Thermoplastic polyester resin composition, molded product, and preparation method for thermoplastic polyester resin composition

Abstract

The present invention relates to a thermoplastic polyester resin composition having excellent flame retardancy and a preparation method therefor, and a molded product. The thermoplastic polyester resin composition at least comprises: a polyester (A) having a phosphorus-containing structure at a repeating unit and / or an end of a molecular chain, and a phosphorus-based flame retardant (B), wherein the polyester (A) is composed of a dicarboxylic acid and / or a derivative monomer unit thereof capable of forming an ester, a diol monomer unit having 4-10 carbon atoms, and a phosphorus-containing compound monomer unit capable of forming a carboxylate group.

Description

A thermoplastic polyester resin composition, a molded article, and a method for preparing the same. Technical Field

[0001] This invention relates to a thermoplastic polyester resin composition with excellent flame retardancy, a molded article thereof, and a method for preparing the same. Background Technology

[0002] Polybutylene terephthalate (PBT) resin is a polyester produced by the condensation polymerization of phthalic acid and 1,4-butanediol. It is a milky white, translucent to opaque, semi-crystalline thermoplastic polyester with excellent heat resistance, chemical resistance, electrical properties, mechanical properties, and moldability. Through modification with various additives or compounding with other resins, it is widely used in industrial fields such as electrical appliances, automobiles, aircraft manufacturing, communications, home appliances, and transportation. For example, PBT modified with glass fiber can be used to manufacture electronic components requiring high dimensional stability under long-term high-temperature conditions. PBT has a high breakdown voltage, making it suitable for manufacturing high-voltage resistant components. Due to its good flowability in the molten state, it is suitable for injection molding of complex electrical parts, such as integrated circuit sockets, printed circuit boards, computer keyboards, electrical switches, fuses, temperature control switches, and protectors. In the automotive industry, it is widely used in car bumpers, carburetors, spark plugs, fuel supply system components, and ignition devices. In the communications field, PBT is widely used in integrated modules for program-controlled telephones, junction boxes, and power tools.

[0003] However, PBT has poor flame retardant properties (UL94 HB rating), is easily combustible in air, difficult to char, drips easily during combustion, and releases large amounts of dense smoke and toxic gases, posing a significant hazard. Therefore, flame retardant modification is necessary. The flame retardants used for PBT flame modification are mainly halogenated flame retardants, with bromine-based flame retardants, such as DBDPE and brominated epoxy resins, being commonly used. These achieve excellent flame retardant effects through synergistic action with Sb₂O₃. While halogenated flame retardants offer excellent flame retardant effects, they generate large amounts of smoke and toxic corrosive gases during decomposition and combustion, causing "secondary disasters." Furthermore, the combustion products are halides with a long atmospheric lifetime, making them difficult to remove once in the atmosphere, severely polluting the atmospheric environment and damaging the ozone layer. Additionally, the combustion and pyrolysis products of polybrominated diphenyl ether flame-retardant polymers contain toxic polybrominated dibenzodioxanes (PBDD) and polybrominated dibenzofurans (PBDF). Currently, the application of halogenated flame retardants is facing increasing restrictions.

[0004] Phosphorus-based flame retardants are effective flame retardants with advantages such as low smoke, non-toxicity, and low / halogen-free properties, aligning with the development trend of flame retardants and finding increasingly widespread application in flame-retardant materials. However, compared to halogen-based flame retardants, phosphorus-based flame retardants have poorer flame-retardant effects. To achieve the same flame-retardant rating, large amounts of phosphorus-based flame retardants are often required, which significantly impacts the material's mechanical strength, toughness, heat resistance, and processability. Furthermore, as the amount of phosphorus-based flame retardant added increases, the material cost also rises significantly.

[0005] Patent document 1 (CN102532499A) discloses a flame-retardant polyester composite material containing both reactive phosphorus-based flame retardants and additive phosphorus-based flame retardants. The polymerization temperature is as high as 290°C and the time is as long as 90 minutes or more. The phosphorus compounds added during the polymerization process will undergo severe decomposition, resulting in the inability to obtain a high molecular weight polyester copolymer.

[0006] Patent Document 2 (Japanese Patent Application No. 4-337116A) discloses a copolyester resin obtained by copolymerization with a reactive flame retardant that can form phosphonate groups. However, the reactivity of phosphonic acid with alcohol is poor, and high molecular weight copolyester cannot be prepared under the polymerization conditions described in Patent Document 2.

[0007] Patent document 3 (WO2002 / 042374) discloses a halogen-free flame-retardant PBT copolymer resin prepared by adding a reactive phosphorus flame retardant. However, in order to achieve good flame retardant performance, a large amount of this reactive phosphorus flame retardant needs to be added, which will lead to a sharp decrease in the heat resistance and mechanical strength of the PBT copolymer resin.

[0008] Patent document 4 (CN113912993A) discloses a halogen-free flame-retardant PBT composite material that is free from mold scale and corrosion, and contains aluminum diethylphosphite, melamine cyanurate and phosphate flame retardants. However, in order to achieve the V0 flame retardant level, the amount of flame retardant compound added needs to be more than 15 parts by weight, which will lead to a decrease in mechanical properties and the generation of a large amount of phosphine gas that corrodes the metal.

[0009] Patent Document 1: CN102532499A

[0010] Patent Document 2: Japanese Patent Application No. 4-337116A

[0011] Patent Document 3: WO2002 / 042374

[0012] Patent Document 4: CN113912993A Summary of the Invention

[0013] In view of the above problems, the object of the present invention is to provide a thermoplastic polyester resin composition with high flame retardancy and good mechanical properties, a method for preparing the composition and a molded article thereof.

[0014] Through in-depth research, the inventors discovered that by introducing a copolyester containing specific phosphorus-containing monomers and a specific phosphorus-based flame retardant into the molecular chain and then melt-blending the resulting composition, the flame retardant performance can be improved while maintaining good mechanical properties, toughness, heat resistance, and processability, thus achieving the purpose of this invention, while significantly reducing the amount of flame retardant added.

[0015] That is, in order to achieve the above-mentioned objective, the present invention has the following configuration:

[0016] The thermoplastic polyester resin composition of the present invention comprises at least: a polyester (A) having a phosphorus-containing structure in repeating units and / or at the ends of the molecular chain and a phosphorus-based flame retardant (B), wherein the polyester (A) is composed of a dicarboxylic acid and / or its derivative monomer unit capable of forming an ester, a diol monomer unit having 4 to 10 carbon atoms, and a phosphorus-containing compound monomer unit capable of forming a carboxylic acid ester group.

[0017] In some embodiments, the dicarboxylic acid component (dicarboxylic acid and / or its ester-forming derivative monomer unit) used in the above-described polyester (A) comprises terephthalic acid and / or its ester-forming derivatives. Examples of ester-forming derivatives of terephthalic acid include, for example, alcohol ester derivatives such as dimethyl terephthalate or diethyl terephthalate; and other ester-forming derivatives such as terephthaloyl chloride. In addition, the dicarboxylic acid component of the present invention may also include one or more dicarboxylic acid components selected from the following and their ester-forming derivatives, specifically including, but not limited to, the following examples: isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 4,4'-dicarboxylated diphenylmethane, anthracene dicarboxylic acid, 4, Aromatic dicarboxylic acids such as 4'-diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, 4,4'-diphenyl etherdicarboxylic acid, 5-sulfoisophthalic acid, sodium monosodium 5-thioisophthalate, or sodium 3-sulfoisophthalate; alicyclic dicarboxylic acids such as 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, cyclopentanedicarboxylic acid, or 4,4'-dicyclohexyldicarboxylic acid; and aliphatic dicarboxylic acids such as oxalic acid, succinic acid, adipic acid, pimelic acid, octanoic acid, azelaic acid, sebacic acid, dodecyl diketo acid, or dimer acids. The corresponding alkyl diesters and diacyl chlorides of the above dicarboxylic acids can also be listed as monomer raw materials.

