High-gloss scratch-resistant PPO-PA alloy material and preparation method thereof

Abstract

The invention discloses a high-gloss scratch-resistant PPO-PA alloy material and a preparation method thereof. The high-gloss scratch-resistant PPO-PA alloy material is prepared from the following components in parts by weight: 30 to 45 parts of polyphenyl ether, 25 to 40 parts of polyamide, 2 to 8 parts of surface modified nano silicon dioxide, 3 to 10 parts of methyl phenyl organic silicon resin, 3 to 8 parts of compatilizer, 0.2 to 0.6 part of antioxidant and 0.3 to 0.8 part of lubricant. The surface modified nano silicon dioxide is adopted, the nano-scale particle size can avoid surface roughness, meanwhile, the surface hardness is improved through particle reinforcement, silane groups, PPO and PA can form weak bond action, and dispersion uniformity is guaranteed; the scratch resistance is improved by introducing the surface modified nano silicon dioxide, the surface highlight performance is optimized by means of the methyl phenyl organic silicon resin, meanwhile, the content of all the components and technological parameters are controlled, the comprehensive performance of the alloy material is guaranteed, and the alloy material has the highlight appearance, the excellent scratch resistance and the comprehensive mechanical performance.

Description

Technical Field

[0001] This invention belongs to the field of polymer composite materials technology, specifically relating to a high-gloss, scratch-resistant PPO-PA alloy material and its preparation method. Background Technology

[0002] Polyphenylene oxide (PPO) is a high-performance thermoplastic engineering plastic with outstanding heat resistance, excellent dimensional stability, and electrical insulation. It also exhibits good hydrolytic resistance and chemical stability, making it widely used in electronics, automotive, and other fields. However, pure PPO suffers from drawbacks such as poor melt flowability, high processing difficulty, and insufficient solvent resistance, which limits its use on its own.

[0003] Polyamide (PA), as another mainstream engineering plastic, possesses high mechanical strength, good solvent resistance, and processing fluidity, and its cost is relatively low, which can compensate for the processing defects of PPO. Therefore, PPO-PA alloys, formed by blending PPO and PA, can achieve a complementary advantage between the heat resistance / dimensional stability of PPO and the mechanical / processability of PA, and have become an important direction in the field of modified plastics. They are currently widely used in automotive electrical connectors, mechanical parts, and other applications.

[0004] However, existing PPO-PA alloys have the disadvantage of insufficient surface properties. Traditional fillers (such as talc) result in rough surfaces, low gloss, and low surface hardness (pencil hardness B~HB), which makes it difficult to meet the requirements of appearance parts. Secondly, compatibility control is complicated. Some solutions use compound compatibilizers, which can improve interfacial bonding, but increase the complexity of the formulation and production costs. Moreover, in the application of existing single compatibilizers, the mechanical properties and surface properties are difficult to achieve simultaneously due to insufficient interfacial interaction.

[0005] Traditional PPO-PA alloys often incorporate fillers such as talc and calcium carbonate to enhance rigidity. However, these fillers have relatively large particle sizes (typically ≥1000 mesh), which can lead to a rough surface and low gloss, failing to achieve a "high-gloss" effect. Adding silicone-based additives to improve gloss can result in poor compatibility, leading to material delamination or a decrease in mechanical properties. Furthermore, existing alloys have low surface hardness (pencil hardness is mostly B~HB), making them easily scratched during daily use, affecting the durability of their appearance and failing to meet the requirement for "scratch resistance."

[0006] Chinese invention patent CN107118546 B discloses a nylon 6 / polyphenylene ether composition that improves mechanical properties through calcium chloride and a compatibilizer, but does not address surface gloss and scratch resistance modification. Chinese invention patent CN115466506 B focuses on the dimensional stability of PPO-nylon composite materials for new energy electrical boxes, but similarly fails to address the surface performance issue.

[0007] Therefore, developing a PPO-PA alloy that combines a high-gloss appearance, excellent scratch resistance, and comprehensive mechanical properties is key to expanding its application areas. Summary of the Invention

[0008] To address the problems in the prior art, the present invention aims to provide a high-gloss, scratch-resistant PPO-PA alloy material and its preparation method. By introducing surface-modified nano-silica to improve scratch resistance, and by using methylphenyl silicone resin to optimize the surface gloss, the content of each component and process parameters are controlled to ensure the comprehensive performance of the alloy material, which has a high-gloss appearance, excellent scratch resistance and comprehensive mechanical properties.

