KR20210085208A - Method and apparatus for impregnating resin - Google Patents

Abstract

The present invention relates to a method and an apparatus for impregnating a resin, in which a powdered thermoplastic resin is dispersed and permeated into a reinforcing fiber substrate followed by heating and melting for primary impregnation of the thermoplastic resin; and laminating a thermoplastic resin film on one or both sides of the reinforcing fiber substrate impregnated with the primary resin followed by heating and melting for secondary impregnation of the thermoplastic resin. According to the present invention, it is possible to manufacture prepreg having excellent impregnation properties and excellent surface quality.

Description

Resin impregnation method and apparatus {METHOD AND APPARATUS FOR IMPREGNATING RESIN}

The present invention relates to a resin impregnation method and apparatus, and more particularly, to a resin impregnation method and apparatus capable of producing a prepreg having excellent impregnation property and excellent surface quality.

A fiber-reinforced composite material is a composite material impregnated with a resin in a reinforcing fiber base material, and is a material different from existing synthetic resin products in terms of physical properties.

For example, carbon fiber-reinforced plastic using carbon fiber as a reinforcing material is lightweight and has excellent strength and modulus, so it can be used as a component of sports and leisure products, as a material for vehicle aerospace, as a material for energy civil engineering and construction, etc. Its use is being developed.

Since a molded article obtained by molding a prepreg requires surface appearance quality, mechanical properties, etc., it is necessary to sufficiently impregnate the reinforcing fiber bundle with a resin to reduce voids as much as possible. Therefore, in the prepreg, a prepreg of a so-called complete impregnation type in which the reinforcing fiber bundle is almost completely impregnated with a thermoplastic resin has been demanded.

As a prior art for manufacturing a thermoplastic prepreg, a monomer (in-situ polymerization) method, a co-mingle method, an extruder method, and the like are known.

The monomer method is a method in which a low-viscosity thermoplastic resin monomer is uniformly impregnated between fiber substrates and then polymerized. In this method, due to the short polymerization time of 5 to 30 minutes, the polymer molecular weight is not large, so that the advantages of the thermoplastic resin cannot be faithfully used, and the physical properties are low.

The co-mingle method is a method of manufacturing a prepreg by uniformly mixing reinforcing fibers and thermoplastic fibers to prepare a co-mingled yarn, weaving it, and applying heat and pressure. However, some of the yarns of the reinforcing fibers with high modulus are broken during the combingle stage of the fiber base and thermoplastic fibers, and the damage to the yarns is large, which directly leads to deterioration of the performance of prepreg products. There are many problems with the limited use.

The extruder method is a method in which a thermoplastic resin is melted/discharged, directly applied on a reinforcing fiber substrate, and then impregnated using a hot-roller. However, since the thermoplastic resin has a high viscosity, it requires a high temperature of at least 200° C. for smooth impregnation. In particular, high heat-resistant thermoplastic resins require a high temperature of 350 to 400° C. or higher, and there is a lot of difficulty in manufacturing high-quality prepregs because of severe tar generation and stickiness due to oxidation at high temperatures. In particular, due to the high viscosity, it is difficult to uniformly impregnate the prepreg into the reinforcing fiber base material, so that it is difficult to exhibit sufficient performance due to the high porosity.

As another resin impregnation method, there is a film method in which a thermoplastic film is laminated on a reinforcing fiber substrate and impregnated with a resin by heating and pressing. In the case of a prepreg manufacturing process using the film method, the melt viscosity of the thermoplastic resin is very high, and the reinforcing fiber substrate It is difficult to uniformly impregnate the resin, and in order to produce a high-quality prepreg with a high degree of impregnation, there is a problem in that the production temperature must be excessively increased or the production speed must be set low. In addition, in order to lower the melt viscosity of the thermoplastic resin and improve the impregnation property, heating to a temperature much higher than the melting point of the resin film or increasing the high-temperature residence time by slowing the production rate, the resin may be thermally decomposed and the physical properties of the prepreg may be reduced. There are concerns. Due to the difficulty of impregnation, a low molecular weight resin film having a low melt viscosity is sometimes used despite the deterioration of physical properties, but in this case, the melt viscosity is lower than that of using a high molecular weight resin, which is advantageous for production , there is a problem in that mechanical properties are significantly reduced.

In Korean Patent No. 2014-0005409, a resin film having a high melt flow index and excellent impregnation property and a resin film having excellent mechanical properties due to a low melt flow index are sequentially supplied to at least one surface of a fiber base, and then heated and pressurized to form a prepreg. However, in this method, the manufacturing process is complicated because two types of thermoplastic resin films having different melt flow indexes are sequentially supplied and used, and in particular, in the first impregnation section, low viscosity to increase impregnation property. Since the film must be used, there is a problem in that the physical properties of the final composite material are deteriorated. In addition, since the crystallinity of the thermoplastic resin film is high, it is difficult to uniformly impregnate the thermoplastic resin in the fiber base, and during the pressing process, the fiber arrangement in the fiber base is deformed into an unintended shape, and there is a problem in that the physical properties are lowered.

