JPH03161321A - Manufacture of laminated pipe - Google Patents

Abstract

PURPOSE:To obtain a laminated pipe whose tenacity and shock absorbing properties are high, by a method wherein a film layer which is comprised of an organic polymer whose melting point is at least 300 deg.C and possess specific tensile strength and the tensile modulus of elasticity and a fiber-reinforced thermosetting resin layer are wound round with specific tension. CONSTITUTION:A film layer is constituted substantially of an organic polymer whose melting point or decomposition point is at least 300 deg.C and possesses tensile strength of at least 35kg/mm<2> and the tensile modulus of elasticity of at least 700kg/mm<2> and a fiber-reinforced thermosetting resin layer are wound round while giving tension of at least 8kg/mm<2>, laminated, unified and a laminated pipe is formed. Aramid, polyimide and whole aromatic polyester are available as an exemplification of the organic polymer whose melting point or decomposition point is at least 300 deg.C. The fiber-reinforced thermosetting resin layer is of a prepreg material obtained by infiltrating the thermosetting resin into a reinforcement fiber. In addition, it is preferable that the foregoing film thickness is in the extent of 10-50 mum.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a laminated tube in which a high-strength, high-modulus film layer and a fiber-reinforced thermosetting resin layer are laminated and cured together, and further relates to More specifically, the present invention relates to a method for manufacturing a tubular molded product that has both improved and extremely high impact absorption properties and excellent mechanical properties.

[Conventional technology and its problems]

A tubular molded product made from a thermosetting resin reinforced with carbon fiber or glass fiber takes advantage of its advantages such as light weight, high strength, and high corrosion resistance, and has been used in applications such as spinning bobbins, various industrial piping, and, in recent years, fishing rods. It is used in a wide range of fields, including sports equipment such as golf club shafts and rocket cases.

In recent years, research and development on tubular molded bodies made of highly versatile composite materials has been carried out everywhere.
Also, many new technologies have been disclosed.

However, most of the new technologies are generally aimed at improving and balancing various mechanical properties, or applied processing such as plating, lining processing, and joining with metal, and are aimed at improving and balancing various mechanical properties, or applying processing such as plating, lining processing, and joining with metal. There are few attempts to improve the poor impact resistance, which is considered to be a drawback. There is an example of an attempt to improve shock absorption by using a combination of carbon fiber and aramid fiber as reinforcing materials, and it was effective, but when aramid fiber was used, it was difficult to cut, so it was difficult to process. The machinability is extremely poor, such as the surface becoming loose and fluffy, which is a big problem in practice.

On the other hand, if only improving toughness or shock absorption is considered, it is possible to introduce rubber, elastomer, or thermoplastic resin into the rod; It is clear that this will involve sacrificing the

[Problem to be solved by the invention]

The present invention has been made in view of the above points, and is a fiber reinforced resin laminated pipe that has extremely high toughness and shock absorption properties and is easy to machine, without impairing the excellent mechanical properties inherent in the fiber reinforced resin laminated pipe. An object of the present invention is to provide a method for manufacturing a reinforced resin laminated tube.

[・Means to solve the problem]

As a result of repeated research to solve the above problems, we found that a recently developed film with extremely high tensile strength and tensile modulus is laminated onto a fiber-reinforced thermosetting resin layer and then cured and integrated to produce a laminated tube. toughness without compromising mechanical properties,
It was found that the shock absorption properties were improved. As a result of further investigation based on this knowledge, it was found that when laminating a film on a fiber-reinforced thermosetting resin layer, the film was laminated under a tension of 8 kg/mm or more and then cured and integrated to produce a laminated tube. The present invention was completed based on the new fact that the gripping effect of the film layer not only significantly improves toughness and shock absorption, but also improves mechanical properties.

That is, the present invention provides a film layer consisting essentially of an organic polymer having a melting point or decomposition point of 300° C. or higher and having a tensile strength of 35 kg/11 m or higher and a tensile modulus of 700 kg/mm or higher, and a fiber-reinforced thermal film layer. A method for producing a laminated tube in which a curable resin layer is wound, laminated, and integrated, the laminated tube being wound while applying a tension of 8 kg/mm' or more when winding the film. This is the manufacturing method.

The film used in the present invention must meet the requirements described below.

First, films and tapes must be substantially composed of organic polymers that do not have a melting point below 300°C. If the melting point is less than 300°C, it is undesirable because it will melt or be thermally deformed during the composite manufacturing process such as curing the resin, and even after it is commercialized, the performance may deteriorate if the usage environment is a little harsh. This is not preferable as it may cause a significant decrease. Examples of such high melting point organic polymers include aramid, polyimide, polyetheretherketone, wholly aromatic polyester, polybenzimidazole, polybenzbisthiazole, etc. high strength,
Aramid and polyimide because of their ease of developing high elastic modulus, etc.
Among them, aramid is preferred.