[0009] To achieve the above objectives and technical effects, the technical solution adopted by this invention is as follows: A high-gloss, scratch-resistant PPO-PA alloy material, comprising the following components in parts by weight: 30-45 parts of polyphenylene ether 25-40 parts of polyamide Surface-modified nano silica 2-8 parts 3-10 parts of methylphenyl silicone resin 3-8 parts compatibilizer Antioxidant 0.2-0.6 parts Lubricant 0.3-0.8 parts.

[0010] Furthermore, the characteristic viscosity of the polyphenylene ether is 0.35-0.65 dL / g.

[0011] Furthermore, the polyamide is at least one of PA6 and PA66.

[0012] Furthermore, the relative viscosity of PA6 is 2.2-3.5; and the relative viscosity of PA66 is 2.4-3.8.

[0013] Furthermore, the surface-modified nano-silica has an average particle size of 10-50 nm and is obtained by modifying nano-silica with γ-aminopropyltriethoxysilane.

[0014] Furthermore, the number average molecular weight of the methylphenyl silicone resin is 5000-15000 g / mol.

[0015] Furthermore, the compatibilizer is PPO-g-MAH.

[0016] Furthermore, the antioxidant is a compound of antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]) and antioxidant 168 (tris[2,4-di-tert-butylphenyl]phosphite), with a weight ratio of 1:1-2.

[0017] Furthermore, the lubricant is at least one of pentaerythritol stearate (PETS) and vinyl bis-stearamide (EBS).

[0018] This invention also discloses a method for preparing a high-gloss, scratch-resistant PPO-PA alloy material, comprising the following steps: (1) Raw material pretreatment: Dry polyphenylene ether and polyamide at 100-120℃ for 4-6 hours to remove moisture; (2) Premixing: Add polyphenylene ether, polyamide, surface-modified nano silica, methyl phenyl silicone resin, compatibilizer, antioxidant and lubricant to a high-speed mixer and mix for 5-8 minutes at 30-50℃ and 300-500r / min to obtain a premix; (3) Extrusion granulation: Add the premixed material to the twin-screw extruder, control the screw speed to 150-250 r / min and the feeder speed to 15-30 r / min, and the temperature of each section of the extruder is: 220-230℃ for the feeding section, 230-245℃ for the melting section and 245-260℃ for the homogenization section. After melt extrusion, the material is cooled by water and granulated to obtain high-gloss and scratch-resistant PPO-PA alloy material.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention uses surface-modified nano silica. The nano-sized particle size can avoid surface roughness, and at the same time, the surface hardness is improved by "particle reinforcement". Its silane groups can form weak bond effects with PPO and PA, ensuring uniform dispersion. (2) The silicon-oxygen bonds in the methylphenyl organosilicon resin used in this invention can reduce surface tension, form a smooth surface, and improve gloss, thereby achieving a "high gloss" effect; adding lubricant can reduce friction between the screw and the raw material, avoid surface defects during processing, and further optimize the "high gloss" effect; (3) The compatibilizer of the present invention adopts PPO-g-MAH, which significantly improves the interfacial compatibility of the alloy material system. Antioxidant 1010 and antioxidant 168 are compounded in a ratio of 1:1-2 to inhibit material aging during processing and use and ensure long-term performance. Detailed Implementation

[0020] The present invention will now be described in detail so that its advantages and features can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0021] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify key or decisive elements of all aspects, nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form to prepare for the more detailed descriptions that follow.

[0022] This invention discloses a high-gloss, scratch-resistant PPO-PA alloy material, comprising the following components in parts by weight: 30-45 parts of polyphenylene oxide (PPO) Polyamide (PA) 25-40 parts Surface-modified nano silica 2-8 parts 3-10 parts of methylphenyl silicone resin 3-8 parts compatibilizer Antioxidant 0.2-0.6 parts Lubricant 0.3-0.8 parts.

[0023] In some implementations, the characteristic viscosity of PPO is 0.35-0.65 dL / g.

[0024] In some implementations, PA is at least one of PA6 and PA66.

[0025] In some more specific embodiments, the relative viscosity of PA6 is 2.2-3.5.

[0026] In some more specific embodiments, the relative viscosity of PA66 is 2.4-3.8.

[0027] In some embodiments, the surface-modified nano-silica has an average particle size of 10-50 nm and is obtained by modifying nano-silica with γ-aminopropyltriethoxysilane.

[0028] In some embodiments, the number average molecular weight of the methylphenyl silicone resin is 5000-15000 g / mol.

