass fiber: 150 μm)
(4) Nylon 6 resin: “Amilan” (registered trademark) CM1017 manufactured by Toray Industries, Inc.
(Melting point: 225 ° C)

[Skin material]
Carbon fiber “Torayca” (registered trademark) T700S (12K) manufactured by Toray Industries, Inc. is lined up, put into an impregnation die filled with nylon 6 resin, and then drawn to form a 50 mm wide, 0.28 mm thick continuous fiber. A skin material A having a content of 50% by weight was obtained.

[adhesive]
Epoxy adhesive: “Araldite” (registered trademark) AW4859 / HW4859 (manufactured by Huntsman, Germany)
Acrylic adhesive: “Hard Rock” (registered trademark) NS-700M20A / NS-700M20B (manufactured by Denki Kagaku Kogyo Co., Ltd.)
Glass beads: φ100μm (used to adjust the adhesive layer thickness), 0.5 parts by weight mixed with 100 parts by weight of adhesive

[Method for evaluating composite molded body]
(1) Warp measurement In an evaluation test using strips cut out to 10 mm x 150 mm x 2.8 mm, one side of the strip length is fixed, and the height of the floating tip on the opposite side of the fixed surface using a gap gauge (Sledge) was measured. The measurement was performed at n = 3, and the comparison was performed using the average value.

(2) Bending evaluation A 10 mm × 150 mm × 2.8 mm strip test piece was cut out and the strip was pressed and bent at a span distance of 80 mm and a bending speed of 2 mm / min. The measurement was performed at n = 3, and the reinforcing effects by bending stress and bending elastic modulus were compared.

(3) Quality check of skin material A such as wrinkles, buckling, cracks, etc. Visually confirmed, those having no wrinkles, buckling, and peeling were evaluated with ○, and those with even one were determined with ×.

<Example 1>
As a discontinuous fiber reinforced thermoplastic resin, (1) CM1011G45 is injection-molded at a cylinder temperature of 280 ° C. and a mold temperature of 80 ° C., and a glass bead is applied to a core material A having a size of (100 × 150 × 2.5 mm). Was applied to one side of the core A at room temperature (25 ° C. = (Tm−200) ° C.). Next, the same acrylic adhesive was applied to the skin material A (100 × 150 × 0.3 mm), and then both were pasted, and the surface pressure was 160 g / cm ² in a form controlled to an adhesive thickness of 0.1 mm. In this state, the composite molded body A (100 × 150 × 2.9 mm) was obtained after curing for 24 hours at room temperature (25 ° C. = (Tm−200) ° C.).

<Example 2>
It apply | coats similarly to Example 1 except having used the epoxy-type adhesive agent with respect to the core material A of Example 1, and both are affixed and 80 degreeC (= Tm) in the state used as a surface pressure of 160 g / cm < ² >. -145) After curing at 3 ° C for 3 hours, a composite molded body B was obtained.

<Example 3>
A composite molded body C was obtained in the same manner as in Example 1, except that (2) the core material B using CM1011G30 was used as the discontinuous fiber reinforced thermoplastic resin.

<Example 4>
A composite molded body D was obtained in the same manner as in Example 3 except that the epoxy adhesive described in Example 2 was used as the adhesive.

<Example 5>
A composite molded body E was obtained in the same manner as in Example 1, except that (3) the core material C using CM1011G15 was used as the discontinuous fiber reinforced thermoplastic resin.

<Example 6>
A composite molded body F was obtained in the same manner as in claim 5 except that the epoxy adhesive described in Example 2 was used as the adhesive.

<Example 7>
A composite molded body G was obtained in the same manner as in Example 1 except that (4) the core material D using CM1017 was used as the non-reinforced thermoplastic resin.

<Example 8>
A composite molded body H was obtained in the same manner as in Example 2, except that the epoxy adhesive described in Example 2 was used as the adhesive.

<Comparative Example 1>
The skin material A (100 × 150 × 0.3 mm) is set on one side of the cavity surface of the mold, and (1) CM1011G45 is used as the discontinuous fiber reinforced thermoplastic resin, the cylinder temperature is 280 ° C., the mold temperature is 80 ° C. The composite molded body I (100 × 150 × 2.8 mm) with the core material A was obtained.

