Conductive pc alloy and its preparation method and application

Abstract

The application discloses a conductive PC alloy and a preparation method and application thereof, and belongs to the technical field of high polymer materials. In the case that a carbon nanotube conductive agent is introduced, specific ABS resin and PBT resin are selected and matched with a base PC resin, and acrylic silicone rubber is selected as a toughening agent. The product not only has high conductivity and meets the requirements of the electronic and electrical application field, but also has good low-temperature impact resistance and high glossiness, and has a wide application range.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a conductive PC alloy, its preparation method, and its application. Background Technology

[0002] Conductive PC alloy materials refer to PC alloys with the addition of components such as conductive masterbatches and conductive agents to improve overall conductivity without sacrificing basic performance characteristics. These materials are commonly used in the electronics and electrical appliance industries. Currently, due to considerations of production cost and overall performance, the conductive components in conductive PC alloy materials are mostly carbon-based materials, such as carbon nanotubes and carbon black. However, with the upgrading of usage requirements, electronic and electrical products often need to achieve sufficient impact resistance even in extreme environments such as sub-zero temperatures. Current conductive PC alloy products cannot achieve similar effects. Furthermore, due to the dispersion issues of the alloy system, these products generally have low gloss, making them difficult to apply to products requiring a glossy appearance. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention aims to provide a conductive PC alloy. This product, by introducing carbon nanotube conductive agents, combines specific types of ABS (acrylonitrile-butadiene-styrene terpolymer) resin and PBT (polybutylene terephthalate) resin with a PC matrix resin, and uses acrylic silicone rubber as a toughening agent. The product not only achieves high conductivity, meeting the requirements of electronic and electrical applications, but also possesses excellent low-temperature impact resistance and high gloss, making it suitable for a wide range of applications.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A conductive PC alloy comprising the following components in parts by weight:

[0006] 60-85 parts PC resin, 5-20 parts ABS resin, 2-10 parts PBT resin, 5-20 parts toughening agent, and 0.5-3 parts carbon nanotubes;

[0007] The intrinsic viscosity of the PBT resin at 25°C is ≤1.05 dL / g;

[0008] The butadiene mass fraction of the ABS resin is 16-25%;

[0009] The toughening agent is an acrylic silicone toughening agent.

[0010] In conductive PC alloy products, carbon-based materials, especially carbon nanotubes, which are inexpensive and intrinsically highly conductive, are often used as conductive agents. To ensure the dispersibility of these inorganic powders and enable them to exert their normal conductive effect, the matrix resin in the product needs to maintain a certain degree of fluidity when combined with the inorganic powder. However, these products cannot simultaneously achieve high impact resistance, especially at low temperatures, where they fail to meet normal toughness requirements. On the other hand, due to the use of inorganic conductive agents, existing conductive PC alloy products generally have low gloss, resulting in substandard appearance when used in electronic and electrical packaging materials, thus limiting their application range. Therefore, in the technical solution of this invention, ABS resin and PBT resin are introduced into the PC resin-carbon nanotube alloy product system, along with a specific acrylic silicone toughening agent. The resulting alloy product not only possesses good low-temperature impact resistance and gloss, but also maintains high conductivity due to the high dispersibility of carbon nanotubes within the product system, resulting in excellent overall performance.

[0011] However, in the product described in this invention, the selection of ABS resin and PBT resin is not arbitrary. The inventors have discovered that the butadiene content in ABS resin is related to the low-temperature toughness of the product and the dispersibility of carbon nanotubes. If the selection is inappropriate, it will not only fail to ensure that the toughening agent makes the product have sufficient impact resistance in low-temperature environments, but may also fail to achieve the expected gloss due to the low dispersion and low compatibility of carbon nanotubes. On the other hand, as a wetting agent for carbon nanotubes in the resin system, the viscosity of PBT resin when in contact with carbon nanotubes is related to the wetting effect of carbon nanotubes and the dispersion effect of PBT resin in the overall resin system. If the viscosity is too high, the carbon nanotubes in the product cannot be well dispersed, the product has poor electrical conductivity, and the toughness effect at low temperatures cannot be achieved.

[0012] Preferably, in the conductive PC alloy, the total mass content of PC resin, ABS resin and PBT resin is ≥70wt%.

[0013] Preferably, the conductive PC alloy comprises the following components in parts by weight:

[0014] 70-80 parts PC resin, 10-15 parts ABS resin, 4-6 parts PBT resin, 6-13 parts toughening agent, and 1-2 parts carbon nanotubes.

[0015] Preferably, the PC resin has a melt index of 8 to 30 g / 10 min at 300°C and 1.2 kg, according to ISO 1133-2011.

