Insulating flame-retardant polycarbonate composition and use thereof

Abstract

The application discloses an insulating flame-retardant polycarbonate composition and application thereof, and belongs to the technical field of high polymer materials. The polycarbonate composition is matched by specific types of voltage stabilizers and dispersants, can effectively improve the CTI electrical property of a product, makes CTI 300V greater than or equal to 50 drops, has excellent flame retardance, has sufficient room temperature and low-temperature toughness, and can be fully applied in the new energy field.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to an insulating and flame-retardant polycarbonate composition and its applications. Background Technology

[0002] As electronic devices used in the new energy field gradually become smaller and thinner, their supporting plastic parts (such as photovoltaic connectors or sheaths and protective partitions in new energy charging piles / charging guns) are increasingly required to have better electrical insulation and flame retardant and heat resistance. Polycarbonate is a material frequently used in the new energy field, but currently it can only meet the CTI 175V ≥ 50 drops requirement, and it will quickly fail (≤ 20 drops) when the voltage rises to 300V.

[0003] Although some products incorporate a large amount of electrical property modifiers into their components to improve their electrical properties, most of these components will affect the mechanical properties of the products, especially their low-temperature toughness, which greatly limits the scope of application of the products. Summary of the Invention

[0004] Based on the deficiencies of existing technologies, the purpose of this invention is to provide an insulating and flame-retardant polycarbonate composition. This product, through the combination of specific types of voltage stabilizers and dispersants, can not only effectively improve the CTI electrical properties of the product, making CTI 300V≥50 drops, and have excellent flame-retardant properties, but also has sufficient toughness at both room temperature and low temperature, making it fully applicable in the new energy field.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] An insulating and flame-retardant polycarbonate composition comprising the following components in parts by weight:

[0007] 55-95 parts polycarbonate, 1-20 parts toughening agent, 1-20 parts flame retardant, 0.01-10 parts voltage stabilizer, 0.01-1 part dispersant, and 0.1-5 parts anti-dripping agent;

[0008] The voltage stabilizer is at least one of anthraquinone and anthraquinone derivatives;

[0009] The dispersant is oxidized polyethylene wax with an acid value of 10-40 mg KOH / mol.

[0010] Preferably, the acid value of the dispersant is 15-35 mg KOH / mol.

[0011] Preferably, the insulating and flame-retardant polycarbonate composition comprises the following components in parts by weight:

[0012] The ingredients are: 60-90 parts polycarbonate, 1-20 parts toughening agent, 3-18 parts flame retardant, 0.1-8 parts voltage stabilizer, 0.01-1 parts dispersant, and 0.1-5 parts anti-dripping agent.

[0013] In traditional polycarbonate compositions, modifiers used to improve their electrical properties often suffer from incompatibility issues. This is mainly because these modifiers are generally small molecules that cannot effectively adhere to polycarbonate, which is amorphous and has a looser morphology than other plastics. Consequently, migration or even precipitation occurs, leading not only to appearance problems but also potentially affecting the mechanical properties of the product. On the other hand, due to the high carbonization structure of polycarbonate, although it has good self-extinguishing flame retardancy, the carbon circuit after carbonization under applied voltage is easily conductive, making electrical tracking failure more rapid than in other plastic systems. Therefore, in the polycarbonate composition of this invention, anthraquinone or its derivatives are used as voltage stabilizers. These substances, based on their unique phenyl structure, are well-compatible with polycarbonate. Combined with oxidized polyethylene waxes containing hydroxyl or carboxyl groups, the uniform dispersion of the components can be more effectively improved. Under the combined effect of these two, anthraquinone or its derivatives can fully exert their applied voltage stability, significantly enhance the trapping effect on charge carriers, and improve charge transport performance. This reduces localized charge concentration caused by structural defects in polycarbonate without reducing the product's flame retardancy. Furthermore, the use of this component ensures that the product possesses sufficient mechanical properties, especially room temperature and low temperature toughness. At -30°C, the product can achieve 250 J / m². 2 The above impact resistance.

