Fiberglass sheets, thermoplastic resin composite materials with glass fibers, and methods for manufacturing these.

Abstract

DEPCT6901 / 09 / 2568 The purpose of the present invention is to provide a glass wool sheet using glass fibers. High-strength, thermoplastic resin composite material with glass fibers and higher stiffness than that of the fibers. Conventional glass, and methods for manufacturing thermoplastic resin composite materials. Thermoplastic resin composite material contains thermoplastic resin. Plastic and fiberglass. Fiberglass fibers have an average fiber diameter of 1 micrometer to 8 micrometers. The edges have an average fiber length of 300 micrometers to 600 micrometers and are included in the thermoplastic resin composite material. Plastic, and with a characteristic ratio of 50 or more;

Description

Glass wool sheet, thermoplastic resin composite material containing glass fiber, and manufacturing method thereof

[0001] The present invention relates to a glass wool sheet, a thermoplastic resin composite material containing glass fibers, and a method for producing the same.

[0002] Plastics are used in a wide variety of applications, taking advantage of their lightweight characteristics. However, due to their low elastic modulus, they are not often used as structural materials. Weight reduction is required in a wide range of fields, and in the automotive industry, for example, metals are being replaced with plastics to reduce fuel consumption through weight reduction. When used as a structural material, as mentioned above, plastics themselves have a low elastic modulus, so glass fiber and carbon fiber, which have high elasticity and strength, are used as reinforcing materials.

[0003] Such fiber-reinforced composite materials are used in a wide range of fields, including not only automotive parts but also electrical and electronic parts, aircraft parts, ship parts, and building materials. There is a demand for further weight reduction, and attempts have been made to make them thinner. However, the fiber diameter of glass fibers typically used as reinforcing materials is 10 to 18 μm. When producing thin-walled molded products with a thickness of 1 mm or less by injection molding, the fibers are difficult to disperse uniformly, which can lead to warping. Furthermore, the fibers may float to the surface, impairing the smoothness of the appearance. While this problem can be solved by reducing the fiber diameter of the glass fibers to a few μm, stable production is not possible without a significant reduction in productivity, resulting in a significant increase in costs.

[0004] Examples of glass fiber include glass fibers produced by the mechanical winding method and glass wool produced by the centrifugal or flame method. Glass wool is more economical than glass fibers and can be produced with a fiber diameter as small as several micrometers. Patent Document 1 discloses a composite forming material that solves the problems encountered when producing thin-walled molded products by injection molding. The composite forming material is produced by kneading short glass fibers produced by the centrifugal and / or flame methods, with an average fiber length of 300 to 1000 μm and a fiber diameter of 3 to 6 μm before kneading, with a thermoplastic resin. Furthermore, Patent Document 2 discloses a method for producing a composite forming material, characterized in that, to improve the reinforcing effect, the short glass fibers are heated to a temperature of −150 to +50°C relative to the thermoplastic resin temperature and then added to the thermoplastic resin.

[0005] Because the glass wool described in these documents is bulky, it is first cut into 300 to 1000 μm pieces using a cutter mill or the like to increase the bulk density before being fed into a twin-screw extruder or the like. It is generally known that when a fiber material is used as a reinforcing material for a thermoplastic resin or the like, the greater the aspect ratio (fiber length / fiber diameter), which is the ratio of fiber length to fiber diameter, the better the reinforcing effect. In Patent Document 2, in order to increase the fiber length in the composite-forming material, the glass wool is heated in advance and then fed into the thermoplastic resin. However, the fiber length in the composite-forming material is at most 300 μm, and to further increase the reinforcing effect, the fiber length in the composite-forming material needs to be increased.

[0006] Patent Document 3 discloses a glass fiber reinforced resin composite material containing a thermoplastic resin and glass fibers produced by a wet molding process into the shape of sheets, blocks, or strips using glass fibers produced by a centrifugal method. However, the inventors have confirmed that even if the fiber length before mixing with the thermoplastic resin is made several times longer than in the prior art, the length of the glass fibers in the glass fiber reinforced resin composite material is not significantly improved, and the improvement in reinforcing effect is not sufficient.

[0007] Patent No. 5416620 Patent No. 5220934 Chinese Patent Application Publication CN112759794A

[0008] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a glass wool sheet using high-strength glass wool, a thermoplastic resin composite containing glass fiber and having higher rigidity than conventional materials, and a method for manufacturing the same.

