Polyester composite material and preparation method and application thereof

Abstract

The application provides a polyester composite material and a preparation method and application thereof, the polyester composite material comprises polybutylene terephthalate, polycarbonate, a bromine-containing flame retardant, a synergistic flame retardant and a toughening agent in specific proportions, and the bromine-containing flame retardant comprises a combination of at least two of brominated epoxy resin, brominated polycarbonate or brominated polystyrene; by selecting polybutylene terephthalate and polycarbonate for collocation, and adding at least two specific bromine-containing flame retardants and synergistic flame retardants for flame-retardant modification, the obtained polyester composite material not only has excellent flame-retardant performance, but also has a low amount of die drool when being extruded in an extruder die, thereby effectively avoiding the problem that the die drool is carbonized at high temperature and then flows into the product to contaminate the product, and effectively improving the product quality of the finally obtained polyester composite material.

Description

Technical Field

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

[0002] Polybutylene terephthalate (PBT) belongs to the polyester engineering plastic family. It possesses high mechanical strength, toughness, fatigue resistance, self-lubricating properties, outstanding chemical resistance, heat resistance, and excellent electrical properties. However, its disadvantages include low notched impact strength and high molding shrinkage. Polycarbonate resin (PC) is one of the five major engineering plastics and is an excellent thermoplastic engineering plastic widely used in electronics, automotive, medical devices, aerospace, and other fields. However, it has high melt viscosity and poor processability. Therefore, blending PC and PBT can compensate for the shortcomings of PC, such as high melt viscosity, poor flowability, and poor solvent resistance, while also improving the low impact resistance of PBT, achieving synergistic effects.

[0003] However, PC / PBT composites have poor flame retardant properties, so flame retardants are usually added to improve their flame retardancy without affecting their mechanical properties. For example, CN110885545A discloses a weather-resistant and flame-retardant PC / PBT alloy and its preparation method, comprising 50-60 parts of PC resin; 10-30 parts of PBT resin; 10-13 parts of BDP flame retardant; 1-5 parts of compatibilizer; 1-3 parts of MBS toughening agent; 0.3-0.8 parts of polytetrafluoroethylene; 0.2-0.4 parts of antioxidant; and 0.3-0.5 parts of lubricant. After drying, the PC resin, PBT resin, compatibilizer, MBS toughening agent, polytetrafluoroethylene, antioxidant, lubricant, and UV absorber are mixed with the BDP flame retardant, and then subjected to melting, extrusion, cooling, air drying, and granulation steps to obtain the PC / PBT alloy, which has good flame retardant and weather resistance properties.

[0004] However, in actual production, during the alloying process of PC and PBT, the mixed materials will precipitate at the die of the extruder. Over time, the precipitates will carbonize at high temperatures. The carbonized precipitates will flow into the product, thus contaminating the product and causing discolored particle contamination, resulting in a decline in product quality.

[0005] Therefore, developing a polyester composite material with low die exudates and excellent flame retardant properties remains a pressing technical problem to be solved in this field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a polyester composite material, its preparation method, and its application. The polyester composite material possesses excellent flame-retardant properties and exhibits low die extrusion volume and a longer carbonization time for the extruded material, thereby effectively reducing the probability of the carbonized die extruded material flowing into the product and causing contamination.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a polyester composite material, wherein the polyester composite material comprises the following components in parts by weight:

[0009]

[0010] The brominated flame retardant includes a combination of at least two of brominated epoxy resin, brominated polycarbonate, or brominated polystyrene.

[0011] The polyester composite material provided by this invention comprises a specific proportion of polybutylene terephthalate, polycarbonate, a brominated flame retardant, a synergistic flame retardant, and a toughening agent. The brominated flame retardant comprises a combination of at least two of brominated epoxy resin, brominated polycarbonate, or brominated polystyrene. On one hand, by selecting polybutylene terephthalate and polycarbonate for combination, a synergistic effect is achieved. On the other hand, flame retardant modification is performed by adding a brominated flame retardant and a synergistic flame retardant, and the brominated flame retardant is limited to a combination of at least two of brominated epoxy resin, brominated polycarbonate, or brominated polystyrene. This results in a polyester composite material that not only possesses excellent flame retardant properties but also exhibits low die extrusion. During extrusion through the extruder die, there is less die extrusion, and the discoloration of the extrusion takes a longer time. This effectively prevents the die extrusion from carbonizing at high temperatures and flowing into the product, thus contaminating it and effectively improving the quality of the final polyester composite material.