The present invention is to solve the problems of the prior art described above, and one object of the present invention is to provide excellent surface quality while having excellent impregnation properties by uniformly dispersing reinforcing fibers even when using a high heat resistance resin having excellent mechanical properties. It is to provide a resin impregnation method and apparatus capable of manufacturing a prepreg product having

Another object of the present invention is to uniformly impregnate the reinforcing fiber substrate with a thermoplastic resin, and furthermore, increase the reinforcing fiber content of the prepreg, so that the fiber-reinforced composite material can have good physical properties and appearance. and to provide an apparatus.

One aspect of the present invention for achieving the above object is,

After impregnating the powdery thermoplastic resin into the reinforcing fiber base material and then heating and melting it, the thermoplastic resin is first impregnated into the reinforcing fiber base material, and then a thermoplastic resin film is laminated on one or both sides of the reinforcing fiber base material impregnated with the primary resin and heated and melted. It relates to a resin impregnation method, characterized in that the secondary impregnation of a thermoplastic resin into the reinforcing fiber substrate.

In the present invention, as the powdery thermoplastic resin used in the first impregnation step, particles having an average particle diameter of 1 to 20 μm may be used.

In the first impregnation step, heat-melting melts the powdered thermoplastic resin while passing through the heating section, and then repeats the process of pressing with a high-temperature roller several times to impregnate the thermoplastic resin into the reinforcing fiber.

Heat melting by the high-temperature roller is at least one set at various temperatures within the range of (T _g ) ℃ to (T _m +60) ℃ when the glass transition temperature of the thermoplastic resin is T _g and the melting cloud is T _{m .} It may be a step of heating and pressing step by step by means of a roller.

As the thermoplastic resin, a high heat-resistant thermoplastic resin having a melting point of 300° C. or higher may be used. Such high heat resistance resins include polyamide, polycarbonate, polybutylene terephthalate (PBT), polyetherimide (PEI), polyphenylene sulfide (PPS), polyether ketone ketone (PEKK), and polyether ether ketone (PEEK). ) and at least one selected from the group consisting of poly (methyl methacrylate) (PMMA) may be used.

The heat-melting process in the secondary impregnation step may be a step of further impregnating the thermoplastic resin on the film into the reinforcing fiber substrate by melting the resin film with a heating section and a high-temperature and high-pressure heating roller.

In the present invention, the reinforcing fiber may be glass fiber, carbon fiber, aramid fiber, boron fiber, alumina fiber, or silicon carbide fiber.

In the present invention, it is preferable to use the same thermoplastic resin as the powdered thermoplastic resin and the film-form thermoplastic resin, but different types of thermoplastic resins may be used if necessary.

When the same resin is used, the smaller the particles, the easier it is to impregnate the powder. Because the melt impregnation is carried out while penetrating between the filaments of the reinforcing fibers, the range of viscosity selection is very wide because the impregnation movement distance of the resin is short. Therefore, it is possible to apply resin products with high physical properties due to the large molecular weight. There is no particular limitation in the selection of the film form, and a product having the same or lower or higher molecular weight as the particulate form may be used.

In the case of using different thermoplastic resins, the melting point of the powdered thermoplastic resin should be similar to that of the film-type thermoplastic resin, and the compatibility and adhesiveness should be high.

Another aspect of the present invention for achieving the above object is,

An apparatus for impregnating a reinforcing fiber base material with a thermoplastic resin, the resin impregnating apparatus comprising:

a powder penetrating means for dispersing and penetrating the powdered thermoplastic resin into the reinforcing fiber substrate;

a first heating and pressing means for first impregnating the reinforcing fiber base material by heating and melting the powdered thermoplastic resin dispersedly infiltrated into the reinforcing fiber base material;

Film laminating means for laminating a thermoplastic resin film on one or both sides of the primary resin-impregnated reinforcing fiber substrate; and

It relates to a prepreg manufacturing apparatus comprising a second heating and pressing means for secondary impregnation of the thermoplastic resin in the reinforcing fiber substrate by heating and pressing the laminated thermoplastic resin film.

According to the present invention, in the case of manufacturing a prepreg composed of a reinforcing fiber and a thermoplastic resin having a high melting point such as PEEK, PEKK, or PPS, the powder impregnation method capable of ensuring excellent impregnation property and the film impregnation method having excellent surface quality are combined, A product having excellent impregnation property and excellent surface quality can be obtained.

According to the resin impregnation method and apparatus of the present invention, the reinforcing fiber bundle can be uniformly impregnated with the thermoplastic resin, and a high-quality fiber-reinforced composite material with few voids can be obtained.

