A pbt modified material, its preparation method and application

Abstract

The application discloses a PBT modified material and a preparation method and application thereof, and belongs to the technical field of high polymer engineering plastics. The PBT modified material provided by the application comprises the following components in parts by mass: PBT resin 33-68 parts, glass fiber 18-40 parts, flame retardant 10-22 parts, hydrotalcite and / or zinc oxide 0.08-0.49 parts. The flame retardant is a coated flame retardant with a core-shell structure, the core layer is melamine polyphosphate, and the shell layer is aluminum diethyl phosphite. The mass ratio of the shell layer to the core layer is greater than or equal to 1. The TVOC of the flame retardant under the condition of 180 DEG C and 60 min is less than or equal to 300 mu g C / g. The PBT modified material provided by the application has low odor and low metal corrosion, and also has good mechanical properties and flame retardance. Meanwhile, the preparation method of the PBT modified material is simple, and is beneficial to practical application.

Description

Technical Field

[0001] This invention belongs to the field of polymer engineering plastics technology, and particularly relates to a PBT modified material, its preparation method and application. Background Technology

[0002] With EU restrictions on halogens in certain products, halogen-free flame retardant materials are increasingly being promoted and applied. Alkyl phosphinate flame retardants are among the most widely used halogen-free flame retardants. In PBT modification, the most mature material is the aluminum diethyl phosphinate flame retardant system. The flame retardant system composed of aluminum diethyl phosphinate and melamine polyphosphate can achieve good flame retardant performance with a relatively low amount of flame retardant added, while also obtaining relatively good mechanical properties among halogen-free flame retardant systems.

[0003] However, there are two problems. First, alkyl phosphinate flame retardant systems are highly corrosive to metals, causing significant corrosion to extruders, injection molding machines, and equipment in the production chain. Second, with the rise and development of new energy vehicles, the application of halogen-free flame retardant reinforced PBT materials is becoming increasingly widespread, but the odor of halogen-free PBT materials used in automotive interiors is difficult to meet application requirements.

[0004] Existing technologies have proposed solutions to the first problem, such as CN114605789A, which proposes improving the corrosion resistance of halogen-free flame-retardant reinforced PBT to metals by adding basic magnesium sulfate whiskers. However, the mechanical properties of the product obtained by this solution are significantly reduced, making it difficult to meet the material's mechanical performance requirements. As for the second problem, existing technologies have not proposed effective solutions. Therefore, developing a halogen-free flame-retardant reinforced PBT modified material with low odor, low metal corrosion, and excellent mechanical properties has become a research hotspot. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a PBT modified material with low odor, low metal corrosion and excellent mechanical and flame retardant properties, as well as its preparation method and application.

[0006] To achieve the above objectives, in a first aspect of the present invention, the present invention provides a PBT modified material comprising the following components in parts by weight: 33-68 parts of PBT resin, 18-40 parts of glass fiber, 10-22 parts of flame retardant, and 0.08-0.49 parts of hydrotalcite and / or zinc oxide.

[0007] The flame retardant is a core-shell structured coated flame retardant, with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite; the mass ratio of the shell layer to the core layer is ≥1.

[0008] The flame retardant has a TVOC of ≤300 μgC / g at 180℃ for 60 min.

[0009] The present invention provides a PBT modified material by introducing a core-shell structured coated flame retardant with a specific TVOC (total volatile organic compounds) content, and by selecting hydrotalcite and / or zinc oxide for compounding. The resulting PBT modified material not only meets the requirements of halogen-free flame retardancy, but also has low odor, low metal corrosion characteristics, and good mechanical properties.

[0010] Specifically, on the one hand, this invention introduces a core-shell structured coated flame retardant, wherein the core layer is melamine polyphosphate and the shell layer is diethylaluminum hypophosphite. This core-shell structure significantly reduces the precipitation characteristics of melamine polyphosphate, thereby reducing its corrosiveness to metals. Simultaneously, this invention further limits the TVOC content range of the coated flame retardant at 180°C for 60 minutes, achieving low corrosiveness to metals while also improving the product's odor level, resulting in a low-odor product. Furthermore, this invention limits the mass ratio of the shell layer to the core layer to be ≥1, ensuring that the product meets the requirements for halogen-free flame retardancy when added as a flame retardant. On the other hand, this invention selects at least one of hydrotalcite and zinc oxide. These two substances synergistically enhance the product's odor level, reduce metal corrosion, and maintain the product's flame retardant rating, while also preventing degradation of PBT resin, thereby reducing the loss of mechanical properties and obtaining a product with excellent mechanical properties.