[0014] Regarding the selection of dispersants, the inventors discovered that when the acid value of the dispersant is less than 10 mg KOH / mol, it contains insufficient carboxyl or hydroxyl groups, making it difficult to achieve a synergistic effect with the voltage stabilizer. If the acid value is higher than 40 mg KOH / mol, the compatibility between the dispersant and polycarbonate decreases, which not only leads to a decrease in the toughness of the product, but may also cause circuit conduction due to the increased antistatic properties of the component, resulting in a decrease in the CTI electrical properties of the product.

[0015] Preferably, the polycarbonate is in the range of 60 parts, 65 parts, 70 parts, 72 parts, 76 parts, 78 parts, 80 parts, 85 parts, and 90 parts by weight, or any two of these values; the toughening agent is in the range of 1 part, 5 parts, 12 parts, 15 parts, 18 parts, and 20 parts by weight, or any two of these values; the flame retardant is in the range of 3 parts, 5 parts, 12 parts, 15 parts, and 18 parts by weight, or any two of these values; and the voltage stabilizer is in the range of 0.1 parts, 0.5 parts by weight, or any two of these values. The weight parts of the dispersant are 0.01 parts, 0.05 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.8 parts, and 1 part, or any two of these values; the weight parts of the anti-drip agent are 0.1 parts, 0.5 parts, 0.6 parts, 1 part, 2 parts, 3 parts, 4 parts, and 5 parts, or any two of these values.

[0016] Preferably, the polycarbonate composition comprises the following components in parts by weight:

[0017] The composition includes 70-80 parts polycarbonate, 4-15 parts toughening agent, 5-15 parts flame retardant, 0.5-5 parts voltage stabilizer, 0.05-0.8 parts dispersant, and 0.3-1 parts anti-dripping agent. More preferably, the voltage stabilizer is 2-4 parts by weight, and the dispersant is 0.1-0.5 parts by weight.

[0018] More preferably, the polycarbonate composition contains ≥50 wt% polycarbonate.

[0019] Preferably, the anthraquinone derivative includes at least one of hydroxyanthraquinone, aminoanthraquinone, and dianthraquinone.

[0020] More preferably, the hydroxyanthraquinone is 2-hydroxyanthraquinone, and the aminoanthraquinone is 2,6-diaminoanthraquinone.

[0021] Similar to anthraquinone, the anthraquinone derivative has a special phenyl structure and electrical property-improving functional groups, which are specific compared to other electrical property modifiers. It can be used specifically to improve the CTI performance of polycarbonate products without reducing the flame retardancy and mechanical properties of the products.

[0022] Preferably, the acid value of the dispersant is a range of one or any two of the following: 10 mg KOH / mol, 12 mg KOH / mol, 14 mg KOH / mol, 16 mg KOH / mol, 18 mg KOH / mol, 20 mg KOH / mol, 22 mg KOH / mol, 25 mg KOH / mol, 28 mg KOH / mol, 30 mg KOH / mol, 32 mg KOH / mol, 35 mg KOH / mol, 38 mg KOH / mol, and 40 mg KOH / mol.

[0023] Preferably, the acid value of the dispersant is 20-30 mg KOH / mol.

[0024] When the acid value of the dispersant is maintained within the above range, it can not only effectively achieve high compatibility and high dispersibility of itself and its components in polycarbonate, but also effectively achieve synergistic effect with the voltage stabilizer to jointly improve the CTI electrical performance of the product.

[0025] More preferably, the acid value of the dispersant is obtained by testing according to ASTM D1386-15-2022.

[0026] More preferably, the number average molecular weight of the dispersant is 1,000 to 25,000, and even more preferably 2,500 to 5,000.

[0027] More preferably, the number average molecular weight of the dispersant is one or any two of the following: 2500, 2800, 3000, 3200, 3500, 3800, 4000, 4200, 4500, 4800, and 5000.

[0028] More preferably, the number average molecular weight of the dispersant is 3500 to 4500.

[0029] The number-average molecular weight of the dispersant was determined by the viscosity method according to SH / T 0398-2007.

[0030] More preferably, the dispersant has a melt flow rate of 6 to 150 g / 10 min at 300 °C and 1.2 kg load, according to ISO 1133-2012.

