Polyester resin composition, its manufacturing method and molded article manufactured therefrom

Abstract

The present invention relates to a polyester resin composition, a manufacturing method thereof, and a molded product manufactured from the same. The polyester resin composition of the present invention satisfies a balance of physical properties such as mechanical properties, electrical properties, fluidity, and flame retardancy to such an extent that it can replace conventional polyester materials containing halogen-based flame retardants by changing the raw materials used, and has the effect of providing excellent product reliability, heat resistance, and appearance quality.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0106540 ​​filed on August 25, 2022, and Korean Patent Application No. 10-2023-0090997, refiled on July 13, 2023 based thereon, and all contents disclosed in the documents of said Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a polyester resin composition, a manufacturing method thereof, and a molded article manufactured therefrom. More specifically, the present invention relates to a polyester resin composition that, by changing the raw materials used, satisfies a balance of physical properties such as mechanical properties, electrical properties, fluidity, and flame retardancy to the extent that it can replace halogen-containing polyester materials, and can provide excellent product reliability, heat resistance, and appearance quality, a manufacturing method thereof, and a molded article manufactured therefrom. [Background technology]

[0003] Conventionally, materials used for cooling applications, including computer cooling fans, have mainly been composite materials made of polybutylene terephthalate (PBT) resin reinforced with glass fiber in order to reduce weight and manufacturing costs.

[0004] In particular, flame retardancy is an important factor in the development of materials for computer cooling fans. As a specific example, in order to use the composite material mentioned above as a cooling fan material, it is necessary to develop a composite material that includes a non-halogen flame retardant.

[0005] The non-halogen flame retardants used in polybutylene terephthalate resin composite materials are mainly metal salt phosphorus flame retardants. However, when metal salt phosphorus flame retardants are used alone, it is difficult to achieve mechanical rigidity and flame retardancy equal to or greater than that of halogenated materials, so there is a need to develop technology to replace halogenated flame retardants. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Registration No. 5808253 (Registration Date: 2015.09.18) Summary of the Invention [Problem to be solved by the invention]

[0007] In order to solve the above-mentioned problems of the prior art, an object of the present invention is to provide a polyester resin composition that not only reduces costs but also achieves an excellent balance of physical properties, including excellent mechanical strength, electrical properties, fluidity, and flame retardancy, as a halogen-free polyester material.

[0008] Another object of the present invention is to provide a molded article using the polyester resin composition.

[0009] The above and other objects of the present invention can all be achieved by the present invention described below. [Means for solving the problem]

[0010] In order to achieve the above object, the present invention provides I) a polyester resin composition comprising a polybutylene terephthalate resin, a polyethylene terephthalate resin, an inorganic filler, an aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphoric acid ester, the intrinsic viscosity of the polyethylene terephthalate resin is smaller than the intrinsic viscosity of the polybutylene terephthalate resin; The melamine cyanurate is contained in an amount of 3.8% by weight or more relative to a total of 100% by weight of the polyester resin composition; or the polyester resin composition contains an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the melamine cyanurate is contained in an amount of 3.8% by weight or more relative to a total of 100% by weight of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor; the phosphate ester is contained in a range of 1.6 to 6.9% by weight relative to a total of 100% by weight of the polyester resin composition; or the polyester resin composition contains an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the phosphate ester is contained in a range of 1.6 to 6.9% by weight relative to a total of 100% by weight of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor; The inorganic filler contains SiO2, CaO, and Al2O3, and the content of SiO2 is greater than the total amount of CaO and Al2O3.

[0011] II) In the above I), the polybutylene terephthalate resin and the polyethylene terephthalate resin may each have an intrinsic viscosity (η) of 0.7 to 0.9 dl / g.

[0012] III) In I) or II), the polybutylene terephthalate resin is contained in a range of 24.8 to 41.7% by weight relative to 100% by weight of the total polyester resin composition; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the polybutylene terephthalate resin may be contained in a range of 24.8 to 41.7% by weight relative to 100% by weight of the total of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor.

[0013] IV) In the above I) to III), the polyethylene terephthalate resin may have a melting point of 243 to 256°C.

[0014] V) In the above I) to IV), the polyethylene terephthalate resin may be a recycled polyethylene terephthalate resin.

[0015] VI) In the above I) to V), the recycled polyethylene terephthalate resin may be a resin obtained by processing mineral water bottles.

[0016] VII) In I) to VI), the polyethylene terephthalate resin is contained in a range of 10 to 25% by weight relative to 100% by weight of the total polyester resin composition; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the polyethylene terephthalate resin may be contained in a range of 10 to 25% by weight relative to 100% by weight of the total of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor.

[0017] VIII) In the above I) to VII), the inorganic filler may contain 50 to 55% by weight of SiO2, 15 to 21% by weight of Al2O3, and 13 to 19% by weight of CaO.

[0018] IX) In I) to VIII), the inorganic filler is contained in a range of 20 to 40% by weight relative to a total of 100% by weight of the polyester resin composition; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the inorganic filler may be contained in a range of 20 to 40% by weight relative to a total of 100% by weight of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor.

[0019] X) In the above I) to IX), the aluminum salt of diethylphosphinic acid is contained in a range of 8.6 to 11.9% by weight relative to 100% by weight of the total of the polyester resin composition; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the aluminum salt of diethylphosphinic acid may be contained in a range of 8.6 to 11.9% by weight relative to 100% by weight of the total of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor.

[0020] XI) In I) to X), the melamine cyanurate is contained in a range of 3.8 to 5.2% by weight relative to 100% by weight of the total of the polyester resin composition; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the melamine cyanurate may be contained in a range of 3.8 to 5.2% by weight relative to 100% by weight of the total of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor.

[0021] XII) In the above I) to XI), the polyester resin composition contains an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and these may be contained in an amount of 0.1 to 10% by weight, relative to a total of 100% by weight of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor.

[0022] XIII) In I) to XII), the polyester resin composition may have a high-load heat distortion temperature of 190°C or higher as measured under 1.82 MPa in accordance with ISO 75, a flexural strength of 180 MPa or higher as measured on a 4.0 mm test piece using SPAN64 in accordance with ISO 178 at a rate of 2 mm / min, and a flexural modulus of 8000 MPa or higher.

[0023] XIV) The present invention provides a method for producing a granular granular composition comprising the steps of kneading and extruding a polybutylene terephthalate resin, a polyethylene terephthalate resin, an inorganic filler, an aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphoric acid ester; the intrinsic viscosity of the polyethylene terephthalate resin is smaller than the intrinsic viscosity of the polybutylene terephthalate resin; The melamine cyanurate is contained in an amount of 3.8% by weight or more relative to a total of 100% by weight of the polyester resin composition; or the polyester resin composition contains an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the melamine cyanurate is contained in an amount of 3.8% by weight or more relative to a total of 100% by weight of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor; the phosphate ester is contained in a range of 1.6 to 6.9% by weight relative to a total of 100% by weight of the polyester resin composition; or the polyester resin composition contains an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the phosphate ester is contained in a range of 1.6 to 6.9% by weight relative to a total of 100% by weight of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor; The inorganic filler comprises SiO2, CaO, and Al2O3, and the content of SiO2 is greater than the total amount of CaO and Al2O3; The polyethylene terephthalate resin is a recycled resin.