[0011] The test method for the TVOC content of the flame retardant at 180°C for 60 minutes was obtained by referring to VDA277-1995.

[0012] For example, in the PBT modified material, the PBT resin can be any point value or any two-point range between 33 and 68 parts, such as 35-65 parts, or 33, 35, 38, 40, 42, 45, 48, 50, 52, 55, 58, 60, 62, 65, 68, etc.; the glass fiber can be any point value or any two-point range between 18 and 40 parts, such as 20-38 parts, or 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, etc.; the flame retardant can be any point value or any two-point range between 10 and 22 parts. The point range value can be, for example, 12-20 parts, or 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 parts, etc.; the hydrotalcite and / or zinc oxide can be any point value or any two-point range value between 0.08-0.49 parts, for example, 0.1-0.4 parts, or 0.08, 0.1, 0.12, 0.15, 0.18, 0.2, 0.22, 0.25, 0.28, 0.3, 0.32, 0.35, 0.38, 0.4, 0.42, 0.44, 0.46, 0.48, 0.49 parts, etc.

[0013] Preferably, in the PBT modified material, the mass percentage of PBT resin is ≥33%.

[0014] More preferably, the mass percentage of PBT resin in the PBT modified material is between 48% and 55%.

[0015] Preferably, the intrinsic viscosity of the PBT resin is 0.66-1.30 dl / g. The intrinsic viscosity of the PBT resin is obtained by testing with reference to GB / T 14190-2017.

[0016] This invention does not impose specific requirements on the intrinsic viscosity of the PBT resin; optimal results can be achieved within the intrinsic viscosity range of 0.66-1.30 dl / g provided by this invention. Exemplarily, the intrinsic viscosity of the PBT resin can be any point value or any two points within the range of 0.66-1.30 dl / g, such as 0.66 dl / g, 0.70 dl / g, 0.75 dl / g, 0.80 dl / g, 0.85 dl / g, 0.90 dl / g, 1.00 dl / g, 1.05 dl / g, 1.10 dl / g, 1.15 dl / g, 1.20 dl / g, 1.25 dl / g, 1.30 dl / g, etc.

[0017] Preferably, the glass fiber is alkali-free glass fiber. This invention does not impose specific requirements on the fiber diameter, cross-sectional shape (e.g., circular, flat, irregular shape), or fiber morphology (e.g., raw filament, coarse sand, ground, etc.) of the glass fiber.

[0018] For example, the mass ratio of the shell to the core can be any point value or any two points between ≥1, such as 1-2, 1-3, 1-5, 1-7, or 1, 2, 3, 4, 5, 6, 7, etc.

[0019] As a preferred embodiment of the PBT modified material of the present invention, the mass percentage of hydrotalcite and / or zinc oxide is ≤0.9% based on the mass of PBT resin.

[0020] For example, the mass percentage of hydrotalcite and / or zinc oxide, based on the mass of PBT resin, can be any point value or any two points within a range of ≤0.9%, such as 0.1-0.9%, 0.3-0.9%, 0.5-0.9%, 0.3-0.9%, 0.7-0.9%, etc., or 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, etc.

[0021] Preferably, the mass percentage of hydrotalcite and / or zinc oxide is ≤0.7% based on the mass of PBT resin.

[0022] This invention has found that the mass percentage of hydrotalcite and / or zinc oxide in PBT resin affects the overall performance of the product. When the mass percentage of hydrotalcite and / or zinc oxide in PBT resin is too high, it will lead to the degradation of PBT resin, thereby reducing the mechanical properties of the product. Therefore, when the mass percentage of hydrotalcite and / or zinc oxide is limited to ≤0.9% based on the mass of PBT resin, especially ≤0.7%, the overall performance of the obtained product is better.

[0023] As a preferred embodiment of the PBT modified material of the present invention, the mass percentage of hydrotalcite and / or zinc oxide is ≥0.9% based on the mass of the flame retardant.