[0016] More preferably, the melt index of the PC resin at 300°C and 1.2 kg is one or any two of the following: 8 g / 10 min, 10 g / 10 min, 12 g / 10 min, 15 g / 10 min, 18 g / 10 min, 19 g / 10 min, 20 g / 10 min, 22 g / 10 min, 25 g / 10 min, 28 g / 10 min, and 30 g / 10 min.

[0017] More preferably, the melt index of the PC resin at 300°C and 1.2 kg is 10-20 g / 10 min.

[0018] In the conductive PC alloy of the present invention, changes in the melt index of PC resin will lead to changes in the overall resin compatibility, overall strength and carbon nanotube dispersion. Preferably, when the melt index of PC resin is within the above range, the product can achieve higher surface gloss and low-temperature impact resistance while meeting the requirement of lower resistance.

[0019] Preferably, the intrinsic viscosity of the PBT resin at 25°C is 0.85–1.05 dL / g.

[0020] More preferably, the intrinsic viscosity of the PBT resin at 25°C is one or any two of the following: 0.85 dL / g, 0.88 dL / g, 0.90 dL / g, 0.92 dL / g, 0.95 dL / g, 1.0 dL / g, and 1.05 dL / g.

[0021] More preferably, the intrinsic viscosity of the PBT resin at 25°C is 0.9 to 1.05 dL / g.

[0022] As mentioned above, the viscosity of PBT resin is related to the wetting and dispersibility of carbon nanotubes in the product. When it is preferably within the above range, the PBT can fully react with the polar groups on the surface of carbon nanotubes, resulting in better compatibility between organic resin and inorganic components in the product and exhibiting better overall performance.

[0023] Preferably, the average particle size of the ABS resin is 0.2 to 1.2 mm, and the mass fraction of acrylonitrile in the ABS resin is 15 to 50%.

[0024] Preferably, the mass fraction of butadiene in the ABS resin is one or any two of the following: 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, and 25%.

[0025] More preferably, the mass fraction of butadiene in the ABS resin is 18-22%.

[0026] When the butadiene content of the ABS resin is selected within the above-mentioned preferred range, the product can achieve a better balance between gloss and low-temperature impact resistance.

[0027] Preferably, the ABS resin has a melt flow index of ≥8 g / 10 min at 230°C and 10 kg, according to ISO 1133-2011.

[0028] More preferably, the melt flow index of the ABS resin at 230°C and 10 kg is 10-20 g / 10 min.

[0029] More preferably, the melt index of the ABS resin at 230°C and 10 kg is one or any two of the following: 10 g / 10 min, 12 g / 10 min, 14 g / 10 min, 16 g / 10 min, 18 g / 10 min, and 20 g / 10 min.

[0030] Preferably, in the conductive PC alloy, the mass ratio of ABS resin to toughening agent is (2:1) to (5:4).

[0031] In the product described in this invention, both ABS resin and toughening agent affect the toughness and component uniformity of the product. After optimization, the inventors found that when the mass ratio of the two is selected within the above range, the product can achieve better component uniformity and low-temperature mechanical properties.

[0032] It should be noted that the product of the present invention also includes 0.01 to 3 parts of processing aids. More preferably, the processing aids include lubricants, antioxidants, etc. Those skilled in the art can add them according to actual needs, as long as it does not affect the expected technical effect of the product of the present invention.

[0033] Preferably, the conductive PC alloy further comprises 0.5 to 1 part antioxidant and 1 to 2 parts lubricant.

[0034] More preferably, the antioxidant includes at least one of hindered phenolic antioxidants, phosphite antioxidants, and hindered amine antioxidants; the lubricant includes at least one of stearic acid lubricants, amide lubricants, and alkyl acid lubricants.

[0035] Preferably, the specific surface area of ​​the carbon nanotubes is 240–300 m². 2 / g.

[0036] The specific surface area of ​​the carbon nanotubes was confirmed by nitrogen adsorption-desorption method, referring to GBT-10722-2014.

[0037] Preferably, the acrylic silicone toughening agent has a core-shell structure, wherein the core layer comprises a composite of silicone and polyacrylate, and the shell layer comprises polymethyl methacrylate.

[0038] Preferably, the acrylic silicone toughening agent has a melt flow rate of 8–15 g / 10 min at 300°C and 1.2 kg load according to ISO-1133-2011, and a density of 1–1.5 g / cm³ according to ISO-1183-2019. 3 .

[0039] Preferably, the mass ratio of the core layer to the shell layer in the acrylic silicone toughening agent is (0.5:9.5) to (1.5:8.5).