Preferably used aramids have the following general formula (1),
(II) or copolymers thereof.

(In the formula, Rl+ R, and R are selected from, and these hydrogen atoms may be substituted with functional groups such as halogen, methyl, ethyl, methoxy, nitro, and sulfone. m and n are average polymerization degree and about 50~l
It is 000. ) The film used in the present invention essentially consists of a specific organic polymer, which means that components other than the above-mentioned specific organic polymer may be contained in small amounts within the range that does not impair the effects of the present invention. For example, a small amount of an organic polymer, an organic low molecular compound, an inorganic compound, etc. other than those mentioned above may be contained.

Next, the film used in the present invention must have a tensile strength of 35 kg/mm2 or more and a tensile modulus of 700 kg/mm2 or more.This film has outstanding physical properties compared to conventional general-purpose films. It is clear that the mechanical properties of the fiber-reinforced resin layer are low, and these requirements must be met in order to prevent the mechanical properties of the final molded product from deteriorating as much as possible. , preferably has a tensile strength of 45 kg/mm' or more, or has a tensile modulus of IOOO kg/mm2 or more.The film has the necessary tensile strength as a composite product. Although a so-called tensilized type film with enhanced tensile strength and tensile modulus in the direction may be used, it is of course better to use a film with isotropic performance because the mechanical properties of the resulting molded product are improved. In the present invention, the tensile strength and tensile modulus are at least 1.
It is sufficient that one direction satisfies the above-mentioned value, but preferably, the average value of the characteristics in two arbitrarily selected directions orthogonal to each other satisfies the above-mentioned value.

In the present invention, in order to sufficiently exhibit the reinforcing effect, it is preferable that the film and the thermosetting resin have sufficient adhesive strength. Great adhesion can be achieved by making the surface of the film or tape rougher through film formation, physical or chemical etching after film formation, and chemical activation of the surface through corona discharge treatment, plasma treatment, or chemical decomposition. Methods such as introducing a seed, pre-impregnation treatment for adhesion with an epoxy compound, isocyanate compound, resorcinol/formalin/latex mixture, etc., or a combination of these methods are preferably used and achieved by these methods.

The thickness of the film used in the present invention is determined by considering the laminated structure of the film layer and fiber-reinforced resin layer in the molded product. Although it is determined appropriately, it is usually 5 to IO llm, preferably 10 to 50 μm.

The fiber-reinforced thermosetting resin layer in the present invention refers to a prepreg material obtained by impregnating reinforcing fibers with a thermosetting resin.

Examples of reinforcing fibers used in the present invention include glass fibers, carbon fibers, aramid fibers, polybenzimidazole fibers,
It also includes polybenzothiazole fibers, metal-coated fibers such as nickel-plated carbon fibers, and inorganic fibers such as alumina fibers and silicon carbide fibers, and two or more of these fibers may be used in combination. can.

In addition, fibers are used in the form of sheets aligned in one direction or in the form of woven fabrics, and in applications where isotropic mechanical properties are particularly required, fibers cut into appropriate lengths or continuous fibers are used. It is also used in the form of a mat with randomly oriented fibers.

The thermosetting resin used in the present invention is not particularly limited, and is selected from, for example, epoxy resins, phenol resins, polyimide resins, polyester resins, and the like. In addition, these resins include ultraviolet absorbers, flame retardants, antioxidants, lubricants, colorants, heat stabilizers, anti-aging agents, reinforcing short fibers, reinforcing powders, disciplinary agents, and thermoplastic resins. , elastomers, rubbery materials and other conventional resin additives may be added.

The laminated structure of the film layer and the fiber-reinforced thermosetting resin layer is such that the fiber-reinforced thermosetting resin layer and the film layer are alternately laminated, or the film layer is laminated on the outside of the fiber-reinforced thermosetting resin layer. Those with a film layer laminated on the inside of a fiber-reinforced thermosetting resin layer, those with a so-called sandwich structure in which film layers are laminated on both sides of a fiber-reinforced thermosetting resin layer, and those with the opposite structure. However, from the viewpoint of shock absorption and destruction protection, a structure in which a film layer is arranged as the outermost layer is preferable to a structure in which fiber-reinforced thermosetting resin layers and film layers are alternately laminated. More preferably, the outermost layer and the innermost layer are filled! The one with Rem placed is good. The lamination ratio can be appropriately selected depending on the mechanical properties desired for a certain shape, but in general, the ratio of the film to the entire laminated tube is preferably in the range of 5 to 50%, more preferably 10 to 20%.