[0024] XV) The present invention includes a molded article characterized by comprising the polyester resin composition described above.

[0025] XVI) In the above XV), the molded product may be a cooling part. [Effects of the Invention]

[0026] The polyester resin composition according to the present invention provides a balance of mechanical properties, electrical properties, and flame retardancy that is equal to or better than that of conventional halogen-resistant flame-retardant polyester materials, and has an improved flow index, which allows for excellent processability, and can provide molded products with improved product reliability and appearance quality.

[0027] That is, the molded article produced from the polyester resin composition according to the present invention has the effect of achieving an excellent balance of mechanical properties such as tensile strength and flexural strength, and flame retardancy.

[0028] Furthermore, the molded article according to the present invention may be further suitable for cooling parts. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is a process flow chart showing the process of processing polyethylene terephthalate resin used in the examples from mineral water bottles. [Figure 2] The right side of the photograph shows the polyethylene terephthalate resin obtained by the process of Figure 1. The left side shows virgin PET resin produced by the DMT method, which is a transesterification reaction between dimethyl terephthalate (DMT) and ethylene glycol (EG), a method well known in the art. DETAILED DESCRIPTION OF THE INVENTION

[0030] The present invention will now be described in more detail to aid in understanding the invention.

[0031] The terms and words used in this specification and claims should not be interpreted in a limited way to their ordinary or dictionary meanings, but should be interpreted in a way that is consistent with the technical idea of ​​the present invention, taking into consideration that the inventor can appropriately define the concepts of terms in order to best describe the invention.

[0032] In this description, the meaning of "comprise" may be defined as "produced by polymerization comprising," "polymerized comprising," or "comprises as a unit derived from," unless otherwise defined.

[0033] Unless otherwise specified, all numbers, values, and / or expressions expressing quantities of ingredients, reaction conditions, polymer compositions, and formulations used in this description should be understood in all instances to be modified by the term "about," as such numbers are inherently approximations that reflect, among other things, various uncertainties of measurement that arise in obtaining such values. Also, when numerical ranges are disclosed in this description, such ranges are continuous and include every value from the minimum value to, and including, the maximum value of such range, unless otherwise specified. 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 specified.

[0034] In this description, when a range is recited for a variable, the variable is understood to include all values ​​within the recited range, inclusive of the recited endpoints of the range. For example, the range "5 to 10" is understood to include not only the values ​​5, 6, 7, 8, 9, and 10, but also any subranges such as 6 to 10, 7 to 10, 6 to 9, and 7 to 9, as well as any value between the integers within the recited range, such as 5.5 to 8.5 and 6.5 to 9. Also, the range 10 to 30% is understood to include values ​​such as 10%, 11%, 12%, 13%, etc., and all integers up to and including 30%, as well as any value between the integers within the recited range, such as 10.5%, 15.5%, 25.5%, etc.

[0035] As used herein, the term "hydrolysis stabilizer", unless otherwise specified, refers to a material incorporated to improve impact stability properties and the ability to control crystallization rate.

[0036] The term "flow index" as used in this description may be the melt flow index measured according to ISO 1133 at 260°C under a load of 5 kg, unless otherwise specified.

[0037] In this description, the weight % of a unit, a unit body, a block, etc. in a polymer can refer to the weight % of the monomer from which it is derived.

[0038] In addition, in this description, the weight % of units, units, blocks, etc. in a polymer can be measured by a measurement method commonly used in the technical field to which the present invention pertains. Alternatively, the content of input monomers can be defined as the content of units, etc. in the produced polymer, assuming that all monomers are polymerized.

[0039] The inventors of the present invention have found that when a non-halogenated polyester material is used as a cooling component material, and a composite material containing polybutylene terephthalate is manufactured to provide the rigidity and flame retardancy of the material, a polyester resin processed from a mineral water bottle is included, and the type and content of the non-halogenated flame retardant is adjusted, high rigidity can be achieved while achieving an excellent balance of mechanical properties, electrical properties, and flame retardancy, which led to the completion of the present invention.

[0040] Polyester resin composition A polyester resin composition according to an embodiment of the present invention includes a polybutylene terephthalate resin, a polyethylene terephthalate resin, an inorganic filler, an aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphoric acid ester.

[0041] The polybutylene terephthalate resin and polyethylene terephthalate resin are crystalline materials that impart moldability to polyester resin compositions containing them and impart flame retardancy to molded articles produced using the same.

[0042] The polyethylene terephthalate resin may be a recycled resin, and specifically, a resin obtained by processing mineral water bottles may be used.

[0043] Polybutylene terephthalate resin The polybutylene terephthalate resin is a crystalline resin that prevents the penetration of external chemicals. However, due to its crystallized structure, it improves the flowability of polyester resin compositions containing the polybutylene terephthalate resin during injection molding, resulting in excellent appearance quality.

[0044] The polybutylene terephthalate resin (PBT) may have a repeating unit represented by the following Chemical Formula 1:

[0045] [ka]

[0046] In the above Chemical Formula 1, n is an average degree of polymerization in the range of 50-200.

[0047] In one embodiment of the present invention, in order to increase the impact strength of the polyester resin composition, a copolymer obtained by copolymerizing the polybutylene terephthalate resin with an impact improving compound such as polytetramethylene glycol, polyethylene glycol, polypropylene glycol, aliphatic polyester, aliphatic polyamide, etc., or a modified polybutylene terephthalate resin obtained by mixing the polybutylene terephthalate resin with the impact improving compound may be used.

[0048] The polybutylene terephthalate resin may have a weight average molecular weight of, for example, 10,000 to 80,000 g / mol, 20,000 to 100,000 g / mol, 30,000 to 90,000 g / mol, 40,000 to 80,000 g / mol, or 50,000 to 70,000 g / mol. Mechanical properties can be improved within the above ranges.

[0049] Specifically, the weight-average molecular weight (MW) of the compound can be determined by placing tetrahydrofuran (THF) and the compound in a 1 ml glass vial to prepare a sample with a compound concentration of 1 wt%, filtering the standard (polystyrene) and the sample through a filter (pore size 0.45 μm) and injecting it into a GPC injector. The elution time of the sample can be compared with the calibration curve of the standard to obtain the molecular weight and MW distribution of the compound. An Infinity II 1260 (Agilient) can be used as the measuring instrument, with a flow rate of 1.00 mL / min and a column temperature of 40.0°C.

[0050] The content of the polybutylene terephthalate resin may be 20% by weight or more, 20 to 41% by weight, 24 to 42% by weight, or preferably 24.8 to 41.7% by weight, based on 100% by weight of a polyester resin composition containing the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and phosphate ester; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the polybutylene terephthalate resin may be 20% by weight or more, 20 to 41% by weight, 24 to 42% by weight, or preferably 24.8 to 41.7% by weight, based on 100% by weight of a polyester resin composition containing the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor. If the content is less than the above range, the solidification speed during injection molding may be slow, resulting in a longer cycle time. If the content is more than the above range, the amount of recycled polyethylene terephthalate resin used may be reduced, which may weaken the environmentally friendly concept and reduce flame retardancy.