[0040] Another object of the present invention is to provide a method for preparing the conductive PC alloy, comprising the following steps:

[0041] After the components are mixed evenly, they are melt-extruded and granulated in a screw extruder to obtain the conductive PC alloy.

[0042] The preparation method of the conductive PC alloy described in this invention has simple operation steps and can achieve industrial-scale production.

[0043] Preferably, the temperature range of the screw extruder is set to 200–320°C, the screw speed is 400–600 r / min, and the screw length-to-diameter ratio is (45–50):1.

[0044] Another object of the present invention is to provide the application of the conductive PC alloy in the preparation of electronic and electrical packaging materials.

[0045] Preferably, the packaging materials for electronic appliances include turnover boxes and electronic trays.

[0046] Another object of the present invention is to provide an electronic and electrical packaging material, including the conductive PC alloy described in the present invention.

[0047] The conductive PC alloy described in this invention possesses ideal comprehensive properties, maintaining sufficient impact resistance at low temperatures and achieving at least 20 KJ / m at -40°C. 2 It has high impact strength, high gloss, and good conductivity, thus meeting both the appearance and practicality requirements of electronic and electrical packaging materials.

[0048] The beneficial effects of this invention are that it provides a conductive PC alloy. This product, by introducing carbon nanotube conductive agents, selects specific types of ABS resin and PBT resin to match with the base PC resin, and selects acrylic silicone rubber as a toughening agent. The product not only achieves high conductivity, meeting the requirements of electronic and electrical applications, but also has good low-temperature impact resistance and high gloss, making it suitable for a wide range of applications. Detailed Implementation

[0049] 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.

[0050] Examples 1-15

[0051] Examples of the conductive PC alloy, its preparation method, and its application according to the present invention are shown in Table 1.

[0052] The preparation method of the product includes the following steps:

[0053] The components are mixed evenly, and then placed in a screw extruder for melt extrusion granulation to obtain the conductive PC alloy.

[0054] The temperature zones of the screw extruder are set as follows: Zone 1: 200℃, Zone 2: 240℃, Zone 3: 240℃, Zone 4: 240℃, Zone 5: 240℃, Zone 6: 240℃, Zone 7: 240℃, Zone 8: 240℃, Zone 9: 240℃, Zone 10: 300℃. The screw speed is 500 r / min, and the length-to-diameter ratio is 48:1.

[0055] Comparative Examples 1-6

[0056] The only difference between each comparative example and the embodiment is the type and ratio of components, as shown in Table 2.

[0057] In the components described in each embodiment and comparative example,

[0058] PC resin 1 is PC2220 produced by Wanhua Chemical, with a melt index of 19 g / 10 min at 300℃ and 1.2 kg.

[0059] PC resin 2 is S-2000F manufactured by Mitsubishi Corporation of Japan, with a melt index of 10g / 10min at 300℃ and 1.2kg.

[0060] PC resin 3 is L-1250 manufactured by Teijin, Japan, with a melt index of 8 g / 10 min at 300℃ and 1.2 kg.

[0061] PC resin 4 is HPF1 produced by SBIC Corporation of the United States, with a melt index of 25 g / 10 min at 300°C and 1.2 kg.

[0062] ABS resins 1-5 were prepared directly in the laboratory using a blending method. The materials, polybutadiene-grafted SAN resin and SAN resin, were mixed evenly in a certain proportion and extruded using a twin-screw extruder to prepare ABS resin granules.

[0063] The polybutadiene-grafted SAN is EB-168 produced by Shandong Yigong Chemical Co., Ltd., with a butadiene mass fraction of 60%; the SAN resin is 310TR produced by Kumho Chemical Co., Ltd. in South Korea.

[0064] ABS Resin 1: Material ratio of polybutadiene grafted SAN: SAN = 33:66, the mass fraction of butadiene in the resulting product is 20%, and the melt index is 15g / 10min;

[0065] ABS resin 2: Material ratio of polybutadiene grafted SAN: SAN = 27:73, the mass fraction of butadiene in the resulting product is 16%, and the melt index is 19 g / 10 min;

[0066] ABS resin 3: Material ratio of polybutadiene grafted SAN: SAN = 42:58, the mass fraction of butadiene in the resulting product is 25%, and the melt index is 10g / 10min;

[0067] ABS resin 4: Material ratio of polybutadiene grafted SAN: SAN = 16.8: 83.2, the mass fraction of butadiene in the resulting product is 10%, and the melt index is 25 g / 10 min;

