Polyester composite material, preparation method therefor and use thereof

Abstract

The present application provides a polyester composite material, a preparation method therefor and a use thereof. In parts by weight, the polyester composite material comprises 20-50 parts of a polyester resin, 10-50 parts of a glass fiber, 10-20 parts of a first flame retardant, 0.5-3 parts of a second flame retardant, 2-15 parts of a third flame retardant, and 0.1-2 parts of a carbodiimide compound; the first flame retardant includes a phosphorus-based flame retardant; the second flame retardant includes a phosphorus-nitrogen-based flame retardant; and the third flame retardant includes a nitrogen-based flame retardant. In the present application, the polyester composite material not only has a high glow-wire ignition temperature, but also can maintain excellent mechanical properties in relatively harsh environments such as high temperature and high humidity, and has a long service life; moreover, the polyester composite material generates less mold deposit during processing, yields products having good surface quality, and meets the performance requirements for materials in fields such as electronic and electrical components.

Description

A polyester composite material, its preparation method and application Technical Field

[0001] This application belongs to the field of polymer materials technology, specifically relating to a polyester composite material, its preparation method, and its application. Background Technology

[0002] Polyesters are high molecular weight compounds formed by the condensation polymerization of diols, diacids, or polyols and polyacids. They possess excellent physicochemical properties and are widely used in packaging materials, building materials, and electronics. Among them, polybutylene terephthalate (PBT) is a milky white, semi-transparent to opaque, crystalline thermoplastic saturated polyester with excellent mechanical properties, electrical properties, heat resistance, and processing properties. It is particularly widely used in the fields of electronics, new energy vehicles, and communication equipment.

[0003] With the development of automation, intelligence, and integration in electronic and electrical components, higher requirements have been placed on the glow wire ignition temperature (GWIT) and relative tracking index (CTI) of PBT materials to prevent overheating and active ignition caused by poor contact, overload, short circuit, etc., during the use of PBT materials in electronic and electrical components. The International Electrotechnical Commission (IEC) of the European Union, in the IEC 60335 safety standard for household and similar appliances, stipulates that the flame retardant performance of plastic parts used in appliances that are left unattended for a long time must meet the UL 94 V0 rating and the material must not ignite within 30 seconds of glow wire contact at 750°C or the burning time must be less than 5 seconds, i.e., GWIT greater than 750°C.

[0004] Adding flame retardants can improve the flame retardant properties of materials and increase GWIT; however, on the one hand, the addition of flame retardants will affect the initial mechanical properties, resistance to damp heat aging, and processing properties of materials. Among these, the processing properties are manifested in the increased fouling during processing; on the other hand, the existing solutions have only a small improvement in GWIT and need to be further improved.

[0005] Therefore, developing a polyester composite material that combines high glow wire ignition temperature, excellent resistance to damp heat aging, minimal mold fouling during processing, good product appearance quality, and long service life is an urgent problem to be solved in this field. Summary of the Invention

[0006] This application provides a polyester composite material, its preparation method, and its application. The polyester composite material not only possesses a high glow wire ignition temperature, but also maintains good mechanical properties in harsh environments such as high temperature and high humidity, exhibiting a long service life. Furthermore, the polyester composite material generates less mold residue during processing, resulting in products with good surface quality, thus meeting the performance requirements of materials in fields such as electronic and electrical components.

[0007] In a first aspect, this application provides a polyester composite material, which, by weight, comprises 20-50 parts polyester resin, 10-50 parts glass fiber, 10-20 parts a first flame retardant, 0.5-3 parts a second flame retardant, 2-15 parts a third flame retardant, and 0.1-2 parts a carbodiimide compound; the first flame retardant comprises a phosphorus-based flame retardant; the second flame retardant comprises a phosphorus-nitrogen-based flame retardant; and the third flame retardant comprises a nitrogen-based flame retardant.

