Polyether sulfone coating and preparation method thereof

Abstract

The invention discloses a polyethersulfone coating which comprises the following components in parts by weight: 45-85 parts of chlorine-terminated polyethersulfone; 3 to 25 parts of hydroxyl-terminated polyether sulfone; 10-45 parts of a wear-resistant filler; 0.1 to 2 parts of a coupling agent; 80 to 150 parts of an organic solvent; and 120 to 220 parts of water. According to the invention, the chlorine-end polyether sulfone and the hydroxyl-end polyether sulfone with specific content and specific end group content are selected, so that the bonding effect of the polyether sulfone and a substrate can be adjusted, the hardness of the polyether sulfone material is further controlled, the baking resistance can be effectively improved, and meanwhile, the specific wear-resistant filler is introduced, so that the hardness can be improved, and the surface glossiness can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, in particular to a polyethersulfone coating and a preparation method thereof. Background Art

[0002] Polyethersulfone (PES) is a non-crystalline thermoplastic high-temperature resistant engineering plastic with excellent comprehensive performance. It is one of the few special engineering plastics currently in use. It has good heat aging resistance, environmental resistance, stiffness, strength, toughness, chemical and solvent resistance. It has very wide applications in electronic appliances, medical devices, non-stick pan coatings, baby and children's products, food, etc.

[0003] Polyethersulfone (PES) is a polymer material with excellent thermal stability, chemical stability, and mechanical properties, widely used in aerospace, automotive, electronics, and other fields. However, traditional PES coatings suffer from low gloss and pencil hardness, which limits its application in coatings. Summary of the Invention

[0004] The object of the present invention is to provide a polyethersulfone coating with high hardness, baking resistance and high gloss and a preparation method thereof.

[0005] The present invention is achieved through the following technical solutions: A polyethersulfone coating comprising the following components in parts by weight: 45-85 parts of chlorine-terminated polyethersulfone; 3-25 parts of hydroxy-terminated polyethersulfone; 10-45 parts of wear-resistant filler; 0.1-2 parts of coupling agent; 80-150 parts of organic solvent; 120-220 parts of water.

[0006] The chlorine-terminated polyethersulfone has a chlorine-terminated content greater than 7 mmol / kg (hydroxyl-terminated content less than 20 mmol / kg), preferably greater than or equal to 15 mmol / kg (hydroxyl-terminated content less than 12 mmol / kg), and more preferably greater than or equal to 17 mmol / kg (hydroxyl-terminated content less than 10 mmol / kg).

[0007] The hydroxyl end content of the hydroxyl-terminated polyethersulfone is less than 30 mmol / kg, preferably less than or equal to 24 mmol / kg, and more preferably less than or equal to 21 mmol / kg.

[0008] The molecular weight of the chlorine-terminated polyethersulfone is 38,000-60,000 Da, preferably 42,000-48,000 Da; the molecular weight of the hydroxyl-terminated polyethersulfone is 38,000-60,000 Da, preferably 42,000-48,000 Da.

[0009] Chloro-terminated polyethersulfone and hydroxyl-terminated polyethersulfone can be commercially available products or can be obtained by self-production. The self-production method includes but is not limited to the following methods: The preparation method of hydroxyl-terminated polyethersulfone is as follows: in a nitrogen-protected reactor, an appropriate amount of N-methylpyrrolidone is added, the temperature is raised to 80°C~150°C, and the reaction monomers 4-4'-dichlorodiphenyl sulfone and bisphenol A, a salt-forming agent sodium carbonate, and a dehydrating agent xylene are added in sequence, and then N-methylpyrrolidone is added to adjust the solid content of the system to 20%~45%, and the temperature is raised to 240°C~320°C. The polymerization reaction is carried out at a constant temperature for 2~8 hours. The polymerized sheet is precipitated in water and is obtained after being crushed, boiled in water, and purified by high-pressure alcohol boiling.

[0010] The preparation method of chlorine-terminated polyethersulfone is as follows: in a nitrogen-protected reactor, an appropriate amount of N-methylpyrrolidone is added, the temperature is raised to 80°C~150°C, and the reaction monomers 4-4'-dichlorodiphenyl sulfone and bisphenol A, a salt-forming agent sodium carbonate, and a dehydrating agent xylene are added in sequence, and then N-methylpyrrolidone is added to adjust the solid content of the system to 20%~45%, and a blocking agent (methyl chloride, methyl bromide, methyl iodide, etc.) is introduced, the temperature is raised to 240°C~320°C, and a constant temperature polymerization reaction is carried out for 2~8 hours. The polymer sheet is precipitated in water and is obtained after crushing, boiling in water, and purification by high-pressure alcohol boiling.