[0029] In some embodiments, the compatibilizer is PPO-g-MAH.

[0030] In some embodiments, the antioxidant is a compound of antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]) and antioxidant 168 (tris[2,4-di-tert-butylphenyl]phosphite) in a weight ratio of 1:1-2.

[0031] In some embodiments, the lubricant is at least one of pentaerythritol stearate (PETS) and vinyl bis-stearamide (EBS).

[0032] This invention also discloses a method for preparing a high-gloss, scratch-resistant PPO-PA alloy material, comprising the following steps: (1) Raw material pretreatment: Dry PPO and PA at 100-120℃ for 4-6 hours to remove moisture; (2) Premixing: Add the pretreated PPO, PA, surface-modified nano silica, methyl phenyl silicone resin, compatibilizer, antioxidant, and lubricant to a high-speed mixer and mix for 5-8 minutes at 30-50℃ and 300-500r / min to obtain a uniform premix. (3) Extrusion granulation: Add the premixed material to the twin-screw extruder, control the screw speed to 150-250 r / min and the feeder speed to 15-30 r / min, and the temperature of each section of the extruder is: 220-230℃ for the feeding section, 230-245℃ for the melting section and 245-260℃ for the homogenization section. After melt extrusion, the material is cooled by water and granulated to obtain high-gloss and scratch-resistant PPO-PA alloy material.

[0033] In some implementations, the twin-screw extruder has a length-to-diameter ratio of 35-45:1 and a screw diameter of 25-35 mm.

[0034] Example 1 A high-gloss, scratch-resistant PPO-PA alloy material, comprising the following components in parts by weight: 35 parts of polyphenylene oxide (PPO) 32 parts of polyamide (PA) 4 parts of surface-modified nano-silica 6 parts of methylphenyl silicone resin 5 parts compatibilizer Antioxidant 0.4 parts 0.6 parts of lubricant.

[0035] In this embodiment, the PPO used is Bluestar Chemical LXR040, with an characteristic viscosity of 0.4 dL / g, and tested in chloroform solvent at 25°C.

[0036] PA is PA6, using Xinhui Meda M2800, with a relative viscosity of 2.8.

[0037] The surface-modified nano-silica has an average particle size of 10 nm and is obtained by modifying nano-silica with γ-aminopropyltriethoxysilane using Evonik AEROSIL R972.

[0038] The methylphenyl silicone resin used is Wacker SILRES HP2000, with a number average molecular weight of 5000 g / mol.

[0039] The compatibilizer is PPO-g-MAH, Idemitsu CX-1 from Japan.

[0040] The antioxidant is a compound of antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]) and antioxidant 168 (tris[2,4-di-tert-butylphenyl]phosphite) in a weight ratio of 1:1.

[0041] The lubricant was pentaerythritol stearate (PETS), purchased from Shanghai Huijun Chemical Co., Ltd.

[0042] A method for preparing a high-gloss, scratch-resistant PPO-PA alloy material includes the following steps: (1) Raw material pretreatment: PPO and PA are dried at 100℃ for 5 hours to remove moisture; (2) Premixing: The pretreated PPO, PA, surface-modified nano silica, methyl phenyl silicone resin, compatibilizer, antioxidant and lubricant are added to a high-speed mixer and mixed for 6 minutes at 40℃ and 400r / min to obtain a uniform premix. (3) Extrusion granulation: The premixed material is added to a twin-screw extruder, and the screw speed is controlled at 200 r / min and the feeder speed at 20 r / min. The temperatures of each section of the extruder are: 220℃ for the feeding section, 240℃ for the melting section, and 250℃ for the homogenization section. After melt extrusion, the material is cooled by water and granulated to obtain high-gloss scratch-resistant PPO-PA alloy material.

[0043] The twin-screw extruder has a length-to-diameter ratio of 35:1 and a screw diameter of 25mm.

[0044] The formulations of Examples 1-4 and Comparative Examples 1-3 are shown in Table 1.

[0045] Table 1 In Example 3, PA66 was Yuehua EPR27 with a relative viscosity of 3.

[0046] The prepared materials were tested for surface gloss, pencil hardness, tensile strength, impact strength, and heat distortion temperature, respectively, according to the standards or methods described below: Surface gloss: GB / T 8807-2008 (60° angle); Pencil hardness: GB / T 6739-2021 (load 750g); Tensile strength: GB / T 1040.2-2006 (tensile speed 50mm / min); Notched impact strength of cantilever beam: GB / T 1843-2008 (23℃, notch type A); Heat distortion temperature: GB / T 1634.2-2019 (0.45MPa, heating rate 2℃ / min).