[0009] The present inventors conducted extensive research to solve the above-mentioned problems and discovered that by effectively using compressed air during centrifugal glass wool production to rapidly cool the glass fibers, it is possible to produce glass fibers that are less likely to be cut by the shear force of a rotating screw when kneaded with a thermoplastic resin. They also discovered that by kneading this glass wool or glass wool sheet into a thermoplastic resin as a reinforcing material, a thermoplastic resin composite with high reinforcing properties can be produced, leading to the completion of the present invention. Specifically, the present invention encompasses the following: [1] A thermoplastic resin composite comprising a thermoplastic resin and glass fibers derived from glass wool, wherein the glass fibers have an average fiber diameter of 1 μm or more and 8 μm or less, an average fiber length of 300 μm or more and 600 μm or less, and an aspect ratio of 50 or more. [2] The thermoplastic resin composite according to [1], wherein the glass fibers have a fiber tensile strength of 900 MPa or more. [3] The thermoplastic resin composite according to [1], wherein a silane coupling agent is used as a surface treatment agent for the glass fibers. [4] The thermoplastic resin composite according to [3], wherein the amount of the silane coupling agent relative to the glass fiber is 0.2% by weight or more and 2.0% by weight or less. [5] The thermoplastic resin composite according to [1], which contains a surface coating agent as a surface treatment agent for the glass fiber. [6] The thermoplastic resin composite according to [5], wherein the amount of the surface coating agent relative to the glass fiber is 1.0% by weight or more and 5.0% by weight or less.[7] The thermoplastic resin is polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride, polystyrene (PS), polyvinyl acetate (PVAc), polytetrafluoroethylene (PTFE), acrylonitrile butadiene styrene resin (ABS resin), styrene-acrylonitrile copolymer (AS resin), acrylic resin (PMMA), polyamide (PA), polyacetal (POM), polycarbonate (PC), modified polyphenylene ether (m-PPE, modified PPE, PPO), polybutylene terephthalate (PTFE), polyisoprene (PC ... [8] A thermoplastic resin composite according to [1], which is composed of one or more of poly(vinyl alcohol), poly(ethylene terephthalate) (PBT), polyethylene terephthalate (PET), syndiotactic polystyrene (SPS), cyclic polyolefin (COP), polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), polysulfone (PSF), polyethersulfone (PES), liquid crystal polymer (LCP), amorphous polyarylate (PAR), polyetheretherketone (PEEK), thermoplastic polyimide (PI), and polyamideimide (PAI). [9] A glass wool sheet composed of glass wool containing glass fibers having an average fiber diameter of 1 μm or more and an average fiber length of 2000 μm or more and an average fiber length of 6000 μm or more, and a fiber tensile strength of 900 MPa or more, wherein the glass wool sheet has a thickness of 0.5 mm or more and an average fiber length of 1000 μm or more, and a density of 100 kg / m. ３ More than 300kg / m ３ [9] The glass wool sheet according to [8], which is manufactured by a wet paper-making method or a dry paper-making method.

[10] Glass wool sheet chips obtained by cutting the glass wool sheet according to [8] or [9] into approximately rectangular shapes with a side length of 2 to 30 mm.

[11] A method for manufacturing a thermoplastic resin composite, which contains a thermoplastic resin and glass fibers, and the glass fibers have an average fiber length of 300 μm or more and 600 μm or less, comprising the steps of: manufacturing glass wool containing glass fibers with an average fiber length of 2000 μm or more and 6000 μm or less; ３ More than 300kg / m ３A method for producing a thermoplastic resin composite, comprising: a step of producing a glass wool sheet as follows: a step of cutting the glass wool sheet into identical shapes to produce glass wool sheet chips; and a step of mixing the glass wool sheet chips with heated thermoplastic resin.

[0010] The thermoplastic resin composite of the present invention uses a glass wool sheet made of high-strength glass wool as a reinforcing material. In addition to the high strength of the glass wool itself, the high strength of the glass wool makes it less likely to break when added to a thermoplastic resin using an extrusion mixer or the like. The glass fibers contained in the resulting thermoplastic resin composite have a fiber length of 300 to 600 μm and are dispersed with an aspect ratio of 50 or greater. This results in improved physical properties, such as tensile strength, flexural strength, and impact strength, compared to conventional thermoplastic resin composites containing glass wool, enabling the composite to be used as a structural material, which is difficult to achieve with thermoplastic resin alone. High-strength glass wool can be produced, for example, by applying compressed air to the glass fibers during centrifugal production, effectively quenching and strengthening them.

[0011] Furthermore, the thermoplastic resin composite of the present invention uses a glass wool sheet as a reinforcing material, and since the fiber diameter is smaller than that of glass fiber, which is a common reinforcing material for thermoplastic resins, the glass wool is dispersed uniformly in the thermoplastic resin, improving warpage and surface smoothness, and therefore can be used for thin-walled electrical and electronic parts such as connectors and sockets.

[0012] FIG. 1 shows a schematic diagram of a glass fiberization apparatus (glass wool manufacturing apparatus) using a centrifugal method. FIG. 2 is a graph showing the relationship between the air-ring compressed air outlet distance A and the fiber tensile strength of glass wool. FIG. 3 is a graph showing the relationship between the air-ring compressed air outlet distance A and the fiber length of glass wool. FIG. 4 is a flow diagram explaining the process flow of glass wool sheet chipping. FIG. 5 is a photograph of the glass wool (a) of Patent Document 1 and the glass wool sheet chips (b) of the present invention before being kneaded with a thermoplastic resin. FIG. 6 is a graph showing the fiber length distribution of glass fibers in a polypropylene resin composite.

[0013] Below, we will explain a thermoplastic resin composite containing a glass wool sheet and glass fiber and a method for manufacturing the same, but the present invention is not limited to this explanation and those skilled in the art can make appropriate design modifications using conventional technology.

[0014] The present inventors have proposed a glass wool sheet using high-strength glass wool, which is produced by centrifugal production using compressed air to rapidly strengthen the glass fibers, thereby improving the tensile strength of the fibers and increasing the fiber length, a thermoplastic resin composite containing glass fibers, and a method for producing the same. Details are described below.

