On-line spraying PPO / PA alloy material and preparation method thereof

Abstract

The invention relates to the technical field of coatings, in particular to an on-line spraying PPO / PA alloy material and a preparation method thereof.The on-line spraying PPO / PA alloy material is prepared from, by weight, 40-50 parts of PA66, 30-40 parts of PPO, 4-8 parts of compatilizer A, 0.2-1 part of compatilizer B, 10-20 parts of SBS, 1-3 parts of conductive agent and 0.2-1 part of auxiliaries. Compared with the prior art, the on-line spraying PPO / PA alloy material has the beneficial effects that the on-line spraying PPO / PA alloy material is obtained by blending the compatilizer A (maleic anhydride grafted polyphenyl ether), the compatilizer B, the SBS, the conductive agent and the assistant on the basis of PPO and PA, has good mechanical properties, conductivity and flowing properties, and can meet the use requirements of on-line spraying.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to an online spraying PPO / PA alloy material and a preparation method thereof. Background Art

[0002] Online spraying is a process in which parts are sprayed together with the entire vehicle in the paint shop, while offline spraying is a process in which individual parts are sprayed and then installed on the entire vehicle. Both include the process of spraying primer and topcoat (color paint and varnish). The biggest difference lies in the baking process temperature. The drying temperature of offline spraying is 80-90℃ (about 30 minutes), and the drying temperature of online spraying is 140-160℃ (about 30 minutes).

[0003] Online spraying is a process of spraying parts together with the vehicle, so the parts match the vehicle body without color difference, and the appearance is beautiful, delicate, and high-grade. The color difference is easy to control, the defective rate is low, the quality management cost is low, and there is no color matching problem. It can save color development costs, save packaging and transportation costs, and have a low overall cost, energy saving and environmental protection.

[0004] However, the online spraying process has relatively high requirements on the heat resistance of the substrate, and there are relatively fewer substrate materials suitable for the offline spraying process. At the same time, online spraying also requires the raw materials to have a certain conductivity and fluidity to prevent static electricity from being generated during the online spraying process, which affects the spraying effect. Summary of the Invention

[0005] In order to solve the problems mentioned in the above background technology, the present invention provides an online spraying PPO / PA alloy material and a preparation method thereof.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: An online spraying PPO / PA alloy material comprises, by weight, 40-50 parts of PA66, 30-40 parts of PPO, 4-8 parts of compatibilizer A, 0.2-1 part of compatibilizer B, 10-20 parts of SBS, 1-3 parts of conductive agent, and 0.2-1 part of auxiliary agent.

[0007] Preferably, the compatibilizer A is maleic anhydride grafted polyphenylene ether, and the grafting rate is 1-3 wt%.

[0008] Preferably, the preparation method of the compatibilizer B is: Under a nitrogen environment, diethylenetriamine, 4-methylphthalic anhydride, and p-toluenesulfonic acid were mixed and stirred uniformly, heated for reaction, 3-diethylenetriaminopropylmethyldimethoxysilane was added, and the reaction was continued. After the reaction was completed, the mixture was cooled to obtain a compatibilizer B.

[0009] Preferably, the preparation method of the conductive agent is as follows: The carbon nanotubes are added to the mixed acid solution, ultrasonically dispersed, heated under reflux for reaction, deionized water is added to form a suspension, and centrifuged to obtain a conductive agent.

[0010] Preferably, the other additives include lubricants and antioxidants.

[0011] Preferably, the lubricant is any one or both of PE wax and PP wax.

[0012] Preferably, the antioxidant is any one or both of antioxidant 168 and antioxidant 1098.

[0013] The present invention also provides a method for preparing the above-mentioned PPO / PA alloy material, comprising the following steps: S1. Weigh PA66, PPO, compatibilizer A, compatibilizer B, SBS, conductive agent, additives in parts by weight and mix well to obtain a mixture; S2. The above mixture is melt-extruded through a twin-screw extruder, cooled, dried, and pelletized to obtain a PPO / PA alloy material.