1 is a schematic diagram of a prepreg manufacturing facility including a resin impregnation apparatus according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

The terminology used herein is used to describe specific embodiments, not to limit the present invention. As used herein, the singular forms may include the plural forms unless the context clearly dictates otherwise. Also, as used herein, "comprise" or "comprising

"comprising" specifies the presence of a recited shape, number, action, member, element, and/or group, and indicates the presence or addition of one or more other shapes, number, action, member, element, and/or group. It's not about exclusion.

The term "reinforced fiber bundle" used in the present invention is not particularly limited, such as its type or shape, but a single fiber bundle in which several single yarns are pulled side by side in a shape or a plurality of such fiber bundles are arranged side by side It means a bundle of fibers in the form of a sheet.

One aspect of the present invention is to impregnate a powdered thermoplastic resin into a reinforcing fiber substrate and then heat-melt it to first impregnate the thermoplastic resin into the reinforcing fiber substrate, and then apply a thermoplastic resin to one or both sides of the reinforcing fiber substrate impregnated with the primary resin. It relates to a resin impregnation method characterized in that a thermoplastic resin is secondary impregnated into a reinforcing fiber substrate by laminating a film and heating and melting the film.

In the present invention, as the thermoplastic resin, a high heat-resistant thermoplastic resin having a melting point of 300° C. or higher may be used. Such high heat-resistant thermoplastic resins include polyamide, polycarbonate, polybutylene terephthalate (PBT), polyetherimide (PEI), polyphenylene sulfide (PPS), polyether ketone ketone (PEKK), polyether ether ketone ( PEEK) and poly (methyl methacrylate) (PMMA) may be used at least one selected from the group consisting of, but is not necessarily limited thereto.

PEI resin has excellent adhesion to carbon fiber or glass fiber, and has a very high limit oxygen index of 47 in the state of a resin block, so it is excellent in strength and flame retardancy. PEEK resin has excellent chemical resistance and strength at high temperatures.

As the thermoplastic resin, polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polycyclohexanedimethyl terephthalate, and liquid crystal polyester, polyolefin resins such as polyethylene, polypropylene, and polybutylene, polyoxymethylene resins, and polyamide resins , polycarbonate resins, polyarylate resins, polymethyl methacrylate resins, polyvinyl chloride, ABS resins, AES resins, AAS resins, polystyrene water resins, styrene resins such as HIPS resins, modified polyphenylene ether (PPE) Resins, polyimide resins, polyetherimide resins, polysulfone resins, polyethersulfone resins, polyetherketone resins, phenol resins, phenoxy resins, their copolymers, modified products, etc. alone or in combination of two or more can also be used.

In the present invention, it is preferable to use particles having an average particle diameter of 1 to 20 μm for the powdered thermoplastic resin used in the first impregnation step. If the average particle diameter of the thermoplastic resin particles is too large than the filament diameter of the reinforcing fiber, there is a problem in that it cannot easily penetrate into the reinforcing fiber. In the present invention, the average particle diameter of the powdery thermoplastic resin particles can be measured by laser diffraction scattering method or the like.

A method of dispersing and permeating the powdery thermoplastic resin particles into the reinforcing fiber substrate is not particularly limited, and for example, the thermoplastic resin particles may be permeated into the reinforcing fiber substrate by air blowing. The method of air-blowing the thermoplastic resin particles is, for example, by discharging pressure air from an air outlet to permeate and disperse the thermoplastic resin particles into the reinforcing fiber substrate. Although there is no restriction|limiting in particular as for the pressure of the air used at this time, It can be made into about 0.3-2.0 MPa.

Before dispersing the powdery thermoplastic resin into the reinforcing fiber base material, it is preferable to open the reinforcing fiber bundle in advance. By opening in advance, the thickness of the reinforcing fiber bundle is made thin, the sizing agent binding many filaments is relieved, and the impregnability of the thermoplastic resin can be further improved by dispersing the filaments.

The opening method of the reinforcing fiber bundle is not particularly limited, and for example, a method of passing concave-convex rolls alternately, a method of using a drum-shaped roll, a method of applying tension fluctuations to axial vibration, and a method of vertically reciprocating 2 A method of varying the tension of a reinforcing fiber bundle by a dog friction body, a method of blowing air into a reinforcing fiber bundle, a method of sucking air into a reinforcing fiber bundle, a method of using a spring opening element, a method of using an expander roll, etc. method can be used. Moreover, it is also possible to use these two or more methods in combination.

After opening, a release paper or a release paper film may be arranged on the lower surface of the horizontally arranged reinforcing fibers, if necessary.

In the method of the present invention, after the powdered thermoplastic resin is dispersed and penetrated into the reinforcing fiber substrate, the powdered thermoplastic resin is melted through a high-temperature heating section, and then the process of pressing with a high-temperature roller is repeated several times to form the thermoplastic resin into the reinforcing fiber. First impregnated inside.