[0012] The content of polybutylene terephthalate can be 20 parts by weight, 22 parts by weight, 24 parts by weight, 26 parts by weight, 28 parts by weight, 30 parts by weight, 32 parts by weight, 34 parts by weight, 36 parts by weight, 38 parts by weight, 40 parts by weight, 42 parts by weight, 44 parts by weight, 46 parts by weight, 48 parts by weight, or 50 parts by weight, and the mass percentage of polybutylene terephthalate in the polyester composite material provided by the present invention is ≥20%.

[0013] The polycarbonate content can be 20 parts by weight, 22 parts by weight, 24 parts by weight, 26 parts by weight, 28 parts by weight, 30 parts by weight, 32 parts by weight, 34 parts by weight, 36 parts by weight, 38 parts by weight, 40 parts by weight, 42 parts by weight, 44 parts by weight, 46 parts by weight, 48 parts by weight, or 50 parts by weight, etc.

[0014] The content of the brominated flame retardant can be 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, 15 parts by weight, or 16 parts by weight, etc.

[0015] The content of the synergistic flame retardant can be 1 part by weight, 1.5 parts by weight, 2 parts by weight, 2.5 parts by weight, 3 parts by weight, 3.5 parts by weight, 4 parts by weight, 4.5 parts by weight, or 5 parts by weight, etc.

[0016] The toughening agent content can be 0.5 parts by weight, 1 part by weight, 1.5 parts by weight, 2 parts by weight, 2.5 parts by weight, 3 parts by weight, 3.5 parts by weight, or 4 parts by weight, etc.

[0017] Preferably, the melt index of the polybutylene terephthalate is ≥5 g / 10 min, such as 6 g / 10 min, 7 g / 10 min, 8 g / 10 min, 10 g / 10 min, 20 g / 10 min, 30 g / 10 min, 40 g / 10 min, 50 g / 10 min, 60 g / 10 min, 70 g / 10 min, 80 g / 10 min, 90 g / 10 min, or 100 g / 10 min, and more preferably 5 to 100 g / 10 min. The melt index is tested at 250°C and the test load is 2.16 kg.

[0018] Preferably, the intrinsic viscosity of the polybutylene terephthalate is ≥0.5 dl / g, for example, 0.6 dl / g, 0.7 dl / g, 0.8 dl / g, 0.9 dl / g, 1 dl / g, 1.1 dl / g, 1.2 dl / g, 1.3 dl / g, 1.4 dl / g, 1.5 dl / g, 2 dl / g, 3 dl / g, 4 dl / g, 5 dl / g, 6 dl / g, 7 dl / g, 8 dl / g, 9 dl / g, or 10 dl / g, and more preferably 0.5 to 10 dl / g, and the intrinsic viscosity is tested at 25°C.

[0019] Preferably, the polycarbonate has a melt index ≤15g / 10min, such as 14g / 10min, 13g / 10min, 12g / 10min, 10g / 10min, 9g / 10min, 8g / 10min, 7g / 10min, 6g / 10min, 5g / 10min, 4g / 10min, 3g / 10min, 2g / 10min, or 1g / 10min, etc., and the melt index is tested at a temperature of 300℃ and the test load is 1.2kg.

[0020] In this invention, the melt index of both the polybutylene terephthalate and the polycarbonate can be tested according to the method provided in ISO 1133-1:2022.

[0021] In this invention, the intrinsic viscosity of the polybutylene terephthalate is tested according to the capillary viscometer method in the standard GB / T 14190-2008.

