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Feel free to contact us with any questions. If you have any doubt about the price, we can give a proper discount by different purchasing quantity. Basic information editing and broadcasting brief introduction Polyoxyxylene was made by General Electric A.S. Hay in 1956. It uses cuprous chloride as catalyst to make 2,6-dimethylphenol into polyoxyxylene by oxidative coupling. It was published in 1964 and named PPO. Polyoxyxylene is one of the cheap high-temperature resistant plastics, but it is difficult to manufacture, and its impact resistance and heat resistance will decrease with time. Mixing polyoxyxylene and polystyrene can improve this disadvantage. In the 1960s, the adjusted polyoxyxylene came out under the trade name of Noryl. The main products in the market are modified polyphenylene oxide (MPPO), or MPPE (modified polyphenylene ether). Basic properties of polyphenylene ether 1. It is white particle. It has good comprehensive performance, can be used in 120 ℃ steam, good electrical insulation, small water absorption, but has a tendency of stress cracking. Modified polyphenylene ether can eliminate stress cracking. 2. It has outstanding electrical insulation and water resistance, good wear resistance and electrical performance, and good dimensional stability. Its dielectric properties rank first among plastics. 3. MPPO is a modified material made by blending PPO and HIPS, and all materials on the market are of this kind. 4. It has high heat resistance, with a glass transition temperature of 211 degrees, a melting point of 268 degrees, and a decomposition tendency when heated to 330 degrees. The higher the content of PPO, the better its heat resistance, and the thermal deformation temperature of 190 degrees. 5. It has good flame retardancy, self-ignition and moderate flammability after mixing with HIPS. It is light and non-toxic and can be used in the food and drug industry. Poor light fastness. It will change color when used in the sun for a long time. 6. It can be blended with ABS, HDPE, PPS, PA, HIPS, glass fiber, etc. Characteristics of PPO plastic raw materials A. PPO plastic raw material is non-toxic, transparent, with low relative density, and has excellent mechanical strength, stress relaxation resistance, creep resistance, heat resistance, water resistance, water vapor resistance, and dimensional stability. B. Good electrical performance in a wide range of temperature and frequency variation, non-hydrolysis, low shrinkage of type [1], flame retardant and self-extinguishing, poor resistance to inorganic acids, alkalis, aromatic hydrocarbons, halogenated hydrocarbons, oils, etc., easy to swell or stress cracking. C. It has the advantages of large rigidity, high heat resistance, flame resistance, high strength and excellent electrical performance. D. The polyether also has the advantages of abrasion resistance, non-toxicity and pollution resistance. E. The dielectric constant and dielectric loss of PPO plastic raw materials are one of the smallest varieties in engineering plastics, which are almost independent of temperature and humidity, and can be used in low, medium and high frequency electric fields. F. The load deformation temperature of PPO can reach above 190 ℃, and the embrittlement temperature is - 170 ℃. G. The main disadvantages are poor melting fluidity and difficult processing and molding. physical property PPO is non-toxic, transparent, low relative density, and has excellent mechanical strength, stress relaxation resistance, creep resistance, heat resistance, water resistance, water vapor resistance, and dimensional stability. Good electrical performance in a wide temperature and frequency range. The main disadvantages are poor melting fluidity and difficult processing and molding. Most of the practical applications are MPPO (PPO blend or alloy). If PPO is modified with PS, it can greatly improve the processing performance, improve the stress cracking resistance and impact resistance, and reduce the cost, but the heat resistance and gloss are slightly reduced. Modified polymers include PS (including HIPS), PA, PTFE, PBT, PPS and various elastomers, polysiloxane, PS modified PPO has a long history and a large amount of products. MPPO is the most widely used general engineering plastic alloy. The major MPPO varieties include PPO/PS, PPO/PA/elastomer and PPO/PBT/elastomer alloy. PPO and MPPO can be processed by injection molding, extrusion, blow molding, molding, foaming and electroplating, vacuum coating, printing machine processing and other processing methods. Due to the high melt viscosity, the processing temperature is high. PPO and MPPO are mainly used in electronic appliances, automobiles, household appliances, office equipment and industrial machinery, etc. They are used to make automotive instrument panels, radiator grilles, speaker grilles, consoles, fuse boxes, relay boxes, connectors and wheel housings by taking advantage of MPPO's heat resistance, impact resistance, dimensional stability, scratch resistance, peeling resistance, coating ability and electrical properties; In the electronic and electrical industry, it is widely used to manufacture connectors, coil spools, switch relays, tuning equipment, large electronic displays, variable capacitors, battery accessories, microphones and other components. It is used for TV, camera, video tape, recorder, air conditioner, heater, rice cooker and other parts in household appliances. It can be used as external parts and components of copiers, computer systems, printers, fax machines, etc. In addition, it can be used as the shell and parts of cameras, timers, water pumps, blowers, silent gears, pipes, valve bodies, surgical instruments, disinfectors and other medical appliance parts. Large-scale blow molding can be used for large parts of automobiles, such as choke plates, bumpers, and low foaming molding. It is suitable for making large products with high rigidity, dimensional stability, excellent