JPH0757809B2 - Fiber reinforced plastic and method for producing the same - 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 plastic and a method for producing the same, and more particularly to armor such as helmets, automobile parts such as bumpers, or vibration preventing materials, which are required to have vibration damping characteristics and impact resistance. The present invention relates to a fiber-reinforced plastic which is preferably used as an electromagnetic wave shield material and the like and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, this type of fiber reinforced plastic
As a method for producing (FRP), in the state where the fiber reinforcement is placed in the mold, the unreacted raw material liquid of the matrix resin composed of nylon, cyclopentadiene, epoxy, urethane, etc. is injected, and the reinforcing fiber is formed in the mold. There is provided a reaction injection molding method or a resin transfer molding method in which a material is impregnated with the above raw material liquid to cause a reaction to solidify.

Other than the above-mentioned reaction injection molding method or resin transfer molding method, there are the following methods (a) to (c) for manufacturing FRP molded products. (a) A method in which a thermoplastic resin reinforced by mixing short fiber reinforcement is injected into a mold to obtain a molded product; (b) a prepreg in which continuous fibers are impregnated with a thermosetting resin is heated and pressed to be molded. (C) A method in which a fiber reinforced material and a thermoplastic resin composed of a matrix resin are mixed and woven, and heated and pressed to obtain a molded article.

[0004]

Although there are no problems in the production methods listed in the above (a) to (c), when the production method of the FRP molded article by the reaction injection molding method or the resin transfer molding method is used, There is a problem that polymerization failure is likely to occur during the reaction. That is, in the other manufacturing method described above, when the thermoplastic resin of (a) and (c) is used, the molding of the resin has already been completed, so that a polymerization failure that occurs during the reaction that is a problem in the method of the present invention Does not pose a problem, and there is no concern that the reinforcing fiber material will cause curing failure of the resin even when the thermosetting resin of (b) is used.

On the other hand, in the case of producing an FRP molded article by the reaction injection molding method or the resin transfer molding method, when the reaction is caused while impregnating the unreacted raw material liquid in the fiber reinforcement in the mold, Polymerization-inhibiting compounds listed in the above, or fiber or sizing agent,
When the surface treatment agent or the like contains the above-mentioned polymerization inhibitor compound,
There is a problem that these polymerization-inhibiting compounds deprive the activity of the catalyst and cause poor polymerization.

The above-mentioned polymerization-inhibiting compounds that deprive the catalyst of activity tend to occur when organic fibers such as aramid, polyarylate and vinylon are used when the matrix resin is nylon, and a fiber sizing agent. It also occurs when polyester is used.

More specifically, in the case of subjecting nylon to reaction injection molding, the following compounds (1) to (4) are listed as compounds that inhibit the polymerization thereof. Compounds having the following active hydrogen-Compounds having a hydroxyl group such as water and alcohol-Compounds having an amino group-Compounds containing a carboxyl group (an acid anhydride group) Halogen compounds, particularly aliphatic-added halogen compounds. Compounds with poor alkali resistance, such as polyester,
Polycarbonate, polyurethane, etc. (These compounds generate active hydrogen by decomposition, etc.)

Further, when the fiber or the sizing agent has a low thermal conductivity, the polymerization rate may be lowered due to insufficient heat quantity, which may cause a polymerization failure.

Further, even if satisfactory polymerization is obtained, in order to bring out the characteristics of the composite material of the fiber reinforcing material and the matrix resin, it is necessary to sufficiently bond the interface between the fiber and the matrix resin. However, in the case of the conventional reaction injection molding method or resin transfer molding method, there is a problem in that the adhesion is not sufficient.

The present invention has the problems which occur when a fiber reinforced plastic product is manufactured by the above-mentioned reaction injection molding method or resin transfer molding method.
It is an object of the present invention to solve the problem of poor polymerization and lack of adhesive strength, and in particular to enable the use of a fiber reinforcing material which could not be used conventionally due to poor polymerization.

[0011]

In order to achieve the above object, the present invention is characterized in that the surface of the fiber reinforcing material is coated with a metal. That is, the present invention provides a fiber reinforced plastic comprising a fiber reinforced material whose surface is coated with a metal, and a matrix resin obtained by reaction injection molding or resin transfer molding.