[0018] When the aforementioned "the dicarboxylic acid component used in the polyester (A) contained in the thermoplastic polyester resin composition includes terephthalic acid and / or its ester-forming derivatives" preferably, the content of monomer units from terephthalic acid and / or its ester-forming derivatives is 70 mol% or more, preferably 75 mol% or more, more preferably 80 mol% or more, and the upper limit of this content is preferably 100 mol% or less, relative to the total amount of monomer units from dicarboxylic acid and / or its ester-forming derivatives used as polyester resin raw materials. A higher content of monomer units from terephthalic acid and / or its ester-forming derivatives, for example, 80 mol% or more, improves the crystallinity of the polyester resin and enhances its mechanical properties. More preferably, it is 90 mol% or more, even more preferably 95 mol% or more, and the upper limit of this content is preferably 100 mol% or less.

[0019] Preferably, the monomer unit of the dicarboxylic acid and / or its ester-forming derivative is composed of one or more elements selected from carbon, hydrogen, oxygen, and nitrogen. When the monomer unit of the dicarboxylic acid and / or its ester-forming derivative is composed of only one or more elements selected from carbon, hydrogen, oxygen, and nitrogen, the polyester resin can be guaranteed to have good crystallinity and mechanical strength.

[0020] The diol component with 4 to 10 carbon atoms used in the above polyester (A) can be mainly 1,4-butanediol. In addition, the diol component in the polyester (A) of the composition of the present invention may also include one or more diols selected from the following examples, specifically including but not limited to: aliphatic diols such as 1,5-pentanediol, 1,6-hexanediol, or decanediol; alicyclic diols such as 1,1-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanediol, 1,4-dicyclohexanediol, or tricyclodecanediol; and aromatic diols such as benzenediethanol, bis(p-hydroxy)biphenyl, bis(p-hydroxy)diphenylpropane, 2,2-bis[4-(2-hydroxyethoxy)phenyl]propane, bis[4-(2-hydroxyethoxy)phenyl]sulfone, 1,1-bis[4-(2-hydroxyethoxy)phenyl]cyclohexane, 4,4-dihydroxy-p-terphenyl, or 4,4-dihydroxy-p-tetraphenyl. The aforementioned diols can also be used in the form of acetylated compounds or alkali metal salts.

[0021] "The diol component with 4 to 10 carbon atoms used in polyester (A) is mainly 1,4-butanediol" means that, relative to the total amount of diol monomer units used as raw materials for polyester resin, the content of 1,4-butanediol is 90 mol% or more, preferably 93 mol% or more, more preferably 95 mol% or more, and the upper limit of this content is preferably 100 mol% or less. When the content of 1,4-butanediol is within this range, the crystallinity of the thermoplastic polyester resin composition can be maintained, thereby maintaining high mechanical properties.

[0022] In some embodiments, the phosphorus-containing monomer in the polyester (A) that can form a carboxylic acid ester group is a phosphorus-containing compound containing 1 to 2 carboxyl or hydroxyl functional groups in its molecular structure. Specific examples include, but are not limited to, the following: [(6-oxo-6H-dibenzo[C,E][1,2]oxaphosphazenecyclo-6-yl)methyl]succinic acid, N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester, bis(4-carboxyphenyl)phenylphosphine oxide, [(6-oxobridge-6H-dibenzo[C,E][1,2]oxaphosphazenecyclo-6-yl)methyl]succinic acid bis(2-hydroxyethyl) ester, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, and other phosphorus-containing compounds containing two reactive groups, 9,10-dihydro-9 Phosphorus-containing compounds containing one reactive group, such as oxa-10-phosphaphenanthrene-10-ethanol-10-oxide, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-methanol-10-oxide, or 2,6,7-trioxa-1-phosphabicyclo(2.2.2)octane-4-methanol-1-oxide, are preferred. These include [(6-oxo-6H-dibenzo[C,E][1,2]oxaphosphahexane-6-yl)methyl]succinic acid, [(6-oxobridge-6H-dibenzo[C,E][1,2]oxaphosphahexane-6-yl)methyl]succinic acid bis(2-hydroxyethyl) ester, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-ethanol-10-oxide, N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester, or bis(4-carboxyphenyl)phenylphosphine oxide. Considering that phosphorus-containing compounds have good reactivity and flame retardant effects, it is more preferable to be at least one of the group consisting of [(6-oxo-6H-dibenzo[C,E][1,2]oxophosphoric acid hexane-6-yl)methyl]succinic acid, N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester and bis(4-carboxyphenyl)phenylphosphine oxide, and most preferably [(6-oxo-6H-dibenzo[C,E][1,2]oxophosphoric acid hexane-6-yl)methyl]succinic acid.

[0023] In some embodiments, the content of phosphorus-containing monomer units capable of forming carboxylic acid ester groups in the polyester (A) is less than 8 mol% relative to the total amount of the dicarboxylic acid and / or its derivative monomer units capable of forming esters. From a flame-retardant effect perspective, the lower limit of the content of phosphorus-containing monomer units capable of forming carboxylic acid ester groups is preferably 0.4 mol% or more, more preferably 0.8 mol% or more, and even more preferably 1.2 mol% or more. On the other hand, from the perspective of maintaining the crystallinity of the polyester resin and the heat resistance of the polyester, the upper limit of the content is more preferably 7 mol% or less, more preferably 6 mol% or less, and even more preferably 5 mol% or less.

[0024] In some embodiments, in the thermoplastic polyester composition of the present invention, the phosphorus-based flame retardant (B) is at least one selected from the group consisting of phosphite compounds, phosphonate compounds, phosphate compounds, alkyl hypophosphite compounds, phosphate compounds, and phosphorazene compounds. Specific examples include, but are not limited to, ammonium polyphosphate, ammonium polyphosphate, ammonium phosphate, triphenyl phosphate, tricresyl phosphate, propylbenzene phosphate, butylbenzene phosphate, toluene diphenyl phosphate, phosphite, dimethyl phosphite, distearate pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, diphenol isooctyl phosphite, aluminum hypophosphite, phenyl aluminum hypophosphite, diethyl aluminum hypophosphite, zinc hypophosphite, phenyl zinc hypophosphite, diethyl zinc hypophosphite, P,P-diphenyl-zinc hypophosphite, aluminum phosphate, polyaluminum phosphate, or tri-(ethylphosphite)aluminum. Considering that phosphorus-based flame retardants can have good flame retardant effects, the phosphorus-based flame retardant (B) is further preferably composed of at least an alkyl hypophosphite compound, and even more preferably composed of at least diethyl aluminum hypophosphite.

[0025] In some embodiments, the amount of the phosphorus-based flame retardant (B) added is less than 8 wt% relative to the total mass of the thermoplastic polyester resin composition. From the perspective of improving the flame retardancy of the thermoplastic polyester composition, the lower limit of the amount of the phosphorus-based flame retardant added is preferably 0.5 wt% or more, more preferably 0.9 wt% or more. On the other hand, from the perspective of maintaining the mechanical properties of the thermoplastic polyester composition, the upper limit of the amount of the phosphorus-based flame retardant (B) added is preferably 6.5 wt% or less, more preferably 5.5 wt% or less, and even more preferably 5 wt% or less.

[0026] In some embodiments, the weight ratio of phosphorus content (Pa) of polyester (A) to phosphorus content (Pb) of phosphorus-based flame retardant (B) in the thermoplastic polyester composition of the present invention, i.e., Pa / Pb, is 0.01 to 7.00. From the perspective of maintaining the flame retardancy of the thermoplastic polyester resin composition while suppressing the decline in its mechanical properties, the lower limit of Pa / Pb is preferably 0.05 or more, more preferably 0.10 or more, and even more preferably 0.20 or more. From the perspective of processing and molding performance, the upper limit of Pa / Pb is preferably less than 5.50, more preferably less than 4.00, and even more preferably less than 1.00. The phosphorus content (Pa) of polyester (A) is obtained by multiplying the weight ratio of phosphorus in the phosphorus-containing compound that can form carboxylic acid ester groups in polyester (A) by the weight of polyester (A) in the thermoplastic polyester composition. The phosphorus content (Pb) of phosphorus-based flame retardant (B) is obtained by multiplying the weight ratio of phosphorus in the phosphorus-based flame retardant (B) molecule by the weight of phosphorus-based flame retardant (B) in the thermoplastic polyester composition.