sound absorption, and complex internal structure, such as various machine shells, bases, and internal supports, with large design freedom and lightweight products. chemical property The chemical formula is abbreviated as PPO. Thermoplastic resin formed by oxidative coupling polymerization of 2,6-disubstituted phenol is generally in the form of earthy yellow powder. Commonly used is polyphenylene ether synthesized from 2,6-dimethylphenol, which has excellent comprehensive performance. The biggest feature is that it has excellent dimensional stability and outstanding electrical insulation under long-term load. It can be used for a long time in the range of - 127~121 ℃. It has excellent water and steam resistance, high tensile strength and impact strength, and good creep resistance. In addition, it has good wear resistance and electrical properties. It is mainly used to replace stainless steel in manufacturing surgical medical instruments. In the electromechanical industry, it can be used to make gears, blower blades, pipes, valves, screws and other fasteners and connectors. It can also be used to make components in the electronic and electrical industries, such as coil framework and printed circuit boards. In 1964, General Electric Company of the United States first realized the industrial production of polyphenylene ether using 2,6-dimethylphenol as raw material. In 1966, GE produced modified polyphenylene oxide (MPPO). In 1984, the world consumption of polyphenylene ether was 163 kt. Preparation method A preparation method of polyphenylene ether comprises the following steps: contacting the polyphenylene ether solution obtained by polymerization in the presence of an insoluble polymerization solvent and catalyst with a chelating agent aqueous solution, terminating the polymerization reaction and deactivating the catalyst; Then add a water-soluble solvent of insoluble polyphenylene ether to precipitate the polyphenylene ether, and separate and recover the precipitated polyphenylene ether; Among them, (a) the polyphenylene ether solution is mixed with the chelating agent aqueous solution and kept for 10~180 minutes at 50~120 ℃; Among them, (b) the mixture after separation and recovery of polyphenylene ether contains insoluble polymerization solvent and water-soluble insoluble solvent of polyphenylene ether, and this mixture is added to water to extract the solvent of water-soluble insoluble polyphenylene ether, so that the solvent of water-soluble insoluble polyphenylene ether is extracted into the water phase and separated from the polymerization solvent; Among them, (c) The solvent of water-soluble insoluble polyphenylene ether is separated and removed from the aqueous phase by distillation, and all or part of the water left is recycled to contact with the filtrate after separation of polyphenylene ether, and the content of high-boiling organic matter in the left aqueous phase is 1 weight% or less. Methods of industrial production It includes two parts: polymerization and post-treatment: adding a quantitative copper ammonia complex catalyst in the polymerization reactor, bubbling oxygen into the reactor, and then gradually adding 2,6-dimethylphenol and ethanol solution for oxidative coupling polymerization to obtain the polymer. After treatment, the polymer is centrifuged, washed with ethanol solution containing 30% sulfuric acid, and then soaked in dilute alkali solution, washed, dried and granulated to obtain the granular resin of polyphenylene ether. 2,6-diphenylphenol can also be used as monomer, and the obtained polyphenylene ether has better thermal stability, which has been used to manufacture high-temperature resistant films and insulating products. In order to improve the molding and processing performance and reduce the cost, polyphenylene ether can be modified by blending method. The modified polyphenylene ether has low cost and market price can compete with ABS resin. It is widely used to replace bronze or brass to make various mechanical parts and pipes. security information R36 Irritating to eyes. R37 Irritates the respiratory system. R38 Irritating to skin. [1] Editing and broadcasting of forming process l) Non-crystallized material, low moisture absorption, low water absorption of PPO, but water will cause silver wire, bubbles and other defects on the surface of the product. Therefore, the raw material can be put in an oven at 80~100C for drying for 1-2 hours before use. 2) PPO has high molecular bond rigidity, high glass transition temperature and is difficult to orient, but it is difficult to relax after forced orientation. Therefore, the residual internal stress in the product is high, and it is generally subject to post-treatment. 3) PPO is an amorphous material, and its rheological property is close to Newtonian fluid in the melting state, but the greater the degree of deviation from Newtonian fluid with the increase of temperature. 4) The viscosity of PPO melt is large, so the temperature should be increased during processing and the injection pressure should be appropriately increased to improve the filling capacity. 5) The recycled material of PPO can be reused for 3 times, and its performance is not significantly reduced. 6) The PPO melt should be molded by screw injection molding machine, and the nozzle should be a straight-through type, with a hole diameter of 3-6mm 7) During PPO injection molding, high pressure and high speed injection should be adopted, and the pressure holding and cooling time should not be too long. 8) The sprue of the mold should adopt a larger taper or a draw hook, and the sprue should be short and thick. 9) The gate should be direct, fan-shaped or flat. The diameter of needle-shaped gate should be appropriately increased. For long gate, hot runner structure can be used. 10) The molding shrinkage of PPO is small, generally 0.2% - 0.7%, so the product has excellent dimensional stability. 