[0051] The method for producing the polybutylene terephthalate resin is not particularly limited as long as it is a polymerization method commonly used in the technical field to which the present invention pertains, and if it meets the definition of the polybutylene terephthalate resin according to the present invention, it may be commercially purchased and used.

[0052] The intrinsic viscosity (η) of the polybutylene terephthalate resin may be 0.7 to 0.9 dL / g, or 0.75 to 0.85 dL / g. If the intrinsic viscosity is too low outside this range, the physical property reinforcing effect is reduced, resulting in a drawback that the effect of improving non-halogen flame retardancy is minimal. If the intrinsic viscosity is too high, the moldability is reduced, resulting in a drawback that problems may occur with the appearance of parts.

[0053] In this description, unless otherwise specified, the intrinsic viscosity is a value measured by completely dissolving a sample to be measured in a methylene chloride solvent at a concentration of 0.05 g / ml, filtering the solution through a filter, and measuring the filtrate at 20°C using an Ubbelohde viscometer.

[0054] The polybutylene terephthalate resin may have an intrinsic viscosity equal to or smaller than, and preferably smaller than, that of the polyethylene terephthalate resin described below, which can provide a physical property enhancing effect and an appearance quality improving effect.

[0055] The polybutylene terephthalate resin is not particularly limited, and may be prepared by a method known in the art, or may be a commercially available material.

[0056] Polyethylene terephthalate resin In this description, it is preferable to use recycled polyethylene terephthalate resin (hereinafter also referred to as "PET") from an environmental perspective.

[0057] As the recycled resin, polyethylene terephthalate resin obtained by processing commercially available mineral water bottles or waste thereof can be used alone.

[0058] The intrinsic viscosity of the polyethylene terephthalate resin may be 0.7 to 0.9 dL / g, or 0.7 to 0.8 dL / g. If the intrinsic viscosity is too low outside this range, the effect of reinforcing physical properties may be reduced, whereas if the intrinsic viscosity is too high, moldability may be reduced, which may cause problems with the appearance of parts.

[0059] The polyethylene terephthalate resin may have a repeating unit represented by the following chemical formula 2 as a basic structure.

[0060] [ka]

[0061] In the above chemical formula, n' is the average degree of polymerization in the range of 40-160.

[0062] The polyethylene terephthalate resin is not particularly limited and may be prepared by a method known in the art. The polyethylene terephthalate resin may have a melting point of 243°C or higher, specifically 243 to 256°C, which is preferable for improving the melt flow index of the polyester resin composition and therefore improving moldability.

[0063] The polyethylene terephthalate resin may have a crystallization temperature (Tm) of 243°C or higher, specifically 243 to 258°C. In this case, the melt flow index of the polyester resin composition can be improved, which is preferable for improving moldability.

[0064] In the present description, the melting point and crystallization temperature can be measured using methods known in the art, and as an example, they can be measured from heat absorption peaks using a differential scanning calorimeter (DSC).

[0065] In one embodiment of the present invention, the polyethylene terephthalate resin may be chips obtained by flaking mineral water bottles according to the process flow chart of FIG. 1, which will be described later.

[0066] The mineral water bottle may be made of a resin containing polyethylene terephthalate, which is produced by condensation polymerization of terephthalic acid and ethylene glycol, but is not limited thereto.

[0067] In terms of environmental considerations, it is preferable to use waste mineral water bottles as the mineral water bottles.

[0068] FIG. 1 below is a process flow chart that outlines the process for producing polyethylene terephthalate chips from waste mineral water bottles in the examples described below.

[0069] According to the following Figure 1, a sorting process is carried out to classify waste mineral water bottles into colored and colorless transparent bottles. The sorting can be done visually.

[0070] The PET is then crushed using a cutter. While the crushing size is not limited to this, it is preferable to use a cutter with a load of approximately 200 kg to perform the cleaning process and then crush it into fine particles of 3 to 5 mm in size, which is suitable for the washing, drying, and flaking processes described below. By increasing the surface area of ​​the crushed PET within this range, the drying efficiency in the subsequent drying process can be improved, and a uniform reaction with the thickener can be achieved.

[0071] In the next step, the primary ground material is subjected to an additional cleaning process, followed by drying and flaking.

[0072] The drying involves removing moisture from the pulverized material, then blending a thickener therewith and carrying out primary drying (preliminary drying), followed by secondary drying, after which a dehumidification treatment can be carried out.

[0073] In this case, the primary drying is carried out under conditions of 120 to 140°C so that the moisture content of the PET pulverized material becomes about 1000 ppm, while a thickener is blended and reacted uniformly.

[0074] For example, the primary drying involves placing the selected PET pulverized material and thickener in a friction dryer, and drying the material to a moisture content of 1000 ppm by continuously passing heated air at 120 to 140°C through the dryer at a temperature of 140°C and a stirrer speed of 50 rpm for about 2 hours.

[0075] The thickener may be any compound that undergoes a thickening reaction without melting at the primary drying temperature of 140°C mentioned above and the secondary drying temperature (around 165°C) mentioned below. As a specific example, a carbodiimide-based thickener may be used.

[0076] The carbodiimide thickener is a known compound, such as carbodiimide or polycarbodiimide, and the thickener is added by appropriately adjusting the blending ratio depending on the intrinsic viscosity suitable for the target product. For example, the thickener can be added in an amount of 0.25 to 0.75% by weight based on the total weight of PET.

[0077] The dehumidification treatment is a step of drying and dehumidifying the PET reaction mixture so that the water content of the PET reaction mixture is less than 50 ppm to prevent hydrolysis of the PET in the reaction mixture, thereby obtaining a dried PET product.

[0078] In this description, ppm is by weight unless otherwise specified.

[0079] The dehumidification process is known to involve placing the PET reaction mixture in a drying hopper, and drying and dehumidifying the PET reaction mixture to a moisture content of less than 50 ppm while injecting high-temperature, moisture-removed hot air from a dehumidifier into the hopper under conditions of a dryer temperature of 165°C, a dew point of -60 to -40°C, and a residence time of about 5 hours.

[0080] The flake treatment is a process of sorting flakes to sizes of about 5 mm using an optical flake sorter, and the sorted product is extruded at a temperature range of 200 to 270°C.

[0081] Specifically, the extrusion process involves adding a thickener to PET dry flakes that have been dried and dehumidified to a moisture content of less than 50 ppm, melt-extruding them at a melting temperature, and then physically removing foreign matter from the molten extrudate to obtain a PET melt.

[0082] In this case, the additional thickener cannot be used because it has a lower melting temperature than the thickeners mentioned above and melts at the dryer temperature of 140°C and the dryer temperature of the process described below, which is around 165°C.

[0083] For reference, if an additional thickener is added together with the aforementioned thickeners, it will melt in the dryer, making it impossible to operate the primary drying process and dehumidification treatment. Therefore, it must be added separately to the extrusion process where the PET reaction mixture is melted.