[0024] For example, the mass percentage of hydrotalcite and / or zinc oxide, based on the mass of the flame retardant, can be any point value or any two points within a range of ≥0.9%, such as 0.9-4.2%, 0.9-2.4%, 0.9-1.5%, 0.9-1.0%, etc., or 0.9%, 1%, 1.2%, 1.5%, 1.8%, 2.0%, 2.2%, 2.5%, 2.8%, 3.0%, 3.2%, 3.5%, 3.8%, 4.0%, 4.2%, etc.

[0025] Preferably, the mass percentage of hydrotalcite and / or zinc oxide is ≥1.0% based on the mass of the flame retardant.

[0026] This invention has found that the mass percentage of hydrotalcite and / or zinc oxide in flame retardants affects the odor level and metal corrosivity of the product. When the amount of acid absorbent added is too small, it cannot effectively synergize with the flame retardant, thus increasing the odor level of the product and showing an increasing trend in metal corrosion. When the mass percentage of hydrotalcite and / or zinc oxide is ≥0.9% based on the mass of the flame retardant, especially when the mass percentage of hydrotalcite and / or zinc oxide is ≥1.0%, the overall performance of the obtained product is better.

[0027] In a preferred embodiment of the PBT modified material of the present invention, the mass ratio of the core layer to the shell layer is 1.8-5.2.

[0028] It should be noted that the mass ratio of the core and shell layers of the flame retardant can be determined by measuring the aluminum content in aluminum diethylphosphite, deriving the shell layer mass, and subtracting the shell layer weight from the total weight to obtain the core layer mass, thus yielding the mass ratio of the core and shell layers. The aluminum content was determined using ICP (inductively coupled plasma mass spectrometry), and the aluminum percentage in aluminum diethylphosphite was 6.92%.

[0029] For example, in the flame retardant, the mass ratio of the shell layer to the core layer can be any point value or any two points between 1.8 and 5.2, such as 2-5, or 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.2, 4.4, 4.6, 4.8, 5.0, 5.2, etc.

[0030] This invention has found that the mass ratio of the shell to the core layer in a flame retardant affects the odor level and corrosivity to metals of the product. When the mass ratio of the shell to the core layer in the flame retardant is further selected to be 1.8-5.2, the overall performance of the resulting product is even better.

[0031] Preferably, the flame retardant can be prepared using any method known in the art for preparing a core-shell structure, such as solution method, gas phase method, template method, etc. This invention does not limit the preparation method of the flame retardant; any coated flame retardant capable of forming a core-shell structure can achieve the effects of this invention.

[0032] For example, the preparation method of the coated flame retardant may be as follows:

[0033] (1) Disperse melamine polyphosphate in water to obtain a melamine polyphosphate suspension;

[0034] (2) Add diethyl hypophosphite aqueous solution to melamine polyphosphate suspension, then add aluminum-containing compound aqueous solution, and then carry out coating reaction;

[0035] (3) Filter the system after the coating reaction, collect the filter residue and wash and dry it to obtain the coated flame retardant.

[0036] Preferably, in the melamine polyphosphate suspension, the mass-to-volume ratio of melamine polyphosphate to water is 1 g:(1-100) mL.

[0037] Preferably, the mass percentage of diethyl hypophosphite in the diethyl phosphite aqueous solution is 20-50%.

[0038] Preferably, the aluminum-containing compound aqueous solution contains 30-60% by mass of the aluminum-containing compound.

[0039] Preferably, in step (2), the coating reaction temperature is 30-90℃.

[0040] For example, the diethyl hypophosphite includes sodium diethyl hypophosphite; the aluminum-containing compound includes aluminum sulfate.

[0041] Furthermore, the present invention removes volatile organic compounds from the prepared coated flame retardant until its TVOC is ≤300μgC / g when tested at 180℃ for 60min; wherein the removal method is to volatilize under vacuum of ≤100Pa and temperature of 160-220℃ for 2-4h until the TVOC value obtained when tested at 180℃ for 60min reaches a specific value.

[0042] As a preferred embodiment of the PBT modified material of the present invention, the flame retardant has a TVOC ≤ 280 μgC / g under the conditions of 180°C and 60 min.

[0043] For example, the TVOC of the flame retardant at 180°C for 60 minutes can be any point value or any two points within a range of ≤280 μgC / g, such as 170 μgC / g, 178 μgC / g, 190 μgC / g, 200 μgC / g, 215 μgC / g, 220 μgC / g, 225 μgC / g, 230 μgC / g, 235 μgC / g, 240 μgC / g, 245 μgC / g, 250 μgC / g, 255 μgC / g, 260 μgC / g, 265 μgC / g, 270 μgC / g, 275 μgC / g, 277 μgC / g, etc.