[0031] More preferably, the dispersant has a melt flow rate of 8 to 70 g / 10 min at 300 °C and 1.2 kg load, according to ISO 1133-2012.

[0032] More preferably, the dispersant has a melt flow rate of 10 g / 10 min, 15 g / 10 min, 20 g / 10 min, 30 g / 10 min, 40 g / 10 min, 50 g / 10 min, 60 g / 10 min, 65 g / 10 min, or 70 g / 10 min, according to ISO 1133-2012 at 300 °C and 1.2 kg load, or any two of these ranges.

[0033] More preferably, the dispersant has a melt flow rate of 10-15 g / 10 min at 300 °C and 1.2 kg load, according to ISO 1133-2012.

[0034] Preferably, the weight ratio of voltage stabilizer to dispersant in the polycarbonate composition is within the range of one or both of the following: 0.01:1, 1.6:1, 1.7:1, 3.75:1, 7.25:1, 10:1, 15.5:1, 16:1, 17:1, 32:1, 56:1, 60:1, and 100:1.

[0035] Preferably, in the polycarbonate composition, the weight ratio of voltage stabilizer to dispersant is (7-16):1. At this ratio, both effectively suppress localized charge accumulation in the polycarbonate while achieving optimal toughness and low-temperature toughness.

[0036] Preferably, the polycarbonate is bisphenol A type polycarbonate.

[0037] Preferably, the polycarbonate ISO1133-2012 has a melt flow rate of 3-26 g / 10 min at 300°C and 1.2 kg load.

[0038] Preferably, the polycarbonate has a number-average molecular weight of 22,000 to 30,000.

[0039] Preferably, the number average molecular weight of the polycarbonate is one or any two of the following: 22,000, 24,000, 25,000, 28,000, and 30,000.

[0040] The number-average molecular weight of the polycarbonate described in this invention can be directly detected by gel permeation chromatography.

[0041] More preferably, the polycarbonate has a terminal hydroxyl content of <100ppm and a BPA content of <20ppm.

[0042] Preferably, the toughening agent is at least one of SAN-grafted PB rubber, MMA-grafted silicone rubber, SAN-grafted silicone rubber, SEBS, and MBS.

[0043] More preferably, the toughening agent has a melt index of 0.1 to 5 g / 10 min at 300°C and 1.2 kg load according to ISO 1133-2012.

[0044] Preferably, the flame retardant is a halogen-free flame retardant.

[0045] More preferably, the halogen-free flame retardant is at least one of phosphorus-based flame retardants, sulfonate flame retardants, organosilicon flame retardants, and inorganic filler flame retardants.

[0046] More preferably, the halogen-free flame retardant is a phosphorus-based flame retardant, and the phosphorus content of the phosphorus-based flame retardant is ≥10wt%.

[0047] More preferably, the phosphorus-based flame retardant is at least one of DOPO (also known as DOP, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide), TPP (triphenyl phosphate), BDP (bisphenol A bis(diphenyl phosphate)), RDP (resorcinol (diphenyl phosphate)), phosphazene, and phosphate ester.

[0048] Preferably, the anti-dripping agent is at least one of polytetrafluoroethylene and styrene-acrylonitrile copolymer.

[0049] More preferably, the polycarbonate composition further includes at least one of the following: 0.01 to 1 part antioxidant, 0.01 to 1 part lubricant, 0.01 to 1 part reinforcing filler, and 0.01 to 1 part colorant.

[0050] Based on the needs of the actual product, those skilled in the art may appropriately introduce some components commonly used in polycarbonate products without affecting the product performance, such as antioxidants to improve the product's aging resistance, lubricants to improve the product's processing performance, reinforcing fillers to improve the product's rigidity, and colorants to give the product various colors, etc.

[0051] Another object of the present invention is to provide a method for preparing the insulating and flame-retardant polycarbonate composition, comprising the following steps:

[0052] After the components are mixed evenly, they are melt-extruded and granulated in a twin-screw extruder to obtain the insulating and flame-retardant polycarbonate composition.

[0053] The preparation method of the polycarbonate composition of the present invention has simple operation steps and can realize industrial-scale production.