[0068] ABS resin 5: Material ratio of polybutadiene grafted SAN: SAN = 1:1, the resulting product has a butadiene mass fraction of 30% and a melt index of 7 g / 10 min;

[0069] PBT resin 1 is PBT GX122J produced by Yizheng Petrochemical, with an intrinsic viscosity of 1.05 dL / g at 25℃;

[0070] PBT resin 2 is PBT GX121 produced by Yizheng Petrochemical, with an intrinsic viscosity of 0.95 dL / g at 25℃;

[0071] PBT resin 3 is GX112 produced by Yizheng Petrochemical, with an intrinsic viscosity of 0.85 dL / g at 25℃;

[0072] PBT resin 4 is PBT GL236 produced by Yizheng Petrochemical, with an intrinsic viscosity of 1.28 dL / g at 25℃;

[0073] The carbon nanotubes were manufactured by Shandong Dazhan as GC-210, with a specific surface area of ​​260 g / m². 2 ;

[0074] Toughening agent 1 is S-2001 manufactured by Mitsubishi Corporation of Japan. It is a core-shell structure acrylic silicone toughening agent with a core layer consisting of a composite of silicone and polyacrylate, and a shell layer consisting of polymethyl methacrylate.

[0075] Toughening agent 2 is M-521 produced by Kaneka Corporation of Japan. It is a core-shell structured methyl methacrylate-butadiene-styrene toughening agent. The core layer consists of a polymer of butadiene and styrene, and the shell layer is polymethyl methacrylate.

[0076] Toughening agent 3 is S-2100 manufactured by Mitsubishi Corporation of Japan. It is a core-shell structured acrylic silicone toughening agent. The core layer consists of a composite of silicone and polyacrylate, and the shell layer is polymethyl methacrylate.

[0077] Toughening agent 4 is POE ENGAGE 8137 manufactured by Dow Chemical Company in the United States, which is an ethylene-octene copolymer;

[0078] Unless otherwise specified, the antioxidants, lubricants and other processing aids and anti-dripping agents used in the embodiments and comparative examples of this invention are all commercially available raw materials, and the raw materials used in each parallel experiment are all the same.

[0079] Table 1

[0080]

[0081] Table 2

[0082] Components by weight Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 PC resin 1 75 75 75 75 75 75 ABS resin 1 10 10 10 10 ABS resin 4 10 ABS resin 5 10 PBT resin 1 5 5 20 5 5 PBT resin 4 5 carbon nanotubes 1.5 1.5 1.5 1.5 1.5 1.5 Toughening agent 1 8 8 8 8 Toughening agent 2 8 Toughening agent 4 8

[0083] Example 1

[0084] To verify the performance of the product described in this invention, the following performance tests were conducted on the products of each embodiment and comparative example, with the specific steps as follows:

[0085] (1) Surface resistance test: Each product was injection molded (mold temperature 80℃, injection temperature 260℃) into a test square plate of 100×100×3mm. Then, an RT1000 resistance meter was used to directly test the resistance of 5 samples and the average value was taken.

[0086] (2) Gloss test: Each product was injection molded (mold temperature 80℃, injection temperature 260℃) into a test square plate of 100×100×3mm, and then tested at 60° using a YG60S gloss meter with the angle method.

[0087] (3) Low-temperature notched impact strength test: Each product was injection molded into a test impact specimen with dimensions of (80±2)×(10.0±0.2)×(4.0±0.2)mm and a notch width of (8.0±0.2)mm. The specimen was first placed in a freezer at -40℃ for 8 hours. Then, it was taken out and the notched impact strength test was performed according to GB / T1843-2008. The notch was type A and the impact energy was 5.5J. The test was completed within 20 seconds after the specimen was taken out.

[0088] The test results are shown in Tables 3 and 4.

[0089] Table 3

[0090]

[0091] Table 4

[0092] Components by weight Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Surface resistance <![CDATA[2.71*10 6 ]]> <![CDATA[1.67*10 5 ]]> <![CDATA[9.78*10 8 ]]> <![CDATA[3.25*10 8 ]]> <![CDATA[4.89*10 9 ]]> <![CDATA[6.33*10 7 ]]> Glossiness (°) 88 60 29 52 69 67 <![CDATA[Low temperature Charpy impact strength (KJ / m 2 )]]> 5 33 22 8 5 4

[0093] As can be seen from Tables 3 and 4, due to the specific PC / ABS / PBT resin system and the selection of toughening agents, the PC alloy product containing conductive carbon nanotubes described in this invention not only exhibits good electrical conductivity, but also has a surface resistivity that, as tested, can reach E6 (i.e., below 1*10). 7 In addition, regarding its use and appearance, the product exhibits good low-temperature impact resistance, with an impact strength of at least 20 KJ / m at -40°C. 2 It also has a high gloss level, reaching 70° or higher.