[0008] In this application, a specific composition of flame retardant is used, namely, a combination of a first flame retardant, a second flame retardant, and a third flame retardant of a specific type, which can effectively increase the glow wire ignition temperature of polyester material while ensuring low mold fouling. Furthermore, a specific content of carbodiimide compounds is used in combination with the flame retardant to achieve synergistic effects, ensuring a high glow wire ignition temperature while mitigating mold fouling problems in polyester material during processing, and also ensuring that the obtained product has little or no surface fiber floating, resulting in good appearance quality.

[0009] In this application, 20 to 50 parts of polyester resin can be, for example, 20 parts, 22 parts, 24 parts, 26 parts, 28 parts, 30 parts, 32 parts, 34 parts, 36 parts, 38 parts, 40 parts, 42 parts, 44 parts, 46 parts, 48 ​​parts, 50 parts or any range of the above values; preferably 27 to 43 parts.

[0010] In this application, 10 to 50 parts of glass fiber can be, for example, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50 parts or any of the above values; preferably 23 to 41 parts.

[0011] In this application, 10 to 20 parts of the first flame retardant can be, for example, 10 parts, 10.5 parts, 11 parts, 11.5 parts, 12 parts, 12.5 parts, 13 parts, 13.5 parts, 14 parts, 14.5 parts, 15 parts, 15.5 parts, 16 parts, 16.5 parts, 17 parts, 17.5 parts, 18 parts, 18.5 parts, 19 parts, 19.5 parts, 20 parts, or any of the above values; more preferably, 11.5 to 19.5 parts.

[0012] In this application, 0.5 to 3 parts of the second flame retardant can be, for example, 0.5 parts, 0.52 parts, 0.55 parts, 0.6 parts, 0.62 parts, 0.65 parts, 0.68 parts, 0.7 parts, 0.72 parts, 0.75 parts, 0.78 parts, 0.8 parts, 0.82 parts, 0.85 parts, 0.88 parts, 0.9 parts, 0.92 parts, 0.95 parts, 1 part, 1.02 parts, 1.04 parts, 1.06 parts, 1.08 parts, etc. The amounts are 1.1, 1.15, 1.2, 1.25, 1.3, 1.34, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2, 2.2, 2.4, 2.6, 2.8, 3, or any of the above values; more preferably 0.8 to 2 parts.

[0013] In this application, 2 to 15 parts of the third flame retardant can be, for example, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, 10 parts, 10.5 parts, 11 parts, 11.5 parts, 12 parts, 12.5 parts, 13 parts, 13.5 parts, 14 parts, 14.5 parts, 15 parts, or any of the above values; more preferably, 5.7 to 10.8 parts.

[0014] In this application, if the content of the third flame retardant is too high, it will lead to increased mold fouling during the injection molding process; if the content of the third flame retardant is too low, the ignition temperature of the glow wire will be low.

[0015] In this application, 0.1 to 2 parts of carbodiimide compound can be, for example, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, 2 parts, or any of the above values; more preferably, 0.7 to 1.5 parts.

[0016] In this application, too much carbodiamine compound leads to increased surface fiber floating and poor appearance quality of the product; too little carbodiamine compound leads to increased mold fouling during injection molding.

[0017] Preferably, the polyester resin comprises a polyester resin formed from a dicarboxylic acid and a diol.

[0018] In this application, the dicarboxylic acid includes aliphatic dicarboxylic acids and / or aromatic dicarboxylic acids, and the diol includes aliphatic diols.

[0019] Preferably, the aliphatic dicarboxylic acid includes C4-C20 aliphatic dicarboxylic acids, wherein the C4-C20 aliphatic dicarboxylic acid refers to an aliphatic dicarboxylic acid with 4 to 20 carbon atoms, for example, it can be 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or any range between the above values; for example, the C4-C20 aliphatic dicarboxylic acid includes succinic acid, glutaric acid, adipic acid, azelaic acid or sebacic acid, etc.