In the heating section, the reinforcing fiber substrate impregnated with the thermoplastic resin is heated by any heating means such as a heating plate, an IR lamp, or a halogen lamp. At this time, the heating temperature in the heating section is preferably performed at a temperature of 100 to 450 ℃ depending on the type of the thermoplastic resin. The additional heating and pressing step by means of a high-temperature roller is preferably performed at a temperature of 100 to 450 °C. The heating temperature in the heating section is preferably set to a temperature higher than the temperature of the heating process by the roller. That is, the heating temperature in the heating section and the heating and pressing step by the high-temperature roller overlap the temperature range, but the actual setting temperature causes the heating temperature of the heating section to be a higher temperature than the additional heating step by the roller.

The high-temperature and high-pressure heating roller is set at various temperatures within the range of (T _g ) ℃ to (T _{m +60) ℃ when the glass transition temperature of the thermoplastic resin is T g} and the melting temperature is T _m. It can be heated and pressurized step by step. For example, assuming that a resin having a glass transition temperature of 143°C and a melting point of 340°C is used, initially pressing at a temperature of 290°C and a pressure of 100 to 200 kgf/cm2, and gradually increasing the temperature and pressure The powdered thermoplastic resin can be impregnated into the reinforcing fiber substrate by compression at a temperature of 440° C. and a pressure of 300 to 400 kgf/cm 2 .

After the first impregnation of the powdery thermoplastic resin, a secondary impregnation of the film-like thermoplastic resin is carried out. That is, after laminating a film-like thermoplastic resin on one or both sides of the primary impregnated reinforcing fiber base material, the film is melted with a high-temperature heating section and a high-temperature and high-pressure heating roller to further impregnate the surface quality of the prepreg. make it

The thickness of the thermoplastic resin film used in the present invention is affected by the amount of pre-impregnated powdery resin because it determines the resin content of the final product by combining it with the amount of powder phase injected in the first impregnation step, but a thickness of about 5 μm to 10 μm It is suitable. When the thickness of the thermoplastic resin film exceeds 10 µm, the amount of resin is not sufficient in the first powder-phase impregnation process, making it difficult to uniformly and sufficiently impregnate the inside, and when the thickness is less than 5 µm, the thermoplastic resin film even under a small external force The resin film is easily torn, and fairness may be deteriorated.

Even during secondary impregnation, the thermoplastic resin on the film is melted with a high-temperature heating section and a high-temperature and high-pressure heating roller to further impregnate the thermoplastic resin into the reinforcing fiber substrate. At this time, the high-temperature and high-pressure heating roller is set to various temperatures within the range of (T _g )℃ to (Tm+60)℃ _{when the glass transition temperature of the thermoplastic resin is T g} and the melting temperature is T _m. It can be heated and pressurized step by step.

The reinforcing fibers used in the present invention are not particularly limited, and glass fibers, carbon fibers, aramid fibers, boron fibers, alumina fibers, silicon carbide fibers, and the like may be used. You may mix and use 2 or more types of this fiber. Among them, it is preferable to use carbon fibers from which a fiber-reinforced composite material of light weight and high rigidity is obtained. Among them, carbon fibers having a tensile modulus of elasticity of 230 to 800 GPa are preferably used.

In the present invention, the thermoplastic resin in the powder form and the thermoplastic resin in the film may use the same kind of thermoplastic resin, for example, the same kind of resin may be used although the molecular weight is different. Since the melt impregnation is carried out while penetrating between the filaments of the reinforcing fiber, the movement distance of the resin is short, so the choice of viscosity is very wide. Therefore, it is applicable to resin products that have high molecular weight and high physical properties, but are difficult to impregnate in film form due to high viscosity. It is possible. There is no particular limitation in the selection of the film form, and a product having the same or lower or higher molecular weight as the particulate form may be used.

Alternatively, different types of thermoplastic resins having compatibility or compatibility between the resins may be used. When different types of thermoplastic resins are used, a thermoplastic resin having a melting point similar to or higher than that of the film-type thermoplastic resin may be used. For example, a film-like thermoplastic resin is difficult to impregnate into a reinforcing fiber base material due to its high melt viscosity, but when a prepreg is prepared when a powder-like resin for reinforcing physical properties with excellent mechanical properties is used, both the degree of impregnation and the mechanical properties are excellent. Prepregs can be prepared.

In addition, in the film-type thermoplastic resin, within the range not impairing the effects of the present invention, elastomers, rubber components, flame retardants, inorganic fillers, conductivity improving components such as carbon black, crystal nucleating agents, ultraviolet absorbers, vibration dampers, antibacterial agents, Insect repellents, deodorants, colorants, pigments, dyes, heat stabilizers, mold release agents, antistatic agents, plasticizers, lubricants, foaming agents, foaming agents, coupling materials, and the like may be added.

