A polycarbonate composition, its preparation and use

Abstract

This invention belongs to the field of plastic materials, specifically disclosing a polycarbonate composition, its preparation method, and its applications. In the polycarbonate composition of this invention, the rigidity of glass fiber reinforcement is utilized, and with the combination of silicon copolymer polycarbonate, EMA, and organosilicon toughening agent, the polycarbonate composition simultaneously possesses high rigidity, high toughness, and high bending resistance, making it more suitable for applications in mobile phones and robotics.

Description

Technical Field

[0001] This invention belongs to the field of plastics, specifically relating to a polycarbonate composition, its preparation method, and its application. Background Technology

[0002] Polycarbonate (PC) is a thermoplastic engineering plastic with excellent comprehensive performance. It has high light transmittance, high impact resistance, and excellent mechanical and thermal properties. It can be made into various parts through injection molding, extrusion, compression molding and other methods. It is widely used in automotive parts, aerospace, consumer electronics, home appliances, building materials, optical lenses and special protective equipment, medical devices and other fields.

[0003] Developing and applying glass fiber reinforced polycarbonate (GFRP) to mobile phone frames or robots is a highly forward-looking and strategically significant direction in the field of consumer electronics materials, representing a delicate balance between pursuing ultimate performance and cost control. This is because, on the one hand, the glass fibers in GFRP significantly improve the rigidity of PC, giving it a high modulus sufficient to meet the structural rigidity requirements of mobile phones or robots, preventing deformation during use and providing effective protection for internal displays and motherboards, greatly improving the material's fatigue life. On the other hand, its insulating properties enable integrated wireless charging and signal freedom, acting as a natural antenna window allowing signals to pass freely. This allows for truly seamless, integrated designs in mobile phones or robots, resulting in a simpler appearance and solving the signal shielding and wireless charging limitations of traditional metal frames, providing significant convenience for the more complex antenna designs of the 5G / 6G era. Furthermore, GFRP is lightweight, significantly reducing the overall weight of mobile phones or robots and improving grip comfort.

[0004] However, glass fiber has poor compatibility with the PC matrix. In systems with low glass fiber content, the reinforcing effect of glass fiber on PC is not significant; significantly increasing the glass fiber content leads to a substantial sacrifice in the material's toughness and bending resistance. Existing glass fiber reinforced polycarbonate materials cannot simultaneously achieve high rigidity, toughness, and bending resistance, thus limiting their application in scenarios where these three properties need to be balanced. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing glass fiber reinforced polycarbonate materials that cannot simultaneously achieve high rigidity, toughness, and bending resistance. This invention will provide a polycarbonate composition, its preparation method, and its application.

[0006] To achieve the above objectives, the following technical solutions are specifically included: In one aspect, the present invention provides a polycarbonate composition comprising the following components in parts by weight: PC resin 58-96, silicone copolymer polycarbonate 9-41 parts, ethylene-methyl acrylate copolymer (EMA) 0.9-6 parts, silicone toughening agent 0.5-4.5 parts, glass fiber 9-31 parts.

[0007] In the polycarbonate composition of the present invention, glass fiber can significantly improve the modulus and rigidity of the composition. The three components, silicon copolymer polycarbonate, EMA and organosilicon toughening agent, work together to significantly improve the toughness and bending resistance of the composition while maintaining high rigidity. This results in a final polycarbonate composition that simultaneously possesses high rigidity, high toughness and high bending resistance, making it more suitable for applications in mobile phones and robotics.

[0008] Preferably, the polycarbonate composition comprises the following components in parts by weight: 60-95 parts PC resin, 10-40 parts silicone copolymer polycarbonate, 1-5 parts ethylene methyl acrylate copolymer, 1-4 parts silicone toughening agent, and 10-30 parts glass fiber.

[0009] Preferably, the polycarbonate composition contains at least 50% polycarbonate (PC) by mass, and more preferably at least 60%.

[0010] Preferably, the PC resin includes bisphenol A type PC resin.

[0011] Preferably, the melt flow rate of the PC resin is 1-30 g / 10 min, wherein the melt flow rate is tested according to ISO 1133-1 2011 standard, and the test conditions are 300℃ and 1.2 kg. More specifically, the melt flow rate of the PC resin can be 1 g / 10 min, 2 g / 10 min, 3 g / 10 min, 4 g / 10 min, 5 g / 10 min, 6 g / 10 min, 7 g / 10 min, 8 g / 10 min, 9 g / 10 min, 10 g / 10 min, 11 g / 10 min, 12 g / 10 min, 13 g / 10 min, 14 g / 10 min, 15 g / 10 min, 16 g / 10 min, etc. The specific values ​​within the ranges are 0 min, 17 g / 10 min, 18 g / 10 min, 19 g / 10 min, 20 g / 10 min, 21 g / 10 min, 22 g / 10 min, 23 g / 10 min, 24 g / 10 min, 25 g / 10 min, 26 g / 10 min, 27 g / 10 min, 28 g / 10 min, 29 g / 10 min, 30 g / 10 min, etc., as well as the specific values ​​between the above values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list the specific values ​​included in the ranges.