If both sides of the film are in contact with the fiber-reinforced thermosetting resin layer, the films to be laminated may be laminated as is, or if multiple layers of film are to be laminated in succession, at least one layer of the film may be laminated in advance. A thermosetting resin is coated on one side using a coater or the like, and heated if necessary to form a so-called B stage.

Further, the form of the film used may be a general wide film, but a relatively narrow tape-like film can also be used in the same manner as the filament winding method.

Furthermore, it is possible to use one continuous film, or to use a plurality of films laminated in advance.

In the present invention, when winding and laminating the above film, it is necessary to wind the film while applying a tension of 8 kg/mm 2 or more to the film. 8 kg/+nm
When winding is carried out under a tension of 2 or less, the adhesion between the laminated layers is poor and delamination is likely to occur, resulting in a molded article with insufficient physical properties. Further, the film layer tends to wrinkle, and these wrinkles cause deterioration of physical properties, which is also unfavorable in terms of appearance. It is preferably 10 kg/mm2 or more, more preferably 12 kg/mm'' or more.The upper limit may be taken into consideration depending on the strength of the film.

Even if multiple sheets are laminated in advance, in order to improve the adhesion between each laminated layer, the lamination weight is 8 kg /
This should be done under a tension of at least 2 mm.

Furthermore, it goes without saying that when laminating a plurality of film layers laminated together with a fiber-reinforced thermosetting resin layer, it is necessary to do so with a tension of 8 kg/mm 2 or more.

A laminated pipe with significantly improved toughness and shock absorption properties without impairing the high mechanical properties originally possessed by fiber-reinforced thermosetting resin pipes can be produced, for example, by the following method. After winding the fiber-reinforced thermosetting resin layer around the mold, the thermosetting resin is coated in advance and heated to form the B stage, and the film is supplied from a creel machine, etc., and the tension of the film is 8 kg/I.
After winding the fiber-reinforced thermosetting resin layer with a creel machine while applying the brakes so that the thickness is at least 2 nm, the entire mold is placed in a heating oven and cured to form an improved laminated layer. Pipes can be manufactured.

In addition, the B-staged film layer is supplied in the form of a narrow tape, and for example, a general-purpose taping machine or the like is used to
It can be manufactured by winding it onto a fiber-reinforced thermosetting resin layer that has already been wound with a tension of kg/mm2 or more.

Generally, when manufacturing a laminated tube by winding and laminating fiber-reinforced thermosetting resin prepreg, curing is performed by taping release tape as a substitute for the outer mold in order to consolidate the rod-shaped body and prevent resin from flowing out. However, in the present invention, when a film layer is laminated as the outermost layer, this operation can be omitted and the molding process can be simplified.

〔Example〕

Hereinafter, this manufacturing method will be explained in more detail with reference to Examples.

The physical properties of the laminated tube were measured under the following conditions.

Four-point bending fracture strength: distance between indenters 150 mm, distance between fulcrums 500 mm (both indenter and fulcrum R = 501 Im), bending speed 30 + nm/min, sample length 650 n + m0-axis compression: compression speed l + nm/min, sample length 13 mm / surface Compression: compression speed 1+nm/min, sample length 17 mm.

Izod impact: Weighing 150 kg-Cm (hammer weight 874 kg), swinging angle 135 degrees, sample length 64 mm The state of adhesion between the inner layer and the outer layer of Film B was observed and evaluated based on the presence or absence of voids.The surface appearance was evaluated visually for wrinkles.

First, for film production, polyp-phenylene terephthalamide (abbreviated as PPTA) was dissolved in 98% concentrated sulfuric acid and had a logarithmic viscosity of 5.5 measured at 30°C at C=0.5g/100-. ) was dissolved in 99.5% sulfuric acid at a polymer concentration of 12% to obtain a dope with optical anisotropy.

This dope is degassed under vacuum and filtered, then extruded through a slit die through a gear pump, cast onto a mirror-polished tantalum belt, and passed through a zone of air atmosphere at approximately 90°C with a relative humidity of approximately 40%. The cast dope was made optically isotropic and introduced together with the belt into a 30% aqueous sulfuric acid solution at 20° C. to solidify. The coagulated film was then peeled off from the belt, neutralized with an aqueous solution of caustic soda, and washed with water. Without drying the washed film, it was stretched approximately 115 times in the length direction with a roller, then 1.3 times in the width direction with a tenter, and then stretched for 20 minutes while keeping the film at a constant length.
It was dried at 0°C and further subjected to fixed length treatment at 300°C to produce a 20 μm PP'FA film.