The prepreg produced by the present invention preferably has a weight content of reinforcing fibers in the prepreg of 50 to 80% by weight, more preferably 60 to 70% by weight. If the fiber content is less than 60% by weight, the advantage of the fiber-reinforced composite material having excellent specific strength and specific modulus may not be obtained because the proportion of the resin is too large. On the other hand, when the fiber content exceeds 70% by weight, there is a fear that many voids are generated in the obtained fiber-reinforced composite material because impregnation of the resin is defective.

Since the prepreg produced by the present invention has excellent mechanical properties due to improved resin impregnation property, it is used for golf shafts, fishing rods, racquets such as tennis, badminton and squash, sporting goods such as sticks such as hockey and ski pole use, Structural materials for moving objects such as automobiles, ships and railroad vehicles, drive shafts, leaf springs, windmill blades, various turbines, pressure vessels, flywheels, paper rollers, roofing materials, cables, reinforcing bars, and civil construction materials such as reinforcing materials, etc. It can be suitably used for general industrial use and aerospace use.

Another aspect of the present invention relates to a resin impregnation apparatus. The resin impregnation apparatus of the present invention is an apparatus 400 for impregnating a reinforcing fiber base material with a thermoplastic resin, and the resin impregnating apparatus includes a powder penetrating means 410 for dispersing and penetrating a powdery thermoplastic resin into the reinforcing fiber base material; a first heating and pressing means 420 for first impregnating the reinforcing fiber base by heating and melting the powdered thermoplastic resin dispersedly permeated into the reinforcing fiber base; Film laminating means 430 for laminating a thermoplastic resin film on one or both sides of the primary resin-impregnated reinforcing fiber substrate; and a second heating and pressing means 440 for secondarily impregnating the laminated thermoplastic resin film into the heating and pressing reinforcing fiber substrate.

The means for penetrating the powdered thermoplastic resin 410 may be a means for blowing the powdery thermoplastic resin particles onto the reinforcing fiber substrate using air blow, but is not necessarily limited to this configuration.

The first heating and pressing means 320 is composed of a heating section and a high-temperature roller, the heating section is an IR lamp, an IR heating plate or a halogen lamp, the roller is the glass transition temperature of the thermoplastic resin T _g , the melting temperature When T _m , it may consist of one or more rollers set at various temperatures within the range of _{(T g )°C to (Tm+60)°C.} As the roller, a heating roller or a double belt press may be used.

The second heating and pressing means 440 is composed of a heating section and a high-temperature and high-pressure roller, and the second heating and pressing means 440 heats the thermoplastic resin film to a temperature above the melting point, thereby reinforcing the resin of the resin film as a fiber base material. melt impregnated in The heating section is an IR lamp, an IR heating plate, or a halogen lamp, and the roller is a glass transition temperature of the thermoplastic resin T _g , when the melting temperature is T _m , (T _g ) ℃ to (T _m +60) ℃ of It may consist of one or more rollers set to various temperatures within a range.

A prepreg manufacturing apparatus including the resin impregnation apparatus of the present invention and a prepreg manufacturing method by such an apparatus will be described as follows. 1 shows an apparatus for manufacturing a reinforcing fiber prepreg by impregnating a reinforcing fiber substrate with a resin.

1, the prepreg manufacturing apparatus including the resin impregnation apparatus of the present invention is an opening member 200, a supply member 300 such as a release paper or fabric, a resin impregnation device 400 and a winding device 500. can be configured.

In the prepreg manufacturing apparatus of the present invention, reinforcing fibers are released with a constant tension from the reinforcing fiber bobbin mounted on the creel stand 100 and then supplied to the carding member 200 .

A bobbin in which a reinforcing fiber bundle is wound is installed in the creel unit 100, and the reinforcing fiber bundle of the creel unit 100 is unwound while the bobbin rotates freely together with a mounting roller (not shown) in the creel unit 100, and is mounted By controlling the torque of the roller, the degree of unwinding (tension) of the reinforcing fiber bundle can be controlled. To this end, by installing a tension control device (not shown) or the like in each creel unit 100 , it is possible to control the tension at which the reinforcing fiber bundle is released through the torque control of the creel unit 100 .

On the other hand, the reinforcing fiber bundle (tow) supplied from the krill 100 is a yarn of inorganic fibers such as carbon fiber yarn, glass fiber yarn, aramid fiber yarn, silica fiber yarn, ceramic fiber yarn, ultra-high molecular weight polyethylene fiber yarn, etc. , Glass fiber yarn with excellent heat resistance is applied. As the carbon fiber, carbon fibers such as polyacrylonitrile (PAN)-based, petroleum/coal pitch-based, rayon-based, and lignin-based can be used.

