Composition for vehicle wheel member, and molded body and wheel balance weight using the same

Abstract

To provide a composition and a molded article having excellent adhesion to a curved surface of a vehicle wheel and moldability. In addition, the present invention has been made in an effort to provide a composition capable of implementing excellent durability and a low wheel balancing error rate by having fatigue resistance against repeated bending that may occur during a product manufacturing process or a balancing operation.SOLUTION: According to an aspect of the present invention, there is provided a composition for a wheel member for vehicles, the composition including 1 to 30 parts by weight of a plasticizer and 400 to 1680 parts by weight of metallic particles, based on 100 parts by weight of TPU, wherein the TPU has a 3g / cm3 hardness of 59 to 92.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a composition for vehicle wheel components, a molded article using the same, and a wheel balance weight. [Background technology]

[0002] Wheel balance weights are installed to eliminate weight imbalances on vehicle wheels, rims, etc. These wheel balance weights are usually made of steel, but they can corrode due to environmental conditions where the wheel is exposed, high temperature and moisture intrusion conditions, and calcium chloride intrusion conditions in winter. They can also peel off or lift off due to insufficient adhesion to the curved surface of the wheel. They can also be difficult to precisely adjust, which can lead to excessive wheel balancing defects. They also lack fatigue resistance under repeated bending conditions, which can lead to breakage during the manufacturing process.

[0003] On the other hand, in the case of wheel balance weights using compositions mainly containing polyester-based resins, fatigue performance against repeated bending is insufficient, and cracks and breaks frequently occur during the production and application of molded products, resulting in reduced productivity. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Korean Patent Registration No. 10-1806741 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made to solve the above problems, and an object of the present invention is to provide a composition and a molded article having excellent adhesion and moldability to the curved surface of a vehicle wheel.

[0006] Another object of the present invention is to provide a composition that has fatigue resistance against repeated bending that may occur during product manufacturing processes or balancing operations, and can achieve excellent durability and a low wheel balancing error rate.

[0007] The objects of the present invention are not limited to the above-mentioned objects, but will become clearer from the following description and can be realized by the means and combinations thereof set forth in the claims. [Means for solving the problem]

[0008] A composition for a vehicle wheel member according to one embodiment of the present invention comprises 1 to 30 parts by weight of a plasticizer and 400 to 1680 parts by weight of metal particles based on 100 parts by weight of thermoplastic polyurethane, and has a density of 3 g / cm 3 The thermoplastic polyurethane may have a Shore A hardness of 59 to 92.

[0009] A molded article according to one embodiment of the present invention may include 400 to 1680 parts by weight of metal particles and a plasticizer, based on 100 parts by weight of thermoplastic polyurethane, and may have a density of 3.2 g / cm3 or more, and the Shore A hardness of the thermoplastic polyurethane may be 59 to 92. [Effects of the Invention]

[0010] The composition of the present invention is easily moldable, and a molded article to which the composition is applied can have excellent adhesion to the curved surface of a vehicle wheel.

[0011] Furthermore, molded articles using the composition of the present invention have fatigue resistance against repeated bending that may occur during the manufacturing process and balancing work in mass production of products, thereby improving the problem of reduced productivity.

[0012] Furthermore, when the molded product to which the composition according to the present invention is applied is applied to a wheel, the work defect rate can be improved by 50% or more compared to metal products.

[0013] Furthermore, the molded product using the composition according to the present invention can be precisely balanced in small amounts of 0.5 g, thereby achieving a low wheel balancing error rate, minimizing noise generation during vehicle driving and minimizing interference with the brake caliper.

[0014] Furthermore, molded articles using the composition according to the present invention can have excellent hydrolysis resistance in extreme heat and high temperature and humidity conditions, saltwater resistance against sodium chloride, calcium chloride, etc., and good weather resistance against ultraviolet rays, thereby exhibiting durability suitable for vehicle wheel components exposed to the external environment for long periods of time.