[0094] In the products of each embodiment, as can be seen from Examples 1 and 4-6, the melt index of PC resin has a certain impact on the performance of the product. When it is preferably in the range of 10-20 g / 10 min, the resulting product can maintain a higher level of gloss and low-temperature impact resistance without a significant increase in surface resistance, and the overall performance is better.

[0095] As can be seen from Examples 1, 7-8, and Comparative Examples 1-2, the butadiene content of the ABS resin has a significant impact on the performance of the product. When the butadiene content is low, the gloss of the resulting product is high, but the low-temperature impact resistance is extremely low, making it unusable in low-temperature environments. As the butadiene content increases, the low-temperature impact resistance of the product can be improved while maintaining a high gloss level. However, if the butadiene content of the ABS resin is too high, as shown in Comparative Example 2, the gloss of the product will be significantly reduced.

[0096] As can be seen from Examples 1, 9-10, and Comparative Example 3, the viscosity of the PBT resin in the product directly affects the dispersibility of carbon nanotubes, as well as the compatibility and flowability between the resins. When the intrinsic viscosity of the PBT resin at 25°C is maintained within 1.05 dL / g, the product achieves a good overall performance. Especially when the intrinsic viscosity is maintained at 0.9 dL / g or higher, the product obviously has lower surface resistivity and achieves a higher level of low-temperature impact resistance. However, if the specific properties of the PBT resin exceed the aforementioned range, the product performance will decrease significantly. Not only will the surface resistivity increase due to the decreased dispersibility of carbon nanotubes, and the gloss decrease, but the low-temperature impact resistance will also be significantly weakened. Furthermore, the amount of PBT resin added should not be excessive. As shown in Comparative Example 4, if the ratio of resins is inappropriate, resulting in an excessively high proportion of PBT resin, all the product's properties will fail to meet the standards.

[0097] On the other hand, the selection of toughening agent in the conductive PC alloy of this invention is also crucial. Besides affecting the low-temperature impact resistance of the product, this component also significantly influences the dispersion of carbon nanotubes in the resin. Comparative Examples 5 and 6 used toughening agents not specified in this invention, resulting in high surface resistivity, low gloss, and possibly due to poor compatibility between these two toughening agents in the product system, their low-temperature notched impact strength was less than 10 KJ / m. 2 .

[0098] In the product system, the inventors' experiments found that the ratio of toughening agent to ABS resin also affects the performance of the product to a certain extent. When the ratio of the two is preferably between (2:1) and (5:4), the surface resistance of the product is lower, and the gloss and low-temperature impact resistance are better.

[0099] 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. A conductive PC alloy, characterized in that, The components include the following parts by weight: 60-85 parts PC resin, 5-20 parts ABS resin, 2-10 parts PBT resin, 5-20 parts toughening agent, and 0.5-3 parts carbon nanotubes; The intrinsic viscosity of the PBT resin at 25°C is 0.85~1.05 dL / g; The butadiene mass fraction of the ABS resin is 16-25%; The toughening agent is an acrylic silicone toughening agent; the acrylic silicone toughening agent has a core-shell structure.

2. The conductive PC alloy as described in claim 1, characterized in that, The PC resin has a melt index of 8~30g / 10min at 300℃ and 1.2kg according to ISO1133-2011.

3. The conductive PC alloy as described in claim 1, characterized in that, The ABS resin, according to ISO 1133-2011, has a melt index of ≥8 g / 10 min at 230°C and 10 kg.

4. The conductive PC alloy as described in claim 1, characterized in that, In the conductive PC alloy, the mass ratio of ABS resin to toughening agent is (2:1) to (5:4).

5. The conductive PC alloy as described in claim 1, characterized in that, The core layer of the acrylic silicone toughening agent comprises a composite of silicone and polyacrylate, and the shell layer comprises polymethyl methacrylate.

6. The method for preparing the conductive PC alloy according to any one of claims 1 to 5, characterized in that, Includes the following steps: After the components are mixed evenly, they are melt-extruded and granulated in a screw extruder to obtain the conductive PC alloy.

7. The application of the conductive PC alloy as described in any one of claims 1 to 5 in the preparation of electronic and electrical packaging materials.

8. The application as described in claim 7, characterized in that, The packaging materials for electronic appliances include turnover boxes and pallets.

9. An electronic and electrical appliance packaging material, characterized in that, Includes the conductive PC alloy according to any one of claims 1 to 5.

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