[0014] Preferably, the mixing conditions are: 400-600 rpm, 10-20 min.

[0015] Preferably, in step S2, the process conditions for melt extrusion are: the temperature of the first zone is 180°C, the temperature of the second zone is 250°C, the temperature of the third zone is 280°C, the temperature of the fourth zone is 280°C, the temperature of the fifth zone is 240°C, the temperature of the sixth zone is 260°C, the temperature of the seventh zone is 280°C, the temperature of the eighth zone is 280°C, the temperature of the ninth zone is 280°C, and the head temperature is 280°C.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. Based on PPO and PA, this application obtains an online spray-coated PPO / PA alloy material by blending compatibilizer A (maleic anhydride grafted polyphenylene ether), compatibilizer B, SBS, a conductive agent, and an additive. The material has good mechanical properties, conductive properties, and flow properties, and can meet the requirements of online spraying.

[0017] 2. The present invention utilizes a combination of compatibilizers A and B. Compatibilizer A improves the compatibility between PPO and PA66, reduces interfacial tension between the two phases, allows for better dispersion and bonding between the two phases, and enhances the mechanical properties and stability of the alloy. Compatibilizer B's molecular structure contains multiple functional groups, including amino, carboxyl, and silane groups. The amino and carboxyl groups can form hydrogen bonds or react with the amide groups of PA66 and the anhydride groups of compatibilizer A, enhancing their interaction with PA66. The silane groups can chemically react or physically entangle with PPO, thereby acting as a bridge between the two phases and further enhancing their compatibility.

[0018] 3. By subjecting carbon nanotubes to mixed acid treatment (a mixed solution of sulfuric acid and nitric acid), a large number of oxygen-containing functional groups, such as hydroxyl and carboxyl groups, are introduced onto their surface. These functional groups not only improve the dispersion of carbon nanotubes in the matrix, but also undergo cross-linking reactions with compatibilizers A, B and polymers during melt extrusion, thereby improving the compatibility of PPO and PA and promoting the dispersion effect of the conductive agent. As a result, the alloy material can have good electrical conductivity at a relatively low addition amount, which can meet application scenarios such as online spraying that require material conductivity. DETAILED DESCRIPTION

[0019] Unless otherwise specified, the raw materials and reagents used in the present invention are commercially available or can be prepared by known methods.

[0020] PA66: Rhodia, France, A205F; PPO: Bluestar Chemical, LXR045; Maleic anhydride grafted polyphenylene ether (compatibilizer A): Shenyang Ketong Plastic Co., Ltd.; SBS: Sinopec Baling, YH-792; Carbon nanotubes, Jiangsu Xianfeng Nanomaterial Technology Co., Ltd., 100252; Antioxidant 168, Antioxidant 1098: BASF; Lubricant: Clariant, wax powder PE520.

[0021] The preparation method of compatibilizer B is: Under nitrogen environment, 1 mol of diethylenetriamine and 2 mol of 4-methylphthalic anhydride were mixed evenly, 0.01 mol of p-toluenesulfonic acid was added, the temperature was gradually raised to 220°C, the reaction was carried out for 3 hours, 0.1 mol of 3-diethylenetriaminopropylmethyldimethoxysilane was added, and the reaction was continued for 2 hours. After the reaction was completed, it was cooled to room temperature, the product was dissolved in dimethyl sulfoxide, and slowly added to a large amount of water to obtain flocs. The flocs were centrifuged, washed with water, and dried to obtain compatibilizer B.

[0022] The preparation method of the conductive agent is as follows: 100 g of carbon nanotubes were added to a mixed acid solution (1.5 L H2SO4 + 0.5 L HNO3), ultrasonically dispersed, refluxed at 60°C for 3 h, deionized water was added to form a suspension, centrifuged, and dried to obtain a conductive agent. Example 1

[0023] An online spray-coated PPO / PA alloy material comprises, by weight, 45 parts of PA66, 35 parts of PPO, 6 parts of compatibilizer A (maleic anhydride grafted polyphenylene ether, grafting rate 1.5wt%), 0.6 parts of compatibilizer B, 15 parts of SBS, 2 parts of conductive agent, 0.3 parts of antioxidant 168, and 0.3 parts of wax powder PE520.