[0015] The effects of the present invention are not limited to those mentioned above, and should be understood to include all effects that can be inferred from the following description. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a photograph of a wheel balance weight to which a molding according to an embodiment of the present invention is applied and to which a film is attached. [Figure 2] 10 is a photograph showing a schematic diagram of a bending fatigue resistance test process in an experimental example. [Figure 3] 10 is a photograph showing the results of bending fatigue resistance tests of some examples in the experimental examples. [Figure 4] 1 is a photograph showing the results of a hydrolysis resistance test of Reference Example 6 in Experimental Examples. DETAILED DESCRIPTION OF THE INVENTION

[0017] The above and other objects, features, and advantages of the present invention can be easily understood by the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments described herein are provided so that the disclosure will be thorough and complete, and so that the concept of the present invention will be fully conveyed to those skilled in the art.

[0018] In the description of each figure, like reference numerals are used to denote like elements. In the accompanying drawings, the dimensions of structures are exaggerated for clarity of the present invention. Terms such as "first" and "second" can be used to describe various elements, but the elements should not be limited to these terms. The terms are used only to distinguish one element from another. For example, a first element can be called a "second element," and similarly, a second element can be called a "first element," without departing from the scope of the present invention. A singular term includes a plural term unless the context clearly dictates otherwise.

[0019] In this specification, the use of terms such as "comprise" or "have" is intended to specify the presence of a feature, numeral, step, operation, component, part, or combination thereof as described in the specification, and should be understood not to preclude the possibility of the presence or addition of one or more other features, numerals, steps, operations, components, parts, or combinations thereof. Furthermore, when a layer, film, region, plate, or other part is referred to as being "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where there is another part between them. Conversely, when a layer, film, region, plate, or other part is referred to as being "under" the other part, this includes not only the case where it is "directly under" the other part, but also the case where there is another part between them.

[0020] Unless otherwise expressly stated, all numbers, values, and / or expressions expressing quantities of ingredients, reaction conditions, polymer compositions, and formulations used herein should be understood in all instances to be modified by the term "about" because such numbers are inherently approximations that reflect, among other things, the various uncertainties of measurement that arise in obtaining such values. Also, when numerical ranges are disclosed below, such ranges are continuous and, unless otherwise indicated, include every value from the minimum value to, and including, the maximum value of such range. Furthermore, when such ranges refer to integers, they include every integer from, and including, the minimum value to, and including the maximum value, unless otherwise indicated.

[0021] Composition for vehicle wheel components A composition for a vehicle wheel component according to one aspect of the present invention comprises: A) Based on 100 parts by weight of thermoplastic polyurethane, B) 1 to 30 parts by weight of a plasticizer; C) 400 to 1680 parts by weight of metal particles, Density is 3g / cm 3 That's all, The thermoplastic polyurethane may have a Shore A hardness of 59 to 92.

[0022] The vehicle wheel member is a wheel balance weight, which is a member applied to adjust the wheel balance of a vehicle, and is a member attached to a part such as a wheel or a wheel rim, and can be attached to a curved part.

[0023] In addition to wheel components of vehicles, the composition may also be applied to wheel components of other means of transportation. In addition to wheel components, the composition may also be applied to compositions for components and parts that require similar physical properties such as bending fatigue resistance, weather resistance, corrosion resistance, and adhesion.

[0024] The thermoplastic polyurethane (TPU) A may be a thermoplastic elastomer having a predetermined elasticity. It may be derived by reacting A-1) any one of polyester polyols, polyether polyols, and combinations thereof, A-2) a diisocyanate-based compound, A-3) a compound containing hydrogen and an acid functional group capable of reacting with isocyanate, A-4) a hydroxyl group-containing siloxane-based compound, A-5) a silane coupling agent, and A-6) a crosslinking agent.

[0025] Illustratively, the thermoplastic polyurethane elastomer is A-1) Based on 100 parts by weight of any one polyol selected from polyester polyols, polyether polyols, and combinations thereof, A-2) 20 to 50 parts by weight of a diisocyanate compound; A-3) 2 to 15 parts by weight of a compound containing hydrogen and an acid functional group capable of reacting with isocyanate; A-4) 1 to 10 parts by weight of a hydroxyl group-containing siloxane compound; A-5) 0.3 to 5 parts by weight of a silane coupling agent, A-6) A composition for producing TPU containing 2 to 20 parts by weight of a crosslinking agent is reacted with 0.01 to 1 part by weight of a catalyst to produce the TPU.

