Thermoplastic flame retardant resin composition and molded article

Abstract

The present invention relates to a thermoplastic flame retardant resin composition and / or a molded article. According to the present invention, the present invention has the effects of: providing a thermoplastic flame-retardant resin composition which has excellent post-molding shrinkage resistance and processability required in a large-area lightweight molded article having a very thin thickness, exhibits high flame retardancy, and has light weight; and a molded article manufactured using the thermoplastic flame retardant resin composition.

Description

Technical Field

[0001] [Cross-references to related applications]

[0002] This application claims priority to Korean Patent Application No. 10-2024-0087977, filed on July 4, 2024, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

[0003] This invention relates to a thermoplastic flame-retardant resin composition and a molding article. More specifically, this invention relates to: a lightweight thermoplastic flame-retardant resin composition having excellent post-molding shrinkage resistance and processability, as well as high flame retardancy, required in large-area lightweight molding articles with very thin thickness; and a molding article manufactured using the thermoplastic flame-retardant resin composition. Background Technology

[0004] Polypropylene resin is a general-purpose plastic, widely used in various fields such as automotive, building materials, and electrical components due to its excellent processing characteristics, chemical resistance, weather resistance, and high flexibility, in the form of injection-molded products, sheets, and blow-molded products. Recently, high-gloss grades with excellent surface gloss and abrasion resistance; heavy-weight grades with improved rigidity and damping properties; heat-resistant grades with thermal stability; high-strength grades that meet various mechanical property requirements by incorporating glass fibers and exhibit tensile strength approximately 200-300% higher and flexural modulus greater than 4 times that of ordinary polypropylene resin; high-impact grades that improve impact strength through the use of RTPO (reactor-produced thermoplastic olefins) and synthetic rubber and exhibit excellent impact strength and flowability at low temperatures; and long-term weather-resistant grades with excellent weather resistance and no discoloration even after prolonged outdoor exposure. With the trend towards increasing complexity and functionalization, various new applications are being explored.

[0005] Initially, polypropylene resin was included in the category of flammable plastics, thus limiting its use as a flame retardant. However, as polypropylene resin has become more functionalized and its applications have expanded, its function as a flame-retardant material has also become necessary. To meet these needs, flame-retardant grades of polypropylene with excellent flame retardancy have been developed and used by incorporating various organic or inorganic flame retardants.

[0006] This flame-retardant polypropylene is primarily used in electrical and electronic components included in televisions, monitors, and air conditioners. Recently, in addition to flame retardancy, these products have been required to possess properties such as moldability, processability, and lightweight. For example, insulating sheets for energy storage systems exhibiting a UL94 flame retardancy rating of V-0 have a very thin thickness of less than 0.3 mm, large surface area, excellent post-molding shrinkage resistance, high flame retardancy and processability, and a lightweight composition of less than 1.

[0007] Generally, the flame retardancy of polypropylene resin tends to be inversely proportional to its lightweight, so resin compositions with high flame retardancy tend to have a higher specific gravity.

[0008] Previously, as a flame-retardant polypropylene resin, Japanese Patent Application Publication No. Hei 6-184372 disclosed a material obtained by mixing flame retardants such as tetrabromobisphenol A or tetrabromobisphenol S with polypropylene. This flame-retardant polypropylene resin can increase its flame-retardant effect by mixing in a small amount of flame retardant; however, due to its poor processing properties, it is difficult to form large-area, very thin products.

[0009] To improve the aforementioned processing performance defects, Japanese Patent Application Publication No. Hei 9-52988 discloses a method in which tetrabromobisphenol A or tetrabromobisphenol S compound is added as a flame retardant and mixed with chlorinated polyethylene. However, the product has a problem of having relatively low flame retardancy corresponding to the UL94 V-2 rating.

[0010] Furthermore, according to Japanese Patent Application Publication No. 2000-344973 and Japanese Patent Application Publication No. 2001-220470, a thermoplastic flame-retardant resin composition obtained by adding halogenated diphenyl ether compounds such as decabromodiphenyl ether and octabromodiphenyl ether and halogenated bisphenol compounds such as hexabromocyclododecane as flame retardants exhibits high flame retardancy (UL94V-2 to V-0), but has problems in terms of mechanical properties, heat resistance and weather resistance. Summary of the Invention

[0011] Technical issues

[0012] Therefore, the present invention was made in view of the above problems. One object of the present invention is to provide a thermoplastic flame retardant resin composition that has excellent post-molding shrinkage resistance and processability required in large-area lightweight molded articles with very thin thickness, exhibits high flame retardancy and is lightweight.

[0013] Another object of the present invention is to provide a molded article manufactured using the thermoplastic flame-retardant resin composition.

[0014] The above and other objectives can be achieved by the invention described below.

[0015] Technical solution

[0016] I) According to one aspect of the present invention, a thermoplastic flame-retardant resin composition is provided, comprising a resin represented by the following chemical formula 1; a resin represented by the following chemical formula 2; a post-molding shrinkage inhibitor represented by the following chemical formula 3; a halogenated flame retardant; and a flame-retardant additive, wherein the resin represented by chemical formula 2 and the resin represented by chemical formula 1 are contained in a weight ratio of 1:6 to 1:7.4, the resin represented by chemical formula 1 comprising a first resin and a second resin in a weight ratio of 1:1 to 1:3.8, wherein in the first resin, n is an integer between 1000 and 3000, and in the second resin, n is an integer between 3000 and 6000.