[0024] Preparation method of PPO / PA alloy material: S1. Weigh PA66, PPO, compatibilizer A, compatibilizer B, SBS, conductive agent, additives in parts by weight and mix well to obtain a mixture; S2. The above mixture is melt-extruded through a twin-screw extruder, cooled, dried, and pelletized to obtain a PPO / PA alloy material.

[0025] In step S1, the conditions for uniform mixing are: 500 rpm, 15 min.

[0026] In step S2, the process conditions for melt extrusion are: the temperature of the first zone is 180°C, the temperature of the second zone is 250°C, the temperature of the third zone is 280°C, the temperature of the fourth zone is 280°C, the temperature of the fifth zone is 240°C, the temperature of the sixth zone is 260°C, the temperature of the seventh zone is 280°C, the temperature of the eighth zone is 280°C, the temperature of the ninth zone is 280°C, and the head temperature is 280°C. Example 2

[0027] The difference between this embodiment and embodiment 1 is that the amount of PA66 is 40 parts, and the rest of the ingredients are exactly the same as those in embodiment 1. Example 3

[0028] The difference between this embodiment and embodiment 1 is that the amount of PA66 is 50 parts, and the rest of the ingredients are exactly the same as those in embodiment 1. Example 4

[0029] The difference between this embodiment and embodiment 1 is that the amount of compatibilizer B is 0.2 parts, and the rest of the components are exactly the same as those in embodiment 1. Example 5

[0030] The difference between this embodiment and embodiment 1 is that the amount of compatibilizer B is 1 part, and the rest of the components are exactly the same as those in embodiment 1. Example 6

[0031] The difference between this embodiment and embodiment 1 is that the conductive agent is 1 part, and the rest of the parts are exactly the same as those in embodiment 1. Example 7

[0032] The difference between this embodiment and embodiment 1 is that the conductive agent is 3 parts, and the rest is exactly the same as embodiment 1.

[0033] Comparative Example 1 The difference between this comparative example and Example 1 is that the amount of compatibilizer B is 0 parts, and the rest of the components are exactly the same as those in Example 1.

[0034] Comparative Example 2 The difference between this comparative example and Example 1 is that 2 parts of compatibilizer B are used, and the rest of the components are exactly the same as those in Example 1.

[0035] Comparative Example 3 The difference between this comparative example and Example 1 is that the carbon nanotubes are 2 parts, and the rest are exactly the same as in Example 1.

[0036] Comparative Example 4 The difference between this comparative example and Example 1 is that in step S2, the process conditions of melt extrusion are: the temperature of the first zone is 180°C, the temperature of the second zone is 250°C, the temperature of the third zone is 280°C, the temperature of the fourth zone is 280°C, the temperature of the fifth zone is 280°C, the temperature of the sixth zone is 280°C, the temperature of the seventh zone is 280°C, the temperature of the eighth zone is 280°C, the temperature of the ninth zone is 280°C, and the temperature of the die is 280°C. The rest is exactly the same as in Example 1.

[0037] Results and Testing Bend test: ISO 178:2019, specimen: 80 mm x 10.024 mm x 3.987 mm, test speed: 2 mm / min, span: 64 mm, laboratory environmental conditions: (23 ± 2) °C, (50 ± 5)% RH; Volume resistivity: IEC 62631-3-1:2023, preconditioning conditions: (23+2)°C, (50+5)%RH, 96 h, test electrodes: D50 mm, D2=60 mm, test voltage: 100 Vdc, test time: 1 min, laboratory ambient conditions: (23+2)°C, (50+5)%RH; Vicat softening temperature: ISO 306:2022, sample thickness: 4.000 mm, liquid heat transfer medium: silicone oil, heating rate: 120°C / h, load: 50N; Tensile test: ISO 527-2:2012, specimen thickness: 3.986 mm, test speed: 50 mm / min, gauge length: 75 mm, initial grip spacing: 115 mm, laboratory environmental conditions: (23 ± 2) °C, (50 ± 5)% RH; Melt mass flow rate: ISO 1133-1:2022, drying temperature: 120°C, drying time: 12 h, test temperature: 280°C, test load: 5 kg.