[0026] The number average molecular weight of the A-1) polyol may be 2500 g / mol to 4000 g / mol.

[0027] The polyether polyol of the A-1) polyol can be obtained by reacting an alkylene oxide such as ethylene oxide or propylene oxide with a polyhydroxyalkane or an amine compound. As the hydroxyalkane, glycols such as ethylene glycol or propylene glycol, or triols such as glycerol or trimethylolpropane can be used. As the amine compound, ammonia, triethanolamine, ethylenediamine, etc. can be used.

[0028] The polyester polyol (A-1) can be obtained by reacting a dicarboxylic acid with one or more diols. The dicarboxylic acid can include, for example, an aliphatic diacid such as adipic acid, glutaric acid, azelaic acid, or sebacic acid, or an aromatic acid such as phthalic acid, isophthalic acid, terephthalic acid, or naphthenic acid. The diol can include glycols such as ethylene glycol, 1,2-propylene glycol, diethylene glycol, 1,4-butylene glycol, or 1,6-hexylene glycol, or polyhydric alcohols such as glycerol, trimethylolpropane, or pentaerythritol.

[0029] Examples of the A-2) diisocyanate-based compound include toluene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), xylene diisocyanate, hydrogenated diphenylmethane diisocyanate, naphthalene-1,5-diisocyanate (NDI), isophorone diisocyanate (IPDI), cyclohexyl diisocyanate (CHDI), and hexamethylene diisocyanate.

[0030] Examples of A-3) compounds containing hydrogen and an acid functional group capable of reacting with isocyanate include N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, 2,2-bis(hydroxymethyl)butanoic acid, 2,2-bis(hydroxymethyl)pentanoic acid, 2,2-bis(hydroxymethyl)hexanoic acid, 3,5-diamino-4-methylbenzoic acid, 4,4-diamino(1,1-diphenyl)-2,2-disulfonic acid, 4,6-diaminobenzene-1,3-disulfonic acid, 4,4-diamino-2,2-stilbenzenedisulfonic acid, and dihydrolipoic acid.

[0031] In addition, A-3) the compound containing hydrogen and an acid functional group capable of reacting with isocyanate may include a compound neutralized with a neutralizing agent, and the neutralizing agent may be an amine compound, such as butylamine, 3-amino-1,2,4-triazole, (2-methylbutyl)amine, 5-cyclopropyl-1,3,4-oxadiazol-2-amine, dodecylamine, or cyclohexylamine.

[0032] The A-4) hydroxyl group-containing siloxane compound may be hydroxyl group-containing polydimethylsiloxane (PDMS), and the hydroxyl group value may be 20 mg KOH / g to 100 mg KOH / g.

[0033] The A-5) silane coupling agent is a silane coupling agent containing one of an amino group, a mercapto group, and an epoxy group, and may include, for example, r-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, r-glycidoxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, etc., and may suppress the surface migration of siloxane-based compounds.

[0034] Examples of the A-6) crosslinking agent include diethanolamine, 1,4-butylenediamine, 1,6-hexamethylenediamine, triethanolamine, diisopropanolamine, ethylene glycol, butanediol, 1,6-hexanediol, 1,4-cyclohexanediol, low molecular weight alkylene oxides, multifunctional amine or alcohol adducts, and various low molecular weight multifunctional hydroxy or amine compounds. The low molecular weight may mean a weight average molecular weight of 50 to 500.

[0035] The weight average molecular weight of the A) thermoplastic polyurethane may be 80,000 g / mol to 200,000 g / mol.

[0036] When the thermoplastic polyurethane A contains a polyether-based polyol as a main component, it can have better affinity with metal particles and weather resistance.When the thermoplastic polyurethane A contains a polyester-based polyol as a main component, it can have better repeated bending fatigue resistance, and it can further contain a hydrolysis inhibitor described below.

