Flame-retardant polycarbonate composition as well as preparation method and application thereof

Abstract

The invention belongs to the field of plastic materials, and particularly discloses a flame-retardant polycarbonate composition as well as a preparation method and application thereof. The flame-retardant polycarbonate composition disclosed by the invention is prepared from the following components in parts by weight: 89 to 101 parts of polycarbonate, 0.4 to 5.5 parts of phenyl-containing siloxane, 0.4 to 1 part of an elastomer with a core-shell structure, 0.05 to 0.2 part of a sulfonate flame retardant, 0.05 to 0.2 part of an inhibitor, 0.1 to 1.1 parts of an anti-dripping agent and 0 to 3.1 parts of a processing aid. The core-shell structure elastomer and the inhibitor can improve the material appearance defect, and meanwhile, the sulfonate flame retardant and the phenyl-containing siloxane play a good flame retardant synergistic effect, so that the flame retardant property is improved. Besides, the sulfonate flame retardant in the system has small influence on the heat resistance of the polycarbonate, so that the composition can still maintain high heat resistance, and the flame-retardant polycarbonate composition has the advantages of good appearance, high heat resistance and high flame retardance under the comprehensive action.

Description

Technical Field

[0001] The invention belongs to the field of plastics, and in particular relates to a flame retardant polycarbonate composition and a preparation method and application thereof. Background Art

[0002] Polycarbonate has excellent properties such as high strength, high toughness, high heat resistance, good dimensional stability and electrical insulation, and has been widely used in home appliances, medical equipment, electrical and electronic fields. In particular, when polycarbonate is used in electrical and electronic fields, it is usually required to have good halogen-free flame retardancy, heat resistance and good appearance to meet people's high quality requirements for new electrical and electronic products.

[0003] In the prior art, the requirements for halogen-free flame retardancy of polycarbonate are met by adding aromatic phosphate flame retardants or sulfonate flame retardants. However, aromatic phosphate flame retardants will significantly affect the heat resistance of polycarbonate, resulting in its inability to meet the heat resistance requirements. Although a small amount of sulfonate flame retardant added to the system has little effect on the heat resistance of polycarbonate, the material can achieve good heat resistance; however, the amount of sulfonate flame retardant is small, and it is difficult to stably achieve thin-wall (such as a sample thickness of 1.6 mm) flame retardant performance. In addition, the property of sulfonate flame retardants that catalyzes the degradation of polycarbonate into carbon makes it very easy to have material problems during processing, resulting in poor appearance of the product.

[0004] Therefore, there is still a need to further study and improve the polycarbonate composition to obtain a halogen-free flame retardant polycarbonate product that meets both good appearance and high heat resistance. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the polycarbonate materials in the prior art that cannot have both good appearance, high heat resistance and halogen-free flame retardancy. The present invention will provide a flame retardant polycarbonate composition and a preparation method and application thereof.

[0006] To achieve the above purpose, the following technical solutions are specifically included:

[0007] On the one hand, the present invention provides a flame retardant polycarbonate composition, comprising the following components in parts by weight: polycarbonate 89-101, 0.4-5.5 parts of phenyl siloxane, 0.4-1 parts of core-shell structure elastomer, 0.05-0.2 parts of sulfonate flame retardant, 0.05-0.2 parts of inhibitor, 0.1-1.1 parts of anti-dripping agent, and 0-3.1 parts of processing aid; the inhibitor comprises at least one of a lactone carbon free radical scavenger and a bisphenol monoacrylate antioxidant.

[0008] In the flame retardant polycarbonate composition of the present invention, the core-shell structure elastomer can inhibit the catalytic degradation effect of the sulfonate flame retardant on the polycarbonate during processing, and at the same time, the inhibitor can inhibit the catalytic degradation effect of the sulfonate flame retardant on the core-shell structure elastomer during the preparation process and the self-crosslinking effect of the core-shell structure elastomer, so the flame retardant polycarbonate composition effectively improves the appearance of the product on the basis of maintaining its flame retardant properties. At the same time, the phenyl-containing siloxane in the system, as a silicon-based flame retardant, plays a good flame retardant synergistic role with the sulfonate flame retardant, avoiding the flame retardant degradation effect of the core-shell structure elastomer on the material, thereby ensuring good flame retardant properties. In addition, because the core-shell structure elastomer can inhibit the catalytic degradation effect of the sulfonate flame retardant on the polycarbonate during processing, it has less effect on the heat resistance of the polycarbonate and is more environmentally friendly without halogen, so the composition can still maintain a high heat resistance. Under the comprehensive effect, the flame retardant polycarbonate composition can simultaneously achieve good appearance, high heat resistance and high flame retardancy.