If necessary, a release paper or a release film is supplied so that a release paper or a release film can be attached to the upper or lower surface of the reinforcing fibers that have passed through the opening member 200, or a fabric is supplied so that a fabric-type prepreg can be manufactured rather than a unidirectional prepreg, Alternatively, the member supply unit 300 including upper and lower supply rollers is installed so as to supply a mixture of yarn and fabric in one direction.

The powder penetrating means 410 for dispersing and infiltrating the powdery thermoplastic resin particles into the reinforcing fiber substrate is not particularly limited, for example, by discharging pressure air from the air outlet to permeate and disperse the thermoplastic resin particles into the reinforcing fiber substrate. It may be an air blower, alternatively it may be a means of uniformly applying the thermoplastic resin powder to the top of the reinforcing fiber substrate, or it may be impregnated and dispersed on the surface and inside through an aqueous dispersion solution, and other pressure or vacuum is applied. It may be a means to use.

The first heating and pressing means 420 is impregnated into the reinforcing fiber substrate by dissolving and pressing the resin particles after the powdered thermoplastic resin is dispersedly penetrated. The first heating and pressing means 420 includes a high-temperature heater and a high-temperature and high-pressure heating roller, which are sequentially arranged from the upstream to the downstream in the conveying direction of the powdery thermoplastic resin-impregnated fibers. The high temperature heater maintains a temperature higher than the melting point of the thermoplastic resin, and the high temperature and high pressure heating roller is set lower than the melting point or higher than the melting point depending on the situation.

The means 430 for laminating a film-like thermoplastic resin on the reinforcing fiber base material impregnated with the powdery thermoplastic resin first releases the resin film processed by processing the thermoplastic resin into a film form from a roll, and both sides of the reinforcing fiber base material impregnated with the primary resin (Upper surface and lower surface) Alternatively, a thermoplastic resin is laminated on one side.

In the second heating and pressing means 440 , a plurality of upper and lower pressure rollers for heating and pressing the resin film on the reinforcing fiber substrate are installed to face each other. The second heating and pressing device 440 heats/pressurizes the resin film to a temperature equal to or higher than the melting point, and melts and impregnates the thermoplastic resin in the film form into the reinforcing fiber substrate.

A cooling plate may be installed at the rear end of the second heating and pressing means. The cooling plate applies a constant pressure while cooling the resin impregnated in the reinforcing fiber bundle to form the reinforcing fiber into a film.

The winding device 700 takes up the dried fibers. It has a structure in which a pair of take-up rollers, which are positioned at the lower and upper parts of the take-up machine and face each other, are rotated by power, respectively. Therefore, the take-off machine pulls out the prepreg manufactured by the heating and pressing means 440 in the front.

In the case of manufacturing a prepreg according to the present invention, a reinforcing fiber bundle is supplied from the creel stand 100, and the reinforcing fiber base material is first impregnated with a powdery thermoplastic resin in the resin impregnation device 400, and then, in the form of a film The thermoplastic resin is impregnated, and thus, the resin-impregnated reinforcing fiber bundle is introduced into the second heating and pressing means 440 and dried by heating. The resin is secondarily impregnated into the reinforcing fiber bundle by the second heating and pressing means 440 . Since the temperature of the reinforcing fibers increases while passing through the heating in the secondary impregnation step, a step of naturally cooling at room temperature to lower the temperature thereof may be additionally included. Such a cooling step may be accomplished by injection of air, but is not limited thereto. A prepreg sheet is manufactured through this process, and the manufactured prepreg sheet passes between the take-up rollers of the take-up machine, and is wound around the take-up device 500 together with a protective film or release paper if necessary.

In addition, the prepreg manufactured using the resin impregnation apparatus of the present invention can provide a molded article having excellent mechanical properties. The molded article of the present invention is useful for various uses such as electric or electronic equipment, home or office equipment, entertainment equipment or entertainment products, optical equipment, precision machine-related parts, automobile-related, aircraft-related, sports-related, satellite-related, and the like. Among them, it can be preferably used for electric or electronic device cases, automobiles or aircraft members and outer plates.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are for illustration of the present invention, and are not intended to limit the scope of protection limited by the appended claims.

Example 1

Carbon fiber (Hyosung Tansome H2550 12K) was used as a fibrous substrate for the preparation of the prepreg, and 18 bobbins were used. As shown in FIG. 1, the fiber fibers unwound from the creel are released from the filaments while passing through the opening part to prepare a uniform web state with a width of 100 mm, and then, PEEK resin powder using a rotary particle feeder. (Victrex Vicote 704) was uniformly applied to the top and the inside of the carbon fiber substrate at a density of 8.5 g/m. Next, the reinforcing fibers were heated to 400° C. with an IR lamp, and pressed at a pressure of 200 kg/cm 2 by a heating roller heated stepwise to 290° C., 330° C., and 350° C. to first melt-impregnate the PEEK resin.