[0084] The additional thickener may be a compound known as an oxazoline-based thickener, such as oxazoline or 1,3-phenylenebisoxazoline, and may be added in an amount of, for example, 0.1 to 0.75 wt % based on the total weight of the PET melt.

[0085] In addition, by adjusting the compounding ratio of the thickener used in the primary drying step and the thickener used in the extrusion step, it is possible to provide an intrinsic viscosity suitable for producing the desired product.

[0086] As an example of the extrusion process, PET dried material that has been dried and dehumidified to a moisture content of less than 50 ppm and an additional thickener are fed into an extruder, and melt-extruded under conditions of a melt temperature of 275 to 280°C and a maximum melt pressure of 110 bar.

[0087] The obtained molten extrudate is passed through a 20 micron SUS filter at a vacuum of 10 mbar to remove foreign matter, obtaining a high-purity PET melt, which is then cooled and cut to form a PET product of a certain shape.

[0088] As an example, the molding can be carried out by cutting high-purity PET melt into spherical PET (hereinafter also referred to as "PET chips") with a diameter of 2.8 mm in circulating water at 90°C under conditions of a die plate temperature of 320°C and a blade rotation speed of 3200 rpm.

[0089] The PET chip manufacturing process requires temperature control to maintain residual heat of 140°C or higher, which allows the surface of the PET chip to be crystallized using the residual heat remaining in the molding process, thereby providing the desired intrinsic viscosity.

[0090] In the PET chip manufacturing process, the PET chips pass through an in-line crystallizer equipped with a vibrating conveyor for about 15 minutes, crystallizing the surface of the PET chips. This eliminates the problem of agglomeration that occurs when the PET chips are dried without surface crystallization.

[0091] The collected recycled PET chips are compounded with talc, coupling agents, glass fibers, etc. as needed to produce recycled resin.

[0092] The polyethylene terephthalate resin may be contained in an amount of 10 wt% or more, 10 to 40 wt%, 10 to 30 wt%, or 10 to 25 wt%, relative to a total of 100 wt% of a polyester resin composition containing polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphate ester; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the polyethylene terephthalate resin may be contained in an amount of 10 wt% or more, 10 to 40 wt%, 10 to 30 wt%, or 10 to 25 wt%, relative to a total of 100 wt% of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor. If the content is less than the above range, the amount of recycled polyethylene terephthalate resin used will decrease, and the environmentally friendly concept will be weakened. If the content is more than the above range, the physical property reinforcement effect and moldability will decrease, which may cause problems with the appearance of the part.

[0093] inorganic filler The inorganic filler included in this description may be a material containing SiO2, CaO, and Al2O3, and the SiO2 content may be greater than the total amount of CaO and Al2O3. Preferably, glass fiber having a SiO2 content greater than the total amount of CaO and Al2O3 may be used.

[0094] According to an embodiment of the present invention, the glass fiber may be of a type that reinforces the rigidity of a molded article produced using the polyester resin composition of the present invention and improves the mechanical properties.

[0095] The inorganic filler according to one embodiment of the present invention may contain, for example, 50 to 55 wt% silica, and specifically, glass fiber containing 50 to 55 wt% silica, 15 to 28 wt% alumina, and 13 to 26 wt% calcium oxide, preferably glass fiber containing 50 to 55 wt% silica, 15 to 21 wt% alumina, and 13 to 19 wt% calcium oxide. When glass fiber contained within the above ranges is used, a polyester resin composition having an excellent balance of processability, specific gravity, and mechanical properties can be obtained, and molded products with high heat resistance, high rigidity, and high toughness can be provided.

[0096] In the present invention, the silica content in the reinforcing agent can be measured or confirmed using XRF (X-ray fluorescence spectrometry).

[0097] The glass fiber described herein may be a glass fiber having a circular cross section or a flat cross section, and when it has the above-mentioned range and cross section, high rigidity, light weight, and appearance quality can be ensured.

[0098] For example, when the aspect ratio (L / D) of the glass fiber, which is the ratio of length (L) to diameter (D), is, for example, 1:1 to 1:4, specifically 1:1 to 1:3, and more specifically 1:1, the polyester resin composition of the present invention can provide high strength and high toughness as well as improved elongation and surface appearance. For example, when the aspect ratio is 1:3 to 1:4, and more specifically 1:4, the polyester resin composition of the present invention can provide a product that is advantageous in terms of flatness, deformation, and orientation as well as high strength and high toughness.

[0099] In this description, the diameter and length can be measured using a scanning electron microscope (SEM). Specifically, 20 inorganic fillers are selected using a scanning electron microscope, and the diameter and length of each are measured using an icon bar capable of measuring diameter, and the arithmetic mean is then calculated as the average diameter and average length.

[0100] The average diameter may be, for example, 10 to 13 μm, specifically 10 to 11 μm, and the average length may be, for example, 2.5 to 6 mm, specifically 3 to 4 mm. When the above-mentioned ranges are satisfied, there is an effect of improving processability and improving the tensile strength of a molded product produced by molding the polyester resin composition of the present invention.

[0101] The cross section of the glass fiber may have a shape such as a circle, a rectangle, an oval, a dumbbell, or a diamond.

[0102] In one embodiment of the present invention, the glass fiber may be used together with other inorganic fibers, and the inorganic fibers may be one or more selected from the group consisting of carbon fiber, basalt fiber, and natural fibers such as kenaf or hemp.

[0103] In one embodiment of the present invention, the glass fibers may be treated with a sizing agent during fiber manufacturing or post-processing. Such sizing agents include lubricants, coupling agents, surfactants, and the like.

[0104] The lubricant is mainly used to form good strands during the production of glass fibers, and the coupling agent enables good adhesion between the glass fibers and the base resin. When appropriately selected in consideration of the types of base resin and glass fibers, the coupling agent can impart excellent physical properties to the polyester resin composition.

[0105] The coupling agent can be used by directly treating the glass fiber or by adding it to an organic matrix. In order to fully utilize the performance of the coupling agent, the content of the coupling agent must be appropriately selected.

[0106] Examples of the coupling agent include amine-based, acrylic-based, and silane-based agents, and among these, it is preferable to use silane-based agents.

[0107] Specific examples of the silane system include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-(β-aminoethyl)γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and β-(3,4-epoxyethyl)γ-aminopropyltrimethoxysilane.

[0108] The content of the inorganic filler described herein may be 10 to 38 wt%, 15 to 38 wt%, 15 to 35 wt%, 20 to 40 wt%, or 25 to 35 wt%, relative to a total of 100 wt% of a polyester resin composition containing polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphate ester; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the inorganic filler may be contained in a range of 10 to 38 wt%, 15 to 38 wt%, 15 to 35 wt%, 20 to 40 wt%, or 25 to 35 wt%, relative to a total of 100 wt% of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor. If the content is less than the above range, there is a drawback that cracks occur in molded articles produced using a polyester resin composition containing the same, and if the content exceeds the above range, there is a drawback that molded articles produced using a polyester resin composition containing the same do not fit the dimensions or have a reduced appearance quality.