[0044] This invention has found that the TVOC of flame retardants at 180°C and 60 min not only affects the odor level of the product, but also its corrosivity to metals. When the TVOC of the flame retardant at 180°C and 60 min is further selected to be ≤280 μgC / g, the resulting product has a better odor level and lower corrosivity to metals.

[0045] In a preferred embodiment of the PBT modified material of the present invention, the mass ratio of hydrotalcite to zinc oxide is (1.5-6):1.

[0046] For example, in the acid absorbent, the mass ratio of hydrotalcite to zinc oxide can be any point value or any two points between (1.5-6):1, such as (2-6):1, or 1.5:1, 2:1, 3:1, 4:1, 5:1, 6:1, etc.

[0047] The present invention has found that when the mass ratio of hydrotalcite to zinc oxide is further selected to be (1.5-6):1, the overall performance of the obtained product is better.

[0048] As a preferred embodiment of the PBT modified material of the present invention, the PBT modified material further includes 0.1-5 parts of processing aids.

[0049] As a preferred embodiment of the PBT modified material of the present invention, the processing aid includes at least one of antioxidants, lubricants, nucleating agents, laser aids, and weathering agents.

[0050] Exemplarily, the antioxidant comprises at least one of pentaerythritol tetrakis[β(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], pentaerythritol tetrakis(3-lauryl thiopropionate), and octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; the lubricant comprises at least one of pentaerythritol fatty acid ester, oxidized polyethylene wax, and silicone; and the nucleating agent comprises Klein's Na + The laser aid comprises at least one of the following: LICOMONT NAV101 PWD salt, Honeywell zinc ionomer 295A, and talc powder of 3000-5000 mesh; the laser aid comprises at least one of the following: basic copper phosphonate, a polymer of antimony trioxide coated with metal oxide and polyamide, a mixture of titanium dioxide and pigment; the weathering agent comprises at least one of the following: 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2-(2-hydroxy-3,5-bis(a,a-dimethylbenzyl)phenyl)benzotriazole, and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate.

[0051] In a second aspect, the present invention provides a method for preparing the PBT modified material, the method comprising the following steps:

[0052] After drying, the raw materials are weighed and mixed, then fed into a twin-screw extruder. After extrusion, stranding, cooling, pelletizing, and drying, PBT modified material is obtained.

[0053] In a preferred embodiment of the preparation method described in this invention, the feed rate of the twin-screw extruder is 350-550 kg / h; the screw temperatures of each section of the twin-screw extruder from the feed port to the die head are 160-180℃, 230-260℃, 230-260℃, 230-260℃, 210-250℃, 210-250℃, 200-240℃, 200-240℃, 200-240℃, 200-240℃, and the screw speed is 350-600 rpm.

[0054] In a third aspect, the present invention provides the application of the PBT modified material in the preparation of materials for the electronic, electrical, and automotive fields.

[0055] For example, the PBT modified material is used in the preparation of materials such as relays and cooling fans in the field of electronics and electrical engineering, and in the preparation of materials such as air conditioning controllers for new energy vehicles in the automotive field.

[0056] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0057] This invention provides a PBT modified material in which a core-shell structured, coated flame retardant with a specific TVOC content is introduced. Hydrotalcite and / or zinc oxide are selected, and their synergistic effect results in a PBT modified material that exhibits low odor, low metal corrosion, and excellent mechanical properties and flame retardancy. Furthermore, the preparation method of the PBT modified material provided by this invention is simple and beneficial for practical applications. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of the metal corrosion testing process;

[0059] Figure 2 This is a schematic diagram of the results of Level I corrosion in a metal corrosion test;

[0060] Figure 3 This is a schematic diagram of the results of Level II corrosion in a metal corrosion test;

[0061] Figure 4 This is a schematic diagram of the results of Level III corrosion in a metal corrosion test;

[0062] Figure 5 This is a schematic diagram of the Class IV corrosion results in a metal corrosion test. Detailed Implementation

[0063] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0064] Unless otherwise specified, the reagents, methods and equipment used in this invention are all conventional reagents, methods and equipment in the field.