[0009] Preferably, the flame retardant polycarbonate composition comprises the following components in parts by weight: 90-100 parts of polycarbonate, 0.5-5 parts of phenyl siloxane, 0.5-0.9 parts of core-shell structure elastomer, 0.07-0.17 parts of sulfonate flame retardant, 0.07-0.17 parts of inhibitor, 0.2-1 parts of anti-drip agent, and 0-3 parts of processing aid. Preferably, in the flame retardant polycarbonate composition, the mass percentage of the polycarbonate (PC) is not less than 70%, more preferably not less than 80%, and even more preferably not less than 90%.

[0010] Preferably, the system of the present invention has no restriction on the type of polycarbonate. The polycarbonate is preferably bisphenol A polycarbonate. Commercially available conventional polycarbonate can be used, and homemade polycarbonate can also be used. For example, polycarbonate with a melt mass flow rate of 1-60 g / 10 min can be used, wherein the melt mass flow rate is tested according to ISO 1133-1 2011 standard, and the test conditions are 300°C and 1.2 kg. More specifically, the melt mass flow rate of the polycarbonate can be 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 g / 10 min, etc., as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0011] Preferably, the core-shell structure elastomer includes at least one of MBS (methyl methacrylate-butadiene-styrene terpolymer) and ABS.

[0012] ABS is a terpolymer of acrylonitrile-butadiene-styrene, and includes ABS for resin and ABS high-rubber powder. The contents of acrylonitrile, butadiene and styrene in ABS for resin are 25%-30%, 20%-35% and 40%-50% respectively. The content of butadiene in ABS high-rubber powder is between 60%-80%.

[0013] Further preferably, the rubber content of the MBS is 50%-70%.

[0014] More preferably, the rubber content of the ABS used in the resin is 20%-35%.

[0015] Further preferably, the rubber content of the ABS is 55%-80%.

[0016] Preferably, the sulfonate flame retardant includes at least one of potassium perfluorobutylsulfonate and potassium benzenesulfonylbenzenesulfonate.

[0017] Preferably, the chemical structure of the lactone carbon free radical scavenger is as shown in Formula I or Formula II below:

[0018]

[0019] In Formula I, R1, R2, R3 and R4 may be the same or different, and represent a hydrogen atom or a straight or branched alkyl group having 1 to 8 carbon atoms, R5, R6, R8 and R9 may be the same or different, and represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, R7 represents a hydrogen atom or a hydroxyl group, and n is an integer of 0, 1, 2 or 2;

[0020]

[0021] In formula II, R1, R2, R3 and R4 may be the same or different and represent a hydrogen atom or a straight or branched chain alkyl group having 1 to 8 carbon atoms.

[0022] More preferably, the lactone carbon radical scavenger comprises

[0023]

[0024] Preferably, the chemical structural formula of the bisphenol monoacrylate antioxidant is as follows:

[0025]

[0026] In formula III, R1, R2, R3, R4 and R5 may be the same or different and represent a hydrogen atom or a straight or branched chain alkyl group having 1 to 8 carbon atoms.

[0027] More preferably, the bisphenol monoacrylate antioxidant includes

[0028]

[0029] Preferably, the mass ratio of the core-shell structure elastomer, the sulfonate flame retardant and the inhibitor is 1:(0.09-0.22):(0.09-0.22), and further preferably, the mass ratio of the core-shell structure elastomer, the sulfonate flame retardant and the inhibitor is 1:(0.09-0.16):(0.16-0.20), and specifically can be 1:0.09:0.09, 1:0.09:0.15, 1:0.09:0.22, 1:0.15:0.09, 1:0.22:0.15, 1:0.22:0.22, etc., as well as specific point values ​​between the above point values. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the said range.

[0030] Preferably, the phenyl-containing siloxane includes at least one of polyaminopropylphenylsilsesquioxane, phenylsilsesquioxane and polyphenylmethylsiloxane.

[0031] Preferably, the number average molecular weight of the phenyl-containing siloxane is 400-30000 g / mol.

[0032] Compared with phenyl-free siloxanes, phenyl-containing siloxanes have better compatibility with the system, can further improve appearance defects, and have better flame retardant properties. The phenyl-containing siloxanes in the above range can achieve better flame retardant and appearance improvement effects.