[0109] Polyester resin composition The polyester resin composition according to an embodiment of the present invention may further include a suitable additive, such as an aluminum salt of diethylphosphinic acid, melamine cyanurate, or a phosphate ester, as a non-halogen flame-retardant material to provide flame retardancy and improved mechanical properties equivalent to or similar to those of halogen flame-retardant materials.

[0110] Aluminum salt of diethylphosphinic acid Specifically, the aluminum salt of diethylphosphinic acid is included as a non-halogen flame retardant, and not only provides the flame retardancy required during extrusion and injection processing of the polyester resin composition, but also provides sufficient flame retardancy during long-term storage of the polyester resin composition.

[0111] The aluminum salt of diethylphosphinic acid can form char on the surface of the polymer, thereby improving the flame retardancy of the composition.

[0112] The content of the aluminum salt of diethylphosphinic acid may be 9 wt % or more, 9 to 15 wt %, 9 to 12 wt %, or 8.6 to 11.9 wt %, relative to 100 wt % of the total weight of the polyester resin composition including the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and phosphate ester; or the polyester resin composition may include an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the content of the aluminum salt of diethylphosphinic acid may be 9 wt % or more, 9 to 15 wt %, 9 to 12 wt %, or 8.6 to 11.9 wt %, relative to 100 wt % of the total weight of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor. When the above range is satisfied, char is formed on the surface of the polymer, thereby improving the flame retardancy of the composition.

[0113] In one embodiment of the present invention, the aluminum salt of diethylphosphinic acid may be a commercially available product.

[0114] Melamine Cyanurate The melamine cyanurate can generate an inert gas to improve flame retardancy.

[0115] The content of the melamine cyanurate may be 3.8% by weight or more, 3.8 to 10% by weight, 3.8 to 5.8% by weight, or 3.8 to 5.2% by weight, based on 100% by weight of a polyester resin composition containing polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphate ester; or the polyester resin composition may contain an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the content of the melamine cyanurate may be 3.8% by weight or more, 3.8 to 10% by weight, 3.8 to 5.8% by weight, or 3.8 to 5.2% by weight, based on 100% by weight of a combined total of polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor. When the above range is satisfied, the inert gas can be generated sufficiently to improve the flame retardancy of the composition.

[0116] In one embodiment of the present invention, the melamine cyanurate may be a commercially available product.

[0117] phosphate ester Specifically, the phosphate ester is included as a non-halogen flame retardant, and can generate an inert gas to improve flame retardancy.

[0118] The content of the phosphate ester may be 1.6 wt % or more, 1.6 to 6.9 wt %, 2 to 6.9 wt %, or 2 to 6.5 wt %, relative to 100 wt % of the total weight of the polyester resin composition including the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and phosphate ester; or the polyester resin composition may include an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, and the content of the phosphate ester may be within the range of 1.6 wt % or more, 1.6 to 6.9 wt %, 2 to 6.9 wt %, or 2 to 6.5 wt %, relative to 100 wt % of the total weight of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor. When the above range is satisfied, the inert gas can be generated sufficiently to improve the flame retardancy of the composition.

[0119] In one embodiment of the present invention, the phosphate ester may be a commercially available product.

[0120] additives According to one embodiment of the present invention, the composition may further include four or more additives selected from an anti-dripping agent, a low viscosity polyethylene-based lubricant, a hydrolysis inhibitor, a phenolic antioxidant, and a phosphite antioxidant.

[0121] In one embodiment of the present invention, the polyester resin composition includes an anti-dripping agent, a heat stabilizer, a polyethylene-based lubricant, and a hydrolysis inhibitor, which may be contained in a total amount of 0.1 to 10 wt%, 0.1 to 7 wt%, or 0.1 to 5 wt%, based on a total of 100 wt% of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, anti-dripping agent, heat stabilizer, polyethylene-based lubricant, and hydrolysis inhibitor. Within these ranges, the physical properties of the resin composition are not affected, and the additive's inherent properties are effectively expressed.

[0122] The anti-dripping agent is not particularly limited as long as it can provide an anti-dripping effect to the polyester resin composition containing the anti-dripping agent. For example, when a tetrafluoroethylene resin is used, it is preferable because the flame retardancy can be improved through the anti-dripping effect.

[0123] In one embodiment of the present invention, the anti-dripping agent may be a commercially available product.

[0124] The anti-dripping agent may be contained in a range of 0.01 to 5 wt%, 0.1 to 3 wt%, 0.1 to 2 wt%, 0.1 to 1 wt%, or 0.1 to 0.5 wt%, based on a total of 100 wt% of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and anti-dripping agent. If the content of the anti-dripping agent is too high outside this range, molded articles produced using a polyester resin composition containing the anti-dripping agent may suffer from reduced moldability and quality degradation, while if the content is below this range, the anti-dripping effect may not be sufficiently exhibited.

[0125] The lubricant may be an olefin wax, which provides the polyester resin composition with excellent mold releasability and injectability.

[0126] The lubricant is not particularly limited as long as it can ensure the ease of removal and flowability of the injection screw used to produce a molded article from a polyester resin composition containing the lubricant.

[0127] The lubricant is not particularly limited as long as it can be used in the present invention and can ensure the above properties, but preferably contains an olefin-based wax, and more preferably contains a polyethylene-based wax.

[0128] In one embodiment of the present invention, the polyethylene wax may be a commercially available product.

[0129] The lubricant may be contained in an amount of 0.01 to 5 wt%, 0.1 to 3 wt%, 0.1 to 2 wt%, 0.1 to 1 wt%, or 0.1 to 0.5 wt%, based on a total of 100 wt% of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and lubricant. When the amount is within the above range, excellent mold releasability and ejection properties can be sufficiently provided.

[0130] In one embodiment of the present invention, the hydrolysis inhibitor may be any known type that does not adversely affect the polyester resin composition of the present invention. Among commercially available substances, inorganic phosphate compounds such as monobasic sodium phosphate having the chemical formula NaHPO may be used.

[0131] The hydrolysis inhibitor may be contained in an amount of 0.01 to 5 wt%, 0.1 to 3 wt%, 0.1 to 2 wt%, 0.1 to 1 wt%, or 0.1 to 0.5 wt%, based on a total of 100 wt% of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and hydrolysis inhibitor. When the amount is within the above range, excellent hydrolysis resistance can be sufficiently provided.

[0132] The phenolic antioxidant and the phosphite antioxidant are not particularly limited as long as they can reinforce the heat stabilizing effect and prevent the polyester resin composition or the molded article from being degraded due to high temperatures.

[0133] The thermal stabilizer is not particularly limited as long as it can ensure the above properties, but as described above, the use of a phenolic antioxidant can further improve the thermal stability of the polymer contained in the polyester resin composition. Specifically, the phenolic antioxidant can remove radicals and protect the polymer during molding of the polyester resin composition.

[0134] In the present invention, a hindered phenol-based stabilizer having a crystallization temperature (Tm) of 110 to 130° C. may be contained. Specific examples include tetrakis[ethylene-3-(3,5-di-t-butyl-hydroxyphenyl)propionate], octadecyl 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, or a mixture thereof.