[0037] The thermoplastic polyurethane A) may have a Shore A hardness of 59 to 92, preferably 60 to 90. If the Shore A hardness is less than 59, the molded article to which the composition is applied may be damaged under tension due to insufficient mechanical properties, and the composition may be difficult to maintain its shape during extrusion molding, resulting in reduced productivity. If the Shore A hardness is more than 92, the elasticity and flexibility of the material may be insufficient, resulting in reduced fatigue resistance from repeated bending, difficulty in mixing, requiring an excessive amount of plasticizer, and separation of metal particles in the molded article to which the composition is applied may occur.

[0038] As the thermoplastic polyurethane A, products under the trade names Desmopan 9370A (Covestro), Elastollan 1180A 10 (BASF), Estane 58245 (Lubrizol), etc. may be used.

[0039] The plasticizer (B) may be a liquid or solid substance capable of increasing the flexibility and processability of the composition. The plasticizer may exist in a liquid state at room temperature of 23°C to 25°C.

[0040] The B) plasticizer may include one selected from the group consisting of paraffinic compounds, naphthenic compounds, olefinic compounds, aromatic compounds, and combinations thereof, and may include, for example, naphthenic compounds (oils) and olefinic compounds (oils).

[0041] The vehicle wheel component composition may contain 1 to 30 parts by weight, preferably 7 to 28 parts by weight, of B) plasticizer, based on 100 parts by weight of A) thermoplastic polyurethane. If the plasticizer content is less than 1 part by weight, flexibility may be insufficient, resulting in poor surface shape, and interfacial reactivity between the metal particles and the polymer component may be insufficient, leading to the likelihood of cracks occurring due to repeated bending. If the plasticizer content exceeds 30 parts by weight, migration of the plasticizer to the polymer surface may occur, causing sticking during blending and poor shape during extrusion molding.

[0042] As the plasticizer (B), products such as Shellflex 371 (Shell) and Synfluid 6cSt (Chevron) can be used.

[0043] The C) metal particles may include a metal that is corrosion-resistant and has a high density or specific gravity, and may include, for example, stainless steel, titanium, nickel, chromium, zinc, copper, nickel-copper alloy (Monel), nickel-chromium alloy (Inconel), nickel-molybdenum-chromium alloy (Hastelloy), etc., and preferably may include a material selected from the group consisting of austenitic stainless steel, ferritic stainless steel, martensitic stainless steel, and combinations thereof.

[0044] The C) metal particles may be made of austenitic stainless steel such as SUS304, and may also be made of SUS309, 310, 314, 330, 303, 316, 317, etc., as required.

[0045] The C) metal particles may be made of ferritic stainless steel such as SUS430, and may be made of SUS444, 434, 436, 405, 409, etc., as required.

[0046] The C) metal particles may be made of martensitic stainless steel such as SUS630, or, if necessary, SUS631.

[0047] The C) metal particles may be a mixture of relatively small first particles, medium second particles, and relatively large third particles. The size (D50) of the first particles may be 10 μm to 50 μm, the size (D50) of the second particles may be 30 μm to 120 μm, and the size (D50) of the third particles may be 120 μm to 150 μm. In this specification, D50 may be the particle size corresponding to 50% cumulative weight in the particle size-weight distribution.

[0048] The C) metal particles may include the first particles and the second particles, and the weight ratio of the first particles to the second particles may be 3:7 to 7:3.

[0049] When the C) metal particles include the first particles, second particles, and third particles, 50 to 150 parts by weight of the first particles and 50 to 150 parts by weight of the third particles may be mixed based on 100 parts by weight of the second particles.

[0050] The size (D50) of the C) metal particles may be 1 μm to 150 μm, preferably 30 μm to 120 μm. When the metal particles have such a particle size, they have excellent dispersibility and can be filled into the thermoplastic polyurethane at a high filling rate, which can contribute to ensuring mechanical properties.

[0051] The density of the C) metal particles is 6 g / cm 3 or more, preferably 6.5 g / cm 3 For more details, see 10g / cm 3 The density is a tap density, which may be measured by minimizing porosity using a conventional tap density measuring device. The apparent density of the metal particles is 4 g / cm. 3 ~8g / cm 3 It could be.

[0052] The shape of the metal particles (C) may be any of irregular, plate-like, spherical, etc., but preferably spherical.