[0027] It is generally believed that the flame-retardant mechanism of polyester resin combined with phosphorus-based flame retardant (B) is that during combustion, the polyester resin and the flame retardant react to form a non-combustible carbonized layer, thus improving flame retardancy. However, in reality, the phosphorus-based flame retardant (B) in the polyester resin composition is incompatible and unevenly dispersed. Especially under conditions of high shear on the surface of molded products, such as injection molding, the phosphorus-based flame retardant escapes the surface layer and condenses into the interior of the molded product. As a result, the concentration of the flame retardant component on the surface of the molded product becomes smaller, making it difficult to achieve the purpose of improving flame retardancy by forming a carbonized layer on the surface. Therefore, in order to achieve a flame-retardant effect, a larger amount of flame retardant must be added, leading to a decrease in the mechanical properties of the resulting resin composition, especially in terms of tensile elongation at break and impact resistance.

[0028] In addition, when phosphorus-containing compound monomer units that can form carboxylic acid ester groups are introduced into polyester (A) as flame retardant components, although they can be uniformly dispersed at the molecular level, their concentration must reach a certain amount in order to obtain a high flame retardant effect. This will lead to a decrease in the crystallinity of polyester (A) and make it difficult to demold and mold.

[0029] Therefore, in the above polyester (A), phosphorus-containing compound monomer units that can form carboxylic acid ester groups are added in a specific amount, and the phosphorus-based flame retardant (B) is adjusted to the above specific range. This can control the total amount of flame retardant components, and at the same time, the flame retardant components in the molded product have good dispersion uniformity, resulting in high flame retardancy while significantly suppressing the low mechanical properties.

[0030] For the thermoplastic polyester resin composition of the present invention, when it is melted at a temperature 25°C higher than its melting point and then hot-pressed into a 1.6 mm thick sample strip, and the sample strip is subjected to a vertical burning test, its flame retardancy rating is preferably UL-94V-0. Specifically, the flame retardancy test is conducted according to the UL 94-2013 flammability standard, and the standard strip sample dimensions are 125±5 mm in length, 13±0.5 mm in width, and 1.6±0.15 mm in thickness. The sample strip can be obtained by hot pressing, cutting, injection molding, etc., as long as the density is consistent.

[0031] From the perspective of the heat resistance of the thermoplastic polyester resin composition, the melting point (Tm) of the above-mentioned thermoplastic polyester resin composition is preferably 200°C or higher, more preferably 205°C or higher, and even more preferably 210°C or higher. From the perspective of the processing performance and mechanical properties of the thermoplastic polyester composition, the crystallization temperature (Tmc) of the thermoplastic polyester resin composition is preferably 170°C or higher, more preferably 175°C or higher, and even more preferably 180°C or higher. The melting point (Tm) and crystallization temperature (Tmc) of the thermoplastic polyester composition can be determined by the following method: Under a nitrogen atmosphere, the obtained thermoplastic polyester resin composition is heated from 30°C to 250°C at a heating rate of 20°C / min until it reaches a fully molten state, and held at this temperature for 2 minutes. Then, using a differential scanning calorimeter, the thermoplastic polyester resin composition is cooled from the molten state to 30°C at a cooling rate of 20°C / min, and held at this temperature for 2 minutes. The temperature at the top of the exothermic peak during crystallization is the crystallization temperature (Tmc) of the thermoplastic polyester resin composition. Then, the temperature is increased to 250°C at a heating rate of 20°C / min, and the temperature at the top of the endothermic peak during the heating process is measured; this temperature is the melting point (Tm) of the thermoplastic polyester resin composition.

[0032] In this invention, considering the need to further ensure the mechanical properties required for actual use, the number-average molecular weight (Mn) of the polyester (A) is preferably 8000 or more, and more preferably 20000 or less. Further, the lower limit of the number-average molecular weight is more preferably 9000 or more, and even more preferably 10000 or more. On the other hand, considering melt molding processing, the upper limit of the number-average molecular weight is more preferably 18000 or less, and even more preferably 16000 or less. The number-average molecular weight of the polyester (A) is a value obtained by gel permeation chromatography using hexafluoroisopropanol as a solvent and then converted using polymethyl methacrylate (PMMA) as a standard sample.

[0033] The polyester (A) contained in the thermoplastic polyester resin composition of the present invention can be prepared by the following method: esterification or transesterification is carried out on the diol monomer having 4 to 10 carbon atoms and the dicarboxylic acid and / or its derivative monomer capable of forming esters in the range of 150-250°C under normal pressure and / or reduced pressure. After the esterification or transesterification is completed, the phosphorus-containing compound capable of forming carboxylic acid ester groups is added to the system, and then a condensation reaction is carried out at 240-270°C and a pressure below 500 Pa to obtain polyester (A) having a phosphorus-containing structure in the repeating unit and / or at the end of the molecular chain.

[0034] To ensure a good polymerization rate and obtain a high molecular weight polymer, the molar ratio of the diol monomer to the dicarboxylic acid and / or its ester-forming derivative monomers is preferably 1.05-2.50. To obtain a high molecular weight polymer while avoiding polymer degradation due to prolonged reaction, the total reaction time is preferably 3-6.5 hours. To control the polymer molecular weight within a suitable range, the polycondensation reaction is preferably stopped after the stirrer torque reaches the target value of 1.6-5 kg-cm. To maximize the reaction rate of the phosphorus compound and prevent its decomposition due to prolonged heating, a phosphorus-containing monomer capable of forming carboxylic acid ester groups is preferably added in the later stages of the esterification or transesterification reaction or the early stages of the condensation reaction. To obtain a polyester (A) with a high degree of polymerization, the reaction temperature for the condensation reaction at 240-270°C and a pressure below 500 Pa is further preferably 245°C or higher, and even more preferably 248°C or higher. On the other hand, in order to suppress thermal decomposition, the reaction temperature of the condensation reaction is further preferably below 265°C, and even more preferably below 260°C.

[0035] In some embodiments, the thermoplastic polyester resin composition of the present invention is prepared by melting and compounding a certain weight of the above-mentioned polyester (A) and a certain weight of phosphorus-based flame retardant (B). Other additives, such as fillers listed below, may be added as needed. The melt compounding step includes, but is not limited to, preparation using existing melt compounding machines such as single-screw or twin-screw extruders, Banbury mixers, and compounding mills. For example, when using a closed compounding mill, a certain weight of the above-mentioned phosphorus-containing structural polyester (A) and a certain weight of phosphorus-based flame retardant (B) are added to the closed compounding mill, and then compounded at 235°C to 270°C for 3 to 10 minutes to prepare the thermoplastic polyester resin composition. To ensure uniform compounding of the components in the thermoplastic polyester composition, the compounding temperature is preferably 240°C or higher, more preferably 245°C or higher, and the compounding time is preferably 3.5 minutes or higher, more preferably 4.5 minutes or higher. On the other hand, in order to suppress thermal decomposition, the mixing temperature is preferably below 265°C, more preferably below 260°C, and the mixing time is preferably below 7 minutes, more preferably below 6 minutes.