[0020] Preferably, the aromatic dicarboxylic acid includes at least one of terephthalic acid, phthalic acid, isophthalic acid, or furanyl dicarboxylic acid.

[0021] Preferably, the aliphatic diol includes C2-C20 aliphatic diols, wherein the C2-C20 aliphatic diols refer to aliphatic diols with 2 to 20 carbon atoms, for example, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or any range of the above values; for example, the C2-C20 aliphatic diols include butanediol, pentanediol, hexanediol, nonanediol or decanediol, etc.

[0022] In this application, the polyester resin includes polybutylene terephthalate (PBT) and / or polyethylene terephthalate (PET).

[0023] Preferably, at 23°C, the intrinsic viscosity of the polyester resin is <1.4 dl / g.

[0024] In this application, the intrinsic viscosity of the polyester resin is tested in accordance with GB / T 1632-1993 Determination of viscosity number and intrinsic viscosity of polymer dilute solutions.

[0025] Preferably, the mass ratio of the first flame retardant, the second flame retardant, and the third flame retardant is (10~18):1:(1~10), wherein the specific values ​​of (10~18) can be, for example, 10, 10.2, 10.4, 10.6, 10.8, 11, 11.2, 11.4, 11.6, 11.8, 12, 12.2, 12.4, 12.6, 12.8, 13, 13.2, 13.4, 13.6, 13.8, 14, 14.2, 14.4, 14.6, 14.8, 15, 15.2, 15.4, 15.6, 15.8, 16, 16.2, 16.4, 16.6, 16.8, 17, 17.2, 17.4, 1 The range of 7.6, 17.8, 18 or any of the above values; the specific values ​​in (1~10) can be, for example, 1, 1.2, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, 2.8, 3, 3.2, 3.4, 3.6, 3.8, 4, 4.2, 4.4, 4.6, 4.8, 5, 5.2, 5.4, 5.6, 5.8, 6, 6.2, 6.4, 6.6, 6.8, 7, 7.2, 7.4, 7.6, 7.8, 8, 8.2, 8.4, 8.6, 8.8, 9, 9.2, 9.4, 9.6, 9.8, 10 or any of the above values; preferably (12~15):1:(5.8~7.8).

[0026] Preferably, the phosphorus-based flame retardant includes at least one of hypophosphite or phosphate ester compounds.

[0027] Preferably, the hypophosphite includes at least one of diethylaluminum hypophosphite, phenylaluminum hypophosphite, methylaluminum hypophosphite, diisobutylaluminum hypophosphite, methylethylaluminum hypophosphite, di-tert-butylaluminum hypophosphite, or aluminum hypophosphite.

[0028] Preferably, the phosphate ester compound includes at least one of tributyl phosphate, trioctyl phosphate, triphenyl phosphate, resorcinol bis(diphenyl phosphate) or toluene diphenyl phosphate.

[0029] Preferably, the phosphorus-nitrogen flame retardant includes melamine polyphosphate and / or melamine phosphate.

[0030] Preferably, the nitrogen-based flame retardant includes at least one of melamine cyanurate, melamine borate, or melamine; more preferably, melamine cyanurate and / or melamine borate.

[0031] Preferably, the carbodiimide compounds include monomeric carbodiimides and / or polymeric carbodiimides.

[0032] Preferably, the monomeric carbodiimide includes at least one of dicyclohexylcarbodiimide, N,N'-diisopropylcarbodiimide, N,N'-di(2,6-diisopropylphenyl)carbodiimide, or 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride.

[0033] Preferably, the polymeric carbodiimide includes aliphatic polymeric carbodiimide and / or aromatic polymeric carbodiimide; the number average molecular weight of the polymeric carbodiimide is 500 to 30,000.