[0135] The thermal stabilizer is not particularly limited as long as it can ensure the above properties. For example, the phosphite antioxidant (high phenolic antioxidant) may include a phosphite-based stabilizer having a melting temperature (Tm) of 180 to 240°C. Specific examples include tris(2,4-di-tert-butylphenyl)phosphite, 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane, bis(2,4-dicumylphenyl)pentaerythritol diphosphite, or a mixture thereof.

[0136] In one embodiment of the present invention, the phosphite antioxidant may be a commercially available product.

[0137] The heat stabilizer may be contained in an amount of 0.01 to 5 wt%, 0.01 to 3 wt%, 0.01 to 2 wt%, 0.01 to 1 wt%, or 0.05 to 0.5 wt%, based on a total of 100 wt% of the polybutylene terephthalate resin, polyethylene terephthalate resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, and heat stabilizer. If the content of the heat stabilizer is too high, molded articles produced using the polyester resin composition containing the heat stabilizer may have appearance problems such as unevenness on the surface, which may impair the appearance quality.

[0138] The polyester resin composition may preferably be a polyester resin composition for cooling parts such as cooling fans for computers or notebook computers.

[0139] Method for producing polyester resin composition The method for producing the polyester resin composition of the present invention will be described below. The method for producing the polyester resin composition of the present invention includes all of the above-mentioned polyester resin compositions.

[0140] As an example, a method for producing the polyester resin composition described herein includes the steps of feeding polybutylene terephthalate resin, polyethylene terephthalate resin, an inorganic filler, an aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphoric acid ester into an extruder, melt-kneading, and extruding.

[0141] The melt-kneading step may include, for example, other additives as described above.

[0142] The melt-kneading and extruding steps may be performed using, for example, one or more selected from the group consisting of a single-screw extruder, a twin-screw extruder, and a Banbury mixer, preferably a twin-screw extruder, which may be used to uniformly mix the composition and then extrude the mixture to obtain a polyester resin composition in the form of an extrudate. In this case, there is an effect of providing a polyester resin composition that is excellent in plating adhesion and appearance quality without deterioration in mechanical properties and thermal properties.

[0143] The polyester resin composition according to the present invention can be prepared by a method known in the art. For example, the polyester resin composition can be prepared in the form of an extrudate by melt-extruding a mixture of each component and other additives in an extruder, and the extrudate can be used for injection and extrusion molded products.

[0144] In one embodiment of the present invention, the extrudate is extruded at a temperature of 250 to 280°C, or 260 to 270°C, where the temperature refers to the temperature set in the cylinder.

[0145] The mold temperature during injection is preferably in the range of 40 to 120°C. If the mold temperature is below 40°C, the appearance characteristics may be deteriorated, and if it is above 120°C, the extrudate may stick to the mold, reducing demoldability and increasing the cooling rate. The mold temperature may specifically be 60 to 88°C, 70 to 80°C, or 72 to 78°C. When this range is satisfied, even if the temperature of the mold into which the molten polyester resin composition is injected during injection molding of an injection-molded product is adjusted, injection deviation at all points of the molded product can be minimized, improving injection characteristics and heat resistance at the same time.

[0146] The injection step can be carried out, for example, using an injection machine in which the hopper temperature or the nozzle temperature is set to 260 to 280°C.

[0147] According to one embodiment of the present invention, the injection speed of the molten polyester resin composition during injection molding of the injection-molded article may be 30 to 100 mm / s. Specifically, the injection speed of the molten polyester resin composition during injection molding of the injection-molded article may be 35 to 95 mm / s, 50 to 80 mm / s, or 60 to 70 mm / s. When this range is satisfied, even if the temperature of the mold into which the molten polyester resin composition is injected during injection molding of the injection-molded article is adjusted, injection deviation can be minimized at all points of the molded article, improving injection properties and hydrolysis resistance at the same time.

[0148] For example, the method for producing a polyester resin composition of the present invention includes the steps of kneading and extruding polybutylene terephthalate resin, polyethylene terephthalate resin, glass fiber, and other additives, and is characterized in that the polyethylene terephthalate resin is a recycled resin. In this case, a balance of physical properties such as rigidity, processability, and specific gravity can be achieved.

[0149] The resin used to process the mineral water bottle may be a product obtained by processing an extrusion of a mineral water bottle made from polyester resin having an intrinsic viscosity of 0.5 to 0.9 dl / g.

[0150] According to an embodiment of the present invention, the mineral water bottle may include a step of melt-kneading and extruding a processed resin.

[0151] As a specific example, the method may include the steps of: forming an extrudate of a mineral water bottle having an intrinsic viscosity of 0.5 to 0.9 dL / g to obtain a polyethylene terephthalate resin having an intrinsic viscosity of 0.7 to 0.8 dL / g; and melt-kneading and extruding 10 to 37.5 wt % of the polyethylene terephthalate resin, 26.7 to 54 wt % of polybutylene terephthalate resin, and 10 to 43 wt % of an inorganic filler.

[0152] In this case, various molding methods used in the art may be used, and the molding form may be, for example, a chip form taking into consideration convenience of use.

[0153] Furthermore, a molded article containing the polyester resin composition of the present invention will be described. The description of the molded article containing the polyester resin composition of the present invention includes all of the above-mentioned polyester resin composition and the method for producing the same.

[0154] Molded product The polyester resin composition of the present invention can be effectively used for molded articles requiring moldability, mechanical properties, high load heat distortion temperature, and halogen-free flame retardancy due to the sufficient complementarity between components.

[0155] The molded product may be, for example, a cooling part that requires high heat resistance and injection properties.

[0156] As another example, the molded article may be a computer cooling fan.

[0157] The molded article may be manufactured by a method commonly used in the art, for example, injection molding, injection compression molding, extrusion molding (sheet casting), press molding, pressure molding, hot bending molding, compression molding, calendar molding, rotational molding, etc., using a melt-kneaded product, extrudate, or sheet (plate) molded from the polyester resin composition according to the present invention as a raw material.

[0158] For example, the polyester resin composition described herein can be prepared by melt-kneading and extruding at 250 rpm using a twin-screw extruder (φ40, L / D: 42, equipped with SM Platek) set at 260°C. The extrudate can be produced by feeding polybutylene terephthalate resin, recycled polyester resin, inorganic filler, aluminum salt of diethylphosphinic acid, melamine cyanurate, phosphate ester, and additives into the main inlet at a feed rate (flow ratio, F / R) of 35 kg / h, and feeding inorganic filler into the auxiliary (side) inlet at a feed rate of 15 kg / h.

[0159] The extrudate can be fed into an injection molding machine to produce a molded article.

[0160] To confirm the physical properties of the polyester resin composition described herein, the extrudate can be injected into an injection molding machine (ENGEL, 80 ton) at an injection temperature of 260°C, a mold temperature of 80°C, and an injection speed of 30 mm / sec to produce ISO standard test pieces.

[0161] The polyester resin composition of the present invention has, for example, a flow index of 15 g / 10 min or more, or 15 to 30 g / 10 min, as measured in accordance with ISO 1133, and a specific gravity of 1.5 g / cm 3, as measured in accordance with ISO 1183. 3 More than 1.55g / cm 3 or more, or 1.55 to 1.60 g / cm 3 In this case, excellent processability can be provided.