Further, according to the present invention, after arranging a fiber reinforced material whose surface is coated with a metal in advance in a mold, an unreacted raw material liquid is injected into the mold, and the fiber reinforced material is added in the mold. The present invention provides a method for producing a fiber-reinforced plastic, which is characterized by molding by a reaction injection molding method or a resin transfer molding method in which a reaction occurs while impregnating.

Furthermore, in the present invention, a fiber reinforcing material which is adjusted to have a length of several millimeters or several microns and which is previously coated with metal is filled in the monomer, and the monomer containing the fiber reinforcing material is filled with gold. It is intended to provide a method for producing a fiber-reinforced plastic, which is characterized by injecting it into a mold and molding by a reaction injection molding method or a resin transfer molding method.

As a method for coating the above-mentioned fiber reinforcing material with a metal, a known method such as a vapor deposition method, a sputtering method or a plating method can be used. The metal to be coated is N
i, Fe, SUS, Mn, Sn, Al, Cu, Ti and the like are used.

As the reinforcing fiber material, inorganic fibers or organic fibers are used depending on the application. Specifically, carbon fiber, glass fiber, alumina fiber, silicon carbide fiber,
Steel wires, amorphous metal fibers, aramid fibers, polyester fibers, nylon fibers, polyethylene fibers and / or mixtures thereof are preferably used.

The above-mentioned reinforcing fiber material is preferably continuous fiber or continuous fiber in view of its mechanical properties, but the fiber length is not limited. Further, the form of the fiber and the content rate of the fiber can be appropriately changed according to the application and are not limited.

Examples of the matrix resin used in the above reaction injection molding method or resin transfer molding method include nylon, cyclopentadiene, epoxy, urethane and the like.

When the matrix resin molded by the above reaction injection molding or resin transfer molding method is nylon, that is, in RIM nylon, molten lactams containing a polymerization catalyst and a polymerization initiator are injected into a mold, It is molded by a monomer casting method in which it is subjected to polyamide polymerization by heating.

The ω-lactams which are the above-mentioned monomers include α-pyrrolidone, α-piperidone, ω-enanthlactam, ε-caprolactam, ω-caprylactam,
ω-pelargonolactam, ω-decanolactam, ω-undecanolactam, ω-laurolactam, c-alkyl-substituted-ω-lactams thereof, and mixtures of two or more kinds of these ω-lactams. Also,
The ω-lactam can optionally contain an improving component (soft component). The soft component is a compound having a functional group that reacts with the initiator used in the molecule and has a low Tg, and a polyether having a normal functional group, liquid polybutadiene, or the like is used.

Commercially available raw materials used as the above-mentioned ω-lactams are UBE nylon (U manufactured by Ube Industries, Ltd.).
X-21) etc. It is composed of an A component consisting of an alkali catalyst and caprolactam, a prepolymer containing a soft component and a B component consisting of caprolactam.

As the above-mentioned polymerization catalyst, sodium hydride is preferred, but other known ω-lactam polymerization catalysts such as sodium, potassium and lithium hydride can be used. The amount added is 0 for ω-lactam.
The range of 1-0.5 mol% is preferable.

As the polymerization initiator (activator), N
-Acetyl-ε-caprolactam is used, but other triallyl isocyanurates, N-substituted ethyleneimine derivatives, 1.1'-carbonylbisaziridine, oxazoline derivatives, 2- (N-phenylbenzimidoyl) acetanilide, 2 Compounds such as-(N-phenylbenzimidoyl) acetanilide, 2-N-morpholino-cyclohexene-1.3-dicarboxanilide, and known isocyanates and carbodiimides can be used. The amount of the polymerization initiator added is preferably within the range of 0.05 to 1.0 mol% with respect to the amount of ω-lactam.

When a cyclopentadiene resin is used as the matrix resin, dicyclopentadiene can be used as the polymerizable monomer for the cyclopentadiene resin.
Dihydrodicyclopentadiene, tricyclopentadiene, tetracyclopentadiene, cyclopentadiene-
A methylcyclopentadiene co-duplex or the like is used.

As the polymerization catalyst for the cyclopentadiene resin, halides such as tungsten, molybdenum and tantalum, oxyhalides, oxides and organic ammonium salts are preferably used. As the polymerization initiator, organometallic compounds centered on alkylated metals of metals of groups I to III of the periodic table, oxygen-containing compounds such as alcohols and phenols are preferably used.