[0054] Preferably, the temperature range of the twin-screw extruder is set to 220–280°C, the screw speed is 200–600 r / min, and the screw length-to-diameter ratio is 48:1.

[0055] Another object of the present invention is to provide the application of the aforementioned insulating and flame-retardant polycarbonate composition in the preparation of photovoltaic connectors or new energy charging power supplies.

[0056] The polycarbonate composition of this invention exhibits excellent CTI electrical properties and flame retardant properties, achieving a CTI 300V ≥ 50 drops, a flame retardant rating of V-0 at 1.5mm, and an impact strength of 500 J / m at room temperature. 2 Above, the impact strength at -30℃ reaches 250J / m. 2 In summary, its excellent overall performance makes it highly suitable for the manufacture of connectors or charging power supplies for charging piles and other live power sources that require the avoidance of high-voltage tracking failure and the presence of certain room temperature and low-temperature toughness.

[0057] The beneficial effects of this invention are that it provides an insulating and flame-retardant polycarbonate composition. This product, through the combination of specific types of voltage stabilizers and dispersants, can not only effectively improve the CTI electrical properties of the product, making CTI 300V≥50 drops, and have excellent flame-retardant properties, but also has sufficient toughness at room temperature and low temperature, which can be fully applied in the new energy field. Detailed Implementation

[0058] To better illustrate the purpose, technical solution, and advantages of this invention, the invention will be further described below with reference to specific embodiments and comparative examples. The purpose of this description is to provide a detailed understanding of the invention, not to limit its scope. All other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of this invention. Unless otherwise specified, the experimental reagents and instruments involved in the implementation of this invention are commonly used reagents and instruments.

[0059] Examples 1-17

[0060] An embodiment of an insulating and flame-retardant polycarbonate composition and its application according to the present invention is shown in Table 1.

[0061] The method for preparing the polycarbonate composition includes the following steps:

[0062] After all the components in the formulation are mixed uniformly in a high-speed mixer, they are fed into a twin-screw extruder through the main feed port for melt blending extrusion and granulation to obtain the polycarbonate composition.

[0063] During the melt blending extrusion of the components, the temperature zones of the twin-screw extruder are set as follows: Zone 1 200-220℃, Zone 2 210-230℃, Zone 3 215-235℃, Zone 4 215-235℃, Zone 5 215-235℃, Zone 6 220-245℃, Zone 7 220-245℃, Zone 8 220-245℃, Zone 9 220-240℃, Zone 10 220-240℃, Zone 11 210-230℃, and Zone 12 200-220℃. The screw speed is 400 rpm, and the screw length-to-diameter ratio is 48:1.

[0064] Comparative Examples 1-9

[0065] The only difference between each comparative example and the embodiment is the type and ratio of components, as shown in Table 2.

[0066] In the components described in each embodiment and comparative example,

[0067] The polycarbonate 1 is 1300-03NP, produced by LG Chem, with a melt flow rate of 3.5 g / 10 min at 300°C and 1.2 kg load, a number average molecular weight of 30,000, a terminal hydroxyl content of <100 ppm, and a BPA content of <20 ppm.

[0068] The polycarbonate 2 is 1300-10NP, produced by LG Chem, with a melt flow rate of 11.5 g / 10 min at 300°C and 1.2 kg load, a number average molecular weight of 26500, a terminal hydroxyl content of <100 ppm, and a BPA content of <20 ppm.

[0069] The polycarbonate 3 is 1300-22NP, produced by LG Chem, with a melt flow rate of 23.2 g / 10 min at 300°C and 1.2 kg load, a number average molecular weight of 22000, a terminal hydroxyl content of <100 ppm, and a BPA content of <20 ppm.

[0070] The toughening agent 1 is M521, MBS, manufactured by Kanekachi, Japan, and has a melt index of 1.3 g / 10 min at 300°C and 1.2 kg load according to ISO 1133.

[0071] The toughening agent 2 is S2501, MMA-grafted silicone rubber, manufactured by Mitsubishi Chemicals, Japan, with a melt index of 4.4 g / 10 min at 300°C and 1.2 kg load according to ISO 1133.