[0036] In some embodiments, the phosphorus-containing monomers used in the preparation method of the polyester (A) of the present invention that can form carboxylic acid ester groups are phosphorus-containing compounds containing 1 to 2 carboxyl or hydroxyl functional groups in their molecular structure. Specific examples include, but are not limited to, the following: [(6-oxo-6H-dibenzo[C,E][1,2]oxaphosphazenecyclo-6-yl)methyl]succinic acid, N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester, bis(4-carboxyphenyl)phenylphosphine oxide, [(6-oxobridge-6H-dibenzo[C,E][1,2]oxaphosphazenecyclo-6-yl)methyl]succinic acid bis(2-hydroxyethyl) ester, 10-(2,5-dihydroxy... Phosphorus-containing compounds containing two reactive groups, such as (-10H-9-oxa-10-phosphaphenanthrene-10-oxide), and phosphorus-containing compounds containing one reactive group, such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-ethanol 10-oxide, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-methanol 10-oxide, or 2,6,7-trioxa-1-phosphabicyclo(2.2.2)octane-4-methanol-1-oxide. Preferably, the compounds are [(6-oxo-6H-dibenzo[C,E][1,2]oxaphosphazenecyclo-6-yl)methyl]succinic acid, [(6-oxo-6H-dibenzo[C,E][1,2]oxaphosphazenecyclo-6-yl)methyl]succinic acid bis(2-hydroxyethyl) ester, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-ethanol 10-oxide, N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester, or bis(4-carboxyphenyl)phenylphosphine oxide. Considering the good reactivity and flame retardant effect of phosphorus-containing compounds, at least one of the following groups is preferred: [(6-oxo-6H-dibenzo[C,E][1,2]oxaphosphazenecyclo-6-yl)methyl]succinic acid, N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester, and bis(4-carboxyphenyl)phenylphosphine oxide. The most preferred is [(6-oxo-6H-dibenzo[C,E][1,2]oxophosphazenecyclo-6-yl)methyl]succinic acid.

[0037] The content of phosphorus-containing compound monomers capable of forming carboxylic acid ester groups is preferably less than 8 mol relative to the total amount of the dicarboxylic acid and / or its derivative monomers that can form esters.

[0038] In some embodiments, the phosphorus-based flame retardant (B) used in the preparation method of the thermoplastic polyester resin composition of the present invention is at least one selected from the group consisting of phosphite compounds, phosphonate compounds, phosphate compounds, alkyl hypophosphite compounds, phosphate compounds and phosphorazine compounds. Specific examples include, but are not limited to, ammonium polyphosphate, ammonium polyphosphate, ammonium phosphate, triphenyl phosphate, tricresyl phosphate, propylbenzene phosphate, butylbenzene phosphate, toluene diphenyl phosphate, phosphite, dimethyl phosphite, distearate pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, diphenol isooctyl phosphite, aluminum hypophosphite, phenyl aluminum hypophosphite, diethyl aluminum hypophosphite, zinc hypophosphite, phenyl zinc hypophosphite, diethyl zinc hypophosphite, P,P-diphenyl-zinc hypophosphite, aluminum phosphate, polyaluminum phosphate, or tri-(ethyl phosphite)aluminum. Considering the good flame retardancy of the thermoplastic polyester resin composition, alkyl hypophosphite compounds are more preferably preferred, and even more preferably, at least diethyl aluminum hypophosphite is included.

[0039] The amount of the phosphorus-based flame retardant (B) added is preferably less than 8 wt% relative to the total mass of the thermoplastic polyester resin composition.

[0040] In some embodiments, in the above-described method for preparing the thermoplastic polyester resin composition, the weight ratio of the phosphorus content (Pa) of the polyester (A) to the phosphorus content (Pb) of the phosphorus-based flame retardant (B), i.e., Pa / Pb, is 0.01 to 7.00.

[0041] Preferably, the thermoplastic polyester resin composition of the present invention may further include filler materials. Examples of filler materials include, but are not limited to, the following: fibrous inorganic or organic filler materials such as glass fiber, carbon fiber, potassium titanate whiskers, zinc oxide whiskers, aluminum borate whiskers, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, gypsum fiber, or metal fiber; and non-fibrous inorganic filler materials such as wollastonite, zeolite, sericite, kaolin, mica, talc, clay, pyrophyllite, bentonite, montmorillonite, asbestos, silicates, alumina, silicon oxide, magnesium oxide, zirconium oxide, titanium oxide, iron oxide, calcium carbonate, magnesium carbonate, dolomite, calcium sulfate, barium sulfate, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, glass microspheres, ceramic microspheres, boron nitride, silicon carbide, or silicon dioxide. The above filler materials may be hollow. Furthermore, the above filler materials may also be treated with coupling agents such as isocyanate compounds, organosilane compounds, organotitanate compounds, organoborane compounds, or epoxy compounds. The aforementioned montmorillonite can also be organo-modified montmorillonite obtained by cation exchange of interlaminar ions through organic ammonium salts. Considering improving the mechanical properties of the thermoplastic polyester resin composition and reducing its molding shrinkage, the aforementioned filler material is preferably a fibrous inorganic filler material, more preferably glass fiber or carbon fiber. The cross-sectional shape of the fibrous filler material is not particularly limited and can be circular or flat. Furthermore, the aforementioned filler material can be added alone or in combination of two or more types.

[0042] In the thermoplastic polyester resin composition, the amount of filler added is preferably 0.1-150 parts by weight relative to 100 parts by weight of the thermoplastic resin composition. Considering that the thermoplastic resin composition can possess good mechanical strength, the lower limit of the amount of filler added is further preferably 10 parts by weight or more, and even more preferably 30 parts by weight or more. On the other hand, the upper limit of the amount of filler added is preferably 100 parts by weight or less, and even more preferably 80 parts by weight or less.

[0043] The thermoplastic polyester resin composition of the present invention may also contain additives such as stabilizers, nucleating agents, antioxidants, release agents or color masterbatches.

[0044] The stabilizers may include phosphoric acid, trimethyl phosphate, triethyl phosphate, triethyl phosphonoacetate, 3,9-bis(2,6-di-tert-butyl-4-methylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane or tetra(2,4-di-tert-butyl-5-methylphenyl)[1,1-biphenyl]-4,4'-dimethylbisphosphonate, etc.

[0045] The nucleating agent may be one or more of inorganic or organic crystal nucleating agents. Examples of inorganic crystal nucleating agents include silicon dioxide, alumina, zirconium oxide, titanium dioxide, wollastonite, kaolin, talc, mica, or silicon carbide.

[0046] In addition, examples of organic crystal nucleating agents include aliphatic carboxylic acid amides, carboxylic acid metal salts, or sorbitol derivatives. Among the aliphatic carboxylic acid amides mentioned, examples include aliphatic monocarboxylic acid amides such as lauryl amide, palmitamide, oleamide, stearamide, erucamide, behenamide, ricinoleamide, or hydroxystearamide; N-substituted aliphatic monocarboxylic acid amides such as N-oleyl palmitamide, N-oleyl oleamide, N-oleyl stearamide, N-stearyl oleamide, N-stearyl stearamide, N-stearyl erucamide, N-hydroxymethylstearamide, or N-hydroxymethyl behenamide; and methylene bis-stearamide, ethylene bis-laurate amide, ethylene bis-decanoate amide, ethylene bis-oleamide, ethylene bis-stearamide, ethylene bis-erucamide, ethylene bis-behenamide, ethylene bis-isostearamide, ethylene bis-hydroxystearamide, butylene bis-stearamide, hexamethylene bis-oleamide, hexamethylene bis-di-oleamide, hexamethylene bis-di-iso-stearamide, ethylene bis-hydroxystearamide, butylene bis-stearamide, hexamethylene bis-oleamide, hexamethylene bis-di-iso-stearamide, hexamethylene bis-iso-stearamide, hexamethylene bis-hydroxystearamide, hexamethylene bis-oleamide, hexamethylene bis-iso-stear ... Aliphatic dicarboxylic acid amides such as stearamide, hexamethylene di-stearate amide, hexamethylene dihydroxystearamide, isophthalic acid bis-stearamide, or isophthalic acid di-12-hydroxystearamide; N,N'-dioleenyl sebacate amide, N,N'-dioleenyl adipamide, N,N'-distearate adipamide, N,N'-distearate sebacate amide, N,N'-distearate isophthalic acid amide N-substituted aliphatic carboxylic acid diamides such as amines or N,N'-distearate terephthalamides; N-substituted ureas such as N-butyl-N'-stearylurea, N-propyl-N'-stearylurea, N-stearyl-N'-stearylurea, N-phenyl-N'-stearylurea, xylene-bistearate urea, toluene-bistearate urea, hexamethylene-bistearate urea, diphenylmethane-bistearate urea, or diphenylmethane-bislaurylurea.