[0012] Preferably, the silicon content in the silicon-copolymer polycarbonate is 3%-22% by mass, wherein the silicon content is measured by ICP-MS. More specifically, it can be 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, etc., as well as specific values ​​between the above ranges. For space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the ranges. Inductively coupled plasma mass spectrometry (ICP-MS) is used to test the silicon content in the silicon-copolymer polycarbonate.

[0013] Preferably, the mass ratio of the PC resin to the silicon copolymer polycarbonate is (1-8):1, which can specifically be 1:1, 1.25:1, 1.56:1, 1.95:1, 2.44:1, 3.05:1, 3.81:1, 4.77:1, 5.96:1, 7.45:1, 8:1, etc., as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list the specific values ​​included in the range.

[0014] Preferably, the methyl acrylate segment in the ethylene-methyl acrylate copolymer has a mass percentage content of 18%-35%, specifically 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, etc., and specific values ​​between the above ranges. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the range. The methyl acrylate segment is measured using proton nuclear magnetic resonance (NMR) spectroscopy, utilizing the differences in chemical shifts of hydrogen atoms under different chemical environments. In EMA, the hydrogen atom of the -OCH3 group (methoxy group) on the methyl acrylate unit appears at ~3.6 ppm in the NMR spectrum, and the -CH2- hydrogen atom on the ethylene unit appears in the ~1.2-1.4 ppm region. Quantitative analysis of the methyl acrylate peaks yields its content.

[0015] Preferably, the mass ratio of the ethylene-methyl acrylate copolymer to the organosilicon toughening agent is (1-3.5):1, which can specifically be 1.0:1, 1.2:1, 1.4:1, 1.6:1, 1.8:1, 2.0:1, 2.2:1, 2.4:1, 2.6:1, 2.8:1, 3.0:1, 3.2:1, 3.4:1, 3.5:1, etc., as well as specific values ​​between the above-mentioned values. Due to space limitations and for the sake of brevity, this invention will not exhaustively list the specific values ​​included in the range.

[0016] Preferably, the organosilicon toughening agent has a core-shell structure, wherein the core comprises a siloxane and the shell comprises an acrylate.

[0017] More preferably, the silicon element content in the organosilicon toughening agent is 6%-30% by mass, specifically 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, etc., as well as specific values ​​between the above ranges. For space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the ranges. The mass percentage content of silicon and its siloxanes is tested using ICP-MS.

[0018] Preferably, the average diameter of the glass fiber is 5-20 μm, more preferably 10-13 μm, and more specifically, it can be 5 μm, 7 μm, 9 μm, 11 μm, 13 μm, 15 μm, 17 μm, 19 μm, 20 μm, etc., as well as specific values ​​between the above values. For space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the range. The average length of the glass fiber is 1-5 mm, specifically 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, etc., as well as specific values ​​between the above values. For space limitations and for the sake of brevity, this invention will not exhaustively list all the specific values ​​included in the range. The average diameter and length of the glass fiber can be tested using a scanning electron microscope.

[0019] Preferably, the polycarbonate composition further includes processing aids comprising the following components in parts by weight: 0.1-1.5 parts antioxidant and 0.1-1.5 parts lubricant.

[0020] More preferably, the antioxidant includes at least one of hindered phenolic antioxidants, phosphite antioxidants, and organosulfur antioxidants. More specifically, it may include at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (antioxidant 1010), pentaerythritol tetrakis(3-lauryl thiopropionate) (antioxidant 412S), and tris[2,4-di-tert-butylphenyl] phosphite (antioxidant 168).

[0021] More preferably, the lubricant comprises at least one of aliphatic carboxylic acid esters, erucamide, ethylene bis-stearamide, montan esters, polyethylene wax, and oxidized polyethylene wax.

[0022] On the other hand, the present invention provides a method for preparing the polycarbonate composition, comprising the following steps: mixing, melting, extruding and granulating the raw materials in sequence to obtain the polycarbonate composition.

[0023] Preferably, the melting temperature is 260~280℃.

[0024] In addition, the present invention also provides an application of the polycarbonate composition described above in the preparation of mobile phones and robots, specifically including components such as mobile phone frames, mobile phone protective cases, and robot shells.