[0017] [Chemical Formula 1]

[0018]

[0019] [Chemical Formula 2]

[0020]

[0021] [Chemical Formula 3]

[0022]

[0023] In chemical formulas 1 and 2, n is an integer between 1000 and 6000, and m is an integer between 2000 and 8000; in chemical formula 3, the carbon (C) symbol and the carbon-hydrogen bond symbol are omitted.

[0024] II) According to I), the first resin may have a melt index of 5 g / 10 min to 50 g / 10 min, as measured by ISO 1133 standard at 230 °C under a load of 2.16 kg.

[0025] III) According to I) to II), the second resin may have a melt index of 0.01 g / 10 min to 4 g / 10 min, as measured by ISO 1133 standard at 230 °C under a load of 2.16 kg.

[0026] IV) According to I) to III), the resin represented by chemical formula 2 and the post-molding shrinkage inhibitor represented by chemical formula 3 may be contained in a weight ratio of 1:0.5 to 1:1.5.

[0027] V) According to I) to IV), halogenated flame retardants can be brominated flame retardants.

[0028] VI) According to I) to V), brominated flame retardants may include one or more selected from tetrabromobisphenol A, decabromodiphenyl ether, octabromo-1,3,3-trimethyl-1-phenylindanium, tetrabromobisphenol A-bis(2,3-dibromopropyl ether), and 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine.

[0029] VII) According to I) to VI), flame retardant additives may be antimony compounds.

[0030] VIII) According to I) to VII), antimony compounds may include one or more selected from antimony trioxide, polysiloxane compounds, biotite, muscovite, iron oxide, tungsten oxide and calcium carbonate.

[0031] IX) According to another aspect of the invention, a thermoplastic flame-retardant resin composition is provided, comprising 19% to 29% by weight of a first resin represented by the following chemical formula 1, wherein n is an integer between 1000 and 3000, wherein the first resin has a melt index of 5 g / 10 min to 50 g / 10 min as measured by ISO 1133 standard at 230°C under a load of 2.16 kg; and 40% to 50% by weight of a second resin represented by the following chemical formula 1, wherein n is between 3000 and 600. The second resin has a melt index of 0.01 g / 10 min to 4 g / 10 min, measured according to ISO 1133 standard at 230°C under a load of 2.16 kg; 6 wt% to 14 wt% of a resin represented by the following chemical formula 2, where m is an integer between 2000 and 8000; 6 wt% to 14 wt% of a post-molding shrinkage inhibitor represented by the following chemical formula 3; 6.5 wt% to 11 wt% of a brominated flame retardant; and 1 wt% to 4 wt% of an antimony flame retardant additive.

[0032] It contains resin represented by chemical formula 2 and resin represented by chemical formula 1 in a weight ratio of 1:6 to 1:7.4.

[0033] [Chemical Formula 1]

[0034]

[0035] [Chemical Formula 2]

[0036]

[0037] [Chemical Formula 3]

[0038]

[0039] In chemical formulas 1 and 2, n is an integer between 1000 and 6000, and m is an integer between 2000 and 8000; in chemical formula 3, the carbon (C) symbol and the carbon-hydrogen bond symbol are omitted.

[0040] X) According to another aspect of the present invention, a molding article manufactured using the above-described thermoplastic flame-retardant resin composition is provided.

[0041] XI) According to X), the molded article can be an energy storage system component or a large-area sheet with a thickness of less than 0.3 mm.

[0042] Beneficial effects

[0043] The thermoplastic flame-retardant resin composition according to the present invention exhibits excellent flammability in the UL94 vertical burning test and demonstrates a V-0 flame retardancy rating. Furthermore, the thermoplastic flame-retardant resin composition according to the present invention possesses excellent post-molding shrinkage resistance and processability, thus making it suitable for large-area, lightweight molded articles requiring such properties.

[0044] Therefore, the thermoplastic flame-retardant resin composition and / or molding article according to the present invention can be applied to various industrial fields, such as electrical and electronic products and automotive parts that require thermoplastic flame-retardant resin compositions and / or molding articles. Attached Figure Description

[0045] Figure 1 The figure includes a graph confirming the test results of the shrinkage resistance of the molded article manufactured according to the present invention after molding. Detailed Implementation

[0046] The invention is described in more detail below.

[0047] For example, in this invention, the halogen can be at least one of fluorine (F), chlorine (Cl), bromine (Br) and iodine (I), preferably at least one of chlorine and bromine, more preferably bromine.

[0048] The thermoplastic flame-retardant resin composition according to the present invention comprises two or more different polyolefin resins, a post-molding shrinkage inhibitor, a halogenated flame retardant, and a flame-retardant additive.

[0049] The inventors have demonstrated that, when preparing the thermoplastic flame-retardant resin composition of the present invention, by subjecting two or more different polyolefin resins to a predetermined molding process and mixing them with appropriate amounts of shrinkage inhibitors, halogenated flame retardants, and flame-retardant additives, the problem of post-molding shrinkage of very thin, large-area molded articles with a thickness of less than 0.3 mm is solved without reducing the flame retardancy produced by the flame retardants and flame-retardant additives contained in the thermoplastic flame-retardant resin composition. Furthermore, the required physical properties and reliability of the molded articles are provided. Based on these results, the inventors conducted further research to complete the present invention.

[0050] The components constituting the thermoplastic flame retardant resin composition are described in more detail below.