[0047] Examples of the metal salts of the carboxylic acids include sodium benzoate, potassium benzoate, lithium benzoate, calcium benzoate, magnesium benzoate, barium benzoate, lithium terephthalate, sodium terephthalate, potassium terephthalate, calcium oxalate, sodium laurate, potassium laurate, sodium myristate, potassium myristate, calcium myristate, sodium octadecylate, calcium octadecylate, sodium stearate, potassium stearate, lithium stearate, calcium stearate, magnesium stearate, barium stearate, sodium lignite, calcium lignite, sodium benzoate, sodium salicylate, potassium salicylate, zinc salicylate, aluminum dibenzoate, potassium dibenzoate, lithium dibenzoate, sodium naphthalenedicarboxylate, or sodium cyclohexanecarboxylate.

[0048] Examples of sorbitol derivatives include bis(benzyl)sorbitol, bis(p-methylbenzyl)sorbitol, bis(p-ethylbenzyl)sorbitol, bis(p-chlorobenzyl)sorbitol, bis(p-bromobenzyl)sorbitol, or sorbitol derivatives obtained by further chemical modification of the above-mentioned sorbitol derivatives.

[0049] Considering the effect of promoting crystallization of the thermoplastic polyester resin composition, the nucleating agent is preferably silica, wollastonite, kaolin, talc, mica, or aliphatic carboxylic amide. Furthermore, in the thermoplastic polyester resin composition of the present invention, the content of the nucleating agent is preferably 0.05 to 5 parts by weight relative to 100 parts by weight of polyester (A). When the content of the nucleating agent is within this range, the crystallization-promoting effect can be maintained, resulting in a thermoplastic polyester resin composition with excellent toughness. Further, the lower limit of the content of the nucleating agent is more preferably 0.1 parts by weight or more, and the upper limit is more preferably 3 parts by weight or less, and even more preferably 2 parts by weight or less.

[0050] The antioxidant is preferably at least one of phenolic antioxidants or sulfur-based antioxidants. Since combining two or more types of antioxidants produces a synergistic effect, it is preferable to use both phenolic and sulfur-based antioxidants to obtain better heat resistance and thermal stability.

[0051] Examples of phenolic antioxidants include 2,4-dimethyl-6-tert-butylphenol, 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-4-ethylphenol, 4,4'-butylidene bis(6-tert-butyl-3-methylphenol), 2,2'-methylene bis(4-methyl-6-tert-butylphenol), and 2,2'-methylene bis(4-ethyl-6-tert-butylphenol). Phenol), octadecyl-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate, pentaerythritol tetratetra[3-(3,5-di-tert-butyl-4-hydroxyphenyl)]propionate, 1,1,3-tris(2-methyl-4-hydroxy-5-di-tert-butylphenyl)butane, tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, triethylene glycol bis[3-(3-tert-butyl-4-hydroxy-5- [Methylphenyl)propionate], 1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,4-bis(n-octylthio)-6-(4-hydroxy-3,5-di-tert-butylaniline)-1,3,5-triazine, 2,2-thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexamethylenebis(3,5-di-tert-butyl- 4-Hydroxyhydrocinnamamide), diethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 2,4-bis[(octylthio)methyl]o-cresol, or isooctyl-3-(3,5-di-tert-butyl-4-hydroxybenzyl)propionate, etc.

[0052] Examples of sulfur-based antioxidants include dilauryl thiodipropionate, dimyristyl thiodipropionate, distearate thiodipropionate, di(tetrazyl) thiodipropionate, pentaerythritol (3-lauryl thiopropionate), or 2-mercaptobenzimidazole.

[0053] In the polyester resin composition of the present invention, the total content of the antioxidant is preferably 0.01-3 parts by weight relative to 100 parts by weight of polyester (A). Within this range, the antioxidant effect can be maintained, while the generation of gas during melt processing can be suppressed. Further, the lower limit of the antioxidant content is more preferably 0.05 parts by weight or more, and more preferably 0.1 parts by weight or more. In addition, the upper limit is more preferably 2 parts by weight or less, and more preferably 1 part by weight or less.

[0054] There are no particular limitations on the release agent used; any release agent commonly used for thermoplastic resins can be used. Specifically, examples include fatty acids, fatty acid metal salts, hydroxy fatty acids, fatty acid esters, aliphatic partially saponified esters, alkanes, low molecular weight polyolefins, fatty acid amides, alkylene difatty acid amides, aliphatic ketones, lower fatty acid alcohol esters, fatty acid polyol esters, fatty acid polydiol esters, or modified polysiloxanes, etc.

[0055] The fatty acid is preferably a fatty acid with 6 to 40 carbon atoms, specifically including oleic acid, lauric acid, stearic acid, hydroxystearic acid, docosanoic acid, arachidonic acid, linoleic acid, linolenic acid, ricinoleic acid, palmitic acid, stearic acid, limonene acid, or mixtures thereof.

[0056] The fatty acid metal salt is preferably an alkali metal salt or alkaline earth metal salt of fatty acid with 6 to 40 carbon atoms, specifically including calcium stearate, sodium lignite, or calcium lignite.

[0057] The hydroxy fatty acids mentioned can be listed as 1,2-hydroxy fatty acids, etc.

[0058] The fatty acid esters may include stearate, oleate, linoleate, linolenic acid ester, adipate, docosinate, arachidonic acid ester, lignite ester, isostearate, or esters of polymeric acids, etc.

[0059] Examples of aliphatic partially saponified esters include partially saponified esters of lignite acid.

[0060] The alkanes are preferably alkanes with 18 or more carbon atoms, and can be exemplified by liquid paraffin, natural paraffin, microcrystalline wax, or petrolatum.

[0061] The low molecular weight polyolefin is preferably a polyolefin with a weight average molecular weight of less than 5000, specifically including polyethylene wax, maleic acid modified polyethylene wax, oxidized polyethylene wax, chlorinated polyethylene wax, or polypropylene wax, etc.

[0062] The fatty acid amide is preferably a fatty acid amide with 6 or more carbon atoms, specifically oleamide, erucamide, or docosamide, etc.

[0063] The alkylene difatty acid amide is preferably an alkylene difatty acid amide with 6 or more carbon atoms, specifically including methylene bis-stearamide, ethylene bis-stearamide, or N,N-bis(2-hydroxyethyl)stearamide, etc.

[0064] The aliphatic ketones mentioned can be listed as higher aliphatic ketones, etc.

[0065] The lower fatty acid alcohol ester is preferably a lower fatty acid alcohol ester with 6 or more carbon atoms, specifically including ethyl stearate, butyl stearate, ethyl docosanoate, or rice wax, etc.

[0066] The fatty acid polyol esters may include glyceryl monostearate, pentaerythritol monostearate, pentaerythritol tetrastearate, pentaerythritol adipate stearate, dipentaerythritol adipate stearate, or sorbitan monostearate, etc.

[0067] The fatty acid polydiol esters may be listed as polyethylene glycol fatty acid esters or polypropylene glycol fatty acid esters.

[0068] The modified polysiloxanes may include methylstyrene-modified polysiloxanes, polyether-modified polysiloxanes, higher fatty acid alkoxy-modified polysiloxanes, polysiloxanes containing higher fatty acids, higher fatty acid ester-modified polysiloxanes, methacrylic acid-modified polysiloxanes, or fluorinated polysiloxanes, etc.

[0069] The thermoplastic polyester resin composition of the present invention, the thermoplastic polyester resin composition material containing the present invention, or polyester (A) can be molded into the desired shape by any molding method such as injection molding, extrusion molding, blow molding, vacuum molding, or film molding. Since the flame retardant components can be uniformly dispersed during high-shear processing of the molded article surface, and it possesses excellent flame retardancy and mechanical properties, it is particularly suitable for injection molding.

[0070] Molded articles made from materials containing the thermoplastic polyester resin composition of the present invention or the thermoplastic polyester resin composition containing polyester (A) of the present invention can be used as mechanical structural parts, electronic and electrical parts, and automotive parts due to their good mechanical properties and heat resistance. Because the molded articles of the present invention have excellent flame retardancy, they can be used particularly in parts requiring high flame retardancy.