The resulting film was pale yellow and transparent, with a thermal analysis of 50
No transition temperature was observed below 0°C.

In addition, the tensile strength and elastic modulus are 48k each in the length direction.
g/mm2, 1490kg/mm'', widthwise 47 kg/mm2, 1420kg/mm, respectively
mm' (referred to as film A).

The thermosetting resin-coated film is made by using an epoxy resin (trade name #77.14 methyl ethyl ketone mixture, solid content 70% by weight) manufactured by Chemical Fiberlite ((1)) on one side of the above P P TA film. Coated using a comma direct method using a roll machine (Kawasha Coating Machine, 100%
A thermosetting resin coated film (referred to as film B) was produced by heating at ℃ for 15 minutes. The thickness of this film B is approximately 30
It was μm.

In addition, the fiber-reinforced thermosetting resin was prepared by impregnating 12,000 acrylonitrile carbon fibers with a fiber diameter of 12 μm aligned in one direction with Asahi Nippon Carbon Fiber (manufactured by Kikusha Co., Ltd.) with epoxy resin manufactured by Kaoru Fiberlite (Kikusha Co., Ltd.). While doing so,
This was wrapped with silicone release paper to a diameter of 500 mm.
wound onto a drum. This was cut in a direction perpendicular to the fiber direction and heated at 100° C. for 30 minutes to produce a unidirectional fiber-reinforced thermosetting resin (referred to as CF prepreg). The thickness of this CF prepreg is approximately 0. 2 Illm.

Example 1 A CF prepreg with a length in the fiber direction of 400fflrTl was placed in a stainless steel round bar mold with a diameter lowφ and a length of 500 mm using a roller rolling machine manufactured by Shinano Kogyo (Kiki). Five layers were wound and laminated so that the length directions of the molds matched.

The round bar mold wound with this CF prepreg was attached to a Shimano Kogyo (immediately made taping machine).
The tape-shaped film B, which was slit into a length of m and wound around a paper tube, was set in the paper tube mounting section of a taping machine. After passing this film B through a predetermined guide roll, it was attached to the left end of the wound CF prepreg with the resin coating surface facing the CF prepreg side. After that, the taping machine is driven and the round bar mold is rotated at 20 revolutions/minute to pitch 2. 5 mm and a tension of 8 kg/+n+n2. The obtained laminate was further wrapped with a 25 μm thick polyethylene terephthalate tape (hereinafter referred to as PET tape) that had been subjected to a release treatment.

The wrapping conditions at this time were the same as those for film B tape winding.

The round bar mold around which this laminate was wound was removed from the taping machine and cured for 2 hours in a hot air circulation type heating device at 140°C. The PET tape was removed from the cured molded body, and the round bar mold was extracted using a de-coring machine and had an inner diameter of 10 mmφ and a wall thickness of 1.
A laminated tube having a length of 400 mm and consisting of a CF layer as an inner layer and a PPTA film layer as an outer layer was obtained.

Example 2 The same round bar mold as used in Example 1 was mounted on a taping machine, and then tape-shaped film B having a width of 15 mm was laminated on the round bar mold in the same manner and under the same conditions as in Example 1. At this time, the total length of the film layer was 400 wun.

The mold with this film layer wound thereon was removed from the taping machine, and then CF prepreg was wound and laminated using the same roller rolling machine as in Example 1 under the same method and conditions. This round bar mold was mounted on the taping machine again, and tape-shaped film B having a width of 15 mm was wound on the CF pre-reg under the same conditions as those used for winding the innermost layer. Then, the PET tape was wrapped, heated, hardened, shaped, and decoreated in the same manner and under the same conditions as in Example 1 to obtain a laminated tube with a so-called sandwich structure in which the innermost and outermost layers were film layers and the middle layer was a CF layer. Ta.

Example 3 The same round bar mold used in Example 1 was installed in a taping machine. Next, tape-shaped film B, which had been slit to a width of 10 mm and wound around a paper tube, was set in the paper tube mounting section of the taping machine. This film B was passed through a predetermined roller and then attached to the left end of a round bar mold.

At this time, the resin-coated side of Film B was attached to the mold side. Drive the taping machine and make two round bar molds.
Rotate at 0 rotations/min, pitch 10mm, tension 10kg/
Winding was performed in mm2. The width of the winding was 400 mm. This round bar mold was removed from the taping machine and one layer of CF prepreg with a length of 400 mm in the fiber direction was wound on top of the film layer, which was wound so that the fiber direction and the length direction of the round bar mold matched. It was rolled and laminated.