[0051] Resin represented by chemical formula 1

[0052] The resin represented by chemical formula 1 according to the present invention may have the following structure.

[0053] [Chemical Formula 1]

[0054]

[0055] In chemical formula 1, n is an integer between 1000 and 6000.

[0056] When supplied as a flame-retardant resin composition, the resin represented by chemical formula 1 can provide excellent flame retardancy without increasing the specific gravity.

[0057] Within the scope defined by this invention, the resin represented by chemical formula 1 can be prepared by methods commonly used in the technical field to which this invention pertains, or commercially available products can be used, without particular limitation.

[0058] For example, a resin represented by chemical formula 1 may include one or more of a first resin in which n is an integer between 1000 and 3000 and a second resin in which n is an integer between 3000 and 6000.

[0059] For example, the first resin may have a melt index of 5 g / 10 min to 50 g / 10 min, preferably 5 g / 10 min to 30 g / 10 min, and more preferably 5 g / 10 min to 20 g / 10 min, as measured by ISO 1133 standard at 230°C and under a load of 2.16 kg. In this case, the effect of suppressing the strong pressure increase that may occur during extrusion processing can be provided by providing appropriate flowability.

[0060] For example, based on a total of 100% by weight of a thermoplastic flame-retardant resin composition comprising the first resin, the first resin may be included in an amount of 19% by weight or more, specifically 19% to 29% by weight, and more preferably 20% to 28% by weight. In this case, the effect of suppressing the strong pressure increase that may occur during extrusion processing can be provided by providing suitable flowability.

[0061] Within the scope defined by this invention, the first resin can be prepared by methods commonly used in the technical field to which this invention pertains, or a commercially available product can be used, without particular limitation.

[0062] For example, the second resin may have a melt index of 0.01 g / 10 min to 4 g / 10 min, preferably 0.01 g / 10 min to 3 g / 10 min, more preferably 0.1 g / 10 min to 3 g / 10 min, as measured by ISO 1133 standard at 230°C under a load of 2.16 kg. In this case, sheets can be produced by extrusion.

[0063] For example, based on a total of 100% by weight of a thermoplastic flame-retardant resin composition containing a second resin, the second resin may be contained in an amount of 50% by weight or less, specifically 40% to 50% by weight, and more preferably 42% to 48% by weight. In this case, sheets can be produced by extrusion.

[0064] Within the scope defined by this invention, the second resin can be prepared by methods commonly used in the technical field to which this invention pertains, or commercially available products can be used, without particular limitation.

[0065] For example, a thermoplastic flame-retardant resin composition comprising a first resin wherein n is an integer between 1000 and 3000 and a second resin wherein n is an integer between 3000 and 6000, based on a total of 100% by weight, wherein the total amount of the first resin and the second resin may be 50% or more, 55% to 74% by weight as a specific example, and more preferably 60% to 74% by weight. In this case, suitable insulation properties and chemical resistance can be provided.

[0066] As a specific example, a first resin and a second resin may be included in a weight ratio of 1:1 to 1:3.8 (first:second), preferably 1:1 to 1:3.4 (first:second), and more preferably 1:1 to 1:3 (first:second), wherein n is an integer between 1000 and 3000, and n is an integer between 3000 and 6000. In this case, the most suitable flowability and viscosity can be provided to produce sheets of less than 0.5 mm by continuous extrusion processing.

[0067] Resin represented by chemical formula 2

[0068] The resin represented by chemical formula 2 according to the present invention can have the following structure.

[0069] [Chemical Formula 2]

[0070]

[0071] In chemical formula 2, m is an integer between 2000 and 8000.

[0072] The resin represented by chemical formula 2 can be further improved in terms of anti-shrinkage effect by using an anti-shrinkage agent represented by chemical formula 3 as described below, without increasing the proportion of the flame-retardant resin composition achieved by the resin represented by chemical formula 1, and without adversely affecting its flame retardancy.

[0073] For example, the resin represented by Formula 2 can have a melt index of 0.1 g / 10 min to 20 g / 10 min, preferably 0.1 g / 10 min to 10 g / 10 min, and more preferably 0.1 g / 10 min to 5 g / 10 min, as measured by ISO 1133 standard at 190°C under a load of 2.16 kg. In this case, the anti-shrinkage effect can be further improved by using a shrinkage inhibitor represented by Formula 3, as described below.

[0074] For example, a resin represented by chemical formula 2 can have a strength of 2 kJ / m³ measured under notched conditions at 23°C according to ISO 180 standards. 2 Up to 20kJ / m 2 Optimal 4kJ / m 2 Up to 15kJ / m 2 More preferably 4kJ / m 2 Up to 10 kJ / m 2 Impact strength. In this case, the impact strength and stiffness of the thermoplastic flame-retardant resin composition can be improved.

[0075] For example, a thermoplastic flame-retardant resin composition comprising a resin represented by chemical formula 2 in a total of 100% by weight may contain a resin represented by chemical formula 2 in an amount of 14% by weight or less, specifically 6% to 14% by weight, and more preferably 6% to 12% by weight. In this case, impact strength or rigidity can be provided without increasing the proportion of the flame-retardant resin composition or adversely affecting its flame retardancy.

[0076] Within the scope defined by this invention, the resin represented by chemical formula 2 can be prepared by methods commonly used in the technical field to which this invention pertains, or commercially available products can be used, without particular limitation.