A PEEK film (Victrex 2000-016) having a thickness of 16 µm was laminated on both sides of the primary resin-impregnated carbon fiber fabric, and the second was pressurized at a pressure of 50 kg/cm by a heating roller heated stepwise to 290 and 330 °C. melt impregnated. After cooling by passing through an air cooling section of a plurality of channels having a pressure of 6 kgf/cm 2 , a thermoplastic prepreg was prepared.

The impregnation property and surface quality of the prepared prepreg were evaluated, and the results are shown in Table 1 below.

Example 2

A prepreg was prepared in the same manner as in Example 1, except that a PEEK film was applied to only one side of the carbon fiber substrate impregnated with the primary resin during impregnation with the thermoplastic resin on the film, and the second impregnation was carried out in the same manner as in Example 1. The obtained prepreg was evaluated for impregnation property and surface quality, and the results are shown in Table 1 below.

Comparative Example 1

Except for the process of impregnating by applying the thermoplastic resin on the film, the prepreg was prepared only by the one-step impregnation process on the powder. However, the amount of powder applied was 9.8 g/m. The impregnation property and surface quality of the prepared prepreg were evaluated, and the results are shown in Table 1 below.

Comparative Example 2

A PEEK film with a thickness of 28 μm is laminated on both sides of the carbon fiber fabric, and the PEEK film is heated to 320° C., and then pressed at a pressure of 200 kg/cm 2 by a heating roller heated stepwise to 290° C., 330° C., and 350° C. and melt-impregnated. Thereafter, the carbon fiber fabric was cooled by air cooling to prepare a thermoplastic prepreg.

The impregnation property and surface quality of the prepared prepreg were evaluated, and the results are shown in Table 1 below.

Comparative Example 3

Thermoplastic prepregs were prepared using the extruder method. The resin was melted to 400°C and discharged into the impregnation die, and the opened yarn was impregnated through the impregnation die and then further impregnated with a high-temperature and high-pressure roller.

test example

For the prepregs prepared in Examples and Comparative Examples, impregnation properties and surface quality were evaluated by the following method.

(1) reinforcing fiber content

After cutting the prepared prepreg to 100 mm in length x 100 mm in width, the weight (w1) is measured. The sample was divided into 4 equal parts and placed in a crucible whose weight (w2) was measured in advance, and the combined weight (w3) of the crucible and the sample was measured, and then placed in a furnace (Muffle Furnace). Thereafter, the temperature was raised to 580° C. in a nitrogen atmosphere in 2 hours, maintained for 24 hours, and then taken out after cooling for 3 hours, and the weight (w4) of the sample after sintering with the crucible was measured. The content (wt%) of the reinforcing fibers was calculated as (w4-w2)/(w1)×100.

(2) impregnability

The impregnation property in the present invention refers to the ease of penetration of the thermoplastic resin into the reinforcing fiber when the thermoplastic resin is heated and molded in a molten state. In the present invention, the prepared prepreg is cut into a length of 100 mm x width of 10 mm to obtain a test sample. The impregnability of each sample was evaluated in four steps according to the following criteria.

-Excellent: Almost no voids can be seen

-Good: The void area with respect to the cross-sectional area of the prepreg is 10% or less.

-Normal: The void area with respect to the cross-sectional area of the prepreg exceeds 10%.

- Defect: The void area with respect to the cross-sectional area of the prepreg exceeds 50%.

(3 ) Surface quality

Surface quality was evaluated by hair growth and surface roughness by sensory evaluation of 10 experts.

(4) surface irregularities

The width direction surface roughness (irregularity) of the sample was measured using a roughness meter (Mitsutoyo SJ-210). The cut-off length was 0.8㎛, the sampling length was 25mm, the number of measurement sections was 5, and the measurement speed was 0.5mm/s, and a Gaussian filter was applied as the filter. After 10 measurements, the surface roughness was compared with the Ra and Rz values.

reinforcing fiber
Impregnation amount (wt%) Average thickness (㎛) impregnability surface
elegance Ra
(μm) Rz
(μm) mean ± deviation Comparative Example `1 60±4% 155 Great Inadequate 3.77 24.51 Comparative Example 2 54±2% 173 bad Inadequate 1.53 11.32 Comparative Example 3 64±4% 154 Good bad 5.70 31.35 Example 1 53±2% 175 Great Great 1.02 4.70 Example 2 58±3% 160 Great Great 2.28 15.05

As can be seen through the results of Table 1, it can be seen that the prepregs prepared in Examples 1 and 2 are uniformly impregnated with the thermoplastic resin in the reinforcing fiber substrate, and it can be confirmed that the surface quality is excellent. In addition, the prepreg prepared according to the present invention had a reinforcing fiber content of (53)% or more based on the total weight of the prepreg.