[0025] Compared with the prior art, the present invention has the following beneficial effects: In the polycarbonate composition of the present invention, the rigidity of the glass fiber reinforced material is utilized, and with the combination of silicon copolymer polycarbonate, EMA and organosilicon toughening agent, the polycarbonate composition simultaneously has high rigidity, high toughness and high bending resistance, making it more suitable for application in the fields of mobile phones and robots. Detailed Implementation

[0026] To better illustrate the purpose, technical solution, and advantages of this invention, specific embodiments will be used to further explain the invention below. Unless otherwise specified, the experimental methods used in the embodiments and / or comparative examples are conventional methods; the materials and reagents used, unless otherwise specified, are commercially available. Unless otherwise specified, the raw materials used in each embodiment and comparative example of this invention are the same in each parallel experiment.

[0027] Raw material information involved in the following examples and comparative examples: PC-1: TRIREX 3030PJ, melt flow rate of 3 g / 10 min, Samyang, South Korea; PC-2: TRIREX 3025PJ, melt flow rate of 10g / 10min, Samyang, South Korea; PC-3: H-2000, melt flow rate of 22g / 10min, Mitsubishi, Japan; Silicon copolymer polycarbonate resin-1 (Si-PC-1): TS-2020, silicon content is 3wt%, Teijin. Silicon-copolymer polycarbonate resin 2 (Si-PC-2): 8000-05, silicon content 8wt%, LG Korea; Silicon-copolymer polycarbonate resin 3 (Si-PC-3): PC S2060, silicon content 20wt%, Wanhua Chemical; EMA-1: Lotryl® 18MA005, methyl acrylate (MA) content 18wt%, Arkema. EMA-2: Lotryl® 28MA07, MA content 28wt%, Arkema. EMA-3: Lotryl® 35MA08, MA content 35wt%, Arkema; Organosilicon toughening agent-1: LP2082, Si content 6wt%, entropy energy; Organosilicon toughening agent-2: S-2001, Si content 8wt%, Mitsubishi Rayon; Organosilicon toughening agent-3: LP2088, Si content 30wt%, entropy energy; Non-silicone toughening agents: PA-20, MBS-based toughening agents, Kenka; Fiberglass: HMG436S-10-4.0, diameter 10μm, length 4mm, Taishan Fiberglass Co., Ltd. Processing aid 1: Antioxidant 1010, Rianon; Processing aid 2: Luwax® OA 521, oxidized polyethylene wax, BASF.

[0028] Examples 1-18 and Comparative Examples 1-5 A method for preparing a polycarbonate composition includes the following steps: (1) According to the amount of raw material components in Tables 1 and 2, mix all components except glass fiber in a mixer to obtain a premix; (2) The premixed material is fed into a twin-screw extruder through the main feed port, and glass fiber is fed to the side. The material is melted, extruded and granulated in the twin-screw extruder to obtain a polycarbonate composition, wherein the screw length-to-diameter ratio is 45:1, the screw barrel temperature is 260~280℃ and the screw speed is 550rpm.

[0029] The test methods for various properties of the polycarbonate compositions in the embodiments and comparative examples of the present invention are as follows: (1) Bending properties: The bending modulus (MPa) of the material was tested according to the method in ISO 178-2019. (2) Impact performance: The cantilever beam notched impact strength of the material was tested according to the method in ISO 180-2023, with an A-notch, and the ambient temperature was 23℃. (3) Bending resistance: A rectangular strip with a length of 125mm, a width of 13mm and a thickness of 0.8mm is bent alternately 80° from the middle and back. The number of bending resistances before breakage is recorded. A number of bending resistances before breakage ≥ 10 times is considered qualified. The test results are shown in Table 1-2.

[0030] Table 1 Polycarbonate Compositions Table 2 Polycarbonate Compositions As can be seen from the above embodiments, the flexural modulus of the carbonate composition of the present invention reaches 5000-7500 MPa and the impact strength reaches 13-17 kJ / m. 2 It can withstand 10-20 bends.

[0031] In Examples 1-3, the melt flow rate of PC gradually increases, the flexural modulus of the composition gradually increases, the impact strength gradually decreases, and the bending resistance slightly decreases. It can be seen that PC has better rigidity, toughness and bending resistance when the melt flow rate is in the range of 1-30 g / 10 min.