[0077] In this specification, n and m can be calculated by dividing the number-average molecular weight by the molar mass of each unit, and the number-average molecular weight can be measured as a relative value to a standard polystyrene sample by gel permeation chromatography (GPC), but is not limited thereto.

[0078] Post-molding shrinkage inhibitor

[0079] As a post-molding shrinkage inhibitor according to the present invention, a compound represented by chemical formula 3 may be used.

[0080] [Chemical Formula 3]

[0081]

[0082] The compound represented by Formula 3 contains a propylene moiety, an ethylene moiety, and a crosslinking moiety, thereby improving the compatibility between the resin represented by Formula 1, the resin represented by Formula 2, and the flame retardant and flame retardant additives described below, thus providing improved shrinkage resistance even when molded into a large area at a very thin thickness of less than 0.3 mm.

[0083] In chemical formula 3, the carbon (C) symbol and the carbon-hydrogen bond symbol are omitted.

[0084] For example, a thermoplastic flame-retardant resin composition comprising a resin represented by chemical formula 3 in a total of 100% by weight may contain the resin represented by chemical formula 3 in an amount of 14% by weight or less, specifically 6% to 14% by weight, and more preferably 6% to 12% by weight. In this case, by simultaneously including the propylene portion, the ethylene portion, and the crosslinking portion, the compatibility between the resin represented by chemical formula 1, the resin represented by chemical formula 2, and the flame retardant and flame retardant additives described later can be improved, thereby providing an effect of improved shrinkage resistance after molding even when molded into a large area with a very thin thickness of 0.3 mm or less.

[0085] Within the scope defined by this invention, the resin represented by chemical formula 3 can be prepared by methods commonly used in the technical field to which this invention pertains, or commercially available products can be used, without particular limitation.

[0086] Halogenated flame retardants

[0087] The halogenated flame retardants according to the present invention have better thermal stability than non-halogenated flame retardants.

[0088] For example, halogenated flame retardants can be brominated flame retardants. In this case, the effect of suppressing combustion can be provided by suppressing the spread of the spark after ignition.

[0089] As a specific example, brominated flame retardants may include one or more selected from tetrabromobisphenol A, decabromodiphenyl ether, octabromo-1,3,3-trimethyl-1-phenylindanium, tetrabromobisphenol A-bis(2,3-dibromopropyl ether), and 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine.

[0090] For example, based on a total of 100% by weight of a thermoplastic flame-retardant resin composition containing a halogenated flame retardant, the halogenated flame retardant may be contained in an amount of 11% by weight or less, specifically 6.5% by weight to 11% by weight, and more preferably 6.5% by weight to 10% by weight. In this case, excellent flame retardancy and flowability can be imparted to the thermoplastic flame-retardant resin composition without degrading other properties.

[0091] Within the scope defined by this invention, halogenated flame retardants can be prepared by methods commonly used in the technical field to which this invention pertains, or commercially available products can be used, without particular limitation.

[0092] Flame retardant additives

[0093] The flame retardant additives according to the present invention have the advantage of increasing the flame retardancy provided by the above-mentioned flame retardants without degrading other properties.

[0094] For example, flame retardant additives can be antimony compounds. In this case, they can provide additional effects to further enhance the flame retardant effect.

[0095] As a specific example, flame retardant additives may include one or more selected from antimony trioxide, polysiloxane compounds, biotite, muscovite, iron oxide, tungsten oxide, and calcium carbonate, with antimony trioxide being preferred.

[0096] For example, based on a total of 100% by weight of a thermoplastic flame-retardant resin composition containing flame-retardant additives, the flame-retardant additives may be included in an amount of 4% by weight or less, specifically 1% to 4% by weight, and more preferably 2% to 4% by weight. In this case, excellent flame retardancy and flowability can be imparted to the thermoplastic flame-retardant resin composition without deteriorating other properties.

[0097] Within the scope defined by this invention, flame retardant additives can be prepared by methods commonly used in the technical field to which this invention pertains, or commercially available products can be used, without particular limitation.

[0098] Thermoplastic flame retardant resin composition

[0099] For example, the thermoplastic flame-retardant resin composition according to the invention may contain a resin represented by chemical formula 2 and a post-molding shrinkage inhibitor represented by chemical formula 3 in a weight ratio of 1:0.5 to 1:1.5 (Formula 2: Formula 3), or, as a specific example, 1:0.8 to 1:1.3 (Formula 2: Formula 3). In this case, the tendency for post-molding shrinkage can be effectively suppressed, and economic efficiency can be improved.

[0100] Without affecting appearance performance, the thermoplastic flame retardant resin composition may contain one or more other additives selected from activators, light stabilizers and release agents.

[0101] For example, based on 100 parts by weight of the thermoplastic flame-retardant resin composition, other additives may be included in amounts of 0.1 to 10 parts by weight, preferably 0.1 to 5 parts by weight, and more preferably 0.5 to 2 parts by weight. Within this range, the functions of the other additives can be achieved without deteriorating the inherent properties of the thermoplastic flame-retardant resin composition of the present invention.

[0102] For example, the lubricant may include, but is not limited to, one or more selected from ethylene bis-stearamide, polyethylene oxide wax, magnesium stearate, calcium stearamide and stearic acid.

[0103] For example, HALS-type light stabilizers, benzophenone-type light stabilizers, or benzotriazole-type light stabilizers can be used as light stabilizers, but are not limited to these.