[0015] [Glass wool] In this specification, glass wool refers to a cotton-like material made of glass fibers, which is obtained by stretching glass molten at high temperature using centrifugal force or the like to form fine cotton-like fibers. The method for producing glass wool is not particularly limited, but for example, glass wool can be obtained by effectively applying compressed air during glass wool production using a centrifugal method to rapidly cool the glass fibers. By using this glass wool, the glass wool is less likely to be cut by the shear force of the rotating screw when kneaded with a thermoplastic resin, and the fibers can remain in the resin in a longer state.

[0016] The average fiber diameter of the glass fibers constituting the glass wool is 1 μm or more and 8 μm or less. Preferably, it is 2 μm or more and 7 μm or less, and more preferably, it is 3 μm or more and 6 μm or less. If the average fiber diameter is less than 1 μm, the economical manufacturing cost may be high. If the average fiber diameter is more than 8 μm, the fiber tensile strength may not be high, and the reinforcing effect may be insufficient.

[0017] The average fiber length of the glass wool is 2000 μm or more and 6000 μm or less. Preferably, it is 2500 μm or more and 6000 μm or less, and more preferably, it is 3000 μm or more and 6000 μm or less. If the average fiber length is less than 2000 μm, the fiber length in the thermoplastic resin composite becomes short, and sufficient reinforcing effect cannot be obtained. A longer fiber length is preferable because a higher reinforcing effect can be obtained. However, when producing a glass wool sheet by a wet papermaking method, when the glass wool is dispersed in a large amount of water (10 to 50 times by weight) to prepare a slurry, the fibers are cut by the stirring blade and the resulting water flow, resulting in an average fiber length of 6000 μm or less. The fiber tensile strength of the glass wool is 900 MPa or more. Preferably, it is 1000 MPa or more, and more preferably, it is 1100 MPa or more. If the fiber tensile strength is less than 900 MPa, the fibers will be cut and shortened by the shear force of the screw of the extrusion kneader, and a sufficient thermoplastic resin reinforcement effect will not be obtained. Examples of glass that is the raw material for the glass wool used in the glass wool sheet include, but are not limited to, recycled glass.

[0018] [Glass wool sheet and glass wool chips] In this specification, the glass wool sheet is a paper-made product produced by, for example, a wet paper-making method or a dry paper-making method using the glass wool. Therefore, the glass wool sheet is substantially composed of the glass fibers that make up the glass wool.

[0019] The thickness of the glass wool sheet is 0.5 mm or more and 3.0 mm or less. Preferably, it is 1.0 mm or more and 2.0 mm or less. If the thickness exceeds 3.0 mm, it becomes difficult to increase the density of the glass wool sheet, and the amount of air contained therein increases, increasing the risk of voids occurring in the thermoplastic resin composite. It is possible to increase the density of the glass wool sheet by high-pressure pressing after papermaking and before drying, but there is a risk that the fibers will break and become shorter during high-pressure pressing. The density of the glass wool sheet is 100 kg / m ３ More than 300kg / m ３ Preferably, it is 150 kg / m or less. ３ Above, 250kg / m３ The glass wool sheet can be cut into glass wool chips by appropriate means. The shape of the glass wool chips cut from the glass wool sheet of the present invention can be approximately rectangular, rectangular, or square. While the shape of the glass wool chips cut from the glass wool sheet of the present invention is not limited to approximately rectangular, the size of approximately rectangular glass wool chips is preferably 2 to 30 mm, more preferably 5 to 10 mm, per piece. If the piece length is less than 2 mm, the fiber length will be less than 2000 μm, resulting in insufficient reinforcement effect for the thermoplastic resin. If the piece length exceeds 30 mm, not only will the amount of fiber fed per hour to the extrusion mixer decrease, but the amount of fiber fed will vary greatly, resulting in inconsistent quality of the composite material. It is generally known that when a fiber material is used as a reinforcing material for thermoplastic resins, etc., the greater the aspect ratio (fiber length / fiber diameter), which is the ratio of fiber length to fiber diameter, the better the reinforcing effect. However, increasing the fiber length reduces the density of the glass wool and generates voids. In the thermoplastic resin composite material described herein, by forming the glass wool to be mixed with the thermoplastic resin into glass wool sheet chips, the density of the glass wool is increased, the occurrence of voids is suppressed, and the fiber length can be increased. Furthermore, because the glass wool sheet chips have a uniform shape, the amount fed into the twin-screw extruder is stable, and the quality of the thermoplastic resin composite material is stable. Figure 5 shows a photograph of glass wool before being mixed with the thermoplastic resin, Figure 5(a) shows a photograph of glass wool crushed with a cutter mill, and Figure 5(b) shows a photograph of glass wool sheet chips cut from a glass wool sheet with a cutting machine.

[0020] [Surface Treatment Agent] Glass wool is an inorganic material, while thermoplastic resin is an organic material, and therefore the adhesion between glass wool and thermoplastic resin is low. Therefore, it is preferable to surface treat the glass wool and then knead it with the thermoplastic resin.

[0021] Examples of the surface treatment agent for glass wool include a silane coupling agent and / or a surface coating agent. The silane coupling agent is not particularly limited as long as it is a conventionally used agent, and may be selected in consideration of the reactivity with the thermoplastic resin constituting the composite material, thermal stability, etc. Examples include aminosilane-based, epoxysilane-based, allylsilane-based, and vinylsilane-based silane coupling agents.