[0034] In this application, the carbodiimide compounds include monomeric carbodiimides and polymeric carbodiimides, wherein the mass ratio of the monomeric carbodiimides to the polymeric carbodiimides is 1:(0.5~2); wherein, the specific value of (0.5~2) can be, for example, 0.5, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, 2 or any range between the above values; more preferably, it is 1:(1.2~1.8).

[0035] Preferably, the polyester composite material further includes 0.5 to 4 parts by weight of toughening agent, for example, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts or any range of the above values.

[0036] Preferably, the toughening agent includes at least one of nitrile rubber, polybutadiene rubber, ethylene-methyl acrylate-glycidyl methacrylate copolymer, or methyl methacrylate-butadiene-styrene copolymer.

[0037] In this application, the polyester composite material may also contain 0.5 to 10 parts of other additives as needed; the other additives include, but are not limited to, compatibilizers, antioxidants, lubricants, antistatic agents or colorants.

[0038] In this application, the amount of compatibilizer, antioxidant, lubricant, antistatic agent and colorant in the polyester composite material is 0.1 to 3 parts by weight.

[0039] In this application, the compatibilizer includes, but is not limited to, maleic anhydride-grafted polyethylene, maleic anhydride-grafted polypropylene, maleic anhydride-grafted polyolefin elastomer, or glycidyl methacrylate-grafted polyolefin elastomer; the antioxidant includes, but is not limited to, hindered phenolic antioxidants (such as antioxidant 1010, antioxidant 1076, etc.) or phosphite antioxidants (such as antioxidant 168); the lubricant includes, but is not limited to, silicone powder, N,N′-ethylene bis-stearamide, or pentaerythritol stearate; and the antistatic agent includes, but is not limited to, quaternary ammonium salt compounds.

[0040] In this application, the polyester resin content in the polyester composite material is ≥20% by mass, preferably ≥30%.

[0041] Secondly, this application provides a method for preparing the polyester composite material according to the first aspect, the method comprising:

[0042] Polyester resin, glass fiber, a first flame retardant, a second flame retardant, a third flame retardant, a carbodiimide compound, and optionally a toughening agent are mixed and extruded to obtain the polyester composite material.

[0043] Preferably, the extrusion temperature is 200~320℃, for example, it can be 200℃, 220℃, 240℃, 260℃, 280℃, 300℃, 320℃ or any range between the above values.

[0044] Thirdly, this application provides an electronic and electrical component, which includes the polyester composite material described in the first aspect.

[0045] The numerical range described in this application includes not only the point values ​​listed above, but also any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of brevity, this application will not exhaustively list the specific point values ​​included in the range.

[0046] Compared with the prior art, the beneficial effects of this application are as follows:

[0047] In this application, the polyester composite material uses a specific composition of flame retardants, namely, a combination of a specific type of first flame retardant, a second flame retardant, and a third flame retardant, and the addition of a specific amount of carbodiimide compounds to the flame retardants. This allows the polyester composite material to have both a high glow wire ignition temperature and excellent resistance to damp heat aging. Furthermore, the problem of mold fouling during the processing of the polyester material can be effectively alleviated, and the resulting product has less surface fiber and a good appearance quality. Detailed Implementation

[0048] The technical solution of this application will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of this application and should not be construed as specific limitations thereof.

[0049] All materials used in this application are commercially available. Unless otherwise specified, the materials used in this application are as follows:

[0050] PBT; purchased from Sinopec Yizheng Chemical Fiber Co., Ltd., grade GX112, intrinsic viscosity 0.82 dl / g.

[0051] Glass fiber: purchased from Jushi Co., Ltd., grade ECS13-03-834A, diameter 13μm.

[0052] Diethylaluminum hypophosphite: purchased from Liaoning Kingfa Biomaterials Co., Ltd., grade BEP-820H.

[0053] Aluminum phenylphosphite: purchased from Henan Weitixi Chemical Technology Co., Ltd., brand name PADP.

[0054] Aluminum hypophosphite: purchased from Wuhan Hanye Wuzhou Chemical New Materials Co., Ltd.