[0071] Materials containing the polyester (A) of this invention can be used as electronic and electrical insulating components, etc. These electronic and electrical insulating components can be categorized as: electronic and electrical housings, electrical equipment, and components. When the material containing polyester (A) is used as an insulating resin material for electrical housings, it possesses both processability and thermal stability properties while meeting the international flame retardant standard UL94 V; that is, it simultaneously satisfies flame retardancy, mechanical properties, and electrical properties. The polyester (A) is composed of aromatic dicarboxylic acids and / or their ester-forming derivative monomer units, diol monomer units with 4 to 10 carbon atoms, and phosphorus-containing compound monomer units capable of forming carboxylic acid ester groups.

[0072] Specific examples of electronic and electrical products containing the aforementioned electronic and electrical insulating components include: circuit breakers, electromagnetic switches, focusing boxes, flyback transformers, copiers, printing presses, general household appliances, OA machines, and other protective housing components; variable capacitors, various terminal blocks, converters, printed circuit boards, protective housing components, terminal blocks, coil frames, connectors, relays, disk drive brackets, transformers, switch components, socket components, motor components, sockets, plugs, condensers, various housings, resistors, metal terminals, and wire assemblies; computer-related components, audio components, lighting components, telecommunications equipment-related components, telephone equipment-related components, air conditioning components, VTRs, televisions, and other household appliance components; copier components, fax components, optical instrument components, automotive ignition device components, automotive connectors, or various automotive electrical components. Detailed Implementation

[0073] The present invention will be specifically described below through examples, but the present invention is not limited thereto.

[0074] The various properties of the thermoplastic polyester resin compositions obtained in the examples and comparative examples were determined by the following methods.

[0075] (1) Melting point (Tm) and crystallization temperature (Tmc)

[0076] Using a TA DSC-discover250 analytical instrument, 5 mg of the thermoplastic polyester resin composition sample prepared in the examples or comparative examples was accurately weighed and tested under the following conditions. Under a nitrogen atmosphere, the obtained thermoplastic polyester resin composition was heated from 30°C to 250°C at a heating rate of 20°C / min until it reached a fully molten state, and held at this temperature for 2 minutes. Then, using a differential scanning calorimeter, the thermoplastic polyester resin composition was cooled from the molten state to 30°C at a cooling rate of 20°C / min, and held at this temperature for 2 minutes. The temperature at the tip of the exothermic peak during this cooling process is the crystallization temperature Tmc of the thermoplastic polyester resin composition. Then, the temperature was increased to 250°C at a heating rate of 20°C / min (Comparative Example 8: heated to 280°C), and the tip temperature of the endothermic peak during this heating process was determined as the melting point Tm.

[0077] (2) Flame retardancy

[0078] Flame retardancy testing was conducted using UL 94-2013 standard. Each set of examples or comparative examples was repeated 5 times, and the average value was taken. The standard strip sample dimensions were 125±5 mm in length, 13±0.5 mm in width, and 1.6±0.15 mm in thickness. The specific method is as follows: The thermoplastic polyester resin composition obtained in the examples or comparative examples was melted in a hot press at 25°C above its melting point for 3 minutes, and then hot-pressed into a film with a thickness of 1.6 mm. The film sample was then rapidly cooled in ice water, and then cut into strips of the required standard sample size.

[0079] Evaluation results: Flame retardancy was determined based on the order "V-0 > V-1 > V-2 > combustible".

[0080] (3) Mechanical properties

[0081] Bending strength and bending fracture stroke: These were tested using bending tests. Each example or comparative example was repeated 5 times, and the average value was taken. The specific method was as follows: The thermoplastic polyester resin composition prepared in the examples or comparative examples was melted at a temperature 25°C above its melting point for 3 minutes, and then hot-pressed into a film with a thickness of 1.6 mm. The film sample was then rapidly cooled in ice water. The prepared film sample was cut into a sample piece with a length of 55 mm and a width of 13 mm. The sample piece was then treated in a forced-air drying oven at 130°C for 3 hours. Then, a three-point bending test was performed on a Shimadzu AGS-X-10KN device. The specific test conditions were: support point spacing of 20 mm and bending speed of 8 mm / min.

[0082] Impact strength: Tested using the IZOD cantilever beam impact test. Each example or comparative example was repeated 5 times, and the average value was taken. The specific method is as follows: The thermoplastic polyester resin composition prepared in the examples or comparative examples was melted at a temperature 25°C above its melting point for 3 minutes, then hot-pressed into a 1.6 mm thick film sample, and then rapidly cooled in ice water. The prepared film sample was cut into a sample piece with a length of 45 mm × width of 13 mm and a notch width of 0.49 mm × depth of 22 mm. The sample piece was then treated in a 130°C forced-air oven for 3 hours, and then subjected to the IZOD cantilever beam impact test (hammer: 2.75 J) on Yasuda Seiki's No. 258 equipment.

[0083] (4) Number-average molecular weight (Mn)

[0084] 2.5 mg of the thermoplastic polyester resin composition prepared in each example or comparative example was dissolved in 4 ml of hexafluoroisopropanol containing 0.0075 molar equivalents of sodium trifluoroacetate. After filtration through a filter with a pore size of 0.45 μm, the number-average molecular weight Mn was determined by GPC under the following conditions:

[0085] Pump: e-Alliance GPC system (Waters manufacture)

[0086] Detector: Differential detector, Waters 2414 (manufactured by Waters)

[0087] Column: Shodex HFIP-806M (2 columns) + HFIP-LG

[0088] Solvent: Hexafluoroisopropanol (with 0.0075N sodium trifluoroacetate added)

[0089] Flow rate: 0.5 ml / min

[0090] Sample injection volume: 0.1 ml

[0091] Temperature: 40℃

[0092] Molecular weight correction: polymethyl methacrylate.

[0093] (5) Processability:

[0094] When thermoplastic polyester resin compositions with a crystallization temperature of 170°C or higher prepared in the examples or comparative examples are injection molded, their processability is determined based on the demolding properties during injection molding and the warpage of the molded product. The processability of thermoplastic polyester resin compositions with a crystallization temperature below 170°C is directly determined as ×.

[0095] 〇: Easy demolding during injection molding, and suppression of warpage of the molded product;

[0096] ×: It is difficult to demold during injection molding, and the molded product warps significantly.

[0097] The raw materials used in the examples and comparative examples are as follows:

[0098] (1) Dicarboxylic acids:

[0099] Terephthalic acid (TPA): Mitsui Chemicals Co., Ltd.

[0100] IPA (Isophthalic Acid): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0101] 2,6-Naphthalenedicarboxylic acid (NPA): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0102] (2) Alcohols:

[0103] 1,4-Butanediol (BDO): Mitsubishi Chemical Corporation

[0104] 1,6-Hexanediol: Shanghai Aladdin Biochemical Technology Co., Ltd.

[0105] 1,3-Butanediol: Shanghai Aladdin Biochemical Technology Co., Ltd.

[0106] Ethylene glycol (EG): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0107] Pentaerythritol (PER): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0108] (3) Phosphorus-containing compounds that can form carboxylic acid ester groups:

[0109] [(6-oxo-6H-dibenzo[C,E][1,2]oxophosphazenehexane-6-yl)methyl]succinic acid (DDP): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0110] N,N-bis(2-hydroxyethyl)aminomethylenephosphonate diethyl ester (FRC-6): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0111] Bis(4-carboxyphenyl)phenylphosphine oxide (BCPPO): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0112] Diethyl hydroxymethylphosphonate (DEPM): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0113] (4) Phosphorus-containing compounds that cannot form carboxylic acid ester groups:

[0114] Dimethyl methylphosphonate (DMP): TISA (Shanghai) Chemical Industry Development Co., Ltd.

[0115] Sodium methylphosphonate (MPA_Na): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0116] (5) Phosphorus-based flame retardants:

[0117] Diethylaluminum hypophosphite (ADEP): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0118] Ammonium polyphosphate (APP): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0119] Triphenyl phosphate (TPP): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0120] Diethyl ethylphosphonate (DEEP): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0121] Hexaphenoxycyclotriphosphazene (HPCTP): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0122] (6) Non-phosphorus flame retardants:

[0123] Melamine cyanurate (MCA): Shanghai Aladdin Biochemical Technology Co., Ltd.