Furthermore, since the polymerization reaction of the solution containing the above-mentioned polymerization catalyst and activator (polymerization initiator) is initiated very quickly, curing may occur before the solution is sufficiently flowed into the molding die. The monoether and / or monoester of a glycol compound selected from alkylene glycol or polyalkylene glycol is preferably used as the activity modifier. When injecting into the mold, the mold temperature is usually set in the range of 40 to 130 ° C.
It is preferable to carry out the polymerization reaction for 5 minutes.

In the manufacturing method of the present invention, when the fiber reinforcement is placed in advance in the mold, the mold cavity is depressurized in order to improve the permeation of the monomer into the fiber reinforcement. It is preferable.

Further, in order to improve the adhesive strength at the interface between the fiber reinforcing material and the matrix resin, the surface of the fiber reinforcing material may be subjected to a surface treatment after being coated with a metal. For example, when the matrix resin is RIM nylon or cyclopentadiene, a silane coupling agent or the like is effective. In addition, it is also preferable to perform a surface treatment with an alcohol-soluble, water-soluble or a nylon surface treatment agent that is soluble in both alcohol and water from the viewpoint of improving the adhesive strength.
In particular, by coating the fiber reinforcing material with a metal, a surface treatment agent can be arbitrarily selected according to the coating metal, and it is possible to select a surface treatment agent that does not contain or does not generate a compound that causes polymerization inhibition. .

[0028]

As described above, in the fiber reinforced plastic according to the present invention, the surface of the fiber reinforced material is coated with a metal so that the matrix resin is impregnated into the fiber reinforced material by reaction injection molding or resin transfer molding. However, when it reacts and solidifies, it is possible to suppress factors that hinder the polymerization, and to mold so that imperfect polymerization does not occur.

Specifically, (a) when the fiber reinforcing material contains the above-mentioned polymerization inhibiting compound, the compound can be blocked by a coating metal so as not to become a factor of polymerization inhibition during the reaction. . (b) When the component contained in the fiber reinforcement generates the above-mentioned polymerization inhibitor compound when reacting with the resin, the metal coating blocks the reaction of the component contained in the fiber reinforcement with the resin. Therefore, it is possible to prevent the formation of the polymerization inhibiting compound during the reaction. (c) The thermal conductivity can be increased. (d) Since the metal coating is applied, it is possible to reduce the influence of the sizing agent which generates or contains the polymerization inhibitor compound. (e) The surface of the metal coated with the fiber reinforcing material may be treated with a surface-treating material that does not inhibit polymerization, and the adhesive strength at the interface with the resin can be increased.

Since the polymerization inhibition is not generated as described above, it is possible to use fibers which could not be used because of the polymerization inhibition conventionally, and the original constituent material is used for the polymerization inhibition. It is possible to improve the physical properties of the fiber-reinforced plastic for which the strength and rigidity of the fiber-reinforced plastic were not obtained.

Further, by coating the surface with a metal, the rigidity of the fiber itself can be improved, so that the following effects can be obtained. (a) In the case of a method in which the reinforcing fibers are arranged in the mold in advance and the monomer is injected into the mold, if the rigidity of the fiber is low, the pressure of the injected monomer easily causes the fibers to move,
The fiber shape does not match the design, and the physical properties also vary. However, the metal coating suppresses the movement of fibers, and the rigidity and strength as designed can be obtained. (b) In the case of a method in which a length-adjusted reinforcing fiber is filled in a monomer forming a matrix by reaction injection molding or resin transfer molding, and simultaneously injected into a mold, the increase in fiber rigidity causes Bending is reduced, and it is possible to stabilize the physical property values and improve the physical property values.

Furthermore, by coating with a metal, the thermal conductivity can be improved and heat can be stored, and the shortage of heat quantity, which is one of the factors inhibiting polymerization, can be eliminated. In particular, since the fiber reinforcement has a low thermal conductivity, the thicker the wall, the more the heat inside the bulk of the fiber tends to be insufficient, and it is necessary to raise the temperature. The rate is improved, and it is possible to prevent a decrease in the polymerization rate due to insufficient heat. In addition, the metal coating enables the molded product to have an electromagnetic wave shielding function.