[0065] PBT-1: PBT GX121, intrinsic viscosity is 1.00 dl / g, Yizheng Branch of China Petrochemical Corporation Asset Management Co., Ltd.

[0066] PBT-2: PBT GL236, intrinsic viscosity is 1.28 dl / g, Sinopec Yizheng Chemical Fiber;

[0067] Fiberglass: ECS11-4.5-534A, Jushi Group;

[0068] Flame retardant 1: A coated flame retardant with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite, the mass ratio of the shell layer to the core layer being 2:1; the TVOC at 180℃ for 60 min is 215 μgC / g; self-made.

[0069] Flame retardant 2: Coated flame retardant, with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite, the mass ratio of the shell layer to the core layer is 3:1; the TVOC at 180℃ for 60 min is 277 μgC / g; self-made;

[0070] Flame retardant 3: A coated flame retardant with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite, the mass ratio of the shell layer to the core layer being 1:1; the TVOC at 180℃ for 60 min is 211 μgC / g; self-made.

[0071] Flame retardant 4: Coated flame retardant, with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite, the mass ratio of the shell layer to the core layer is 5:1; the TVOC at 180℃ for 60 min is 217 μgC / g; self-made;

[0072] Flame retardant 5: A coated flame retardant with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite, with a mass ratio of shell to core of 2:1; TVOC at 180℃ for 60 min is 298 μgC / g; self-made.

[0073] Flame retardant 6: A coated flame retardant with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite, with a mass ratio of shell to core of 2:1; TVOC at 180℃ for 60 min is 178 μgC / g; self-made.

[0074] Flame retardant 7: A coated flame retardant with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite, the mass ratio of the shell layer to the core layer being 2:1; the TVOC at 180℃ for 60 min is 342 μgC / g; self-made.

[0075] Flame retardant 8: A coated flame retardant with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite, the mass ratio of the shell layer to the core layer being 0.5:1; the TVOC at 180℃ for 60 min is 219 μgC / g; self-made;

[0076] Flame retardant 9: A coated flame retardant with a core layer of melamine cyanurate and a shell layer of aluminum diethylphosphite, the mass ratio of the shell layer to the core layer being 2:1; the TVOC at 180℃ for 60 min is 213 μgC / g; self-made.

[0077] Flame retardant 10: aluminum diethylphosphite, commercially available; TVOC at 180℃ for 60 min is 210 μgC / g;

[0078] Flame retardant 11: Melamine polyphosphate, commercially available; TVOC at 180℃ for 60 min is 216 μgC / g;

[0079] Hydrotalcite: DHT-4A-2, Kyowa Chemical Industry Co., Ltd.;

[0080] Zinc oxide: Commercially available;

[0081] Magnesium oxide: Commercially available;

[0082] Lubricant: Pentaerythritol fatty acid ester, commercially available;

[0083] Antioxidant, pentaerythritol tetrakis[β(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], commercially available;

[0084] The antioxidants and lubricants used in the parallel experiments of the examples and comparative examples were consistent;

[0085] Flame retardants 1-8 used were prepared in-house, and the preparation method is as follows:

[0086] (1) Disperse melamine polyphosphate in water (the mass-volume ratio of melamine polyphosphate to water is 1g:4mL) to obtain a melamine polyphosphate suspension;

[0087] (2) Add an aqueous solution of sodium diethyl phosphite (the mass percentage of sodium diethyl phosphite in the aqueous solution of sodium diethyl phosphite is 30%) to the melamine polyphosphate suspension, and then add an aqueous solution of aluminum sulfate (the mass percentage of aluminum sulfate in the aqueous solution of aluminum sulfate is 50%), and carry out the coating reaction at 70°C.

[0088] (3) Filter the system after the coating reaction, collect the filter residue and wash and dry it. Then place the dried product under a vacuum of 100 Pa and a temperature of 200 °C for 2-4 hours to devolve. Then take it out and test its TVOC content at 180 °C for 60 min to obtain the corresponding flame retardant.

[0089] The difference in the mass ratio of the core and shell layers in the flame retardant is achieved by controlling the amount of melamine polyphosphate and sodium diethylphosphite added during the preparation process; the difference in the TVOC content in the flame retardant is achieved by controlling the devolatilization time.