[0011] Test method for the content of hydroxyl and chlorine ends in polyethersulfone: The hydroxyl content of hydroxy-terminated polyethersulfone is calculated according to the following formula: X=(m1*2*1 000 000) / (m1M1) Wherein, X is the hydroxyl content of the hydroxy-terminated polyethersulfone, in mmol / kg; m1 is the mass of hydroxy polyethersulfone, in kg; M1 is the molecular weight of hydroxy polyethersulfone, in g / mol.

[0012] The chlorine content of chlorine-terminated polyethersulfone is obtained as follows: the hydroxyl value of chlorine-terminated polyethersulfone is determined according to the method of GB / T 12008.3-2009. Then the hydroxyl value is calculated according to the following formula: Y=(m2*2*1 000 000) / (m2M2)-Z Wherein, Y is the hydroxyl content of the chlorine-terminated polyethersulfone, unit: mmol / kg; m2 is the mass of chlorine-terminated polyethersulfone, in kg; M2 is the molecular weight of chlorine-terminated polyethersulfone, unit is g / mol Z is the hydroxyl content of chlorine-terminated polyethersulfone, unit: mmol / kg.

[0013] The wear-resistant filler is selected from at least one of barium sulfate, nano glass beads, silicon dioxide, aluminum oxide, silicon carbide, silicon nitride, polytetrafluoroethylene, and polyimide.

[0014] The mesh size range of the wear-resistant filler may be 2000-40000 mesh.

[0015] Preferably, the wear-resistant filler is a compound of barium sulfate and nano-glass microspheres in a weight ratio of (5-2): (3-1). The mesh size of the barium sulfate is in the range of 3000-5000 mesh; the mesh size of the nano-glass microspheres is in the range of 20000-30000 mesh.

[0016] The nano glass microspheres are selected from at least one of hollow glass microspheres and solid glass microspheres.

[0017] The organic solvent is selected from at least one of N-methylpyrrolidone, sulfolane, N,N'-dimethylacetamide and N,N'-dimethylformamide.

[0018] The coupling agent is selected from silane coupling agents.

[0019] Without affecting the purpose of the present invention, those skilled in the art may appropriately add the following substances to modify the polyethersulfone coating of the present invention, such as one or more of 0.1 part abrasive, 0-0.5 part antioxidant, 0-2 parts lubricant, 0-0.8 part nucleating agent, 0-3 parts crosslinking agent, etc.

[0020] The abrasive can be zirconia beads, corundum, silicon carbide, boron carbide, artificial diamond, etc.

[0021] The antioxidant may be coating antioxidant 168, antioxidant 1010, antioxidant 1098, BHT (264), TNPP, etc.; The lubricant can be molybdenum disulfide, graphite, lead oxide, sodium molybdate, polytetrafluoroethylene, lubricating oil, etc. The nucleating agent can be dimethicone and its derivatives, metal phosphates, talc, calcium carbonate, silicon dioxide, titanium dioxide, calcium oxide, magnesium oxide, mica, etc. The cross-linking agent can be an amino resin cross-linking agent, a coating printing cross-linking agent, a self-cross-linking adhesive, etc.

[0022] The preparation method of the polyethersulfone coating of the present invention comprises the following steps: pre-treating a coupling agent, a grinding agent and nano glass microbeads, grinding them with chlorine-terminated polyethersulfone, hydroxyl-terminated polyethersulfone, a grinding agent, an organic solvent and water, and filtering them through a filter to obtain the polyethersulfone coating.

[0023] The grinding time may be 40-60 hours.