[0053] The vehicle wheel component composition may contain 400 to 1680 parts by weight, preferably 600 to 1650 parts by weight, of the C) metal particles, based on 100 parts by weight of thermoplastic polyurethane. If the content of the metal particles is less than 400 parts by weight, a molded product to which the composition is applied may require a larger volume, which may result in noise and noise when applied to a vehicle wheel. If the content of the metal particles is more than 1680 parts by weight, poor mixing may occur during mixing of the composition and preparation of the molded product, separation of the metal particles may occur, and insufficient interfacial reactivity between the metal particles and the thermoplastic polyurethane may result in reduced repeated bending fatigue resistance.

[0054] The vehicle wheel component composition may optionally contain a hydrolysis inhibitor and an antioxidant. Examples of the hydrolysis inhibitor and antioxidant include hydroxycitric structure-containing additives (e.g., Stabaxol I, P200), carbamate bond-containing additives (e.g., Stabaxol P100, Ucarlink XL-29SE), epoxide group-containing additives (e.g., oxazolidine, Loxiol G59), phenol group-containing additives (e.g., Irganox 1010, 1076, 245), phosphate ester group-containing additives (e.g., Irgafox 168, Ultranox 626), hydroxylamine group-containing additives (e.g., Tinuvin 770, 765), and carboimide compounds. The hydrolysis inhibitor may be added in an amount of 0.5 to 5 parts by weight per 100 parts by weight of the thermoplastic polyurethane. By maintaining this weight ratio, the hydrolysis inhibitor can be easily dispersed and its function can be effectively utilized.

[0055] The composition for vehicle wheel components may further include a hydroxyl agent, a vulcanization accelerator, a processing aid, an antioxidant, a filler, etc. The hydroxyl agent may include a metal oxide, a metal hydroxide, etc. The vulcanization accelerator may include a quaternary ammonium salt, a quaternary phosphonium salt, etc. The antioxidant may include a diphenylamine derivative, a phenylenediamine derivative, etc. The processing aid may include stearic acid, zinc oxide, etc. The filler may include carbon black, kaolin clay, talc, algal earth, etc.

[0056] The apparent density of the composition for vehicle wheel components is 3 g / cm 3 More than 8.5g / cm 3 It can be the following:

[0057] The composition for vehicle wheel components can be extruded to produce a molded body, and the molded body can have excellent values ​​for parameters related to bending fatigue resistance, hydrolysis resistance, salt water resistance (corrosion resistance), and weather resistance, which will be described later.

[0058] Molded body A molded article according to one aspect of the present invention may be obtained by extrusion molding the composition for a vehicle wheel component.

[0059] The molded body may have a weight ratio of each component substantially similar to that of the wheel component composition of the vehicle, and may be obtained by extruding the wheel component composition, from which a portion of the plasticizer component has evaporated. Exemplarily, the molded body may include, based on 100 parts by weight of A) thermoplastic polyurethane, 0.5 to 28 parts by weight of B) plasticizer, and 400 to 1680 parts by weight of C) metal particles, and may have a density of 3.2 g / cm. 3 More than 8g / cm 3 The density may be an apparent density.

[0060] The extrusion molding may include heating the composition for a vehicle wheel component to a predetermined temperature, extruding the heated resultant, and post-treating the extruded resultant.

[0061] The heating temperature in the extrusion molding is in the temperature range around the melting point between the glass transition temperature and the melting point of the thermoplastic polyurethane, and may be, for example, a temperature of 130°C to 180°C.

[0062] The extrusion in the extrusion molding can be carried out to form an extrudate having a desired shape.

[0063] The post-processing in the extrusion molding may include a process of cutting the extrudate, a process of printing the surface, and the like.

[0064] The extrusion molding may be performed using an extruder including a hopper into which raw materials flow, a barrel communicating with the hopper and including a fluidization space for the raw materials, a stirring means for stirring and moving the raw materials within the fluidization space, a heater for heating the fluidization space, a discharge die communicating with the fluidization space, etc. Also, a Banbury, kneader, mixing roller, etc. may be used to mix, blend, and disperse the composition for vehicle wheel components prior to extrusion molding.