[0090] The preparation method of flame retardant 9 is the same as that of flame retardant 1, except that melamine polyphosphate is replaced with melamine cyanurate.

[0091] Flame retardant 10-11: The commercially available product is placed under a vacuum of 100 Pa and a temperature of 200 °C for 2-4 hours to devolve, and then taken out and tested for its TVOC content at 180 °C for 60 minutes to obtain the corresponding flame retardant.

[0092] Examples 1-14 and Comparative Examples 1-7

[0093] The present invention provides a PBT modified material in the embodiments and comparative examples. The components (parts by mass) of the PBT modified material are shown in Tables 1-3; wherein V1 represents the mass percentage of acid scavenger to flame retardant, and V2 represents the mass percentage of acid scavenger to PBT resin.

[0094] Table 1

[0095] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 PBT-1 53 35 65 53 53 53 53 53 Flame retardant 1 16 12 20 16 16 16 16 16 Hydrotalcite 0.16 0.08 0.32 0.1 0.32 0.24 / 0.2 Zinc oxide 0.08 0.04 0.16 0.05 0.16 / 0.24 0.04 Fiberglass 30 20 38 30 30 30 30 30 antioxidants 0.5 0 0.5 0.5 0.5 0.5 0.5 0.5 lubricant 0.5 0 0.5 0.5 0.5 0.5 0.5 0.5 V1 / ％ 1.5 1.0 2.4 0.9 3.0 1.5 1.5 1.5 V2 / ％ 0.5 0.3 0.7 0.3 0.9 0.5 0.5 0.5

[0096] Table 2

[0097]

[0098]

[0099] Table 3

[0100]

[0101]

[0102] The preparation method of the PBT modified material provided in Example 1 includes the following steps:

[0103] After drying, the raw materials are weighed and mixed, then fed into a twin-screw extruder. The extrusion, stranding, cooling, pelletizing, and drying processes yield PBT modified material. The feed rate of the twin-screw extruder is 500 kg / h. The screw temperatures from the feed port to the die head are 160℃, 250℃, 240℃, 230℃, 220℃, 220℃, 220℃, 220℃, 220℃, 220℃, and 220℃, respectively, and the screw speed is 450 rpm.

[0104] The preparation methods of the PBT modified materials provided in Examples 2-14 and Comparative Examples 1-7 are consistent with those in Example 1, except that the relevant components are not added.

[0105] Example of effect

[0106] The effects of this invention are explored in the examples and comparative examples, examining the properties of the PBT-modified materials prepared in the embodiments and comparative examples, specifically including the following aspects:

[0107] 1. TVOC test: The test shall be conducted in accordance with VDA277-1995, and the test conditions shall be 120℃ for 2 hours;

[0108] 2. Odor rating: The test was conducted according to PV3900. The odor rating scores are shown in Table 4. The test team consisted of 5 people. Each person's test score was taken in intervals of 0.5 points, such as 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, etc. The final test result was the average value.

[0109] Table 4

[0110] Score evaluate 1 Unable to feel 2 Perceptible, unobstructed 3 It's noticeable, but not a major hindrance. 4 Obstacles 5 It is quite a hindrance 6 Unbearable

[0111] 3. Metal Corrosion: Take equal masses (50g) of plastic granules, 10mL of ultrapure water, and metal sheets of the same cross-sectional area, and place them separately in sealed containers. The container containing the ultrapure water and the metal sheet is left open. The test condition is 85℃. The test procedure is as follows: Figure 1 As shown, the corrosion of the metal surface was observed after 6 days and classified into four levels: I, II, III, and IV. Level I indicates almost no corrosion on the metal surface; Level II indicates slight rust on the metal surface; Level III indicates spot-like corrosion on the metal surface; and Level IV indicates a larger area of ​​spot or flaky corrosion on the metal surface. Schematic diagrams of corrosion levels I, II, III, and IV are shown below. Figure 2-5 As shown;

[0112] 4. Tensile strength: Tested according to standard ISO 527-2-2012, with a sample size of 150*10*4mm and a tensile speed of 10mm / min;

[0113] 5. Flame retardancy rating: Tested according to UL 94, with a sample thickness of 0.75mm;

[0114] The results of the above performance tests are recorded in Table 5;

[0115] Table 5

[0116]

[0117] As can be seen from Table 5, when the preparation method provided by the present invention is used, the obtained PBT modified material has the characteristics of low odor, low metal corrosion and good mechanical properties in addition to having a basic flame retardant rating; specifically, the TVOC of the obtained product is below 286 μgC / g, the odor rating score is below 4.2 points, the metal corrosion rating is below Class II, and the tensile strength is above 105.5 MPa.