[0024] The present invention has the following beneficial effects: By selecting chlorine-terminated polyethersulfone and hydroxyl-terminated polyethersulfone with specific contents and specific end group contents, the present invention can adjust the adhesion between polyethersulfone and the substrate, thereby controlling the hardness of the polyethersulfone material and effectively improving the baking resistance. At the same time, the introduction of specific wear-resistant fillers can increase the hardness and improve the surface gloss. DETAILED DESCRIPTION

[0025] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several variations and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0026] The sources of experimental raw materials used in the present invention are as follows: Chloro-terminated polyethersulfone A: 7 mmol / kg chlorine end content, 19 mmol / kg hydroxyl end content, molecular weight of approximately 46,000 Da, homemade; Chloro-terminated polyethersulfone B: chlorine-terminated content of 12 mmol / kg, hydroxyl-terminated content of 14 mmol / kg, molecular weight of approximately 45,000 Da, homemade; Chloro-terminated polyethersulfone C: chlorine-terminated content of 15 mmol / kg, hydroxyl-terminated content of 11 mmol / kg, molecular weight of approximately 44,000 Da, homemade; Chloro-terminated polyethersulfone D: chlorine-terminated content of 17 mmol / kg, hydroxyl-terminated content of 9 mmol / kg, molecular weight of approximately 44,000 Da, homemade; Chloro-terminated polyethersulfone E: chlorine-terminated content of 21 mmol / kg, hydroxyl-terminated content of 5 mmol / kg, molecular weight of approximately 45,000 Da, homemade; Hydroxyl-terminated polyethersulfone A: hydroxyl-terminal content of 19 mmol / kg, chlorine-terminal content of 0 mmol / kg, molecular weight of approximately 47,000 Da, homemade; Hydroxyl-terminated polyethersulfone B: hydroxyl-terminal content of 21 mmol / kg, chlorine-terminal content of 0 mmol / kg, molecular weight of about 46000 Da, homemade; Hydroxyl-terminated polyethersulfone C: hydroxyl-terminal content of 24 mmol / kg, chlorine-terminal content of 0 mmol / kg, molecular weight of approximately 45,000 Da, homemade; Hydroxyl-terminated polyethersulfone D: hydroxyl-terminal content 26 mmol / kg, chlorine-terminal content 0 mmol / kg, molecular weight approximately 44000 Da, homemade; Hydroxyl-terminated polyethersulfone E: hydroxyl-terminal content of 28 mmol / kg, chlorine-terminal content of 0 mmol / kg, molecular weight of approximately 43,000 Da, homemade; Barium sulfate: mesh size is 4000 mesh, Huajun Chemical; Nano glass beads: mesh range is 20000 mesh, Donghai County Fucai Mineral Products Co., Ltd. Coupling agent: mercaptopropyltrimethoxysilane, Adamas; Abrasive: Zirconia beads, Shandong Hanhe New Materials Co., Ltd. N-Methylpyrrolidone: Shandong Changxin Chemical Technology Co., Ltd.; Preparation method of polyethersulfone coating of embodiment and comparative example: coupling agent, grinding agent and nano glass beads are pretreated, and then ground with chlorine-terminated polyethersulfone, hydroxyl-terminated polyethersulfone, grinding agent, organic solvent and water for 50 hours. After grinding, the zirconium beads are first filtered through a 60-mesh sieve, and then the large particles of the sample are filtered through a 150-mesh sieve to obtain the polyethersulfone coating.

[0027] Various test methods: Preparation of pencil hardness test specimen: Before spraying, polish and clean the iron plate, bake it in a 170°C oven for 10 minutes, and then cool it to room temperature before use. Use a spray gun to evenly spray the prepared coating solution onto the treated iron plate. Then bake it in a 150°C oven for 10 minutes to cure, and then bake it in a muffle furnace at 380°C for 10 minutes. By controlling the amount of coating solution sprayed, the thickness of the baked coating should be between 10 and 15 μm, which is acceptable.

[0028] Preparation of gloss sample: Use a spray gun to evenly spray the prepared coating solution on the aluminum plate, then place it in a 150℃ oven to cure for 10 minutes, and then bake it in a muffle furnace at 380℃ for 10 minutes. By controlling the spraying amount of the coating solution, the thickness of the coating after baking is 10~15 μm, which is qualified.

[0029] (1) Hardness: Pencil hardness test according to ISO 15184 standard.

[0030] (2) Baking: Place the prepared hot hardness test specimen in a 200°C oven and bake continuously for 500 hours. After baking, test the pencil hardness according to ISO 15184. Qualification standard: If the hardness does not decrease or decreases by only one level, the sample is qualified.

[0031] (2) Gloss: Measured in accordance with ISO 2813 using an incident angle of 60°.