[0033] Preferably, the anti-drip agent comprises polytetrafluoroethylene.

[0034] Preferably, the processing aid comprises the following components in parts by weight: 0.1-1.5 parts of antioxidant and 0.1-1.5 parts of lubricant.

[0035] More preferably, the antioxidant is a hindered phenol antioxidant.

[0036] On the other hand, the present invention provides a method for preparing the flame retardant polycarbonate composition, comprising the following steps: mixing, melting, extruding and granulating the raw materials in sequence to obtain the flame retardant polycarbonate composition.

[0037] Preferably, the melting temperature is 210-250°C.

[0038] Preferably, the rotation speed during melting is 200 to 600 rpm.

[0039] The present invention also provides an application of the flame retardant polycarbonate composition in the preparation of electronic and electrical equipment such as a charger housing and a mobile power supply housing.

[0040] Compared with the prior art, the present invention has the following beneficial effects: the flame retardant polycarbonate composition of the present invention can improve the material appearance defects, and at the same time, it has a good flame retardant synergistic effect with phenyl-containing siloxane to improve the flame retardant performance. In addition, the sulfonate flame retardant in the flame retardant polycarbonate composition has little effect on the heat resistance of polycarbonate, so the composition can still maintain a high heat resistance. Under the comprehensive effect, the flame retardant polycarbonate composition has the advantages of good appearance, high heat resistance and high flame retardancy. DETAILED DESCRIPTION

[0041] In order to better illustrate the purpose, technical scheme and advantages of the present invention, the present invention will be further described below through specific examples. The test methods used in the examples and / or comparative examples are conventional methods unless otherwise specified; the materials, reagents, etc. used can be obtained from commercial channels unless otherwise specified. The components and raw materials used in the examples and comparative examples of the present invention are the same unless otherwise specified.

[0042] The raw material information involved in the following examples and comparative examples:

[0043] PC resin: PC 1300 10NP, LG Chemical Co., Ltd., South Korea;

[0044] Sulfonate flame retardant: potassium perfluorobutyl sulfonate, FR-2025, 3M, USA;

[0045] Core-shell structure elastomer 1: MBS, M-521, Japan Zhongyuan;

[0046] Core-shell structure elastomer 2: ABS resin, ABS275, Takahashi Petrochemical;

[0047] Core-shell structure elastomer 3: ABS high rubber powder, HR181, Kumho, South Korea;

[0048] Non-core-shell elastomer: Elvaloy resins PTW, DuPont;

[0049] Inhibitor 1: Revonox 501, CAS: 1261240-30-5, lactone carbon radical scavenger, Chi Tai Chemical, Taiwan, China;

[0050] Inhibitor 2: GS, CAS: 123968-25-2, bisphenol monoacrylate antioxidant, Qingdao Jiedejia;

[0051] Inhibitor 3: HP136, CAS: 181314-48-7, lactone carbon radical scavenger, BASF;

[0052] Hydroxylamine carbon radical scavenger: Revonox 420, Qitai Chemical, Taiwan, China;

[0053] Phenyl siloxane 1: polyphenyl methyl siloxane, CAS No. 63148-52-7, Sigma-Aldrich Company;

[0054] Phenyl siloxane 2: octaphenyl silsesquioxane, CAS No. 5256-79-1, Sigma-Aldrich Company;

[0055] Phenyl-free siloxane: polydimethylsiloxane (phenyl-free), CAS No. 9016-00-6, Sigma-Aldrich Company;

[0056] Anti-drip agent: polytetrafluoroethylene, A3800, Mitsubishi Rayon;

[0057] Antioxidant: Hindered phenol antioxidant, Antioxidant 1010, Sanfeng Chemical Co., Ltd.

[0058] Examples 1-13 and Comparative Examples 1-8

[0059] A method for preparing a flame retardant polycarbonate composition comprises the following steps:

[0060] (1) According to the amounts of raw material components in Tables 1 and 2, the components were stirred and blended in a high-speed mixer to obtain a premix;

[0061] (2) feeding the premix into a twin-screw extruder through a main feeding port, melt-mixing and extruding granulation in the twin-screw extruder to obtain the flame-retardant polycarbonate composition, wherein the screw aspect ratio is 45:1, the barrel temperature is 210-250° C., and the screw speed is 550 rpm.