[0124] Aluminum hydroxide: Shanghai Aladdin Biochemical Technology Co., Ltd.

[0125] (7) Catalysts and other additives:

[0126] Tetrabutyl titanate (TBT): TCI (Shanghai) Chemical Industry Development Co., Ltd.

[0127] Pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid] (IR1010): TCI (Shanghai) Chemical Industry Development Co., Ltd.

[0128] Example 1

[0129] 0.45 mol of terephthalic acid (TPA, 74.76 g), 0.81 mol of 1,4-butanediol (BDO, 73.00 g), titanium compound catalyst TBT (addition amount: 0.05 wt% relative to the theoretical polyester mass), and antioxidant IR1010 (addition amount: 0.019 wt% relative to the theoretical polyester mass) were added to a 250 ml four-necked flask reactor equipped with a distillation column. Nitrogen gas was introduced and stirring was started. After rapidly heating to 100 °C, the esterification reaction was started under normal pressure while the temperature was slowly increased to a final temperature of 238 °C. The total esterification reaction time was 5 h. The reaction was then terminated and the oligomer melt was poured out.

[0130] The obtained oligomer melt, titanium compound catalyst TBT (addition amount: 0.015 wt% relative to the theoretical polyester mass), antioxidant IR1010 (addition amount: 0.031 wt% relative to the theoretical polyester mass), and phosphorus compound DDP (0.4 mol% relative to the total molar of TPA) were added to a dedicated polycondensation reaction tube. The reaction tube was then placed in an oil bath at 250°C and the polycondensation reaction was carried out under conditions below 300 Pa. The reaction was stopped when the torque of the stirrer reached the target value of 2.3 kg-cm, and the resulting product was a polyester with phosphorus-containing structures in the repeating units and / or ends of the molecular chain.

[0131] Weigh 46.15 g of the polyester obtained above, and weigh 3.85 g of aluminum diethylphosphite (7.7 wt% relative to the mass of the thermoplastic polyester resin composition). Add the weighed polyester and aluminum diethylphosphite to a test internal mixer and mix at 250°C for 5 min to obtain the thermoplastic polyester resin composition. The results are shown in Table 1. The theoretical polyester mass mentioned above is the theoretical polyester mass obtained by multiplying the molar amount of the aromatic dicarboxylic acid by the relative molar mass of the repeating unit of polyester (A).

[0132] Example 2

[0133] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 0.8 mol%, and the amount of ADEP added as flame retardant (B) during compounding was 5.3 wt%. The results are shown in Table 1.

[0134] Example 3

[0135] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 1.5 mol%, and the amount of ADEP added as flame retardant (B) during compounding was 3.5 wt%. The results are shown in Table 1.

[0136] Example 4

[0137] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 1.5 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 1.

[0138] Example 5

[0139] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 2.3 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 1.

[0140] Example 6

[0141] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 2.3 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 3.5 wt%. The results are shown in Table 1.

[0142] Example 7

[0143] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 2.3 mol%, and the amount of ADEP added as flame retardant (B) during compounding was 4.5 wt%. The results are shown in Table 1.

[0144] Example 8

[0145] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 2.3 mol%, and the amount of ADEP added as flame retardant (B) during compounding was 6.1 wt%. The results are shown in Table 1.

[0146] Example 9

[0147] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the amount of ADEP added as flame retardant (B) during compounding was 2.2 wt%. The results are shown in Table 1.

[0148] Example 10

[0149] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 1.6 wt%. The results are shown in Table 1.

[0150] Example 11

[0151] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 5.0 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 0.9 wt%. The results are shown in Table 1.

[0152] Example 12

[0153] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 6.5 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 0.9 wt%. The results are shown in Table 1.

[0154] Example 13

[0155] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 7.8 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 0.9 wt%. The results are shown in Table 1.

[0156] Example 14

[0157] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the amount of ADEP added as flame retardant (B) during compounding was 10.5 wt%. The results are shown in Table 1.

[0158] Comparative Example 1

[0159] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 8.5 mol%, and diethyl aluminum hypophosphite was not added during the mixing process. The results are shown in Table 1.

[0160] Comparative Example 2

[0161] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 5.0 mol%, and diethyl aluminum hypophosphite was not added during the mixing process. The results are shown in Table 1.

[0162] Example 15

[0163] Example 1 was repeated, except that the phosphorus compound was FRC-6, which was added at an amount of 3.0 mol%, and the amount of flame retardant (B) ADEP added during mixing was 2.2 wt%. The results are shown in Table 2.

[0164] Example 16

[0165] Example 1 was repeated, except that the phosphorus compound was BCPPO, which was added at an amount of 3.0 mol%, and ADEP, which was added as flame retardant (B) during mixing, was added at an amount of 2.2 wt%. The results are shown in Table 2.

[0166] Example 17

[0167] Example 1 was repeated, except that the phosphorus compound was DEPM, which was added at an amount of 1.3 mol%, and ADEP, which was added as flame retardant (B) during mixing, was added at an amount of 4.0 wt%. The results are shown in Table 2.

[0168] Comparative Example 3

[0169] Example 1 was repeated, except that the phosphorus compound was DMP, added at 3.0 mol%, and ADEP, added as flame retardant (B) during compounding, was added at 2.2 wt%. However, during the polycondensation reaction, the torque could not reach the target value. The polycondensation reaction was stopped after the torque reached its maximum value, and a polyester with phosphorus-containing structures in the repeating units and / or ends of the molecular chain was obtained. The results are shown in Table 2.

[0170] Comparative Example 4

[0171] Example 1 was repeated, except that the phosphorus compound was MPA_Na, added at 1.3 mol%, and ADEP, added as flame retardant (B) during compounding, was added at 4.0 wt%. However, during the polycondensation reaction, the torque could not reach the target value. The polycondensation reaction was stopped when the torque reached its maximum value, and a polyester with phosphorus-containing structures in the repeating units and / or ends of the molecular chain was obtained. The results are shown in Table 2.

[0172] Example 18

[0173] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the flame retardant (B) added during mixing was APP, with an addition amount of 5.3 wt%. The results are shown in Table 3.

[0174] Example 19

[0175] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the flame retardant (B) added during mixing was TPP, with an addition amount of 5.3 wt%. The results are shown in Table 3.

[0176] Example 20

[0177] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the flame retardant (B) added during mixing was DEEP, which was added at an amount of 5.3 wt%. The results are shown in Table 3.

[0178] Example 21

[0179] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the flame retardant (B) added during mixing was HPCTP, which was added at an amount of 5.3 wt%. The results are shown in Table 3.

[0180] Comparative Example 5

[0181] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the flame retardant (B) added during mixing was MCA, with an addition amount of 5.3 wt%. The results are shown in Table 3.

[0182] Comparative Example 6

[0183] Example 1 was repeated, except that the amount of phosphorus compound DDP added was 3.0 mol%, and the flame retardant (B) added during mixing was aluminum hydroxide, which was added at an amount of 5.3 wt%. The results are shown in Table 3.

[0184] Example 22

[0185] Example 1 was repeated, except that the dicarboxylic acid units were TPA (0.42 mol) and IPA (0.03 mol), the phosphorus compound DDP was added at 3.0 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 4.

[0186] Example 23

[0187] Example 1 was repeated, except that the dicarboxylic acid units were TPA (0.38 mol) and NPA (0.07 mol), the phosphorus compound DDP was added at 3.0 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 4.

[0188] Example 24

[0189] Example 1 was repeated, except that the dicarboxylic acid units were TPA (0.38 mol) and succinic acid (0.07 mol), the amount of phosphorus compound DDP was 3.0 mol, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 4.

[0190] Example 25

[0191] Example 1 was repeated, except that the diacid units were TPA (0.38 mol) and adipic acid (0.07 mol), the amount of phosphorus compound DDP was 3.0 mol, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 4.

[0192] Example 26

[0193] Example 1 was repeated, except that the diol units were BDO (0.78 mol) and 1,6-hexanediol (0.03 mol), the phosphorus compound DDP was added at 3.0 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 4.