[0022] Preferably, the brominated flame retardant is a combination of brominated epoxy resin and brominated polycarbonate, wherein the mass ratio of the brominated epoxy resin to the brominated polycarbonate is 1:(0.05-20), for example 1:0.05, 1:0.1, 1:0.5, 1:1, 1:2, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18, 1 or 20, etc., and more preferably 1:(0.1-10).

[0023] Preferably, the brominated flame retardant is a combination of brominated epoxy resin and brominated polystyrene, wherein the mass ratio of the brominated epoxy resin to the brominated polystyrene ester is 1:(0.05-20), for example 1:0.05, 1:0.1, 1:0.5, 1:1, 1:2, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18, 1 or 20, and more preferably 1:(0.1-10).

[0024] Preferably, the brominated flame retardant is a combination of brominated polycarbonate and brominated polystyrene, wherein the mass ratio of brominated polycarbonate to brominated polystyrene is 1:(0.05-20), for example 1:0.05, 1:0.1, 1:0.5, 1:1, 1:2, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18, 1 or 20, etc., and more preferably 1:(0.1-10).

[0025] The present invention further limits the mass ratio of any two bromine-containing flame retardants in the bromine-containing flame retardant to the above-mentioned specific range, which can further reduce the amount of die leaching of the final polyester composite material, prolong the time for the leaching to change color, and further reduce the problem of product contamination caused by carbonization of die leaching, thereby improving the quality of the final polyester composite material.

[0026] Preferably, the brominated flame retardant comprises a combination of brominated epoxy resin, brominated polycarbonate and brominated polystyrene, and the mass ratio of any two of the brominated epoxy resin, brominated polycarbonate and brominated polystyrene is 1:(0.05-20), more preferably 1:(0.1-10);

[0027] The mass ratio of the brominated epoxy resin to the brominated polycarbonate can be 1:0.05, 1:0.1, 1:0.5, 1:1, 1:2, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18, or 1:20, etc., and the mass ratio of the brominated epoxy resin to the brominated polystyrene can be 1:0.05, 1:0.1, 1:0.5, 1:1, etc. The mass ratio of the brominated polystyrene to the brominated polycarbonate can be 1:2, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18, or 1:20, etc.

[0028] The present invention further selects the above three different types of bromine-containing flame retardants for compounding. The three synergistic effects can further improve the flame retardant properties of the obtained polyester composite material, further reduce its extrusion amount at the die head of the extruder, and further improve the quality of the product.

[0029] Preferably, the weight-average molecular weight of the brominated epoxy resin is ≥5000, such as 5000, 6000, 7000, 8000, 9000, 10000, 12000, 14000, 15000, 16000, 17000, 18000, 19000, 20000, 21000, 22000, 23000, 24000 or 25000, more preferably ≥6000, and even more preferably 6000 to 30000.

[0030] Preferably, the brominated polycarbonate has a weight-average molecular weight of ≥3000, such as 3000, 4000, 4100, 4200, 4300, 4400, 4500, 4600, 4700, 4800, 4900, 5000, 5200, 5400, 5600, 5800 or 6000, more preferably ≥4000, and even more preferably 4000 to 8000.

[0031] Preferably, the weight-average molecular weight of the brominated polystyrene is ≥5000, such as 5000, 5500, 6000, 6500, 7000, 9000, 10000, 50000, 100000, 200000, 400000 or 600000, more preferably ≥7000, and even more preferably 7000 to 700000.

[0032] In this invention, the weight-average molecular weights of the brominated epoxy resin, brominated polycarbonate, and brominated polystyrene were all obtained by gel permeation chromatography.

[0033] Preferably, the synergistic flame retardant comprises antimony trioxide.

[0034] Preferably, the toughening agent comprises any one or a combination of at least two of the following: ethylene-acrylate-glycidyl methacrylate copolymer, ethylene-acrylate copolymer, ethylene-vinyl acetate copolymer, methacrylate-styrene-silicone copolymer, or methacrylate-styrene-butadiene copolymer.