In the above, the present invention has been described in detail only with respect to the described embodiments, but it is apparent to those skilled in the art that various changes and modifications are possible within the scope of the technical spirit of the present invention, and it is natural that such variations and modifications belong to the appended claims. .

100: krill 200: opening part
300: member supply unit 400: resin impregnation device
410: powder penetration means 420: first heating and pressing means
430: film lamination means 440: second heating and pressing means
500: winding device

Claims (14)

After impregnating the powdery thermoplastic resin into the reinforcing fiber base material and then heating and melting it, the thermoplastic resin is first impregnated into the reinforcing fiber base material, and then a thermoplastic resin film is laminated on one or both sides of the reinforcing fiber base material impregnated with the primary resin and heated and melted. A resin impregnation method, characterized in that the thermoplastic resin is secondary impregnated into the reinforcing fiber substrate.
According to claim 1, wherein the powdered thermoplastic resin used in the first impregnation step has an average particle diameter of 1 ~ 20㎛ Resin impregnation method, characterized in that the particles.
According to claim 1, wherein the heat melting in the first impregnation step is the step of impregnating the thermoplastic resin into the reinforcing fiber while repeating the process of melting the powdered thermoplastic resin through a heating section and then pressing with a high-temperature roller several times. Resin impregnation method, characterized in that.
According to claim 3, wherein the heat melting by the high-temperature roller, when the glass transition temperature of the thermoplastic resin is T _g and the melting point is T _m , (T _g ) ℃ to (T _m +60) ℃ within the range of various Resin impregnation method, characterized in that the step of heating and pressing step by step by one or more rollers set at a temperature.
The method of claim 1 , wherein the thermoplastic resin uses a high heat-resistant thermoplastic resin having a melting point of 300° C. or higher.
According to claim 5, wherein the thermoplastic resin is polyamide, polycarbonate, polybutylene terephthalate (PBT), polyetherimide (PEI), polyphenylene sulfide (PPS), polyether ketone ketone (PEKK), polyether It is characterized in that at least one selected from the group consisting of ether ketone (PEEK) and poly (methyl methacrylate) (PMMA) is used.
The method according to claim 1, wherein the heat-melting process in the secondary impregnation step is a step of further impregnating the reinforcing fiber substrate with a thermoplastic resin by heat-melting the resin film with a heating section and a high-temperature and high-pressure heating roller.
The resin impregnation method according to claim 1, wherein the reinforcing fibers are glass fibers, carbon fibers, aramid fibers, boron fibers, alumina fibers, or silicon carbide fibers.
The resin impregnation method according to claim 1, wherein the powdered thermoplastic resin and the thermoplastic resin film use the same kind of thermoplastic resin.
The resin impregnation method according to claim 1, wherein the thermoplastic resin film uses different types of thermoplastic resins, and the melting point of the powdered thermoplastic resin is similar to or higher than that of the film-type thermoplastic resin.
A device for impregnating a reinforcing fiber substrate with a thermoplastic resin, wherein the resin impregnating device comprises:
a powder penetrating means for dispersing and penetrating the powdered thermoplastic resin into the reinforcing fiber substrate;
a first heating and pressing means for first impregnating the reinforcing fiber base by heating and melting the powdered thermoplastic resin dispersedly permeated into the reinforcing fiber base;
Film laminating means for laminating a thermoplastic resin film on one or both sides of the primary resin-impregnated reinforcing fiber substrate; and
and a second heating and pressing means for secondarily impregnating the thermoplastic resin in the reinforcing fibers by heating and pressing the laminated thermoplastic resin film.
[Claim 12] The method of claim 11, wherein the means for penetrating the powdered thermoplastic resin gives a minute vibration of the reinforcing fibers while supplying a fixed amount of dry powder with a rotary needle roll and a vibrating brush, or permeates the reinforcing fibers into the inside of a sealed container. Prepreg manufacturing, characterized in that the particles in the space are circulated by injecting air while supplying the powder to penetrate the surface and inside of the reinforcing fiber, or the reinforcing fiber is passed through the aqueous dispersion or slurry of the resin while vibrating Device
The method of claim 11, wherein the first heating and pressing means is composed of a heating section and a high-temperature roller, the heating section is an IR lamp, an IR heating plate or a halogen lamp, the roller is the glass transition temperature of the thermoplastic resin T _g , melting point Prepreg manufacturing apparatus, characterized in that consisting of one or more rollers set at various temperatures within the range of (T _g ) °C to (T _m +60) °C when T _{m is.} 12. The method of claim 11, wherein the second heating and pressing means is composed of a heating section and a high-temperature roller, the heating section is an IR lamp, an IR heating plate or a halogen lamp, the roller is the glass transition temperature of the thermoplastic resin T _g , Prepreg manufacturing apparatus, characterized in that it is composed of one or more rollers set at various temperatures within the range of (T _g )°C to (T _m +60)°C when the melting point is T _{m .}

Images