[0055] Melamine polyphosphate (MPP): purchased from Budenheim Ibérica SLU, brand name BUDIT 3141.

[0056] Melamine cyanurate (MCA): Purchased from Sichuan Fine Chemical Research and Design Institute.

[0057] Monomeric carbodiimide: N,N'-bis(2,6-diisopropylphenyl)carbodiimide, purchased from RASCHIG GmbH, brand name Stabilizer7000.

[0058] Polymeric carbodiimide: purchased from Shanghai Langyi Functional Materials Co., Ltd., brand name HYMAX 213.

[0059] Epoxy resin: Bisphenol A diglycidyl ether, YD-019, Guodu Chemical Co., Ltd.

[0060] Toughening agent: methyl methacrylate-butadiene-styrene terpolymer, purchased from Kaneka, Japan, brand name B564;

[0061] Melamine and triphenyl phosphate are sourced from commercially available products.

[0062] Examples 1-17, Comparative Examples 1-7

[0063] Examples 1-17 and Comparative Examples 1-7 each provide a polyester composite material. The formulations of the polyester composite materials are shown in Tables 1-5 by weight. " / " indicates that the component is not in the formulation; M1 represents the mass ratio of the first flame retardant, the second flame retardant, and the third flame retardant. The preparation method of the polyester composite material includes: mixing each component in a mixer according to the proportions in the table until homogeneous to obtain a premix; then melting and mixing the obtained premix in a first-section twin-screw extruder, and extruding and granulating to obtain the polyester composite material. The extrusion temperature from zone one to the die head is 160℃-260℃-260℃-240℃-220℃-220℃-220℃-240℃-260℃, the main extruder speed is 400 rpm, and the feeding speed is 220 kg / h.

[0064]

[0065]

[0066]

[0067]

[0068]

[0069] Performance testing

[0070] Polyester composite materials are injection molded at temperatures of 230-290℃, and the resulting products are subjected to the following performance tests.

[0071] (1) GWIT: According to IEC 60695-2-13 standard, the sample thickness is 3mm;

[0072] (2) Resistance to damp heat aging: The initial tensile strength of the product was tested and recorded as L1; then the product was aged at 85℃ and 85% humidity for 1008h, and the tensile strength after aging was tested and recorded as L2; ​​and the tensile strength retention rate was calculated and recorded as L; L=L2 / L1×100%;

[0073] The tensile strength was tested according to the method specified in GB / T 1040.2-2022 "Determination of tensile properties of plastics - Part 2: Test conditions for molded and extruded plastics", with a test speed of 10 mm / min.

[0074] (3) Mold fouling: The obtained product is placed at a constant temperature of 120°C for 5 hours, and the TVOC (total volatile organic compounds) content is tested according to VDA 277 standard; the lower the TVOC content, the fewer small molecules in the material, and the less mold fouling is generated during injection molding.

[0075] (4) Appearance: Observe whether there are floating fibers on the surface of the product; and divide them into three grades according to the percentage of floating fibers in the product area; where 0 indicates that the percentage of floating fibers in the product area is <0.5%; 1 indicates that the percentage of floating fibers in the product area is 0.5~2%; and 3 indicates that the percentage of floating fibers in the product area is ≥2%.

[0076] The specific test results are shown in Table 6.

[0077]

[0078] As shown in Table 6, the polyester composite material provided in this application uses a specific composition of flame retardants, namely, a specific type of first flame retardant, second flame retardant, and third flame retardant compounded together, and a specific amount of carbodiimide compound compounded with the flame retardants. This allows the polyester composite material to have both a high glow wire ignition temperature and excellent resistance to damp heat aging. The problem of mold fouling during the processing of the polyester material can be effectively alleviated, and the resulting product has less surface fiber and good appearance quality. The polyester composite material has a GWIT ≥ 750℃, an initial tensile strength ≥ 80MPa, and after aging for 1008 hours at a temperature of 85℃ and a humidity of 85%, the tensile strength retention rate is ≥ 78%, the TVOC content is ≤ 200μgC / g, and there is little mold fouling and good appearance quality.