[0072] The flame retardant is a halogen-free phosphorus-based flame retardant phosphate ester with a phosphorus content of 9.1 wt%, produced by Daihachi, Japan as PX200 product.

[0073] The anti-dripping agent is commercially available polytetrafluoroethylene;

[0074] The voltage stabilizer 1 is a commercially available anthraquinone;

[0075] The voltage stabilizer 2 is a commercially available anthraquinone derivative, dianthraquinone;

[0076] The voltage stabilizer 3 is a commercially available hydroxyanthraquinone: 2-hydroxyanthraquinone.

[0077] The voltage stabilizer 4 is a commercially available aminoanthraquinone: 2,6-diaminoanthraquinone.

[0078] The voltage stabilizer 3 is commercially available phosphoric acid;

[0079] The voltage stabilizer 4 is hindered phenol 1076 produced by BASF (it should be noted that although this product is a common antioxidant, it also has a voltage stabilizing effect in PC alloys).

[0080] The dispersant 1 is AC325, manufactured by Honeywell, an oxidized polyethylene wax with an acid value of 25 mg KOH / mol, a number-average molecular weight of 4500, and a melt flow rate of 15 g / 10 min at 300 °C and 1.2 kg load.

[0081] The dispersant 2 is AC330, manufactured by Honeywell, an oxidized polyethylene wax with an acid value of 30 mg KOH / mol, a number-average molecular weight of 3600, and a melt flow rate of 12.5 g / 10 min at 300 °C and 1.2 kg load.

[0082] The dispersant 3 is 4202E, manufactured by Mitsui in Japan, which is an oxidized polyethylene wax with an acid value of 17 mg KOH / mol, a number-average molecular weight of 2600, and a melt flow rate of 67 g / 10 min at 300 °C and 1.2 kg load.

[0083] The dispersant 4 is 2203, manufactured by Mitsui in Japan, which is an oxidized polyethylene wax with an acid value of 35 mg KOH / mol, a number-average molecular weight of 2700, and a melt flow rate of 65 g / 10 min at 300 °C and 1.2 kg load.

[0084] The dispersant 5 is AC 307, manufactured by Honeywell, an oxidized polyethylene wax with an acid value of 7 mg KOH / mol, a number-average molecular weight of 85,000, and a melt flow rate of 1.2 g / 10 min at 300 °C and 1.2 kg load.

[0085] The dispersant 6 is AC 5120, manufactured by Honeywell, an oxidized polyethylene wax with an acid value of 120 mg KOH / mol, a number-average molecular weight of 575, and a melt flow rate of 287 g / 10 min at 300 °C and 1.2 kg load.

[0086] The dispersant 7 is NF308, manufactured by Mitsui in Japan. It is maleic anhydride-grafted polypropylene with an acid value of 30 mg KOH / mol and a melt flow rate of 100 g / 10 min at 190 °C and 2.16 kg load.

[0087] The dispersant 8 is PETS, and Lonza manufactures GLYCOBEP.

[0088] Unless otherwise specified, all components and raw materials used in the embodiments and comparative examples of this invention are commercially available, and the same type of components and raw materials are used in each parallel experiment.

[0089] Table 1

[0090]

[0091]

[0092] Table 2

[0093]

[0094] To verify the performance of the polycarbonate composition described in this invention, the products prepared in each embodiment and comparative example were subjected to the following performance tests, with the specific steps as follows:

[0095] (1) Room temperature IZOD notched impact strength test: According to ASTM D256 standard, each product was injection molded into impact specimens with a size of 3.2mm. The V-notch was used for testing, and the impact strength was 1.25J.

[0096] (2) -30℃ Notched Impact Strength Test: After placing the specimen in a -30℃ freezer oven for 4 hours, remove it and injection mold each product into an impact specimen with a size of 3.2mm according to ASTM D275 standard. The V-notch test is used to test the impact strength of 1.25J.

[0097] (3) 1.5mm flame retardancy rating test: The test and judgment are conducted in accordance with the UL94-2023 standard;

[0098] (4) CTI 300V test: The test and judgment are carried out in accordance with ASTM D3638 standard.

[0099] The test results are shown in Tables 3 and 4.