[0022] Examples of surface coating agents include known resins such as epoxy resins, vinyl acetate resins, vinyl acetate copolymer resins, urethane resins, and acrylic resins.

[0023] Examples of surface treatment methods for glass wool include a spray method in which a liquid containing a surface treatment agent is sprayed onto the glass wool, and a dipping method in which the glass wool is submerged in a liquid containing a surface treatment agent. The glass wool sheet of the present invention is coated with a silane coupling agent and / or surface coating agent as a surface treatment agent by dipping during the wet papermaking process. The amount of silane coupling agent applied to the glass wool sheet of the present invention is preferably 0.2 wt% or more and 2.0 wt% or less based on the glass wool. More preferably, it is 0.25 wt% or more and 0.4 wt% or less. If the amount of silane coupling agent is less than 0.2 wt%, the fiber surface may not be completely coated, which may impair adhesion to the thermoplastic resin. If the amount of silane coupling agent exceeds 2.0 wt%, excessive coating may occur, resulting in increased costs. The amount of surface coating agent applied to the glass wool sheet of the present invention is preferably 1.0 wt% or more and 5.0 wt% or less based on the glass wool. More preferably, it is 1.3 wt% or more and 3 wt% or less. If the amount of the surface coating agent is less than 1.0 wt%, there is a possibility that the fiber surface may not be completely coated, as in the case of a silane coupling agent, and there is a risk that the effect may be reduced. If the amount of the surface coating agent is more than 5.0 wt%, there may be an excessive coating, which may result in an increase in costs.

[0024] [Method of Manufacturing Glass Wool, Glass Wool Sheet, and Glass Wool Chips] First, a method of manufacturing glass wool will be described using a schematic diagram of a glass fiberizer (glass wool manufacturing apparatus) shown in FIG. 1 . Molten glass 1 is introduced into a spinner 2 having thousands to tens of thousands of small holes 22 of about 1 mm in a sidewall 21. When the spinner 2 is rotated at a high speed of 1,000 to 3,000 revolutions per minute, centrifugal force causes the molten glass 1 to be finely divided and ejected through the small holes 22, producing primary fibers 71. The produced primary fibers 71 (fiber diameters of tens to hundreds of μm) are finely fiberized by an LNG or LPG combustion gas jet, which is combusted in a combustion chamber 5 by a burner 3 and ejected from a burner gas jet outlet 4, to produce glass wool 7. The fiber diameter of the glass wool 7 is controlled by adjusting the temperature and speed of the burner gas jet, i.e., the combustion amount, and the temperature and speed of the burner gas jet are appropriately selected depending on the state of the fiberized glass. The produced glass wool 7 is cooled by compressed air blown downward from a number of air ring compressed air outlets 62, each about 1 to several mm in size, provided on the underside 61 of an air ring 6 installed outside the spinner 2, and is then led to a cotton collection conveyor (not shown) installed below the glass fiberization device D.

[0025] In Figure 1, A indicates the distance between the burner gas jet outlet 4 and the air ring compressed air outlet 62, which blows out compressed air. This distance is hereinafter referred to as the air ring compressed air outlet distance A. The air ring compressed air outlet distance A is 10 mm or more and 20 mm or less. Setting the distance to 20 mm or less increases the fiber tensile strength and length (Figures 2 and 3). When the air ring compressed air outlet distance A exceeds 20 mm, the fiber tensile strength and length do not change even when the compressed air pressure is changed. This indicates that the compressed air has little effect other than changing the glass wool flight direction (see Figures 2 and 3). If the distance is less than 10 mm, the spinner sidewall may be cooled, resulting in an increase in fiber diameter, or the molten glass inside the spinner may crystallize, clogging the spinner holes and hindering stable production. The air ring compressed air pressure is 0.1 MPa or more and 0.5 MPa or less.

[0026] An example of a method for manufacturing a glass wool sheet is shown in Figure 4. First, glass wool 7 is stirred and dispersed in water (S1). Next, the glass wool dispersed in water is placed on a mesh belt and transported while forming a glass wool sheet (S2). Here, a surface treatment agent such as a silane coupling agent and / or a surface coating agent is applied to the glass wool sheet by dropping or the like while being transported (S3), and the water is evaporated in a dryer to produce a dried glass wool sheet. The dried glass wool sheet is then cut into glass wool chips using a cutting machine or the like (S5).

[0027] [Thermoplastic resin composite] In this specification, the thermoplastic resin composite refers to a material obtained by integrally combining a thermoplastic resin with a material different from the thermoplastic resin, and in this specification, refers to a material obtained by combining a thermoplastic resin with glass fibers. The glass fibers contained in the thermoplastic resin composite are glass fibers derived from glass wool, glass wool sheets, or glass wool chips as defined in this specification.

[0028] The thermoplastic resin composite of the present invention is characterized by its high strength because it is reinforced with glass fibers. Specifically, the tensile strength, flexural strength, and impact strength are higher than those of conventional thermoplastic resin composites using glass wool, etc. The method for combining glass fibers and a thermoplastic resin is not particularly limited, and examples include a method of impregnating the fibers with a thermoplastic resin and a method of kneading the fibers with a thermoplastic resin. Among these, the method of kneading glass wool chips with a thermoplastic resin, as already explained, is preferred.