[0104] For example, the release agent may be selected from glyceryl monostearate, glyceryl tristearate, and polyethylene tetrastearate, but is not limited to these.

[0105] Furthermore, the thermoplastic flame-retardant resin composition according to the invention comprises 19% to 29% by weight of a first resin represented by the following chemical formula 1, wherein n is an integer between 1000 and 3000, wherein the first resin has a melt index of 5 g / 10 min to 50 g / 10 min measured at 230°C under a load of 2.16 kg according to ISO 1133 standards; and 40% to 50% by weight of a second resin represented by the following chemical formula 1, wherein n is an integer between 3000 and 6000, wherein the second resin has a melt index of 5 g / 10 min to 50 g / 10 min measured at 230°C according to ISO 1133 standards. Melt index of 0.01 g / 10 min to 4 g / 10 min measured under a load of 2.16 kg; 6 wt% to 14 wt% of resin represented by the following chemical formula 2, wherein m is an integer between 2000 and 8000; 6 wt% to 14 wt% of post-molding shrinkage inhibitor represented by the following chemical formula 3; 6.5 wt% to 11 wt% of brominated flame retardant; and 1 wt% to 4 wt% of antimony flame retardant additive, wherein the resin represented by chemical formula 2 and the resin represented by chemical formula 1 are contained in a weight ratio of 1:6 to 1:7.4 (Formula 2:Formula 1).

[0106] [Chemical Formula 1]

[0107]

[0108] [Chemical Formula 2]

[0109]

[0110] [Chemical Formula 3]

[0111]

[0112] In chemical formulas 1 and 2, n is an integer between 1000 and 6000, and m is an integer between 2000 and 8000. In chemical formula 3, the carbon (C) symbol and the carbon-hydrogen bond symbol are omitted.

[0113] The thermoplastic flame-retardant resin composition exhibits a V-0 flame retardancy rating in the UL94 vertical burning test and demonstrates excellent post-molding shrinkage resistance and processability. Therefore, the thermoplastic flame-retardant resin composition is suitable for large-area, lightweight molded articles requiring such properties, even with very thin surfaces.

[0114] A method for preparing a thermoplastic flame-retardant resin composition will be described. When describing the method for preparing the thermoplastic flame-retardant resin composition of the present invention, all contents of the above-described thermoplastic flame-retardant resin composition are included.

[0115] For example, a method for preparing the thermoplastic flame-retardant resin composition of the present invention includes the following steps: feeding a resin represented by the following chemical formula 1; a resin represented by the following chemical formula 2; a post-molding shrinkage inhibitor represented by the following chemical formula 3; a halogenated flame retardant; and a flame retardant additive into a twin-screw extruder, and performing melt kneading and extrusion.

[0116] [Chemical Formula 1]

[0117]

[0118] [Chemical Formula 2]

[0119]

[0120] [Chemical Formula 3]

[0121]

[0122] In chemical formulas 1 and 2, n is an integer between 1000 and 6000, and m is an integer between 2000 and 8000. In chemical formula 3, the carbon (C) symbol and the carbon-hydrogen bond symbol are omitted.

[0123] It may contain the resin represented by chemical formula 2 and the resin represented by chemical formula 1 in a weight ratio of 1:6 to 1:7.4 (Formula 2: Formula 1).

[0124] For example, the other additives mentioned above may be included in the melt kneading step.

[0125] For example, one or more selected from single-screw extruders, twin-screw extruders, and Banbury mixers, preferably twin-screw extruders, can be used for the melt kneading and extrusion steps. The melt kneading and extrusion steps can be performed by uniformly mixing the composition using a twin-screw extruder and extruding it to obtain a granular thermoplastic flame-retardant resin composition. In this case, product reliability, flame retardancy, and post-molding shrinkage resistance can be improved, resulting in excellent appearance quality.

[0126] For example, kneading and extrusion can be carried out at barrel temperatures of 250°C to 310°C, preferably 260°C to 300°C, more preferably 270°C to 290°C, and even more preferably 250°C to 280°C. In this case, the output per unit time can be increased, and sufficient melt kneading can be achieved. In addition, thermal decomposition of the resin components can be prevented.

[0127] For example, kneading and extrusion can be performed at screw speeds of 100 rpm to 600 rpm, preferably 150 rpm to 400 rpm, more preferably 100 rpm to 350 rpm, even more preferably 150 rpm to 320 rpm, and even more preferably 200 rpm to 310 rpm. Within this range, the output per unit time can be increased, and process efficiency can be improved. Furthermore, excessive cutting of the inorganic filler can be prevented, thereby further improving the rigidity of the final product.

[0128] The thermoplastic flame-retardant resin composition obtained by kneading and extrusion can preferably be provided in granular form.

[0129] There are no particular restrictions on the type of extruder, and extruders commonly used in the art can be appropriately selected and used. For example, a single-screw extruder equipped with one screw or a multi-screw extruder equipped with multiple screws can be used. Considering the uniform kneading of materials, ease of processing, and economic efficiency, a twin-screw extruder equipped with two screws is preferred.

[0130] An extruder includes a feeder for feeding material into the barrel, a screw for conveying and kneading the feed material, and a die for extruding the kneaded material. In this case, the screw consists of multiple screw elements for various functions.

[0131] One or more feeders may be provided. Optionally, two or more feeders may be provided. For example, a main feeder and optional auxiliary feeders may be provided. Optionally, more than two auxiliary feeders may be provided.