[0100] Table 3

[0101]

[0102] Table 4

[0103]

[0104] As shown in Tables 3 and 4, the polycarbonate composition of the present invention has a high impact strength at room temperature, reaching 600 J / m. 2 At -30℃ and above, the impact strength can reach 250J / m. 2 The products exhibit excellent toughness at both room and low temperatures. Furthermore, all products achieve a flame retardant V-0 rating at 1.5mm, with a CTI failure count of ≥50 drops at 300V, and a maximum of over 100 drops. In contrast, Comparative Examples 1 and 5, which did not incorporate voltage stabilizers and dispersants respectively, showed less ideal CTI and toughness performance. Comparisons with Examples 1, 10-11, 12-13, and Comparative Examples 2 and 6 indicate that the addition of these two components should not be excessive, otherwise it will weaken the product's performance in various aspects. Performance comparisons of Examples 1 and 14-17 show that when the total amount of both components is constant, and when their ratio is (7-16):1, the overall performance of the product is better. The product performance results from Examples 1, 6, 18-19, and Comparative Examples 3-4 show that conventional voltage stabilizers cannot truly achieve compatibility with the matrix resin, nor can they be well combined with dispersants, resulting in unsatisfactory CTI and toughness properties. Furthermore, a comparison between Example 1 and Comparative Examples 9 and 10 reveals that using commercially available, conventional processing dispersants, or using a different polyolefin as a dispersant, may not achieve the same performance improvement as the dispersant described in this invention. Moreover, the product performance results from Examples 1, 8-9, and Comparative Examples 7-8 show that even when using oxidized polyethylene wax with carboxyl and / or hydroxyl groups as a dispersant, the acid value of the product must be strictly controlled between 10 and 40 mKOH / mol (preferably 20-30 mKOH / mol). Otherwise, not only will the component compatibility of the product not be improved, but it may even negatively impact the CTI performance.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended 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. An insulating and flame-retardant polycarbonate composition, characterized in that, The components include the following parts by weight: 55-95 parts polycarbonate, 1-20 parts toughening agent, 1-20 parts flame retardant, 0.01-10 parts voltage stabilizer, 0.01-1 part dispersant, and 0.1-5 parts anti-dripping agent; The voltage stabilizer is at least one of anthraquinone and anthraquinone derivatives; the anthraquinone derivatives include at least one of hydroxyanthraquinone, aminoanthraquinone, and dianthraquinone. The dispersant is oxidized polyethylene wax with an acid value of 10~40 mgKOH / mol.

2. The polycarbonate composition according to claim 1, characterized in that, The acid value of the dispersant is 20~30 mgKOH / mol.

3. The polycarbonate composition according to claim 1, characterized in that, The dispersant has a number average molecular weight of 1000~25000 and a melt flow rate of 50~150 g / 10min at 300℃ and 1.2kg load according to ISO1133-2012.

4. The polycarbonate composition according to claim 1, characterized in that, In the polycarbonate composition, the weight ratio of voltage stabilizer to dispersant is (7~16):

1.

5. The polycarbonate composition according to claim 1, characterized in that, The polycarbonate, according to ISO 1133-2012, has a melt flow rate of 3~26 g / 10 min at 300℃ and 1.2 kg load, and a number average molecular weight of 22000~30000.

6. The polycarbonate composition according to claim 1, characterized in that, The toughening agent is at least one of SAN-grafted PB rubber, MMA-grafted silicone rubber, SAN-grafted silicone rubber, SEBS, and MBS.

7. The polycarbonate composition according to claim 1, characterized in that, The flame retardant is a halogen-free flame retardant; the anti-dripping agent is at least one of polytetrafluoroethylene and styrene-acrylonitrile copolymer.

8. The method for preparing the insulating and flame-retardant polycarbonate composition according to any one of claims 1 to 7, characterized in that, Includes the following steps: After the components are mixed evenly, they are melt-extruded and granulated in a twin-screw extruder to obtain the insulating and flame-retardant polycarbonate composition.

9. The application of the insulating and flame-retardant polycarbonate composition according to any one of claims 1 to 7 in the preparation of photovoltaic connectors or new energy charging power supplies.

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