[0047] The test results are shown in Table 2.

[0048] Table 2 As shown in Table 2, Examples 1-4 all meet the requirements of "gloss ≥ 88, hardness ≥ H, tensile strength ≥ 64 MPa, and impact strength ≥ 16 MPa", proving that the obtained high-gloss, scratch-resistant PPO-PA alloy material achieves excellent high gloss, scratch resistance, and mechanical properties. Comparative Example 1, without surface-modified nano-silica, shows a decrease in pencil hardness to grade B and a significant reduction in scratch resistance, indicating that surface nano-silica is key to improving scratch resistance. Comparative Example 2, without methylphenyl silicone resin, has a gloss of only 73%, indicating a failure of high gloss performance, demonstrating that methylphenyl silicone resin can reduce surface tension. Comparative Example 3, without compatibilizer, shows a decrease in tensile strength to 52 MPa and impact strength to 10 kJ / m. 2 Furthermore, the heat resistance decreased slightly, proving that the decrease in compatibility has a negative impact on mechanical properties.

[0049] The high-gloss, scratch-resistant PPO-PA alloy material obtained by this invention has controllable raw material costs, and the product can be directly used in the fields of household appliance shells (such as refrigerator panels) and automotive interiors (such as center console panels).

[0050] Any parts or structures not specifically described in this invention can be made using existing technologies or products, and will not be elaborated upon here.

[0051] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A high-gloss, scratch-resistant PPO-PA alloy material, characterized in that, The components include the following parts by weight: 30-45 parts of polyphenylene ether 25-40 parts of polyamide Surface-modified nano silica 2-8 parts 3-10 parts of methylphenyl silicone resin 3-8 parts compatibilizer Antioxidant 0.2-0.6 parts Lubricant 0.3-0.8 parts.

2. The high-gloss, scratch-resistant PPO-PA alloy material according to claim 1, characterized in that, The characteristic viscosity of the polyphenylene ether is 0.35-0.65 dL / g.

3. The high-gloss, scratch-resistant PPO-PA alloy material according to claim 1, characterized in that, The polyamide is at least one of PA6 and PA66.

4. The high-gloss, scratch-resistant PPO-PA alloy material according to claim 3, characterized in that, The relative viscosity of PA6 is 2.2-3.5; the relative viscosity of PA66 is 2.4-3.

8.

5. The high-gloss, scratch-resistant PPO-PA alloy material according to claim 1, characterized in that, The surface-modified nano-silica has an average particle size of 10-50 nm and is obtained by modifying nano-silica with γ-aminopropyltriethoxysilane.

6. The high-gloss, scratch-resistant PPO-PA alloy material according to claim 1, characterized in that, The number-average molecular weight of the methylphenyl silicone resin is 5000-15000 g / mol.

7. The high-gloss, scratch-resistant PPO-PA alloy material according to claim 1, characterized in that, The compatibilizer is PPO-g-MAH.

8. The high-gloss, scratch-resistant PPO-PA alloy material according to claim 1, characterized in that, The antioxidant is a compound of antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]) and antioxidant 168 (tris[2,4-di-tert-butylphenyl]phosphite), with a weight ratio of 1:1-2.

9. The high-gloss, scratch-resistant PPO-PA alloy material according to claim 1, characterized in that, The lubricant is at least one of pentaerythritol stearate (PETS) and vinyl bis-stearamide (EBS).

10. A method for preparing a high-gloss, scratch-resistant PPO-PA alloy material according to any one of claims 1-9, characterized in that, Includes the following steps: (1) Raw material pretreatment: Dry polyphenylene ether and polyamide at 100-120℃ for 4-6 hours to remove moisture; (2) Premixing: Add polyphenylene ether, polyamide, surface-modified nano silica, methyl phenyl silicone resin, compatibilizer, antioxidant and lubricant to a high-speed mixer and mix for 5-8 minutes at 30-50℃ and 300-500r / min to obtain a premix; (3) Extrusion granulation: Add the premixed material to the twin-screw extruder, control the screw speed to 150-250 r / min and the feeder speed to 15-30 r / min, and the temperature of each section of the extruder is: 220-230℃ for the feeding section, 230-245℃ for the melting section and 245-260℃ for the homogenization section. After melt extrusion, the material is cooled by water and granulated to obtain high-gloss and scratch-resistant PPO-PA alloy material.

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