[0132] The kneading block of the present invention corresponds to a screw element. Specifically, each kneading block consists of a plurality of discs, preferably 3 to 7 discs, 5 to 7 discs, 3 to 5 discs, or 4 to 5 discs, and has a polygonal or elliptical cross-section. The kneading blocks are arranged continuously in the direction of material conveying. Furthermore, in the kneading block, the phase angle of the discs (indicating the travel angle between the discs) is preferably 45° to 90°.

[0133] Additionally, the kneading blocks include forward kneading blocks capable of conveying, dispensing, and mixing materials; neutral kneading blocks capable of dispensing and mixing materials without conveying materials; and reverse kneading blocks capable of conveying materials in the opposite direction to the conveying direction.

[0134] Molded products

[0135] For example, the molded articles of the present invention include the thermoplastic flame-retardant resin composition of the present invention. In this case, compared with conventional thermoplastic flame-retardant resin compositions, a balance of physical properties between post-molding shrinkage resistance, processability and flame retardancy can be achieved even when molding large areas with a very thin thickness of less than 0.3 mm.

[0136] For example, the molded articles of the present invention can be manufactured by molding the thermoplastic flame-retardant resin composition of the present invention. When describing molded articles comprising the thermoplastic flame-retardant resin composition of the present invention, all contents of the above-described thermoplastic flame-retardant resin composition are included.

[0137] The method for manufacturing molded articles according to the present invention includes the step of injection molding or sheet molding an extruded product manufactured by a method for preparing a thermoplastic flame-retardant resin composition. In this case, even when molding a large area with a very thin thickness of less than 0.3 mm, molded articles with anti-shrinkage ability, processability and flame retardancy after molding can be easily manufactured.

[0138] In injection molding or sheet forming, the injection temperature (cylinder temperature) or sheet forming temperature is preferably 200°C to 300°C, more preferably 200°C to 290°C. Within this range, large-area injection-molded products or sheets with a very thin thickness of less than 0.3 mm can be easily manufactured.

[0139] The injection or compression molding speed can preferably be from 10 mm / s to 100 mm / s, more preferably from 10 mm / s to 80 mm / s, and even more preferably from 20 mm / s to 80 mm / s. Within this range, large-area injection-molded products or sheets with a very thin thickness of less than 0.3 mm can be easily manufactured.

[0140] In injection molding or sheet forming, the pressure is preferably from 10 bar to 150 bar, more preferably from 20 bar to 90 bar, and even more preferably from 40 bar to 80 bar. Within this range, large-area injection-molded products or sheets with a very thin thickness of less than 0.3 mm can be easily manufactured.

[0141] In injection molding or sheet forming, the holding pressure is preferably 10 bar to 100 bar, more preferably 20 bar to 80 bar, and even more preferably 30 bar to 60 bar. Within this range, large-area injection-molded products or sheets with a very thin thickness of less than 0.3 mm can be easily manufactured.

[0142] Molded products can be products that require shrinkage resistance, processability and flame retardancy even when molded over a large area with a very thin thickness of less than 0.3 mm.

[0143] The molded parts can be automotive or electrical / electronic components.

[0144] For example, molded parts can be components of energy storage systems.

[0145] For example, molded products can be large-area sheets with a thickness of less than 0.3 mm.

[0146] The molded articles of the present invention can exhibit a V-0 rating of flame retardancy in the UL94 vertical burning test.

[0147] The molded articles of the present invention have excellent anti-shrinkage ability after molding, which prevents post-molding shrinkage even after being stored at room temperature for 5 to 7 days after being molded into large-area sheets with a very thin thickness of less than 0.3 mm.

[0148] In describing the thermoplastic flame-retardant resin composition of the present invention, the method for preparing the thermoplastic flame-retardant resin composition, and the molding article thereof, it should be noted that other conditions or equipment not explicitly described herein may be suitably selected within the scope of ordinary practice in the art, without particular limitation.

[0149] The invention will now be described in more detail with reference to the preferred embodiments described below. However, these embodiments are provided for illustrative purposes only and should not be construed as limiting the scope and concept of the invention. Furthermore, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the concept and scope of the invention, and such changes and modifications are also within the scope of the appended claims.

[0150] [Example]

[0151] The components used in the examples and comparative examples are as follows.

[0152] *Resins represented by chemical formula 1

[0153] - First resin: BX3500 (SK Co.), with a melt index of 10 g / 10 min measured at 230°C under a load of 2.16 kg according to ISO 1133 standard.

[0154] - Second resin: EP332C (POLYMIRAE Co.), with a melt index of 0.35 g / 10 min measured at 230°C under a load of 2.16 kg according to ISO 1133 standard.

[0155] *Resin represented by chemical formula 2 ME1000 (LG Chem.Co.), whose impact strength, measured at 23°C under notched conditions according to ISO 180 standard, is 8.

[0156] *Resins represented by chemical formula 3KEP-070P (KUMHO POLYCHEM Co.) has a Mooney viscosity of 69 MU measured according to ASTM D1646 standard at ML(1+4)@100℃.

[0157] *Brominated flame retardants SR-743N (DAI-ICHIFR Co.)

[0158] Examples 1 to 3 and Comparative Examples 1 to 12

[0159] According to the contents shown in Tables 2 and 3, the components shown in Tables 2 and 3 were fed into a twin-screw extruder (SMCo., T40) and melt-kneaded and extruded at a temperature of 200°C to 250°C and a rotational speed of 250 rpm to obtain granules. Using the granules, square specimens with dimensions of 60 mm × 60 mm × 2 mm were manufactured using an injection molding machine (Engel, 80 tons).