[0032] In Examples 6, 5, 2, and 4, with the same total weight of PC and Si-PC, the mass ratios of PC to Si-PC were 1.25:1, 3.5:1, 5:1, and 8:1, respectively. As the PC content increased, the Si-PC content decreased, and the flexural modulus of the composition gradually increased, the impact strength gradually decreased, and the bending resistance gradually deteriorated. It is evident that when the mass ratio of PC to Si-PC is within the range of (1-8):1, the composition exhibits superior rigidity, toughness, and bending resistance.

[0033] In Examples 7, 2, and 8, the silicon content in Si-PC was 3 wt%, 8 wt%, and 20 wt%, respectively. As the silicon content increased, the flexural modulus of the composition gradually decreased, the impact strength gradually increased, and the bending resistance slightly deteriorated. Therefore, when the silicon content in Si-PC is in the range of 3 wt%-22 wt%, the composition exhibits superior rigidity, toughness, and bending resistance.

[0034] In Examples 9, 2, and 10, the MA content in EMA was 18 wt%, 28 wt%, and 35 wt%, respectively. As the MA content increased, the flexural modulus of the composition gradually decreased, the impact strength gradually increased, and the bending resistance gradually deteriorated. It is evident that when the MA content in EMA is within the range of 18 wt%-35 wt%, the composition exhibits superior rigidity, toughness, and bending resistance.

[0035] In Examples 11, 2, and 12, with the same total weight of EMA and silicone toughening agent, the mass ratios of EMA to silicone toughening agent were 1:1, 2:1, and 3.5:1, respectively. As the EMA content increased, the silicone toughening agent content decreased, and the flexural modulus of the composition gradually increased, the impact strength gradually decreased, and the bending resistance gradually improved. It is evident that when the mass ratio of EMA to silicone toughening agent is within the range of (1-3.5:1), the composition exhibits superior rigidity, toughness, and bending resistance.

[0036] In Examples 15, 2, and 16, the Si content in the organosilicon toughening agent was 6 wt%, 8 wt%, and 30 wt%, respectively. As the Si content increased, the flexural modulus of the composition gradually decreased, the impact strength gradually increased, and the bending resistance deteriorated. It is evident that when the silicon content in the organosilicon toughening agent is in the range of 6-30 wt%, the composition exhibits superior rigidity, toughness, and bending resistance.

[0037] Comparing Comparative Examples 1-5 with Example 2, Comparative Example 1 contained no Si-PC and the total amount of PC was the same as in Example 2. Comparative Example 2 contained no Si-PC, EMA, or silicone toughening agent and the total amount of PC was the same as in Example 2. Comparative Example 3 contained no EMA. Comparative Example 4 contained no silicone toughening agent and its total amount was the same as the total amount of EMA and silicone toughening agent in Example 2. Comparative Example 5 used other toughening agents. None of the compositions in Comparative Examples 1-5 could achieve a balance of rigidity, toughness, and bending resistance.

[0038] 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 polycarbonate composition, characterized in that, It includes the following components in parts by weight: PC resin 58-96, silicone copolymer polycarbonate 9-41 parts, ethylene-methyl acrylate copolymer 0.9-6 parts, silicone toughening agent 0.5-4.5 parts, glass fiber 9-31 parts.

2. The polycarbonate composition according to claim 1, characterized in that, The melt flow rate of the PC resin is 1-30 g / 10 min. The melt flow rate is tested according to ISO 1133-1 2011 standard, and the test conditions are 300℃ and 1.2 kg.

3. The polycarbonate composition according to claim 1, characterized in that, The silicon copolymer polycarbonate contains 3%-22% silicon by mass.

4. The polycarbonate composition according to claim 1, characterized in that, The ethylene-methyl acrylate copolymer contains 18%-35% methyl acrylate segments by mass.

5. The polycarbonate composition according to claim 1, characterized in that, The mass ratio of the ethylene-methyl acrylate copolymer to the organosilicon toughening agent is (1-3.5):1; And / or, the mass ratio of the PC resin to the silicon copolycarbonate is (1-8):

1.

6. The polycarbonate composition according to claim 1, characterized in that, The organosilicon toughening agent has a core-shell structure, with its core comprising siloxane and its shell comprising acrylate.

7. The polycarbonate composition according to claim 6, characterized in that, The organosilicon toughening agent contains 6%-30% silicon by mass.

8. The polycarbonate composition according to claim 1, characterized in that, It also includes processing aids, which comprise the following components in parts by weight: 0.1-1.5 parts antioxidant and 0.1-1.5 parts lubricant.

9. A method for preparing the polycarbonate composition according to any one of claims 1-8, characterized in that, The process includes the following steps: mixing, melting, extruding, and granulating the raw materials in sequence to obtain the polycarbonate composition.

10. The use of a polycarbonate composition according to any one of claims 1-8 in the manufacture of mobile phones and robots.

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