[0065] The molded article is substantially free from cracks or breaks when subjected to the following bending test 50 times. In this specification, a crack may be a gap or split portion having a width of 50 or more.

[0066] [Bending test] A plate-shaped molded body measuring 23 mm wide, 100 mm long, and 4.5 mm thick was bent along its longitudinal direction for 2 seconds so that one end and the other end were in contact, and then restored to its original state. Here, the longitudinal direction refers to the longer of the horizontal and vertical directions of the molded body.

[0067] The molded article does not substantially crack or break even when the bending test is carried out 70 times or 100 times.

[0068] The molded body does not crack or break after being treated with MS 220-17(4.6) at a temperature of 120° C. and a relative humidity of 100% for 48 hours.

[0069] The molded body is substantially free from corrosion, with a surface corrosion area of ​​0.1% by volume or less after being sprayed with salt water having a temperature of 35°C, a salt water concentration of 5% by weight, and a pH of 7 for 720 hours according to MS 600-35(7.11) and IEC 60068-2-52. The salt water may contain sodium chloride and calcium chloride in the above concentrations.

[0070] The molded article is resistant to UV light of 340 nm at 0.75 W / m according to MS 210-06, SAE J2527, and ASTM D7869. 2 One cycle consisted of 120 minutes of irradiation and 60 minutes of water spraying in the dark, and the UV irradiation dose was 2500kJ / m 2 After processing until the temperature reaches 100°C, discoloration, migration, and whitening do not occur substantially, and the change in the L, a, and b values ​​of the CIE Lab color coordinates measured after UV irradiation under the above conditions can be within 5% compared to before irradiation.

[0071] The molded body can be applied to parts or components that require the above properties, such as vehicle wheel components and wheel balance weights. When applied to wheel balance weights, it can be formed into a long, rollable strip as shown in Figure 1. A separate film can be attached to one and / or the other side of the molded body, and an adhesive film and a release film can also be attached.

[0072] The present invention will be described in detail below with reference to the following examples and comparative examples, but the technical concept of the present invention is not limited thereto.

[0073] Example 1 A composition containing 100 parts by weight of A) a thermoplastic polyurethane elastomer based on polyether polyol and having a Shore A hardness of 60, B) 15 parts by weight of naphthenic oil as a plasticizer, and C) 1,415 parts by weight of ferritic stainless steel powder (30-120 μm) as metal particles was blended in a heated mixer and extruded in a heated extruder to produce a molded body. The blending and extrusion were carried out at temperatures of 130-180°C.

[0074] Example 2 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 70 was used, B) 19 parts by weight of plasticizer was used, and C) 1650 parts by weight of metal particles was used.

[0075] Example 3 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 80 was used, B) 25 parts by weight of plasticizer was used, and C) 1,100 parts by weight of metal particles were used.

[0076] Example 4 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 90 was used, B) 28 parts by weight of plasticizer was used, and C) 900 parts by weight of metal particles were used.

[0077] Example 5 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 70 was used, B) 7 parts by weight of plasticizer was used, and C) 600 parts by weight of metal particles were used.

[0078] Example 6 In Example 1, A) a thermoplastic polyurethane elastomer in which a polyether polyol-based polyurethane elastomer and a polyester polyol-based polyurethane elastomer were mixed in a weight ratio of 5:5 and had a Shore A hardness of 70 was used, and C) 1500 parts by weight of metal particles and 1 part by weight of a hydrolysis inhibitor were used. The remaining conditions were the same as in Example 1, and a molded body was manufactured.

[0079] Comparative Example 1 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 58 was used, B) 13 parts by weight of plasticizer was used, and C) 1,380 parts by weight of metal particles were used.

[0080] Comparative Example 2 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 93 was used, B) 35 parts by weight of plasticizer was used, and C) 850 parts by weight of metal particles was used.

[0081] Comparative Example 3 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 70 was used, B) 28 parts by weight of plasticizer was used, and C) 1700 parts by weight of metal particles were used.

[0082] Comparative Example 4 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 70 was used, B) the plasticizer was omitted, and C) 1,300 parts by weight of metal particles was used.