[0160] Twin-screw extruders have two or more inlets, and all components are fed into the main inlet.

[0161] [Experimental Example]

[0162] The performance of the samples manufactured in Examples 1 to 3 and Comparative Examples 1 to 12 was measured using the following methods, and the results are shown in Tables 2 and 3 below. Figure 1 middle.

[0163] *Flame retardancy (for 0.2 mm thick specimens): Refer to Items 1 and 2 below and Table 1 to evaluate the flame retardancy of 1 / 12 inch thick specimens according to the UL94 measurement method (vertical 1.5 mm).

[0164] 1. Wind the sample onto a 13mm diameter rod (mandrel), attach the top of it with tape, and fix the sample with a clamp.

[0165] 2. The burner and test method evaluated the combustion pattern of the products and the extent of flame spread after two 3-second spark contacts on the specimen.

[0166] [Table 1]

[0167]

[0168] *Post-molding shrinkage resistance (dimensional deformation): Using a 0.2mm thick sample, the difference between the dimension measured immediately after molding and the dimension measured after storage at room temperature for 5 to 7 days after molding is expressed as a percentage (%).

[0169] *Mel flow index: Measured according to ISO 1133 standard at 230°C under a load of 10.0 kg.

[0170] *Specific gravity: Measured at 23°C according to ISO 1183 standard.

[0171] [Table 2]

[0172] Category (by weight %) Example 1 Example 2 Example 3 First Resin 24 29 19 Second resin 45 40 50 Resin represented by chemical formula 2 10 10 10 Post-molding shrinkage inhibitor 10 10 10 Bromine flame retardants 8 8 8 Flame retardant additives 3 3 3 Flame retardancy (0.2mm thickness) VTM-0 VTM-0 VTM-0 Post-molding shrinkage resistance (dimensional deformation %) 2.1 1.5 2.2 Melt flow index (g / 10min) 30 33 24 Specific gravity (g / ml) 0.96 0.96 0.96

[0173] [Table 3]

[0174]

[0175]

[0176] As shown in Tables 2 and 3, in the case of the thermoplastic flame retardant resin composition according to the present invention (Examples 1 to 3), compared with the thermoplastic flame retardant resin composition outside the scope of the present invention (Comparative Examples 1 to 12), even when manufacturing a molded article with a very thin thickness of 0.2 mm, the balance of physical properties among the measured items including flame retardancy, post-molding shrinkage resistance, melt flow index and specific gravity is excellent.

[0177] In particular, such as Figure 1 As shown, in the case of Embodiment 1 according to the present invention, excellent anti-shrinkage capability after molding was effectively achieved.

[0178] Conversely, compared to Example 1, in Comparative Example 1, which uses only two types of resin represented by Chemical Formula 1, or in Comparative Example 2, in which a flame retardant and a flame retardant additive are added to the composition of Comparative Example 1, the flame retardancy is poor and post-molding shrinkage occurs.

[0179] Furthermore, in Comparative Example 3, which used two types of resin represented by Chemical Formula 1 and added excessive amounts of flame retardant and flame retardant additives, flame retardancy was ensured. However, compared to Example 1, post-molding shrinkage occurred, and the specific gravity exceeded 1 g / ml, making it impossible to achieve lightweighting.

[0180] In addition, compared with Example 1, Comparative Example 4, which did not add the resin represented by Chemical Formula 2, flame retardant and flame retardant additive, prevented post-molding shrinkage, but did not ensure flame retardancy.

[0181] In addition, in Comparative Example 5, which used two types of resin represented by Chemical Formula 1 and added an excessive amount of post-molding shrinkage inhibitor, similar processing performance to that of Example 1 was achieved, but the flame retardancy was poor.

[0182] Furthermore, compared to Example 1, Comparative Example 6, which did not contain post-molding shrinkage inhibitors, flame retardants, and flame retardant additives, exhibited poor flame retardancy and did not prevent post-molding shrinkage.

[0183] Furthermore, compared to Example 1, Comparative Example 7, which did not contain flame retardants and flame retardant additives, exhibited poor flame retardancy.

[0184] In addition, compared with Example 1, Comparative Example 8, which uses two types of resin represented by Chemical Formula 1 and an excess of resin represented by Chemical Formula 2, exhibits poor flame retardancy.

[0185] Furthermore, compared to Example 1, in Comparative Example 9, where only the first resin (represented by Chemical Formula 1) was used without the second resin, even when appropriate amounts of the resin (represented by Chemical Formula 2), post-molding shrinkage inhibitor, flame retardant, and flame retardant additive were added, the extrusion molding processability was poor due to the low viscosity.

[0186] Furthermore, compared to Example 1, in Comparative Example 10 where the second resin was used alone in the resin represented by Chemical Formula 1 without using the first resin, even when the resin represented by Chemical Formula 2, the post-molding shrinkage inhibitor, the flame retardant and the flame retardant additive were added in appropriate amounts, the extrusion molding processability was poor due to the high viscosity.

[0187] Furthermore, compared to Example 1, in Comparative Example 11 where the first and second resins were used in a mixing ratio exceeding an appropriate range in the resin represented by Chemical Formula 1, even when appropriate amounts of the resin represented by Chemical Formula 2, post-molding shrinkage inhibitor, flame retardant, and flame retardant additive were added, the extrusion molding processing performance was poor due to the low viscosity.