[0038] The results are shown in Table 1.

[0039] Table 1

[0040] From the data in Table 1, it can be seen that the materials prepared in Examples 1-7 have good mechanical properties, electrical conductivity and flow properties, and can meet the requirements of online spraying.

[0041] Comparison of Example 1 and Comparative Examples 1 and 2 shows that the use of compatibilizer A (Comparative Example 1) alone or excessive use of compatibilizer B will lead to reduced material performance.

[0042] Comparing Example 1 with Comparative Example 3, it can be seen that after the mixed acid treatment, the carbon nanotubes contain functional groups such as hydroxyl and carboxyl groups on their surfaces, which can undergo cross-linking reaction with compatibilizer A and compatibilizer B to improve material properties.

[0043] Comparing Examples 1 and 4, it can be seen that by adjusting the temperature parameters during melt extrusion, it is unexpectedly found that the performance of the product can be appropriately improved.

[0044] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. An online spraying PPO / PA alloy material, characterized in that, Calculated by weight, it includes 40-50 parts of PA66, 30-40 parts of PPO, 4-8 parts of compatibilizer A, 0.2-1 part of compatibilizer B, 10-20 parts of SBS, 1-3 parts of conductive agent, and 0.2-1 part of auxiliary agent.

2. The online spraying PPO / PA alloy material according to claim 1, characterized in that: The compatibilizer A is maleic anhydride grafted polyphenylene ether, and the grafting rate is 1-3 wt%.

3. The online spraying PPO / PA alloy material according to claim 1, characterized in that: The preparation method of the compatibilizer B is: Under a nitrogen environment, diethylenetriamine, 4-methylphthalic anhydride, and p-toluenesulfonic acid were mixed and stirred uniformly, heated for reaction, 3-diethylenetriaminopropylmethyldimethoxysilane was added, and the reaction was continued. After the reaction was completed, the mixture was cooled to obtain a compatibilizer B.

4. The online spraying PPO / PA alloy material according to claim 1, characterized in that: The preparation method of the conductive agent is as follows: The carbon nanotubes are added to the mixed acid solution, ultrasonically dispersed, heated under reflux for reaction, deionized water is added to form a suspension, and centrifuged to obtain a conductive agent.

5. The online spraying PPO / PA alloy material according to claim 1, characterized in that: The other adjuvants include lubricants and antioxidants.

6. The online spraying PPO / PA alloy material according to claim 5, characterized in that: The lubricant is any one or both of PE wax and PP wax.

7. The online spraying PPO / PA alloy material according to claim 5, characterized in that: The antioxidant is any one or both of antioxidant 168 and antioxidant 1098.

8. A method for preparing the PPO / PA alloy material according to any one of claims 1 to 7, characterized in that: The steps include: S1. Weigh PA66, PPO, compatibilizer A, compatibilizer B, SBS, conductive agent, additives in parts by weight and mix well to obtain a mixture; S2. The above mixture is melt-extruded through a twin-screw extruder, cooled, dried, and pelletized to obtain a PPO / PA alloy material.

9. The method for preparing the alloy material according to claim 8, wherein: In step S1, the conditions for uniform mixing are: 400-600 rpm, 10-20 min.

10. The method for preparing the alloy material according to claim 8, characterized in that: In step S2, the process conditions for melt extrusion are: the temperature of the first zone is 180°C, the temperature of the second zone is 250°C, the temperature of the third zone is 280°C, the temperature of the fourth zone is 280°C, the temperature of the fifth zone is 240°C, the temperature of the sixth zone is 260°C, the temperature of the seventh zone is 280°C, the temperature of the eighth zone is 280°C, the temperature of the ninth zone is 280°C, and the head temperature is 280°C.

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