[0194] Example 27

[0195] Example 1 was repeated, except that the diol units were BDO (0.68 mol) and 1,3-butanediol (0.13 mol), the phosphorus compound DDP was added at 3.0 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 4.

[0196] Comparative Example 7

[0197] Example 1 was repeated, except that the diol unit was EG (added at 0.54 mol), the phosphorus compound DDP was added at 3.0 mol%, and the final polymerization temperature was 290°C. ADEP, added as flame retardant (B) during compounding, was added at 2.2 wt%, and the compounding temperature was 310°C. The results are shown in Table 4.

[0198] Comparative Example 8

[0199] Example 1 was repeated, except that the diol units were BDO (0.68 mol) and pentaerythritol (0.13 mol), the phosphorus compound DDP was added at 3.0 mol%, and the amount of ADEP added as flame retardant (B) during mixing was 2.2 wt%. The results are shown in Table 4.

[0200] Table 1 Examples and Comparative Examples

[0201] Table 1 Subsequent

[0202] Table 1 Subsequent

[0203] Table 2 Examples and Comparative Examples

[0204] Table 3 Examples and Comparative Examples

[0205] Table 4 Examples and Comparative Examples

[0206] Table 1 shows that Examples 1-14 and Comparative Examples 1-2 illustrate that for polyester resin compositions, the flame retardancy rating of compositions prepared by blending a copolyester with a specific phosphorus-containing monomer introduced into the molecular chain and a specific phosphorus-based flame retardant reaches V-0. Compared with PBT blended with only a flame retardant or copolyester copolymerized with only a phosphorus-containing compound, the flame retardant effect is significantly improved. Compositions prepared by blending a phosphorus-containing polyester copolymer with less than 8 mol% phosphorus compound and less than 8 wt% phosphorus-based flame retardant not only improve flame retardancy but also achieve a higher molecular weight and excellent mechanical properties.

[0207] Table 2 shows that Examples 15-17 and Comparative Examples 3-4 illustrate that for phosphorus-containing polyester copolymers, high molecular weight can be prepared when PBT is copolymerized with phosphorus compounds that can form carboxylic acid ester bonds, while the viscosity of the polyester copolymer is not improved and the flame retardant effect is relatively low when copolymerized with other phosphorus compound monomers.

[0208] Table 3 shows that Examples 18-21 and Comparative Examples 5-6 illustrate that the thermoplastic polyester resin compositions prepared from polyester (A) and phosphorus-based flame retardant (B) simultaneously possess good flame retardancy and high molecular weight. Thermoplastic polyester resin compositions prepared by compounding nitrogen-based flame retardants or commonly used aluminum hydroxide flame retardants exhibit poor flame retardancy and are unlikely to produce a synergistic flame retardant effect.

[0209] Table 4 shows that Examples 22-27 and Comparative Examples 7-8 demonstrate that polyester resins prepared from diacids, aliphatic diols with 4-10 carbon atoms, and phosphorus compounds capable of forming carboxylic acid esters exhibit excellent flame retardancy while maintaining high molecular weight, high crystallization temperature, and high melting point, thus preserving excellent mechanical properties. When using aliphatic diols with 2 carbon atoms, excessively high processing temperatures lead to easy decomposition of the flame retardant, weakening its flame-retardant effect. Polyester resins obtained by introducing polyhydroxyl groups are amorphous, and their molecular weight cannot be increased.

Claims

1. A thermoplastic polyester resin composition comprising at least: a polyester (A) having a phosphorus-containing structure in repeating units and / or at the ends of the molecular chain, and a phosphorus-based flame retardant (B), characterized in that, The polyester (A) is composed of monomer units of dicarboxylic acids and / or derivatives thereof capable of forming esters, monomer units of diols with 4 to 10 carbon atoms, and monomer units of phosphorus-containing compounds capable of forming carboxylic acid ester groups.

2. The thermoplastic polyester resin composition according to claim 1, characterized in that, The content of monomer units from terephthalic acid and / or its ester-forming derivatives is 80-100 mol relative to the total amount of the dicarboxylic acid and / or its ester-forming derivative monomer units.

3. The thermoplastic polyester resin composition according to claim 1, characterized in that, The monomer units of the dicarboxylic acid and / or its ester-forming derivatives are composed of one or more elements selected from carbon, hydrogen, oxygen, and nitrogen.

4. The thermoplastic polyester resin composition according to claim 1, characterized in that, The content of monomer units from 1,4-butanediol is 90-100 mol relative to the total amount of the diol monomer units with 4 to 10 carbon atoms.

5. The thermoplastic polyester resin composition according to claim 1, characterized in that, The phosphorus-containing compound capable of forming a carboxylic acid ester group is selected from at least one of the following groups: [(6-oxo-6H-dibenzo[C,E][1,2]oxophosphazenehexane-6-yl)methyl]succinic acid, diethyl N,N-bis(2-hydroxyethyl)aminomethylenephosphonate and bis(4-carboxyphenyl)phenylphosphine oxide.

6. The thermoplastic polyester resin composition according to claim 1, characterized in that, The content of phosphorus-containing compound monomer units capable of forming carboxylic acid ester groups is less than 8 mol relative to the total amount of the dicarboxylic acid and / or its derivative monomer units capable of forming esters.

7. The thermoplastic polyester resin composition according to claim 1, characterized in that, The phosphorus-based flame retardant (B) is selected from at least one group consisting of phosphite compounds, phosphonate compounds, phosphate compounds, alkyl hypophosphite compounds, phosphate compounds, and phosphorazene compounds.

8. The thermoplastic polyester resin composition according to claim 7, characterized in that, The phosphorus-based flame retardant (B) includes at least an alkyl hypophosphite compound.

9. The thermoplastic polyester resin composition according to claim 1, characterized in that, The amount of phosphorus-based flame retardant (B) added is less than 8 wt% relative to the total mass of the thermoplastic polyester resin composition.

10. The thermoplastic polyester resin composition according to claim 1, characterized in that, The weight ratio of the phosphorus content (Pa) of polyester (A) to the phosphorus content (Pb) of phosphorus-based flame retardant (B), i.e., Pa / Pb, is 0.01 to 7.

00.

11. The thermoplastic polyester resin composition according to claim 1, characterized in that, The thermoplastic polyester resin composition was melted at a temperature 25°C higher than its melting point and then hot-pressed to obtain a 1.6 mm thick sample. When the sample was subjected to a vertical burning test, its flame retardant rating reached UL-94V-0.

12. A method for preparing the thermoplastic polyester resin composition according to any one of claims 1 to 11, characterized in that, The process includes the following steps: (1) esterification or transesterification of the diol monomer with 4 to 10 carbon atoms and the dicarboxylic acid and / or its derivative monomers that can form esters, at a temperature of 150-250°C under normal pressure and / or reduced pressure. After the esterification or transesterification is complete, the phosphorus-containing compound that can form carboxylic acid ester groups is added to the system, and then a condensation reaction is carried out at a temperature of 240-270°C and a pressure of less than 500 Pa to obtain a polyester (A) with a phosphorus-containing structure in the repeating unit and / or end of the molecular chain; (2) melt-blending the polyester (A) with a phosphorus-containing structure in the repeating unit and / or end of the molecular chain and the phosphorus-based flame retardant (B) to obtain a thermoplastic polyester resin composition.

13. A thermoplastic polyester composition material, characterized in that, The thermoplastic polyester composition material comprises the thermoplastic polyester resin composition according to any one of claims 1 to 11 and a filler (C), wherein the content of the filler (C) is 0.1 to 150 parts by weight relative to 100 parts by weight of the thermoplastic polyester resin composition according to any one of claims 1 to 11.

14. A molded article, characterized in that, It is made from the thermoplastic polyester resin composition according to any one of claims 1 to 11 or the thermoplastic polyester resin composition material according to claim 13.

15. An electronic and electrical insulation component, characterized in that, A polyester (A) containing repeating units in the molecular chain and / or having phosphorus-containing structures at the ends, wherein the polyester (A) is composed of dicarboxylic acid and / or its derivative monomer units that can form esters, diol monomer units having 4 to 10 carbon atoms, and phosphorus-containing compound monomer units that can form carboxylic acid ester groups.

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