[0162] In this description, the flow index can be measured at 265°C under a load of 2.16 kg, and the specific gravity can be measured at 23°C.

[0163] Furthermore, the polyester resin composition described herein may have a high load heat distortion temperature measured in accordance with ISO 75 of, for example, 190°C or higher, 200°C or higher, 200 to 210°C, or 202 to 205°C. In this case, an excellent heat distortion temperature can be provided.

[0164] In this description, the high load heat distortion temperature can be measured in accordance with ISO 75 under a high load of 1.82 MPa.

[0165] The polyester resin composition of the present invention may have a flexural strength of 180 MPa or more, 182 MPa or more, or 182 to 200 MPa, measured on a 4.0 mm test piece in accordance with ISO 178, and a flexural modulus of 8000 MPa or more, 9000 MPa, 9000 to 11000 MPa, or 9450 to 11000 MPa, as measured on a 4.0 mm test piece in accordance with ISO 178. In this case, excellent warpage resistance and processability can be provided.

[0166] In this description, flexural strength and flexural modulus can be measured in accordance with ISO 178 using a SPAN64 at a speed of 2 mm / min.

[0167] The polyester resin composition of the present invention may have a tensile strength of 115 MPa or more, 116 MPa or more, or 117 to 135 MPa when measured on a 4.0 mm test piece in accordance with ISO 527-1, and a tensile elongation of 1.5% or more, 2.0% or more, or 2.4 to 3% when measured in accordance with ISO 527-2, for example. In this case, excellent high toughness can be provided.

[0168] In this description, the tensile strength and tensile elongation can be measured on a test piece at 23° C. at a speed of 5 mm / min.

[0169] Furthermore, the polyester resin composition described herein has, for example, a Charpy impact strength of 6.5 kJ / cm as measured in accordance with ISO 179 / 1eA. 2 Above, 6.8kJ / cm 2 or more, or 6.9 to 7.9 kJ / cm 2 In this case, excellent high impact resistance can be provided.

[0170] In this description, Charpy impact strength can be measured on notched specimens at 23°C.

[0171] The polyester resin composition of the present invention may have a flame retardancy of V-0 or higher when measured using a test piece having a thickness of 0.8T in accordance with, for example, the UB 94 V test, thereby providing excellent flame retardancy.

[0172] The molded article may be specifically a cooling part, particularly a computer cooling fan that requires both thermal properties and flame retardancy, but is not limited to a specific product.

[0173] Molded articles manufactured from a polyester resin composition according to an embodiment of the present invention use a halogen-free composition instead of conventional materials, but have improved flame retardancy by forming char and inert gas on the polymer surface. They also have a balanced set of physical properties, including mechanical properties, thermal properties, fluidity, and flame retardancy, resulting in improved product reliability and appearance quality.

[0174] In describing the polyester resin composition of the present invention, its production method, and molded articles, other conditions and equipment not explicitly described can be appropriately selected within the range commonly used in the art and are not particularly limited.

[0175] The present invention will now be described in detail with reference to exemplary embodiments thereof so that those skilled in the art can easily practice the present invention. However, the present invention may be embodied in various different forms and should not be construed as being limited to the exemplary embodiments set forth herein.

[0176] [Example] The specifications of each component used in the examples are as follows, where % means % by weight. (A) Polybutylene terephthalate resin: Intrinsic viscosity (IV) 0.8 dl / g (B) Recycled polyethylene terephthalate: Mineral water bottles were processed according to the process flow chart in Figure 1 below, resulting in a homo-type white chip with an intrinsic viscosity (IV) of 0.7 dl / g (see the right side of Figure 2 below). (C) Inorganic filler (C-1) Glass fiber (silica content 44 wt%, alumina 14 wt%, calcium oxide 36 wt%) with a diameter of 10 μm and a length of 3 mm (C-2) Glass fiber (silica content 52 wt%, alumina 18 wt%, calcium oxide 16 wt%) with a diameter of 10 μm and a length of 3 mm (D) Flame retardants (D-1) Aluminum salt of diethylphosphinic acid (D-2) Melamine cyanurate (D-3) Phosphate ester: Tetrakis(2,6-dimethylphenyl)1,3-phenylene bisphosphate (D-4) Brominated aromatic carbonate oligomer (D-5) Antimony trioxide flame retardant synergist <Additives> (E) Anti-drip agent: Teflon (F) Heat stabilizer: A 1:1 mixture of phenolic antioxidant and phosphite antioxidant. (G) Polyethylene lubricant: LDPE wax (H) Hydrolysis inhibitor (transesterification inhibitor): Sodium monophosphate, chemical formula NaH2PO4

[0177] Examples 1 to 4 and Comparative Examples 1 to 7 The raw materials of the polyester resin composition shown in Table 1 below were mixed and extruded to prepare a polyester resin composition having a uniform dispersion in the form of an extrudate. The extrudate was then heated and injected into a mold frame, followed by cooling to produce a test piece through an injection process.

[0178] Specifically, each of the components was added in the amounts shown in Table 1 below, and melt-kneaded in a temperature range of 250 to 280°C using a twin-screw extruder with L / D = 42 and Φ = 40 mm to produce a resin composition in the form of an extrudate.

[0179] The extrudates were dried at 100°C for at least 4 hours and then injected into an 80-ton injector (Engel, Victory 80) at an injection temperature of 260-280°C, a mold temperature of 80°C, and an injection speed of 30 mm / s to prepare test specimens for evaluating mechanical properties.

[0180] The physical properties of the prepared test specimens having a thickness of 3.2 mm, a width of 12.7 mm, and a gauge section (elongation measurement) of 115 mm were measured by the following methods, and the results are shown in Table 2 below.

[0181] [Table 1]

[0182] Experimental Example 1: Evaluation of the physical properties of molded product test pieces The physical properties of the molded test pieces produced in Examples 1 to 4 and Comparative Examples 1 to 7 were evaluated according to the following evaluation methods. -Specific gravity: measured according to ISO 1183 (23°C) -Melt Flow Rate: Measured in accordance with ISO 1133 (265°C, 2.16 kg) -Tensile strength and elongation: measured according to ISO 527-1, 2 (5mm / min, 23°C) -Flexural strength and flexural modulus: Measured in accordance with ISO 178 (4.0 mm, SPAN 64, speed 2 mm / min, 23°C) - Charpy impact strength (IZOD): measured in accordance with ISO 179 / 1eA (Notched, 23°C) - Heat distortion temperature: measured according to ISO 75 (high load 1.82 MPa) - Flame retardancy: Measured in accordance with UL94 V test (V-0, 0.8T)

[0183] The results measured according to the above evaluation criteria are shown in Table 2 below.