[0188] Furthermore, compared to Example 1, in Comparative Example 12, where the first resin and the second resin were used in a mixing ratio outside the appropriate range in the resin represented by Chemical Formula 1, and an excessive amount of the resin represented by Chemical Formula 2 was added, even when the post-molding shrinkage inhibitor, flame retardant, and flame retardant additive were added in appropriate amounts, the post-molding shrinkage resistance was poor, and the specific gravity was 1.0 or more, making it impossible to achieve lightweighting.

[0189] In summary, when preparing the thermoplastic flame-retardant resin composition of the present invention, by subjecting two or more different polyolefin resins to a predetermined molding process and mixing them with appropriate amounts of shrinkage inhibitors, halogenated flame retardants, and flame-retardant additives, the problem of post-molding shrinkage of very thin, large-area molded articles with a thickness of less than 0.3 mm can be solved without reducing the flame retardancy produced by the flame retardants and flame-retardant additives contained in the thermoplastic flame-retardant resin composition. Furthermore, the reliability of the molded articles can be improved, and a V-0 flame retardancy rating can be achieved in the UL94 vertical burning test. Therefore, the molded articles of the present invention are suitable for electrical and electronic products and automotive parts requiring such properties, such as insulating sheets for energy storage systems.

Claims

1. A thermoplastic flame-retardant resin composition comprising a resin represented by the following Chemical Formula 1; a resin represented by the following Chemical Formula 2; a post-molding shrinkage inhibitor represented by the following Chemical Formula 3; a halogen-based flame retardant; and a flame-retardant aid, wherein the resin represented by Chemical Formula 2 and the resin represented by Chemical Formula 1 are contained in a weight ratio of 1:6 to 1:7.4, the resin represented by Chemical Formula 1 includes a first resin in which n is an integer between 1000 and 3000 and a second resin in which n is an integer between 3000 and 6000, in a weight ratio of 1:1 to 1:3.8, [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] wherein, in Chemical Formula 1 and Chemical Formula 2, n is an integer between 1000 and 6000 and m is an integer between 2000 and 8000; in Chemical Formula 3, the carbon (C) symbol and the carbon-hydrogen bond symbol are omitted.

2. The thermoplastic flame retardant resin composition according to claim 1, wherein, the first resin has a melt index of 5 g / 10 min to 50 g / 10 min measured at 230°C under a load of 2.16 kg according to the ISO 1133 standard, and the second resin has a melt index of 0.01 g / 10 min to 4 g / 10 min measured at 230°C under a load of 2.16 kg according to the ISO 1133 standard.

3. The thermoplastic flame retardant resin composition according to claim 1, wherein, the resin represented by Chemical Formula 2 and the post-molding shrinkage inhibitor represented by Chemical Formula 3 are contained in a weight ratio of 1:0.5 to 1:1.

5.

4. The thermoplastic flame retardant resin composition according to claim 1, wherein, the halogen-based flame retardant is a bromine-based flame retardant.

5. The thermoplastic flame retardant resin composition according to claim 4, wherein, the bromine-based flame retardant includes one or more selected from the group consisting of tetrabromobisphenol A, decabromodiphenyl ether, octabromo-1,3,3-trimethyl-1-phenylindane, tetrabromobisphenol A-bis(2,3-dibromopropyl ether), and 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine.

6. The thermoplastic flame retardant resin composition according to claim 1, wherein, the flame-retardant aid is an antimony-based compound.

7. The thermoplastic flame retardant resin composition according to claim 6, wherein, the antimony-based compound includes one or more selected from the group consisting of antimony trioxide, a polysiloxane compound, black mica, white mica, iron oxide, tungsten oxide, and calcium carbonate.

8. A thermoplastic flame-retardant resin composition comprising: 19 to 29% by weight of a first resin represented by the following Chemical Formula 1, wherein n is an integer between 1000 and 3000, wherein the first resin has a melt index of 5 g / 10 min to 50 g / 10 min measured at 230°C under a load of 2.16 kg according to the ISO 1133 standard; 40 to 50% by weight of a second resin represented by the following Chemical Formula 1, wherein n is an integer between 3000 and 6000, wherein the second resin has a melt index of 0.01 g / 10 min to 4 g / 10 min measured at 230°C under a load of 2.16 kg according to the ISO 1133 standard; 6 to 14% by weight of a resin represented by the following Chemical Formula 2, wherein m is 2000 to 6000; 6 to 14% by weight of a post-molding shrinkage inhibitor represented by the following Chemical Formula 3; 6.5 to 11% by weight of a bromine-based flame retardant; and 1 to 4% by weight of an antimony-based flame-retardant aid, wherein the resin represented by Chemical Formula 2 and the resin represented by Chemical Formula 1 are contained in a weight ratio of 1:6 to 1:7.

4. [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] wherein, In Chemical Formula 1 and Chemical Formula 2, n is an integer between 1000 and 6000, and m is an integer between 2000 and 8000; in Chemical Formula 3, the carbon (C) symbol and the carbon-hydrogen bond symbol are omitted.

9. A molded article produced by molding the thermoplastic flame-retardant resin composition according to claim 1 or 8.

10. The molded article of claim 9, wherein, The molded article is an energy storage system component or a sheet having a thickness of 0.3 mm or less.

Images