[0079] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above descriptions are merely specific embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A polyester composite material comprising, in parts by weight, 20 to 50 parts of a polyester resin, 10 to 50 parts of glass fibers, 10 to 20 parts of a first flame retardant, 0.5 to 3 parts of a second flame retardant, 2 to 15 parts of a third flame retardant, and 0.1 to 2 parts of a carbodiimide compound. The first flame retardant comprises a phosphorus-based flame retardant. The second flame retardant comprises a phosphorus-nitrogen-based flame retardant. The third flame retardant comprises a nitrogen-based flame retardant.

2. The polyester composite of claim 1, wherein, The polyester resin comprises a polyester resin formed from a diacid and a diol. 3.The polyester composite material according to claim 1 or 2, wherein the polyester resin comprises polybutylene terephthalate and / or polyethylene terephthalate.

4. The polyester composite material according to any one of claims 1 to 3, wherein, The mass ratio of the first flame retardant, the second flame retardant, and the third flame retardant is (8 to 18) : 1 : (1 to 10), preferably (12 to 15) : 1 : (5.8 to 7.8).

5. The polyester composite material according to any one of claims 1 to 4, wherein, The phosphorus-based flame retardant comprises at least one of a hypophosphite or a phosphate compound. Preferably, the hypophosphite comprises at least one of aluminum diethylphosphinate, aluminum phenylphosphinate, aluminum methylphosphinate, aluminum diisobutylphosphinate, aluminum methylethylphosphinate, aluminum di-t-butylphosphinate, or aluminum hypophosphite. Preferably, the phosphate compound comprises at least one of tributyl phosphate, trioctyl phosphate, triphenyl phosphate, resorcinol bis(diphenyl phosphate), or cresyl diphenyl phosphate.

6. The polyester composite material according to any one of claims 1 to 5, wherein, The phosphorus-nitrogen-based flame retardant comprises melamine polyphosphate and / or melamine phosphate. Preferably, the nitrogen-based flame retardant comprises at least one of melamine cyanurate, melamine borate, or melamine; more preferably melamine cyanurate and / or melamine borate.

7. The polyester composite of any one of claims 1-6, wherein, The content of the carbodiimide compound in the polyester composite material is 0.7 to 1.5 parts by weight. Preferably, the carbodiimide compound comprises a monomeric carbodiimide and / or a polymeric carbodiimide. Preferably, the carbodiimide compound comprises a monomeric carbodiimine and a polymeric carbodiimine, and the mass ratio of the monomeric carbodiimine to the polymeric carbodiimine is 1 : (0.5 to 2). Preferably, the monomeric carbodiimide comprises at least one of dicyclohexylcarbodiimide, N, N'-diisopropylcarbodiimide, N, N'-di(2,6-diisopropylphenyl)carbodiimide, or 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride.

8. The polyester composite material according to any one of claims 1 to 7, wherein, The polyester composite material further comprises 0.5 to 4 parts of a toughening agent by weight. Preferably, the toughening agent comprises at least one of nitrile rubber, polybutadiene rubber, ethylene-methyl acrylate-glycidyl methacrylate copolymer, or methyl methacrylate-butadiene-styrene copolymer. 9.A method for preparing the polyester composite material according to any one of claims 1 to 8, comprising: mixing the polyester resin, the glass fibers, the first flame retardant, the second flame retardant, the third flame retardant, and the carbodiimide compound, and optionally the toughening agent, and extruding to obtain the polyester composite material.

10. The production method according to claim 9, wherein The temperature for the extrusion is 200 to 320℃.

11. An electronic or electric component comprising the polyester composite material according to any one of claims 1 to 8.

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