[0083] Comparative Example 5 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 70 was used, B) the plasticizer was omitted, and C) 380 parts by weight of metal particles was used.

[0084] Reference example 6 A molded article was manufactured under the same conditions as in Example 1, except that A) a polyester-based polyurethane elastomer with a Shore A hardness of 70 was used as the thermoplastic polyurethane elastomer, B) 7 parts by weight of plasticizer was used, and C) 600 parts by weight of metal particles were used. No separate hydrolysis inhibitor was added to the raw materials.

[0085] Comparative Example 7 A molded body was manufactured under the same conditions as in Example 1, except that A) a thermoplastic polyurethane elastomer having a Shore A hardness of 70 was used, B) 35 parts by weight of plasticizer was used, and C) 1700 parts by weight of metal particles was used.

[0086] The conditions for the above Examples, Comparative Examples and Reference Examples are summarized in Table 1. [Table 1] TPU: Thermoplastic polyurethane elastomer

[0087] Experimental example - Bending fatigue resistance and density (specific gravity) measurement The bending fatigue resistance of the molded articles prepared in the above Examples, Comparative Examples, and Reference Examples was measured by the following bending test as shown in FIG. 2, and the apparent density (23°C) was measured using a density meter. The results are shown in Table 2 and FIG. 3.

[0088] [Bending test] A plate-shaped molded body measuring 23 mm wide, 100 mm long, and 4.5 mm thick is bent in the longitudinal direction so that one end and the other end are in contact at a temperature of 23°C and a relative humidity of 50% for 2 seconds, and then restored to its original state. This process is repeated until cracks appear.

[0089] Experimental example - Hydrolysis resistance measurement The molded articles prepared in the above Examples, Comparative Examples, and Reference Examples were treated with MS 220-17(4.6) at a temperature of 120°C and a relative humidity of 100% for 48 hours, and then the presence or absence of cracks and fractures was measured. The results are shown in Table 2, and some of the results are shown in Figure 4.

[0090] Experimental example - Saltwater resistance measurement The molded articles prepared in the examples, comparative examples, and reference examples were sprayed with salt water at 35°C, 5 wt% salt concentration, and pH 7 for 720 hours in accordance with MS 600-35(7.11) and IEC 60068-2-52, and the state of surface corrosion was measured. The results are shown in Table 2.

[0091] Experimental example - Weather resistance measurement The molded articles produced in the above Examples, Comparative Examples and Reference Examples were irradiated with 340 nm ultraviolet light at 0.75 W / m according to MS 210-06 and SAE J2527. 2 One cycle consisted of 120 minutes of irradiation with UV light and 60 minutes of water spraying in the dark, with an ultraviolet irradiation dose of 2500kJ / m 2 After processing until the temperature reached 100°C, discoloration, migration and whitening were measured. The results are shown in Table 2.

[0092] [Table 2]

[0093] With reference to this, it was confirmed that Examples 1 to 6 had good composition compoundability and extrusion appearance of the molded body, and that bending fatigue resistance, density, hydrolysis resistance, salt water resistance, and weather resistance all met appropriate levels.

[0094] Comparative Example 1 used TPU with a slightly low Shore A hardness value, and cracks occurred after 40 repetitions of the bending test due to insufficient mechanical properties.

[0095] Comparative Example 2 used a TPU with a somewhat high Shore A hardness, which resulted in poor mixability and flexibility, resulting in fine cracks occurring at the edges during extrusion molding and poor appearance.

[0096] Comparative Example 3 contained an excessive amount of metal particles, which resulted in poor mixing and separation of the metal particles. Also, the interfacial reactivity between the metal particles and TPU was insufficient, resulting in cracks after 40 repetitions of the bending test.

[0097] In Comparative Example 4, no plasticizer was used, and therefore the interfacial reactivity between the metal particles and the TPU was insufficient, resulting in cracks occurring after 45 repetitions of the bending test.

[0098] In Comparative Example 5, the density (specific gravity) value of the molded body did not satisfy the requirements for a wheel balance weight product. 2 If it is less than this, the volume will be relatively large for the specific weight required, which may cause clunks and noise in the wheel.