[0184] [Table 2]

[0185] As shown in Tables 1 and 2, the polyester resin compositions of Examples 1 to 4 according to the present invention have high impact strength, flexural modulus, and high-load heat distortion temperature. Therefore, molded products manufactured using the compositions basically satisfy mechanical properties such as impact strength, tensile strength, and flexural strength, while also having excellent halogen-free flame retardancy and high-load heat distortion temperature. They also have reduced gas generation during injection, thereby providing excellent product reliability and appearance quality.

[0186] On the other hand, in Comparative Example 3, which uses an inorganic filler with a silica content outside the composition of the present invention, it was confirmed that not only did the tensile strength and flexural strength deteriorate, but the flow index was also poor compared to Examples 1 to 4.

[0187] In addition, Comparative Examples 1 and 2, which used an inorganic filler with a silica content outside the composition of the present invention and did not use a polyethylene terephthalate resin or a hydrolysis inhibitor, respectively, were found to have poor mechanical properties such as tensile strength, flexural strength, flexural modulus, and impact strength, as well as poor flow index, when compared with Examples 1 to 4. In particular, of Comparative Examples 1 and 2, Comparative Example 1, which used an excessive amount of aluminum salt of diethylphosphinic acid, showed a significant deterioration in flow index and reduced processability.

[0188] In addition, Comparative Example 2, in which the amount of polybutylene terephthalate resin was increased more than in Comparative Example 1 and the amount was excessive, was found to have poor mechanical properties such as tensile strength, flexural strength, flexural modulus, and impact strength compared to Examples 1 to 4, and also showed flame retardancy that did not reach the level of halogen flame retardancy.

[0189] Furthermore, it was confirmed that Comparative Example 4, in which the content of aluminum salt of diethylphosphinic acid and the content of melamine cyanurate did not reach the ranges according to the present invention, had a worse flame retardancy compared to Examples 1 to 4.

[0190] Furthermore, it can be seen that Comparative Example 5, which did not use a phosphate ester as a constituent type of non-halogen flame retardant, and Comparative Example 6, which used a smaller amount of phosphate ester than the content according to the present invention, had a worse flame retardancy compared to Examples 1 to 4.

[0191] On the other hand, in Comparative Example 7, in which the content of the phosphate ester was used in an excessive amount outside the content range according to the present invention and a small amount of polybutylene terephthalate resin was used, mechanical properties such as tensile elongation, flexural strength, and impact strength were poor compared to Examples 1 to 4.

[0192] That is, the polyester resin composition according to one embodiment of the present invention is characterized by using a non-halogen-based material as a cooling component material, thereby simultaneously providing flame retardancy, rigidity, and thermal properties. Molded products manufactured from the composition use a halogen-free composition instead of conventional materials, but improve flame retardancy by forming char and inert gas on the polymer surface. They also have a balanced physical property profile, including mechanical properties, electrical properties, fluidity, and flame retardancy, resulting in improved product reliability and appearance quality.

Claims

1. A polyester resin composition comprising polybutylene terephthalate resin, polyethylene terephthalate resin, glass fiber, aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphoric acid ester, the polybutylene terephthalate resin is contained in an amount of 24 to 41.7% by weight relative to 100% by weight of the total of the polyester resin composition; the polyethylene terephthalate resin is contained in an amount of 10 to 25% by weight relative to 100% by weight of the total of the polyester resin composition; the glass fiber is contained in an amount of 20 to 40% by weight relative to 100% by weight of the total of the polyester resin composition; the aluminum salt of diethylphosphinic acid is contained in an amount of 8.6 to 11.9% by weight relative to 100% by weight of the total of the polyester resin composition; the melamine cyanurate is contained in an amount of 3.8 to 5.2% by weight relative to 100% by weight of the total of the polyester resin composition; the phosphate ester is contained in an amount of 1.6 to 6.9% by weight relative to 100% by weight of the total of the polyester resin composition; The intrinsic viscosity of the polyethylene terephthalate resin is smaller than the intrinsic viscosity of the polybutylene terephthalate resin; The polyethylene terephthalate resin has a melting point of 243 to 256°C, The glass fiber is SiO 2 50-55% by weight, Al 2 O 3 15 to 21 wt. % of SiO2 and 13 to 19 wt. % of CaO; the glass fibers are glass fibers with a round or flat cross section; The aspect ratio of the glass fiber is 1:1 to 1:4, the aspect ratio being the ratio of length (L) to diameter (D) (L / D); The glass fibers have an average diameter of 10 to 13 μm and an average length of 2.5 to 6 mm. Polyester resin composition.

2. 2. The polyester resin composition according to claim 1, wherein the polybutylene terephthalate resin and the polyethylene terephthalate resin each have an intrinsic viscosity (η) of 0.7 to 0.9 dl / g.

3. 2. The polyester resin composition according to claim 1, wherein the polyethylene terephthalate resin is a recycled polyethylene terephthalate resin.

4. The polyester resin composition according to claim 3, wherein the recycled polyethylene terephthalate resin is a resin obtained by processing mineral water bottles.

5. The polyester resin composition according to claim 1 , further comprising an anti-dripping agent, an antioxidant, a polyethylene-based lubricant, and a hydrolysis inhibitor.

6. 2. The polyester resin composition according to claim 1, wherein the polyester resin composition has a high-load heat distortion temperature of 190°C or higher as measured under 1.82 MPa in accordance with ISO 75, a flexural strength of 180 MPa or higher as measured on a 4.0 mm test piece using SPAN 64 in accordance with ISO 178 at a speed of 2 mm / min, and a flexural modulus of 8000 MPa or higher.

7. A method for producing a composite material, comprising the steps of kneading and extruding a material composition comprising polybutylene terephthalate resin, polyethylene terephthalate resin, glass fiber, aluminum salt of diethylphosphinic acid, melamine cyanurate, and a phosphoric acid ester; The polybutylene terephthalate resin is contained in an amount of 24 to 41.7% by weight based on 100% by weight of the total of the material composition; The polyethylene terephthalate resin is contained in an amount of 10 to 25% by weight based on 100% by weight of the total of the material composition; The glass fiber is contained in an amount of 20 to 40% by weight based on 100% by weight of the total of the material composition; The aluminum salt of diethylphosphinic acid is contained in an amount of 8.6 to 11.9 wt % relative to 100 wt % of the total of the material composition; The melamine cyanurate is contained in an amount of 3.8 to 5.2% by weight based on 100% by weight of the total material composition; The phosphate ester is contained in an amount of 1.6 to 6.9 wt % relative to 100 wt % of the total of the material composition; The intrinsic viscosity of the polyethylene terephthalate resin is smaller than the intrinsic viscosity of the polybutylene terephthalate resin; The polyethylene terephthalate resin has a melting point of 243 to 256°C, The glass fiber is SiO 2 50-55% by weight, Al 2 O 3 15 to 21 wt. % of SiO2 and 13 to 19 wt. % of CaO; the glass fibers are glass fibers with a round or flat cross section; The aspect ratio of the glass fiber is 1:1 to 1:4, the aspect ratio being the ratio of length (L) to diameter (D) (L / D); The glass fibers have an average diameter of 10 to 13 μm and an average length of 2.5 to 6 mm. A method for producing a polyester resin composition.

8. A molded article comprising the polyester resin composition according to any one of claims 1 to 6.

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