Again, attach the round bar mold to the taping machine and tape-shaped film B with a pitch of 10 mm and a tension of 10 kg/mm.
' was wound on top of CF prepreg. Next, the length is 400+
One layer of nanometer CF prepreg was wound on the film layer.

This method was repeated to obtain a laminate in which film B and CF prepreg were alternately overlapped. The number of films B in this laminate was six, and the number of CF prepregs was five. The round bar mold in which this laminate was wound was set in a taping machine, and PET tape wrapping, heat curing or shaping, and decore were performed in the same manner and under the same conditions as in Example 1 to produce a laminate tube in which CF and film were alternately laminated. I got it.

Example 4 A stainless steel round bar mold with a diameter of 10IIITlφ and a length of 200 m was used, and the length in the fiber direction was 100 m.
Using a roller rolling machine, 5 layers of CF prepreg were wound and laminated so that the fiber direction and the length direction of the round bar mold matched. The round bar mold in which this CF prepreg was wound and laminated was installed in a taping machine manufactured by Shimano Industries. Film B, which had been slit to a width of 100 mm and wound around a paper tube, was set in a paper tube mounting section with a brake mechanism. After passing this film B through a predetermined roll, it was bonded to the wound CF prepreg.At this time, the resin coated side of film B was bonded to the CF prepreg side. The side edges of the prepared CF prepreg layer and the side edges of Film B were bonded together so that they matched.

After that, the taping machine was driven to rotate the round bar mold at 20 revolutions/minute, and the film B was stretched at a tension of 8 kg/mm.
2, it was wound six times and laminated. Thereafter, hardening, shaping, and core removal were performed in the same manner and under the same conditions as described in Example 1 to obtain a laminated tube.

Comparative Example 1 Using the same mold and equipment as used in Example 1,
Six layers of 00 mm CF prepreg were wound and laminated so that the fiber direction and the length direction of the round bar mold matched. The round bar mold in which this CF prepreg was wound and laminated was mounted on a taping machine manufactured by Shimano Industries ■.

Next, the PET tape was wrapped, cured, and decoreated in the same manner and under the same conditions as in Example 1 to obtain a laminated tube with an inner diameter of 10+ nm, a wall thickness of III m, and a length of 400 mm, consisting only of a CF layer.

Comparative Example 2 The tension when winding tape-shaped film B was 5 kg.
/ mm'', but the same method as in Example 1,
Inner diameter 10mm, wall thickness ffflm, length 400mm
A laminated tube was obtained.

Comparative Example 3 The tension when winding sheet-like film B was 5 kg.
/ Inm'', the same method and conditions as in Example 2 were used, with an inner diameter of 10 mm, a wall thickness of lIIIm, and a length of 100+.
A laminated tube of nm size was obtained.

Table 1 shows the mechanical properties of the laminated tubes of Examples 1 to 4 and Comparative Examples 1 to 3.

The laminated tubes obtained in this example could all be cut with a round-blade cutter, and could be easily processed using a lathe, polished with sandpaper, drilled, and threaded. Further, no fuzzing or other abnormal defects were observed on each processed surface.

Margin [Effects of the Invention] By using the production method of the present invention, a high-performance organic film and a fiber-reinforced thermosetting resin are integrated to a high degree, which is impossible to obtain with conventional fiber-reinforced resin bodies. It is now possible to manufacture laminated pipes with high strength and high modulus of elasticity that also have a high degree of impact resistance, which was previously not possible.

In addition, the laminated tube obtained by the manufacturing method of the present invention has the biggest drawback of the laminated tube obtained by using aramid fiber in combination.
Since there is no peeling or lint on the machined surface during machining, machining such as cutting with a round blade cutter, drilling with a drill press, grinding with a lathe, and thread cutting can now be performed very easily. .

The laminated tube obtained by the manufacturing method of the present invention can be used for various tubular products such as golf club shafts, fishing rods, ski poles, bicycle frames, and scuba cylinders by taking advantage of these excellent properties. I can do it.

Claims (1)

[Claims] 1. A film layer consisting essentially of an organic polymer with a melting point or decomposition point of 300° C. or higher and having a tensile strength of 35 kg/mm^2 or higher and a tensile modulus of 700 kg/mm^2 or higher, and a fiber-reinforced thermal film layer. A method for manufacturing a laminated tube in which a curable resin layer is wound, laminated, and integrated, characterized in that the film is wound while applying a tension of 8 kg/mm^2 or more. manufacturing method.