[0033]

EXAMPLES Examples of the present invention will be described below. In the first embodiment, the fiber reinforcement is preliminarily nickel-plated by electroless plating to provide a metal coating, the metal coated fiber reinforcement is placed in a mold, and RIM nylon is injected into the mold. Then, a fiber-reinforced plastic molded product is obtained by reaction injection molding.

More specifically, a plain weave cloth made of aromatic polyamide fiber (Technolar manufactured by Teijin Ltd., fiber HM-50 cloth product number, MF1000) is used as a fiber reinforcing material. After the oil agent adhering to the fiber spinning for the flat fiber cloth is removed by washing with a surfactant, nickel plating is performed by electroless plating as described above.

The above-mentioned nickel-plated plain weave cloth is used for a flat plate mold (in this embodiment, 300 mm × 150 mm ×
Planned multiple pieces (21 sheets in this embodiment) inside the thickness of 4 mm)
The mold is clamped, the mold is clamped, the inside of the mold is heated to 150 ° C., and the inside of the cavity is depressurized.

Inside the mold, a RIM nylon containing a polymerization catalyst melted at 90 ° C. and a polymerization initiator (Ube Industries U
Inject X-21). Specifically, the required amount of RIM nylon is divided into two containers, a polymerization catalyst is added to one of them, and a polymerization initiator and an activity modifier are added to the other to prepare two kinds of stable reaction solutions. is doing. The two types of reaction solutions are instantaneously mixed by a mixing head of a two-liquid reaction injection molding apparatus, and the mixed solution is immediately poured into the mold heated to 150 ° C.

The mixed solution injected into the mold causes a reaction while impregnating the fiber reinforcing material arranged in advance in the cavity. After the polymerization reaction is performed for 1 to 5 minutes to complete the solidification of the mixed liquid, the mold is opened and the molded fiber-reinforced plastic molded product is taken out.

The molded product manufactured by the above method is shown in FIG.
As shown in the enlarged view of FIG. 1, the surface of the fiber reinforcement 1 is coated with the metal 2, and the fiber reinforcement 1 coated with this metal 1
Are adhered to each other and filled with the matrix resin 3. The fiber content in the molded article of this example is 45%.

It should be noted that the content of the fiber reinforcement can be controlled by changing the filling amount of the fiber reinforcement placed in the mold during molding, and the shape of the cavity of the mold can be changed. The molded product can have any shape.

In the second embodiment, a metal coating is provided on the fiber reinforcing material by a sputtering treatment, the fiber-metal material coated with the metal is placed in a mold, and a dicyclopentadiene monomer is injected into the mold to react. An FRP molded product is obtained by the injection molding method.

More specifically, a plain weave cloth made of aromatic polyester fibers (Kuraray's Vectran, fiber HT, cloth product number AF1513) is used as the fiber reinforcement, and the oil agent attached to the plain weave cloth for fiber spinning is used as a surfactant. After being washed with, dried, and coated with stainless steel by a sputtering process.

The above-mentioned sputtering process creates a high-density plasma discharge using an electric field and a magnetic field near a target material placed in a vacuum, and ionizes gas ions.
(For example, argon gas) is accelerated by the electric field and collides with the target, and the energy thereof causes the target element to be knocked out in the form of molecules or atoms and adhere to the surface of the fiber reinforcement placed in a vacuum. Incidentally, in this embodiment, the stainless steel is coated by the sputtering process,
Other than stainless steel, Ti and Cu are also preferably used.

As described above, after coating the surface of the fiber reinforced material with a metal, in order to improve the adhesive strength at the interface with the resin, an epoxy silane coupling agent (KB, manufactured by Shin-Etsu Chemical Co., Ltd.
The surface treatment is performed according to M-403).

The same number of fiber reinforced materials which have been subjected to the above-mentioned metal coating and surface treatment are stacked in the same flat mold as in the first embodiment, and clamped. Next, in this embodiment, the temperature inside the mold is raised to 70 ° C. and the pressure inside the cavity is reduced.

Then, the dicyclopentadiene monomer
(METHON manufactured by Teijin Hercules) is poured into the mold, and the mixture is reacted and solidified at a polymerization reaction time of 90 seconds and molded by a reaction injection molding method. The molded product is the same as that of the first embodiment shown in FIG. 1, and the fiber content is also the same.

In the third embodiment, a fiber reinforcing material in which each carbon fiber filament is uniformly coated with nickel is placed in a mold, and RTM (resin transfer molding) epoxy is injected into the mold to form fibers. This can be said by obtaining a molded product of reinforced plastic.