[0118] As can be seen from Examples 1-5 and Comparative Example 2, the mass fraction of the components and the relationship between the amounts of the components can affect the overall performance of the product to a certain extent. When the mass fraction of hydrotalcite and / or zinc oxide in Comparative Example 2 is too high, the tensile strength of the obtained product is significantly reduced, and the odor grade also shows an increasing trend.

[0119] As can be seen from Example 1 and Comparative Example 1, when no hydrotalcite and / or zinc oxide were added in Comparative Example 1, the odor rating of the obtained product decreased to 4.8 points, and the metal corrosion was level IV. As can be seen from Example 1, Examples 6-8 and Comparative Example 3, the selection of hydrotalcite and / or zinc oxide also affects the performance of the product. When hydrotalcite and zinc oxide are further contained simultaneously, the overall performance of the obtained product is better. When hydrotalcite and / or zinc oxide not used in Comparative Example 3 were not the hydrotalcite and / or zinc oxide of this invention, the odor rating of the obtained product decreased to 4.5 points, and the metal corrosion was level IV.

[0120] As can be seen from Examples 1, 9-14, and Comparative Examples 4-7, the type of flame retardant also affects the performance of the product. When the TVOC of the flame retardant in Comparative Example 4 at 180°C for 60 minutes is not within the range given in this invention, the TVOC of the obtained product increases significantly, the odor level drops to 4.5 points, and the metal corrosion is grade III. When the mass ratio of the core layer to the shell layer in the flame retardant in Comparative Example 5 is not within the range given in this invention, the metal corrosion and flame retardancy of the obtained product both deteriorate significantly. When the core layer material of the flame retardant in Comparative Example 6 is not selected in this invention, the metal corrosion of the obtained product is grade IV, and the flame retardancy is grade V-2. When no coated flame retardant is formed in Comparative Example 7, the odor level of the obtained product drops to 5.0 points, and the metal corrosion is grade IV.

[0121] Finally, it should be noted that the above embodiments are used to illustrate the technical solutions of the present invention and not to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A PBT modified material, characterized in that, The PBT modified material comprises the following components in parts by weight: 33-68 parts PBT resin, 18-40 parts glass fiber, 10-22 parts flame retardant, and 0.08-0.49 parts hydrotalcite and / or zinc oxide; The flame retardant is a core-shell structured coated flame retardant, with a core layer of melamine polyphosphate and a shell layer of diethyl aluminum hypophosphite; the mass ratio of the shell layer to the core layer is ≥1. The flame retardant has a TVOC of ≤300 μgC / g at 180℃ for 60 min.

2. The PBT modified material according to claim 1, characterized in that, The mass percentage of hydrotalcite and / or zinc oxide is ≤0.9% based on the mass of PBT resin.

3. The PBT modified material according to claim 1, characterized in that, The mass percentage of hydrotalcite and / or zinc oxide is ≥0.9% based on the mass of the flame retardant.

4. The PBT modified material according to claim 1, characterized in that, The mass ratio of the shell to the core is 1.8-5.

2.

5. The PBT modified material according to claim 1, characterized in that, The flame retardant has a TVOC of ≤280μgC / g at 180℃ for 60min.

6. The PBT modified material according to claim 1, characterized in that, The mass ratio of the hydrotalcite to zinc oxide is (1.5-6):

1.

7. The PBT modified material according to claim 1, characterized in that, The PBT modified material also includes 0.1-5 parts of processing aids.

8. The PBT modified material according to claim 7, characterized in that, The processing aids include at least one of antioxidants, lubricants, nucleating agents, laser aids, and weathering agents.

9. The method for preparing the PBT modified material according to any one of claims 1-8, characterized in that, The preparation method includes the following steps: weighing the dried raw materials and mixing them, feeding them into a twin-screw extruder, and extruding, stretching, cooling, pelletizing and drying to obtain PBT modified material.

10. The application of the PBT modified material as described in any one of claims 1-8 in the preparation of materials for the electronic, electrical, and automotive fields.

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