11) Poor fluidity, similar to Newtonian fluid, viscosity is sensitive to temperature, and product thickness is generally more than 0.8mm. It is easy to decompose and produce corrosive gas during decomposition. The molding temperature should be strictly controlled, the mold should be heated, and the resistance of the pouring system to the material flow should be small. 12) The water absorption of polyphenylene ether is very low by about 0.06%, but a small amount of water will lead to the appearance of silver and other unsmooth phenomena on the surface of the product. It is better to dry the product. The temperature should not be higher than 150 degrees, otherwise the color will change. 13) The molding temperature of polyphenylene ether is 280-330 ℃, and the molding temperature of modified polyphenylene ether is 260-285 ℃. Injection molding process melting temperature of PPO plastic raw material: 270-290 ℃ Constant temperature of material barrel: PPO has high heat resistance, thermal decomposition temperature reaches 350C, and there is no obvious thermal degradation within 300C. Generally, the barrel temperature is controlled at 260~290C, and the nozzle temperature is about lOC lower than the barrel temperature. Mold temperature: due to the high viscosity of PPO melt, higher mold temperature should be used during injection molding. Generally, the mold temperature is controlled at 100~15OC. When the mold temperature is lower than 1 OOC, thin-walled plastic parts are prone to insufficient filling and delamination; When the temperature is higher than 15OC, bubbles, silver wires, warpage and other defects are easy to appear. Injection pressure: increase the injection pressure, which is conducive to mold filling of molten material. Generally, the injection pressure is controlled at 100-14OMPao Holding pressure: 40% - 60% of injection pressure Back pressure: 3-10 MPa (30-100 bar) Injection speed: products with long flow channels need rapid injection; However, in this case, ensure that the membrane has sufficient ventilation. Screw speed: medium screw speed, equivalent linear speed is 0.6m/s Metering stroke: 0.5-3.5D Residue volume: 3-6 mm, depending on the metering stroke and screw diameter. Pre-drying: drying at 110 ℃ for 2h. Recovery rate: the material can be recycled and processed as long as the recycled material does not undergo thermal degradation. Shrinkage: 0.8% - 1.5% Gate system: use point or latent gate for small products, otherwise use straight gate or round gate; The heating system can be shut down during shutdown of hot runner machine; Under the back pressure of the bottom screw, operate several metering cycles, and empty the barrel like the extruder. Barrel equipment: standard screw, check ring, straight nozzle. Application field editing and broadcasting Pure PPO materials have the disadvantages of poor melting fluidity and high price. The products sold on the market are all improved products with excellent comprehensive performance. They are widely used in: Electronic and electrical It can meet the requirements of excellent electrical insulation under the conditions of humidity, load and high temperature. It can be used to prepare the tuning piece, coil core, microwave insulation, shielding sleeve, high-frequency printed circuit board, various high-voltage electronic components, television, computer, fax machine, copier shell, etc. automotive industry It is applicable to instrument panel, window frame, shock absorber, pump filter screen, etc. Machinery industry Used as gear, bearing, pump impeller, blower impeller, etc. Chemical industry It is used to make corrosion-resistant parts such as pipes, valves, filters and submersible pumps. The performance of PPO determines its application field and scope: 1) MPPO has small density, easy processing, thermal deformation temperature of 90~175 ℃, different specifications of goods, good dimensional stability, suitable for manufacturing office equipment, household appliances, computers and other boxes, chassis and precision parts. 2) The dielectric constant and dielectric loss tangent of MPPO are the lowest among the five general engineering plastics, that is, they have the best insulation and heat resistance, and are suitable for the electrical industry. It is suitable for manufacturing electrical insulation parts used under wet and loaded conditions, such as coil frame, tube base, control shaft, transformer shielding sleeve, relay box, insulation support, etc. 3) MPPO has good water resistance and heat resistance, and is suitable for manufacturing water meters and pumps. The bobbin used in the textile factory needs to be resistant to cooking, and the bobbin made of MPPO has a long service life. 4) The dielectric constant and dielectric loss tangent of MPPO are not affected by temperature and cycle number in engineering plastics, and have good heat resistance and dimensional stability, which are suitable for electronic industry. 5) Due to the development of the electronic industry and communication industry, mobile phones, portable computers, high-performance cameras, video cameras, etc. all need lithium-ion batteries, so the lithium-ion battery market has great prospects for development. The packaging materials of organic electrolyte for lithium-ion batteries used to be ABS or PC, and the MPPO for batteries was developed abroad in 2013, with its performance superior to the former two. 6) MPPO has a wide range of applications in the automotive industry, such as instrument dials, protective bars, etc. PPO and PA alloys, especially the specifications and varieties with high impact resistance, are used for external components, which are developing rapidly. 7) In chemical industry, modified polyphenylene ether can be used to manufacture corrosion-resistant equipment. Its hydrolysis resistance is particularly good, and it is also resistant to acid, alkali and soluble in aromatic hydrocarbons and chlorinated hydrocarbons. 8) For medical devices, it can replace stainless steel and other metals in hot water storage tank and exhaust fan mixed packing valve. |