More specifically, one carbon fiber filament 1
A plain weave cloth (Besfight MC cloth product number W3101 manufactured by Toho Rayon Co., Ltd.) in which the book is uniformly coated with nickel is used as a fiber reinforcing material. Plural pieces of this cloth are placed inside the flat plate mold, and the mold is clamped.
The temperature is raised to 50 ° C. and the inside of the cavity is depressurized.

Epoxy resin for RTM inside the mold
(Yukaka Shell Epoxy Co., Ltd. Epon # 9400) is injected. Specifically, Epon resin 9400 and Epon curing agent 9450 are mixed and injected at a ratio of 100: 31.5.
After the polymerization reaction time is about 10 minutes, the molded fiber-reinforced plastic molded product is taken out.

In the fourth embodiment, the RIM nylon monomer is filled with a fiber reinforcement made of polyamide fiber coated with nickel plating and having a short fiber length of several millimeters, and this fiber reinforcement is filled. Injecting the monomer into the mold, raising the temperature inside the mold in the same manner as in the above example, and
The pressure is reduced and a fiber reinforced plastic product is molded by the reaction injection molding method.

[0050]

Experimental Example A test was conducted to compare the performance of the fiber-reinforced plastic according to the present invention with that of a conventional fiber-reinforced plastic using a fiber-reinforced material not coated with a metal.

That is, a molded article of a comparative example made of the same matrix resin was formed by using the same fiber reinforcing material as in the first embodiment except that the fiber reinforcing material was not plated with nickel. The molded articles of the comparative example and the first example were each cut into a width of 10 mm to prepare a test piece having a width of 10 mm, a length of 150 mm and a thickness of 4 mm. JIS-K7 with sample support length of 80 mm for these test pieces
A 055 three-point bending test was performed to measure the bending elastic modulus and bending strength.

The results of the above tests are shown in Table 1 below. The nickel-plated fiber reinforced material according to the first embodiment of the present invention is superior in flexural modulus and flexural strength to the comparative example. It was demonstrated that the effect of the metal coating was excellent.

[0053]

[Table 1]Flexural modulus (kg / mm ² ) Bending strength (kg / mm ² )  1st Example 1540 29.0 Comparative Example 430 7.7

[0054]

As is apparent from the above description, according to the present invention, in the fiber reinforced plastic molded by the reaction injection molding or the resin transfer molding, the fiber reinforced material is preliminarily metal-coated. It is possible to exclude or suppress factors that cause polymerization inhibition during the reaction with the reaction raw material liquid. Therefore, it becomes possible to use a fiber reinforced material and a resin that could not be used due to occurrence of polymerization inhibition. For example, a fiber reinforced material and a resin excellent in impact resistance and vibration absorption are used in combination. be able to.

For example, RIM nylon is excellent in vibration absorption and RIM cyclopentadiene is excellent in impact resistance. Therefore, depending on the intended use of the molded product, the resin and the fiber reinforced material to be combined with the resin are used to inhibit polymerization. Can be selected and combined without causing any problem. Therefore, it can be preferably used as a protective material such as a helmet that requires vibration absorption and impact resistance, an automobile part such as a bumper, and a molding material such as a vibration damping material and an electromagnetic wave shielding material.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a fiber reinforced plastic according to the present invention.

[Explanation of symbols]

 1 Fiber reinforcement 2 Coated metal 3 Matrix resin

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location B29C 70/10 // B29K 105: 08

Claims (3)

[Claims] 1. A fiber reinforced plastic comprising a fiber reinforced material whose surface is coated with a metal, and a matrix resin obtained by reaction injection molding or resin transfer molding. 2. A fiber reinforced material whose surface is coated with a metal in advance is placed in a mold, and then an unreacted raw material liquid is injected into the mold to react while impregnating the fiber reinforced material in the mold. A method for producing a fiber-reinforced plastic, which comprises molding by a reaction injection molding method or a resin transfer molding method which causes 3. A reaction injection molding method or a resin in which a fiber reinforcing material having a length adjusted and previously coated with a metal is filled in the monomer and the monomer containing the fiber reinforcing material is injected into a mold. A method for producing a fiber-reinforced plastic, which comprises molding by a transfer molding method.