<Comparative Example 2>
A composite molded body J with the core material B was obtained in the same manner as in Comparative Example 1 except that (2) CM1011G30 was used as the discontinuous fiber reinforced thermoplastic resin.

<Comparative Example 3>
A composite molded body K with the core material C was obtained in the same manner as in Comparative Example 1 except that (3) CM1011G15 was used as the discontinuous fiber reinforced thermoplastic resin.

<Comparative example 4>
A composite molded body L with the core material D was obtained in the same manner as in Comparative Example 1 except that (4) CM1017 was used as the non-reinforced thermoplastic resin.

  Table 2 shows the physical property evaluation results of the composite molded articles obtained with the compositions shown in Table 1. In all of Examples 1 to 8, the adhesion of the skin material A is good, and the effect of improving the bending stress and the elastic modulus in bending evaluation is great. I did not check it on my body either, and found that there was no problem.

  On the other hand, in all of Comparative Examples 1 to 4, warp deformation is caused by the difference in thermal shrinkage between the core material and the skin material. Compared with Comparative Example 1, Comparative Examples 2 to 4 and the amount of discontinuous fibers are reduced. It turns out that the deformation becomes very large. The effect of improving bending stress and elastic modulus in bending evaluation can be confirmed, but as a result of visual confirmation of the skin material A in each composite molded product, wrinkles occur in part of the skin material due to the difference in thermal shrinkage between the core material and the skin material. And it was found that some peeling occurred. In addition, it was found that the number of wrinkles generated in Comparative Examples 3 and 4 with large warp deformation was very large, and the skin material A was buckled and peeled off.

  The present invention uses a non-reinforced or discontinuous fiber reinforced thermoplastic resin as a core material, and at least one surface of the core material is a thermosetting resin that undergoes a curing reaction at (Tm-140) ° C. or less with respect to the thermoplastic resin used for the core material. With regard to a composite molded body in which a resin adhesive layer is provided and a skin material made of continuous fiber reinforced thermoplastic resin is disposed thereon, and a method for producing the same, it is particularly suitable for applications such as automobile interior and exterior parts having excellent rigidity and weight reduction. Used for.

DESCRIPTION OF SYMBOLS 10 Core material 11 Discontinuous reinforcement fiber 12 Thermoplastic resin 20 Skin material 30 Adhesive

Claims (6)

(Tm-140) with respect to the thermoplastic resin (melting point: Tm (° C.)) used for the core material, which is applied to at least one surface of the core material, using a non-reinforced or discontinuous fiber reinforced thermoplastic resin as a core material. A composite molded body, which is integrated with a skin material made of a continuous fiber-reinforced thermoplastic resin via a thermosetting resin adhesive layer that undergoes a curing reaction at a temperature of not higher than ° C. The composite molded article according to claim 1, wherein the number average fiber length of the discontinuous reinforcing fibers contained in the core material is 0.01 to 20 mm. 3. The composite molded body according to claim 1, wherein the skin material is one in which reinforcing fibers are aligned in one direction and impregnated with a thermoplastic resin. 4. The said skin material consists of a plate-shaped skin material which laminated | stacked or knitted the tape-shaped base material which aligned the reinforcement fiber in one direction and was impregnated with the thermoplastic resin, The any one of Claims 1-3 characterized by the above-mentioned. A composite molded article according to any one of the above. When the skin material is laminated on the core material via the adhesive layer, the thermoplastic resin (melting point: Tm (° C.)) used for the core material and the skin material is (Tm−200) ° C. or higher. The composite molded body according to any one of claims 1 to 4, wherein a curing reaction is performed in an atmosphere. Composite molding in which a non-reinforced or discontinuous fiber reinforced thermoplastic resin is injection molded into a flat core material, and a skin material made of continuous fiber reinforced thermoplastic resin is laminated on at least one surface of the core material through an adhesive layer. In the body manufacturing method, the adhesive layer is applied in a state where the surface temperature of the core material and the skin material is cooled to room temperature, and the thermoplastic resin (melting point: Tm (° C.) used for the core material and the skin material is used. )), A curing reaction at a temperature of (Tm-140) ° C. or lower, and then cooling to room temperature.

Images