[0029] The thermoplastic resin composite of the present invention contains glass fibers having an average fiber length of 300 μm or more and 600 μm or less. The glass wool-derived glass fibers contained in the thermoplastic resin composite of the present invention are reinforced by effectively applying compressed air during glass wool production by centrifugal method to rapidly cool the glass fibers. When kneaded with the thermoplastic resin, they are less likely to be cut by the shear force of the rotating screw, allowing the fibers to remain in the resin in a longer state. The lower limit of the average fiber length of the glass fibers in the thermoplastic resin composite is preferably greater than 300 μm, more preferably 310 μm or more, even more preferably 320 μm or more, and even more preferably 330 μm or more. The longer the average fiber length, the greater the strength of the thermoplastic resin.

[0030] The average fiber diameter of the glass fibers constituting the glass wool is the same as the characteristics of the glass wool already described, and is 1 μm or more and 8 μm or less, preferably 2 μm or more and 7 μm or less, and more preferably 3 μm or more and 6 μm or less.

[0031] The aspect ratio of the glass fiber derived from glass wool in the thermoplastic resin composite is 50 or more, preferably 70 or more, and more preferably 100 or more. If the aspect ratio is less than 50, a sufficient reinforcing effect cannot be obtained. The shape of the molded product of the thermoplastic resin composite of the present invention is not particularly limited.

[0032] Thermoplastic resins that make up thermoplastic resin composites include polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinylidene chloride, polystyrene (PS), polyvinyl acetate (PVAc), polytetrafluoroethylene (PTFE), acrylonitrile butadiene styrene resin (ABS resin), styrene-acrylonitrile copolymer (AS resin), acrylic resin (PMMA), polyamide (PA), polyacetal (POM), polycarbonate (PC), modified polyphenylene ether (m-PPE, modified PPE, PPO), and polybutylene terephthalate (PTFE). phthalate (PBT), polyethylene terephthalate (PET), syndiotactic polystyrene (SPS), cyclic polyolefin (COP), polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), polysulfone (PSF), polyethersulfone (PES), liquid crystal polymer (LCP), amorphous polyarylate (PAR), polyetheretherketone (PEEK), thermoplastic polyimide (PI), polyamideimide (PAI), etc., with polypropylene (PP), polyacetal (POM), and liquid crystal polymer (LCP) being preferred. These may be used alone or in combination.

[0033] When producing a thermoplastic resin composite, the amount of glass wool added to be kneaded with the thermoplastic resin is 10% by weight or more and 60% by weight or less based on the total weight of the thermoplastic resin composite. The glass wool is preferably added in the form of glass wool chips.

[0034] Because thermoplastic resin composites use glass wool with a small fiber diameter as a reinforcing material, warping is suppressed when thin-walled molded products (for example, those with a thickness of 1 mm or less) are produced by injection molding, and the fibers do not protrude to the surface, impairing the smoothness of the appearance, making them suitable for thin-walled electrical and electronic parts such as connectors and sockets. Furthermore, when producing the glass wool using the centrifugal method, compressed air is effectively applied to rapidly cool and strengthen the glass fibers, improving the fiber tensile strength and lengthening the fiber length to form high-strength glass wool as a reinforcing material, resulting in improved physical properties such as tensile strength, flexural strength, and impact strength, enabling them to be used as structural materials that would be difficult to achieve with thermoplastic resin alone.

[0035] The thermoplastic resin composite is a material that combines glass fiber and thermoplastic resin, and may also contain additives such as known ultraviolet absorbers, stabilizers, antioxidants, plasticizers, colorants, tinting agents, flame retardants, antistatic agents, fluorescent brighteners, delustering agents, and impact strength improvers, provided that the object of the present invention is not impaired.

[0036] [Method for producing thermoplastic resin composite] The thermoplastic resin composite can be produced by melt-kneading a thermoplastic resin, the surface-treated glass wool sheet chips described above, and various additives added as needed, using a known melt-kneader such as a single-screw or multi-screw extrusion kneader, kneader, mixing roll, or Banbury mixer, at a temperature of, for example, 200 to 400°C. The production apparatus is not particularly limited, but melt-kneading using a twin-screw extrusion kneader is simple and preferable. The kneaded composite may be directly injection-molded into a mold, or may be pelletized and then injection-molded.

[0037] The method for producing a thermoplastic resin composite of the present invention includes a thermoplastic resin and glass fibers, and the average fiber length of the glass fibers contained in the thermoplastic resin composite is 300 μm or more and 600 μm or less. The method includes the steps of producing glass wool having an average fiber length of 2000 μm or more and 6000 μm or less, and a thermoplastic resin composite having a density of 100 kg / m3 and made from the glass wool. ３ More than 300kg / m ３This method for producing a thermoplastic resin composite includes the steps of producing a glass wool sheet (described below), cutting the glass wool sheet into identical shapes to produce glass wool chips, and kneading the glass wool chips with a heated thermoplastic resin. Examples of molding methods for the thermoplastic resin composite of the present invention include injection molding, hot press molding, hybrid molding, and blow molding. A detailed description is provided below, but the present invention is not limited to this description. The mixer temperature of a twin-screw extrusion kneader is heated to a predetermined temperature, and thermoplastic resin pellets are introduced into the twin-screw extrusion kneader through a sample inlet, and glass wool sheet chips are introduced into the twin-screw extrusion kneader through a side feeder equipped with a metering feeder. The composite pellets are then kneaded to produce a thermoplastic resin composite molded product. The glass wool sheet chips are introduced into the twin-screw extrusion kneader through a side feeder equipped with a metering feeder. However, the chips may be introduced vertically to the extrusion kneader via a screw feeder instead of the side feeder, or the metering feeder may be omitted.