[0035] In a second aspect, the present invention provides a method for preparing a polyester composite material as described in the first aspect, the method comprising: mixing polybutylene terephthalate, polycarbonate, a bromine-containing flame retardant, a synergistic flame retardant and a toughening agent, and extruding and granulating the mixture in an extruder to obtain the polyester composite material.

[0036] Preferably, the brominated flame retardant is obtained by mixing brominated epoxy resin, brominated polycarbonate and brominated polystyrene.

[0037] Preferably, the mixing time is 2 to 5 minutes, such as 2 minutes, 2.5 minutes, 3 minutes, 3.5 minutes, 4 minutes, 4.5 minutes, or 5 minutes.

[0038] Preferably, the extruder is a single-screw extruder.

[0039] Preferably, the extrusion temperature of the single-screw extruder is 200-300℃, such as 200℃, 220℃, 240℃, 260℃, 270℃, 280℃, 290℃ or 300℃.

[0040] Thirdly, the present invention provides an application of the polyester composite material as described in the first aspect in the fields of electronics and electrical engineering, automotive industry, medical devices, or aerospace.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] (1) The polyester composite material provided by the present invention includes a specific number of polybutylene terephthalate, polycarbonate, brominated flame retardant, synergistic flame retardant and toughening agent, and the brominated flame retardant includes a combination of at least two of brominated epoxy resin, brominated polycarbonate or brominated polystyrene; by selecting polybutylene terephthalate and polycarbonate for combination, and adding at least two specific brominated flame retardants and synergistic flame retardants for flame retardant modification, the resulting polyester composite material not only has excellent mechanical properties and flame retardant properties, but also has a low amount of die precipitate at the extruder die head, thereby effectively avoiding the problem of the die precipitate carbonizing at high temperature and flowing into the product to contaminate the product, and effectively improving the quality of the final polyester composite material;

[0043] (2) Specifically, the polyester composite material provided by the present invention has a die precipitate weight of only 0.125 to 0.230 g, the precipitate takes 10 to 17 minutes to change color, and the flame retardant rating can reach V-0 level. Detailed Implementation

[0044] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0045] The following is some information about the raw materials used in the examples and comparative examples:

[0046] (1) Polybutylene terephthalate (PBT)

[0047] PBT-1: Melt index of 8 g / 10 min, purchased from Sinopec Yizheng Chemical Fiber Co., Ltd., grade GL236;

[0048] PBT-2: Melt index of 30g / 10min, purchased from Sinopec Yizheng Chemical Fiber Co., Ltd., grade PBT-GX121;

[0049] PBT-3: Melt index of 65 g / 10 min, purchased from Sinopec Yizheng Chemical Fiber Co., Ltd., grade PBT-GX112.

[0050] (2) Polycarbonate (PC)

[0051] PC-1: Melt index of 3.9 g / 10 min, purchased from Mitsubishi Engineering Plastics Corporation (Mitsubishi Chemical), grade PC7030PJ;

[0052] PC-1: Melt index of 10 g / 10 min, purchased from LG Chem, grade PC 1300-10NP.

[0053] (3) Bromine-containing flame retardants

[0054] (A) Brominated epoxy resin

[0055] A1: Weight average molecular weight is 24,000, purchased from Shandong Tianyi Chemical Co., Ltd., grade Z-52;

[0056] A2: Weight average molecular weight is 20,000, purchased from the Dead Sea in Israel, grade F-2100 powder;

[0057] A3: Weight average molecular weight is 15,000, purchased from Changchun Artificial Resin Factory Co., Ltd., brand name is BEB-6000.

[0058] A4: Weight average molecular weight is 5500, purchased from Suzhou Boruida, brand name CR-100K.

[0059] (B) Brominated polycarbonate

[0060] B1: Weight average molecular weight is 4500, purchased from Teijin, Japan, brand name FG8500;

[0061] B2: Weight average molecular weight is 4000, purchased from Teijin, Japan, brand name FG7500;

[0062] B3: Weight average molecular weight is 3500, purchased from Lanxess, brand name is powder BC-58.

[0063] (C) Brominated polystyrene

[0064] C1: Weight average molecular weight is 600,000, purchased from Shandong Brothers, brand name BPS-3010.