[0062] The testing methods for various properties of the flame retardant polycarbonate compositions of the embodiments of the present invention and the comparative examples are as follows:

[0063] (1) Flame retardant grade: The flammability test is carried out in accordance with the "Flammability Test of Plastic Materials, UL94-2019" regulations. The flame retardant grade is derived based on the burning rate, extinguishing time, ability to resist dripping, and whether the dripping is burning. The sample used for the test: 125mm long, 13mm wide, the thickness of the present invention is selected as 1.6mm during the test. According to the UL94-2019 regulations, the flame retardant grade of the material can be classified as UL94 V0, V1, V2, etc.; the flame retardant grade of V-1 or above is considered qualified;

[0064] (2) Ball pressing temperature: The pellets of the above-mentioned embodiments and comparative examples were injection molded into disc specimens with a thickness of 4 mm and a diameter of 40 mm. The indentation diameter at a ball pressing temperature of 125° C. was tested according to the IEC60695-10-2 standard method. If the indentation diameter was ≤ 2 mm, it was judged to have passed the 125° C. ball pressing temperature. If the indentation diameter was > 2 mm, it was judged to have failed.

[0065] (3) Appearance evaluation: The pellets of the above-mentioned embodiments and comparative examples were injection molded into samples and retained at 300° C. for 5 min. They were then injection molded into samples of 80*20*4 mm. The surface flower patterns of the samples were then observed. The ratio of the flower pattern area to the surface area of ​​the samples was X. The samples were recorded as excellent (X=0%), good (X≤5%), qualified (5%<X≤15%), and unqualified (X>15%) according to the size of the flower pattern area. The test results are shown in Table 3.

[0066] Table 1 Flame retardant polycarbonate composition (parts by weight)

[0067]

[0068]

[0069] Table 2 Flame retardant polycarbonate composition (parts by weight)

[0070]

[0071] Table 3

[0072]

[0073]

[0074] From the above examples, it can be seen that the flame retardant polycarbonate composition of the present invention has a 1.6 mm thick sample with a V-1 flame retardant grade or above, a 125°C ball pressure test diameter of less than 2 mm, a qualified appearance, and excellent flame retardancy, heat resistance and appearance.

[0075] In Comparative Example 1, no inhibitor and core-shell structure elastomer are added, and only a high content of pure sulfonate flame retardant is added to achieve a better flame retardant effect. However, the flame retardant has a certain influence on the heat resistance of PC, and the flame retardant catalyzes the degradation of PC, resulting in poor heat resistance and appearance performance; in Comparative Example 2, too much sulfonate flame retardant, inhibitor and core-shell structure elastomer are added. Although the flame retardant content is sufficient, there are too many core-shell structure elastomers in the system, which is not conducive to flame retardancy, resulting in a decrease in flame retardant performance. In addition, due to the excessive flame retardant in the system, the catalytic degradation of the sulfonate flame retardant The degree of polycarbonate degradation is high, resulting in poor appearance performance; the comparative example 5 lacks an inhibitor, and cannot inhibit the catalytic degradation effect and the self-crosslinking effect of the core-shell structure elastomer, resulting in poor appearance performance; the comparative example 6 lacks a core-shell structure elastomer, and cannot inhibit the catalytic degradation effect of the sulfonate flame retardant on the polycarbonate during processing, resulting in poor appearance performance; It can be seen from Example 1 and comparative examples 1-2, 5-6 that adding a certain amount of sulfonate flame retardant, inhibitor and core-shell structure elastomer to PC can make the carbonate composition have the characteristics of high heat resistance, high flame retardancy and good appearance.

[0076] It can be seen from Examples 1-2 and Comparative Examples 7-8 that Comparative Example 7 does not contain phenyl-containing siloxane, and Comparative Example 8 does not add phenyl-containing siloxane. The flame retardant properties and appearance properties of Comparative Examples 7-8 deteriorate, and phenyl-containing siloxane can further improve the flame retardant properties and appearance defects.

[0077] In Examples 1 and 5-7, the total weight portions of the core-shell elastomer, the sulfonate flame retardant and the inhibitor are the same, but the weight portions of the core-shell elastomer, the sulfonate flame retardant and the inhibitor are (1:0.16:0.16), (1:0.09:0.22), (1:0.12:0.20) and (1:0.22:0.09), respectively. As the content of the sulfonate flame retardant increases, the content of the inhibitor decreases, the flame retardant performance of the material improves, and the appearance performance shows a downward trend. When the weight portion ratio of the core-shell elastomer, the sulfonate flame retardant and the inhibitor is maintained in the range of 1:(0.09-0.22):(0.09-0.22), the flame retardant and appearance performance of the material are relatively excellent. It is further preferred that the weight portion ratio of the core-shell elastomer, the sulfonate flame retardant and the inhibitor is 1:(0.09-0.16):(0.16-0.20), and the flame retardant and appearance performance of the material are better.