[0038] The present invention will be described in detail below with reference to examples, but these examples are provided merely for the purpose of explaining the present invention and for reference of specific embodiments thereof. These examples are intended to illustrate specific specific embodiments of the present invention, but are not intended to limit or restrict the scope of the invention disclosed in this application.

[0039] Example 1 [Pellet Preparation] Polypropylene (PP) resin (Nakaseki Chemicals T30S) was used as the thermoplastic resin. The PP resin was maleated in advance by adding 2 wt% of Umex 1001 (manufactured by Sanyo Chemical Industries, Ltd.). The glass wool used as the reinforcing material was produced by a centrifugal method. During production, the air-ring compressed air outlet distance A was 15 mm, the compressed air pressure was 0.3 MPa, and the average fiber diameter was 3.0 μm. The centrifugal method was performed as follows: Molten glass 1 at 1100°C was introduced into spinner 2 at 300 kg / h, and spinner 2 was rotated at a high speed of 3000 rpm. A burner gas jet at a temperature of 1450°C was blown onto the produced primary fibers 71 to form fine fibers. Furthermore, fiber strength measurements for the examples and comparative examples herein were performed in accordance with "JIS R3420:2013 7.4 Constant-Speed ​​Load-Deformation Tensile Test Method."

[0040] The glass wool was prepared by a wet paper-making method, and the obtained glass wool was stirred and dispersed in water, placed on a mesh belt, and formed into a sheet. Epoxy silane (Silquest A-187, manufactured by Momentive Performance Materials) was applied to the formed sheet in an amount of 0.3% by weight relative to the glass wool, and the water was evaporated in a dryer at 200°C to produce a glass wool sheet. The density of the obtained glass wool sheet was 150 kg / m ３ , and the thickness was 2 mm.

[0041] The glass wool sheet was dried at 200° C. and then cut into chips of 5 mm square using a cutting machine. The average fiber length of the glass wool was 2520 μm.

[0042] Glass wool sheet chips were added to maleated polypropylene (PP) resin so that the ratio of the thermoplastic resin composite was 30 wt %, and the mixture was kneaded to prepare a thermoplastic resin composite (Example 1). The glass wool chips were added using a side feeder equipped with a quantitative feeder.

[0043] The resulting thermoplastic resin composite was heated at 500°C for 1 hour to burn off the PP resin, and the fiber lengths of 800 glass wool fibers were then measured using FASEP. The average fiber length was 510 μm, and the aspect ratio was 170. The measurement results are shown in Table 1 and Figure 6.

[0044] (Example 2) The glass wool production conditions were changed to an air ring compressed air outlet distance A of 10 mm and a compressed air pressure of 0.2 MPa, and glass wool with an average fiber diameter of 3.0 μm was produced. This glass wool was used to produce glass wool sheet chips in the same manner as in Example 1, and then a thermoplastic resin composite was produced. The average fiber length of the glass wool before mixing with the thermoplastic resin was 2910 μm.

[0045] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. As a result, the average fiber length was 545 μm and the aspect ratio was 181.7.

[0046] (Example 3) The glass wool production conditions were changed to an air ring compressed air outlet distance A of 20 mm and a compressed air pressure of 0.3 MPa, and glass wool with an average fiber diameter of 3.0 μm was produced. This glass wool was used to produce glass wool sheet chips in the same manner as in Example 1, and then a thermoplastic resin composite was produced. The average fiber length of the glass wool before mixing with the thermoplastic resin was 2320 μm.

[0047] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. As a result, the average fiber length was 468 μm and the aspect ratio was 156.

[0048] Comparative Example 1: The glass wool production conditions were changed to an air ring compressed air outlet distance A of 25 mm and a compressed air pressure of 0.3 MPa, and glass wool with an average fiber diameter of 3.0 μm was produced. This glass wool was used to produce glass wool sheet chips in the same manner as in Example 1, and then a thermoplastic resin composite was produced. The average fiber length of the glass wool before mixing with the thermoplastic resin was 1,890 μm.

[0049] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. As a result, the average fiber length was 283 μm and the aspect ratio was 94.3.

[0050] Comparative Example 2: Glass wool was produced under glass wool production conditions of an air ring compressed air outlet distance A of 25 mm and a compressed air pressure of 0.3 MPa, producing glass wool with an average fiber diameter of 3.0 μm. This glass wool was cut into an average fiber length of 950 μm using a cutter mill, and then a thermoplastic resin composite was produced in the same manner as in Example 1 using a twin-screw extruder kneader. Based on Patent Document 1, the silane coupling agent was applied using a spray nozzle in the same amount as in Example 1 immediately after fiberization.

[0051] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. As a result, the average fiber length was 128 μm and the aspect ratio was 42.7.

[0052] The fiber lengths and aspect ratios in the thermoplastic resin composite pellets produced in Examples 1 to 3 and Comparative Examples 1 and 2 are shown in Table 1.