[0032] Table 1: Content of each component and test results of polyethersulfone coatings in Examples and Comparative Examples Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Chloro-terminated polyethersulfone A B C D E E A Chloro-terminated polyethersulfone content 60 60 60 60 60 60 55 Hydroxyl-terminated polyethersulfone label E D C B A E A Hydroxyl-terminated polyethersulfone content 10 10 10 10 10 10 15 barium sulfate 30 30 30 30 30 30 45 Nano glass beads 15 15 15 15 15 15 / coupling agent 0.5 0.5 0.5 0.5 0.5 0.5 0.5 N-Methylpyrrolidone 110 110 110 110 110 110 110 water 180 180 180 180 180 180 180 hardness 3B 2B B HB HB 2B 3B Baking resistance 4B 2B B HB HB 3B 3B Glossiness 92 92 92 92 92 92 87 It can be seen from Examples 1-6 that the preferred chlorine end content and hydroxyl end content result in higher hardness and better baking resistance.

[0033] Table 1 continued: Example 8 Example 9 Example 10 Comparative Example 1 Chloro-terminated polyethersulfone A A A / Chloro-terminated polyethersulfone content 60 45 70 / Hydroxyl-terminated polyethersulfone label A A A E Hydroxyl-terminated polyethersulfone content 10 25 5 70 barium sulfate / 20 15 30 Nano glass beads 45 20 10 15 coupling agent 0.5 1 0.3 0.5 N-Methylpyrrolidone 110 100 130 110 water 180 200 160 180 hardness 3B 3B 3B 4B Baking resistance 3B 3B 3B 6B Glossiness 95 93 9 92 It can be seen from Comparative Example 1 that the hardness of the coating using pure hydroxyl-terminated polyethersulfone resin is too low and its baking resistance is poor.

Claims

1. A polyethersulfone coating, characterized in that Calculated by weight, it includes the following components: 45-85 parts of chlorine-terminated polyethersulfone; 3-25 parts of hydroxy-terminated polyethersulfone; 10-45 parts of wear-resistant filler; 0.1-2 parts of coupling agent; 80-150 parts of organic solvent; 120-220 parts of water.

2. The polyethersulfone coating according to claim 1, characterized in that The chlorine-terminated polyethersulfone has a chlorine-terminated content greater than 7 mmol / kg, preferably greater than or equal to 15 mmol / kg, and more preferably greater than or equal to 17 mmol / kg.

3. The polyethersulfone coating according to claim 1, wherein The hydroxyl end content of the hydroxyl-terminated polyethersulfone is less than 30 mmol / kg, preferably less than or equal to 24 mmol / kg, and more preferably less than or equal to 21 mmol / kg.

4. The polyethersulfone coating according to claim 1, wherein The molecular weight of the chlorine-terminated polyethersulfone is 38,000-60,000 Da; the molecular weight of the hydroxyl-terminated polyethersulfone is 38,000-60,000 Da.

5. The polyethersulfone coating according to claim 1, characterized in that The wear-resistant filler is selected from at least one of barium sulfate, nano-glass beads, silicon dioxide, aluminum oxide, silicon carbide, silicon nitride, polytetrafluoroethylene, and polyimide, and is preferably a compound of barium sulfate and nano-glass beads in a weight ratio of (5-2): (3-1).

6. The polyethersulfone coating according to claim 5, characterized in that The mesh size of the barium sulfate is in the range of 3000-5000 mesh; the mesh size of the nano glass microspheres is in the range of 20000-30000 mesh; and the nano glass microspheres are selected from at least one of hollow glass microspheres and solid glass microspheres.

7. The polyethersulfone coating according to claim 1, characterized in that The organic solvent is selected from at least one of N-methylpyrrolidone, sulfolane, N,N'-dimethylacetamide and N,N'-dimethylformamide.

8. The polyethersulfone coating according to claim 1, characterized in that The coupling agent is selected from silane coupling agents.

9. The polyethersulfone coating according to claim 1, characterized in that By weight, the invention further comprises one or more of 0-1 parts of abrasive, 0-0.5 parts of antioxidant, 0-2 parts of lubricant, 0-0.8 parts of nucleating agent and 0-3 parts of cross-linking agent.

10. The method for preparing the polyethersulfone coating according to any one of claims 1 to 9, characterized in that: The following steps are involved: The coupling agent, barium sulfate and nano glass beads are pretreated, and then ground with chlorine-terminated polyethersulfone, hydroxyl-terminated polyethersulfone, abrasive, organic solvent and water, and filtered through a filter to obtain a polyethersulfone coating.