[0065] C2: Weight average molecular weight is 200,000, purchased from Shandong Xiongdi, brand name is XZ-6700;

[0066] C3: Weight average molecular weight is 13,500, purchased from Albemarle, USA, brand name HP-3010PST;

[0067] C4: Weight average molecular weight is 6000, purchased from Albemarle, USA, brand name HP-5010PST.

[0068] (5) Synergistic flame retardants

[0069] Antimony trioxide: purchased from Yiyang Shengli Materials, grade S-04N.

[0070] (6) Toughening agent

[0071] Ethylene-acrylate copolymer, purchased from DuPont, brand name Elvaloy resins PTW.

[0072] Examples 1-19 and Comparative Examples 1-9

[0073] Examples 1-19 and Comparative Examples 1-9 each provide a polyester composite material, the components and amounts of which are shown in Tables 1-3;

[0074] In Tables 1-3, the dosage range for each component is in "parts by weight";

[0075] Table 1

[0076]

[0077] Table 2

[0078]

[0079]

[0080] Table 3

[0081]

[0082] The preparation methods of the polyester composite materials provided in Examples 1-19 and Comparative Examples 1-9 include: mixing polybutylene terephthalate, polycarbonate, a brominated flame retardant (obtained by mixing brominated epoxy resin, brominated polycarbonate and brominated polystyrene), a synergistic flame retardant and a toughening agent for 3 min, extruding in a single-screw extruder at an extrusion temperature of 270°C and an extrusion frequency of 40 Hz, and then granulating and drying to obtain the polyester material.

[0083] Performance testing:

[0084] (1) Die precipitates: Extrusion was carried out using a single screw extruder at an extrusion temperature of 270℃, with an experimental weight of 10kg and an extrusion frequency of 40Hz. The time it took for the die precipitates to change color (carbonize) was recorded, and the precipitates were collected and weighed.

[0085] (3) Flame retardant performance: tested in accordance with UL94 standard.

[0086] The polyester composite materials provided in Examples 1-19 and Comparative Examples 1-9 were tested according to the above test methods, and the test results are shown in Table 4:

[0087] Table 4

[0088]

[0089]

[0090] According to the data in Table 4:

[0091] The polyester composite material provided by this invention has low die exudation and excellent flame retardant properties, as detailed below:

[0092] (1) The weight of the die precipitate of the polyester composite materials obtained in Examples 1 to 19 was 0.125 to 0.230 g, the time for the precipitate to change color was 10 to 17 min, and the flame retardant rating could reach V-0 level.

[0093] Among them, the polyester composite materials provided in Examples 1-5, Examples 12-13, Examples 15 and Examples 17-18 have an exudate weight of only 0.125-0.156g, the time for the exudate to change color is as long as 14-17min, and the flame retardant rating can reach V-0 level. The die exudation and flame retardancy are both optimal.

[0094] (2) Compared with Example 1, the relative amount of polybutylene terephthalate in the polyester composite materials provided by Comparative Examples 1 and 2 is too low or too high, which will lead to an increase in the amount of precipitates in the die and a shorter time for the precipitates to change color. This will make it easier for the carbonized precipitates to flow into the product and affect the product quality.

[0095] (3) Compared with Example 1, the total amount of brominated flame retardant added to the polyester composite material provided by Comparative Example 3 was lower, which not only led to an increase in die precipitates, but also to a significant decrease in flame retardant performance; while the total amount of brominated flame retardant added to the polyester composite material provided by Comparative Example 4 was too high, which did not further improve the flame retardant performance, but instead led to an increase in die precipitates, affecting product quality.

[0096] (4) Compared with Example 1, the polyester composite materials provided in Comparative Examples 5 to 7 all use a single type of bromine-containing flame retardant, which has little effect on flame retardant performance, but will lead to a significant increase in precipitates in the die and a significant shortening of the time for the precipitates to change color, which seriously affects product quality.