[0053]

[0054] It was confirmed that by using fibers made by quenching glass wool as a reinforcing material, the average fiber length in the composite material was longer than that of conventional technology, and the aspect ratio was also significantly increased.

[0055] [Strength Test] The tensile strength (ASTM D638), flexural strength (ASTM D790), and impact strength (ASTM D256) of the thermoplastic resin composites produced in Examples 1 to 3 and Comparative Examples 1 and 2 were measured. Test pieces of the size specified by each strength test method were used. Specific strength tests are as follows. Note that all strength tests of the thermoplastic resin composites described in this specification were carried out according to the following method.

[0056] (Tensile strength) The tensile strength was measured in accordance with ASTM D 638. Using a universal testing machine Model AG-I manufactured by Shimadzu Corporation, the tensile strength of a test piece of the thermoplastic resin composite was measured under conditions of a pulling speed of 5.0 mm / min and a chuck spacing of 80 mm.

[0057] (Flexural Strength) Flexural strength was measured in accordance with ASTM D 790. Using a universal testing machine Model AG-I manufactured by Shimadzu Corporation, the flexural strength of a test piece of a thermoplastic resin composite was measured under conditions of a support distance of 64 mm and a head speed of 5.0 mm / min.

[0058] (Impact Strength) The impact strength was measured in accordance with ASTM D 256. The impact strength was measured by the Izod impact test method using a universal pendulum impact tester, Model 6545 / 000, manufactured by CEAST.

[0059] The results of each strength test are shown in Table 2. Each measured value is the average of five measurements.

[0060] The tensile strength, flexural strength, and impact strength were all greater than those of the comparative example, demonstrating an improved reinforcing effect. This is presumably because the glass wool was strengthened by rapid cooling, making the fibers less likely to break when the thermoplastic composite was produced in an extrusion kneader, resulting in longer fibers in the composite and a larger aspect ratio.

[0061] (Example 4) [Pellet Production] POM (Duracon M-90-44, manufactured by Polyplastics Co., Ltd.) was used as the thermoplastic resin. The glass wool used as the reinforcing material was produced under the conditions of an air ring compressed air outlet distance A of 15 mm and a compressed air pressure of 0.3 MPa, and the other conditions were the same as in Example 1 except for the burner gas jet temperature of 1400°C. The tensile strength of the glass wool was 1900 MPa and the average fiber diameter was 3.5 μm.

[0062] The glass wool was made into a sheet having a density of 200 kg / m by a wet papermaking method. ３ A glass wool sheet having a thickness of 1.0 mm was produced. As in Example 1, a surface treatment agent was applied by dipping during wet papermaking. The surface treatment agent was applied to the glass wool in amounts of 0.15 wt % each of aminosilane (Silquest A-1100, manufactured by Momentive Performance Materials) and epoxysilane (Silquest A-187, manufactured by Momentive Performance Materials), for a total of 0.3 wt %.

[0063] The glass wool sheet was dried at 200° C. and then cut into 8 mm square chips using a cutting machine. The average fiber length of the glass wool was 2860 μm.

[0064] A thermoplastic resin composite material containing 40% by weight of glass wool was prepared in the same manner as in Example 1, and the fiber length in the thermoplastic resin composite material was measured. The results are shown in Table 3.

[0065] (Example 5) The glass wool production conditions were changed to an air ring compressed air outlet distance A of 10 mm and a compressed air pressure of 0.2 MPa, and glass wool with an average fiber diameter of 3.5 μm was produced. Using this glass wool, a thermoplastic resin composite was produced in the same manner as in Example 4. The average fiber length of the glass wool before mixing with the thermoplastic resin was 2960 μm.

[0066] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. The results are shown in Table 3.

[0067] (Example 6) The glass wool production conditions were changed to change the position of the compressed air outlet of the air ring to 20 mm and the compressed air pressure to 0.3 MPa, and glass wool with an average fiber diameter of 3.5 μm was produced. Using this glass wool, a thermoplastic resin composite was produced in the same manner as in Example 4. The average fiber length of the glass wool before mixing with the thermoplastic resin was 2490 μm.

[0068] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. The results are shown in Table 3.

[0069] (Comparative Example 3) The glass wool was produced under the conditions of an air ring compressed air outlet position of 25 mm and a compressed air pressure of 0.3 MPa, producing glass wool with an average fiber diameter of 3.5 μm. This glass wool was used to produce a thermoplastic resin composite in the same manner as in Example 4. The average fiber length of the glass wool before mixing with the thermoplastic resin was 1720 μm.

[0070] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. The results are shown in Table 3.

[0071] Comparative Example 4 Glass wool having an average fiber diameter of 3.5 μm was produced under the same glass wool production conditions as in Comparative Example 3. The same amount of silane coupling agent as in Example 4 was applied in the same manner as in Comparative Example 2. This glass wool was cut into an average fiber length of 950 μm using a cutter mill, and then a thermoplastic resin composite material was produced in the same manner as in Example 4 using a twin-screw extruder kneader.

[0072] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. The results are shown in Table 3.

[0073] [Strength Test] The tensile strength (ASTM D638), flexural strength (ASTM D790), and impact strength (ASTM D256) of the thermoplastic resin composites produced in Examples 4 to 6 and Comparative Examples 3 and 4 were measured. Test pieces of the size specified by each strength test method were used. Table 3 shows the results of each strength test. Each measurement value is the average of five measurements.