[0099] In Reference Example 6, a TPU based on polyester polyol was used, and no hydrolysis inhibitor was added. Therefore, cracks and crumbles occurred during the hydrolysis resistance measurement, and discoloration occurred due to surface blooming during the weather resistance evaluation.

[0100] In Comparative Example 7, an excessive amount of plasticizer was added, and during mixing, a sticky substance was generated in the mixer, and the plasticizer migrated, causing discoloration during the weather resistance evaluation.

[0101] Although the embodiments of the present invention have been described above, it will be understood by those skilled in the art that the present invention can be embodied in other specific forms without changing the technical concept or essential features of the present invention. Therefore, it should be understood that the embodiments described above are illustrative in all respects and are not limiting.

Claims

1. Based on 100 parts by weight of thermoplastic polyurethane, 1 to 30 parts by weight of a plasticizer; 400 to 1680 parts by weight of metal particles, Density is 3 g / cm ３ That's all, The thermoplastic polyurethane has a Shore A hardness of 59 to 92.

2. The composition for a vehicle wheel component according to claim 1 , wherein the wheel component is a wheel balance weight.

3. 7 to 28 parts by weight of the plasticizer; 600 to 1650 parts by weight of the metal particles, 2. The composition for a vehicle wheel component according to claim 1, wherein the thermoplastic polyurethane has a Shore A hardness of 60 to 90.

4. the thermoplastic polyurethane comprises a thermoplastic polyurethane elastomer; 2. The composition for a vehicle wheel component according to claim 1, wherein the thermoplastic polyurethane elastomer is obtained by reacting one polyol selected from the group consisting of polyester polyol, polyether polyol, and a combination thereof, a diisocyanate-based compound, a compound containing hydrogen and an acid functional group capable of reacting with isocyanate, a hydroxyl group-containing siloxane-based compound, a silane coupling agent, and a crosslinking agent.

5. The vehicle wheel component composition according to claim 4 , wherein when the thermoplastic polyurethane elastomer contains a component derived from a polyester polyol, the vehicle wheel component composition further contains a hydrolysis inhibitor.

6. 2. The vehicle wheel component composition according to claim 1, wherein the thermoplastic polyurethane has a weight average molecular weight of 80,000 g / mol to 200,000 g / mol.

7. The vehicle wheel component composition according to claim 1 , wherein the plasticizer is selected from the group consisting of paraffinic compounds, naphthenic compounds, olefinic compounds, aromatic compounds, and combinations thereof.

8. The density of the metal particles is 6 g / cm ３ The composition for a vehicle wheel member according to claim 1 , wherein the composition is as described above.

9. The vehicle wheel component composition of claim 1 , wherein the metal particles are selected from the group consisting of austenitic stainless steel, ferritic stainless steel, martensitic stainless steel, and combinations thereof.

10. The composition for vehicle wheel components according to claim 1, wherein the size (D50) of the metal particles is 1 μm to 150 μm.

11. the metal particles include first particles, second particles, and third particles; The size (D50) of the first particles is 10 μm to 50 μm, The size (D50) of the second particles is 30 μm to 120 μm, The composition for a vehicle wheel component according to claim 1, wherein the size (D50) of the third particles is 120 μm to 150 μm.

12. The vehicle wheel component composition according to claim 1, further comprising a hydroxyl agent, a vulcanization accelerator, a processing aid, an antioxidant and a filler.

13. Based on 100 parts by weight of thermoplastic polyurethane, 400 to 1680 parts by weight of metal particles; a plasticizer, Density is 3.2 g / cm ３ That's all, The thermoplastic polyurethane has a Shore A hardness of 59 to 92.

14. The molded article according to claim 13, which does not crack or break when the following bending test is carried out 50 times. [Bending test] A plate-shaped molded body measuring 23 mm wide, 100 mm long, and 4.5 mm thick is bent in the longitudinal direction so that one end and the other end are in contact at a temperature of 23°C and a relative humidity of 50% for 2 seconds, and then allowed to return to its original state.

15. 14. The molded article according to claim 13, which does not crack or break after being treated at a temperature of 120°C and a relative humidity of 100% for 48 hours.

16. A wheel balance weight comprising the molded article of claim 13.

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