[0097] (5) Compared with Example 1, the polyester composite materials provided in Comparative Examples 8 and 9 did not contain any bromine-containing flame retardant or synergistic flame retardant, resulting in flame retardant ratings of only HB and V-2, and poor flame retardancy.

[0098] The applicant declares that this invention illustrates a polyester composite material, its preparation method, and its application through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the product, additions of auxiliary components, and selection of specific methods all fall within the protection and disclosure scope of this invention.

Claims

1. A polyester composite material, characterized in that, The polyester composite material comprises the following components in parts by weight: 20-50 parts by weight of polybutylene terephthalate; 20-50 parts by weight of polycarbonate; 10-16 parts by weight of brominated flame retardant; 1-5 parts by weight of synergistic flame retardant; Toughening agent 0.5~4 parts by weight; The brominated flame retardant is a combination of brominated epoxy resin, brominated polycarbonate and brominated polystyrene, wherein the mass ratio of any two of the brominated epoxy resin, brominated polycarbonate and brominated polystyrene is 1:(0.05~20). Alternatively, the brominated flame retardant is a combination of brominated epoxy resin and brominated polycarbonate, wherein the mass ratio of the brominated epoxy resin to the brominated polycarbonate is 1:(0.05~2); Alternatively, the brominated flame retardant is a combination of brominated epoxy resin and brominated polystyrene, wherein the mass ratio of the brominated epoxy resin to the brominated polystyrene ester is 1:(0.05~2); Alternatively, the brominated flame retardant is a combination of brominated polycarbonate and brominated polystyrene, wherein the mass ratio of brominated polycarbonate to brominated polystyrene is 1:(0.05~2).

2. The polyester composite material according to claim 1, characterized in that, The polybutylene terephthalate has a melt index ≥ 5 g / 10 min.

3. The polyester composite material according to claim 1, characterized in that, The polycarbonate has a melt index of ≤15g / 10min.

4. The polyester composite material according to claim 1, characterized in that, The brominated flame retardant is a combination of brominated epoxy resin, brominated polycarbonate and brominated polystyrene, wherein the mass ratio of any two of the brominated epoxy resin, brominated polycarbonate and brominated polystyrene is 1:(0.1~10).

5. The polyester composite material according to claim 1, characterized in that, The weight-average molecular weight of the brominated epoxy resin is ≥5000.

6. The polyester composite material according to claim 5, characterized in that, The weight-average molecular weight of the brominated epoxy resin is ≥6000.

7. The polyester composite material according to claim 1, characterized in that, The brominated polycarbonate has a weight-average molecular weight ≥3000.

8. The polyester composite material according to claim 7, characterized in that, The brominated polycarbonate has a weight-average molecular weight ≥ 4000.

9. The polyester composite material according to claim 1, characterized in that, The brominated polystyrene has a weight-average molecular weight ≥ 5000.

10. The polyester composite material according to claim 9, characterized in that, The weight-average molecular weight of the brominated polystyrene is ≥7000.

11. The polyester composite material according to claim 1, characterized in that, The synergistic flame retardant includes antimony trioxide.

12. The polyester composite material according to claim 1, characterized in that, The toughening agent includes any one or a combination of at least two of the following: ethylene-acrylate-glycidyl methacrylate copolymer, ethylene-acrylate copolymer, ethylene-vinyl acetate copolymer, methacrylate-styrene-silicone copolymer, or methacrylate-styrene-butadiene copolymer.

13. A method for preparing a polyester composite material according to any one of claims 1 to 12, characterized in that, The preparation method includes: mixing polybutylene terephthalate, polycarbonate, bromine-containing flame retardant, synergistic flame retardant and toughening agent, and extruding and granulating them in an extruder to obtain the polyester composite material.

14. The preparation method according to claim 13, characterized in that, The mixing time is 2 to 5 minutes.

15. The preparation method according to claim 13, characterized in that, The extruder is a single-screw extruder.

16. The preparation method according to claim 15, characterized in that, The extrusion temperature of the single-screw extruder is 200~300℃.

17. The use of a polyester composite material as described in any one of claims 1 to 12 in the electronics, automotive, or aerospace industries.

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