[0074]

[0075] The tensile strength, flexural strength, and impact strength were all greater than those of the comparative example, demonstrating an improved reinforcing effect. This is presumably because, like the PP resin composite, the glass wool was strengthened by rapid cooling, making the fibers less likely to break when the thermoplastic composite was produced in an extrusion kneader, resulting in longer fibers in the composite and a larger aspect ratio.

[0076] (Example 7) [Pellet Production] A liquid crystal polymer (LCP) resin (manufactured by Polyplastics Co., Ltd., product number not disclosed) was used as the thermoplastic resin. The glass wool used as the reinforcing material was produced with an air ring compressed air outlet distance A of 10 mm and a compressed air pressure of 0.2 MPa, and the other conditions were the same as in Example 1 except for the burner gas jet temperature of 1350°C. The tensile strength of the glass wool was 1190 MPa and the average fiber diameter was 4.0 μm.

[0077] The glass wool was made by a wet papermaking method to a density of 250 kg / m ３A glass wool sheet having a thickness of 1.0 mm was prepared. As in Example 1, a surface treatment agent was applied by dipping during wet papermaking. The surface treatment agent consisted of 0.3 wt % epoxy silane (Silquest A-187, manufactured by Momentive Performance Materials) and 1.0 wt % epoxy resin (EM058, manufactured by ADEKA Corporation).

[0078] The glass wool sheet was dried at 200° C. and then cut into 10 mm square chips using a cutting machine. The average fiber length of the glass wool before being kneaded with the thermoplastic resin was 2930 μm.

[0079] A thermoplastic resin composite material containing 40% by weight of glass wool was prepared in the same manner as in Example 1, and the fiber length in the thermoplastic resin composite material was measured. The results are shown in Table 4.

[0080] (Example 8) The glass wool production conditions were changed to an air ring compressed air outlet distance A of 20 mm and a compressed air pressure of 0.3 MPa, and glass wool with an average fiber diameter of 4.0 μm was produced. Using this glass wool, a thermoplastic resin composite was produced in the same manner as in Example 7. The average fiber length of the glass wool before mixing with the thermoplastic resin was 2430 μm.

[0081] A thermoplastic resin composite was prepared in the same manner as in Example 7, and the fiber length in the thermoplastic resin composite was measured. The results are shown in Table 4.

[0082] (Example 9) The glass wool production conditions were changed to an air ring compressed air outlet distance A of 15 mm and a compressed air pressure of 0.3 MPa, and glass wool with an average fiber diameter of 4.0 μm was produced. Using this glass wool, a thermoplastic resin composite was produced in the same manner as in Example 7. The average fiber length of the glass wool before mixing with the thermoplastic resin was 2510 μm.

[0083] A thermoplastic resin composite was prepared in the same manner as in Example 1, and the fiber length in the thermoplastic resin composite was measured. The results are shown in Table 4.

[0084] Comparative Example 5: Glass wool with an average fiber diameter of 4.0 μm was produced under the glass wool production conditions of an air ring compressed air outlet distance A of 25 mm and a compressed air pressure of 0.3 MPa. Using this glass wool, a thermoplastic resin composite was produced in the same manner as in Example 7. The average fiber length of the glass wool before mixing with the thermoplastic resin was 1980 μm.

[0085] Comparative Example 6 Glass wool having an average fiber diameter of 4.0 μm was produced under the same glass wool production conditions as in Comparative Example 5. The silane coupling agent and surface coating agent were applied in the same amounts as in Example 7 using the same method as in Comparative Example 2. This glass wool was cut into an average fiber length of 950 μm using a cutter mill, and then a thermoplastic resin composite was produced in the same manner as in Example 7 using a twin-screw extruder kneader.

[0086] The fiber length in the resulting thermoplastic resin composite was measured in the same manner as in Example 1. The results are shown in Table 4.

[0087] [Strength Test] The tensile strength (ASTM D638), flexural strength (ASTM D790), and impact strength (ASTM D256) of the thermoplastic resin composites produced in Examples 7 to 9 and Comparative Examples 5 and 6 were measured. Test pieces of the size specified by each strength test method were used. Table 4 shows the results of each strength test. Each measurement value is the average of five measurements.

[0088]

[0089] The tensile strength, bending strength, and impact strength were all greater than those of the comparative example, and the reinforcing effect was improved.

[0090] According to the present invention, by increasing the strength of the glass wool through rapid cooling strengthening, the fiber length of the glass fiber contained in the thermoplastic resin composite can be made longer than that of conventional thermoplastic resin composites, thereby improving the physical properties of the thermoplastic resin composite. This is expected to not only broaden the range of applications of thermoplastic resin composites as structural materials, but also contribute to further reducing the thickness and weight of products.

[0091] DESCRIPTION OF SYMBOLS D Glass fiberizing apparatus (glass wool manufacturing apparatus) 1 Molten glass 2 Spinner 21 Side wall 22 Small hole 3 Burner 4 Burner gas jet outlet 5 Combustion chamber 6 Air ring 61 Underside 62 Air ring compressed air outlet 7 Glass wool 71 Primary fiber A Air ring compressed air outlet distance

Images