[0078] In Examples 8, 1, and 9, the weight ratio of the sulfonate flame retardant to the inhibitor is 1:1, but the total weight of the two is 0.14 parts, 0.24 parts, and 0.3 parts, respectively. It can be observed that with the increase of the sulfonate flame retardant content in the system, the flame retardant performance shows an upward trend, and the appearance performance shows a downward trend. Therefore, in the system, it is more appropriate to maintain the weight of the sulfonate flame retardant or inhibitor at 0.07-0.17, which can make the flame retardant performance and appearance performance better at the same time.

[0079] The inhibitors in Examples 1 and 10-11 are respectively lactone carbon radical scavengers and bisphenol monoacrylate antioxidants, and have excellent flame retardant and appearance effects; Comparative Example 5 does not add inhibitors, and has poor flame retardant and appearance properties; Comparative Example 3 uses hydroxylamine carbon radical scavengers to replace an equal amount of inhibitors, and has poor appearance properties; It can be seen that the present invention selects specific types of inhibitors to inhibit the catalytic degradation effect of sulfonate flame retardants on core-shell structure elastomers and the self-crosslinking effect of core-shell structure elastomers during the preparation process, thereby effectively improving the appearance of the material flower phenomenon of the product while maintaining its flame retardant properties.

[0080] In Examples 1, 12-13, the core-shell elastomers are MBS, ABS for resin, and ABS high-rubber powder, respectively. When MBS is used, both the flame retardancy and appearance are optimal. Compared with MBS, the appearance performance is slightly worse when ABS is used, and the flame retardancy is slightly worse when high-rubber powder is used; therefore, MBS is preferred for the above three core-shell elastomers. Meanwhile, although the same amount of elastomer is added in Comparative Example 4, it is not a core-shell structure, and its flame retardancy and appearance performance cannot meet the requirements.

[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A flame retardant polycarbonate composition, characterized in that: The composition comprises the following components in parts by weight: Polycarbonate 89-101 contains 0.4-5.5 parts of phenyl siloxane, 0.5-1 parts of core-shell structure elastomer, 0.05-0.2 parts of sulfonate flame retardant, 0.05-0.2 parts of inhibitor, 0.1-1.1 parts of anti-dripping agent and 0-3.1 parts of processing aid; the inhibitor comprises at least one of lactone carbon free radical scavenger and bisphenol monoacrylate antioxidant.

2. The flame retardant polycarbonate composition according to claim 1, characterized in that The core-shell structure elastomer includes at least one of MBS and ABS.

3. The flame retardant polycarbonate composition according to claim 1, characterized in that The sulfonate flame retardant includes at least one of potassium perfluorobutyl sulfonate and potassium benzenesulfonylbenzenesulfonate.

4. The flame retardant polycarbonate composition according to claim 1, characterized in that The mass ratio of the core-shell structure elastomer, the sulfonate flame retardant and the inhibitor is 1:(0.09-0.22):(0.09-0.22).

5. The flame retardant polycarbonate composition according to claim 4, characterized in that The mass ratio of the core-shell structure elastomer, the sulfonate flame retardant and the inhibitor is 1:(0.09-0.16):(0.16-0.20).

6. The flame retardant polycarbonate composition according to claim 1, characterized in that The phenyl-containing siloxane includes at least one of polyaminopropylphenylsilsesquioxane, phenylsilsesquioxane, and polyphenylmethylsiloxane.

7. The flame retardant polycarbonate composition according to claim 1, characterized in that The anti-drip agent includes polytetrafluoroethylene.

8. The flame retardant polycarbonate composition according to claim 1, characterized in that The processing aid comprises the following components in parts by weight: 0.1-1.5 parts of antioxidant and 0.1-1.5 parts of lubricant.

9. A method for preparing the flame retardant polycarbonate composition according to any one of claims 1 to 8, characterized in that: The steps include: The raw materials are sequentially mixed, melted, extruded and granulated to obtain the flame retardant polycarbonate composition.

10. Use of the flame retardant polycarbonate composition according to any one of claims 1 to 8 in the preparation of electronic and electrical equipment.

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