Five types of high temperature resistant engineering plastics "Practical collection of plastic industry personnel"
PPO (polyphenylene oxide) is an amber transparent material with a specific gravity close to water of 1.06.
1. Combustion characteristics: It is difficult to burn, and it is extinguished after being fired. The flame is thick black smoke, and the fruit is stinky when the plastic melts.
2, the biggest advantage: the highest glass transition temperature of thermoplastic plastics 210 ° C, therefore, its high temperature resistance is very high;
PPO has the ability to boil water at high temperature without deformation or decomposition. PPO is hard and tough and has high creep resistance. Its surface hardness is higher than PAPOMPC, creep is lower than these three materials; it has good elongation at -135 °C at lower temperature; dimensional stability. PPO can be metallized, that is, it can be electro-optic or vacuum-coated; PPO has excellent dielectric properties and can be kept constant over a wide range of frequencies, temperatures, and humidity.
3. Disadvantages: PPO will cause stress cracking in the case of organic solvents; PPO is not weather resistant and is susceptible to discoloration under the illumination of sunlight. PPO has poor fluidity and is difficult to process
4. Uses: Due to the above advantages, PPO is most suitable for applications where wet and loaded, ie, requires excellent dielectric properties, high mechanical properties, and dimensional stability: such as tuning sheets, Microwave insulation, etc. Water treatment equipment, water distillation equipment, pump parts, retort equipment, such as: medical equipment, food materials, high rigidity, high-strength electrical enclosures and other parts, it is a more advanced shell material than PC
5, injection molding performance: PPO is a crystalline plastic, has a clear melting point, melting at 217 ° C, but its viscosity is large, difficult to flow effectively, decomposition at 360 ° C; general processing temperature is 280 ° C - 340 ° C; PPO Water absorption, in the case of moisture, can cause decomposition, need to be dried, can be dried at 140 ° C for 2-4 hours.
In addition, NORYL is a modified product of PPO. Compared with PPO, its mechanical properties are much lower, but it can also be replaced with PC.
PPS: (Polyphenylene sulfide polyphenylenesulfide) is a white material with high crystallinity, hard and brittle, excellent thermal stability, and can be characterized by high resistance of thermosetting plastics. Pure PPS can't be injection molded because it is too viscous and not easy to flow. The PPS for injection molding has been modified, and many fillers and modifiers have been added, which means that the PPS for injection molding is modified PPS.
1. Combustion characteristics: non-combustible, extinguished after leaving the fire. But when they beat each other, they made a metal-like "jingle" sound.
2, the biggest advantage: at higher temperatures, can resist any solvent corrosion; PPS anti-creep performance is high, other mechanical properties are also relatively high; PPS can maintain its mechanical properties and size at high temperatures; PPS Excellent electrical properties, constant at a wide frequency, temperature and humidity.
3. Disadvantages: PPS has poor fluidity and is difficult to process
4. Use: Due to the above advantages, PPS is most suitable for heat insulation, anti-corrosion and insulation materials under high temperature and humidity and under load.
5, injection molding performance: PPS is a crystalline plastic, has a clear melting point, melting at 280 ° C, but its viscosity is large, difficult to flow effectively, decomposition at 400 ° C; general processing temperature is 300 ° C - 340 ° C; PPO Water absorption, in the case of moisture, can cause decomposition, need to be dried, can be dried at 140 ° C for 2-4 hours
PSF: It is a microstrip amber transparent material (some PSF is ivory opaque material) with a medium specific gravity of 1.24.
1. Combustion characteristics: It is non-flammable, extinguished after being fired, and the flame is yellow-brown smoke. The plastic burns and melts while emitting the burnt smell of rubber.
2, the biggest advantage: has outstanding high temperature and low temperature resistance; at 150 ° C, it can still maintain its mechanical strength of 80%, at -100 ° C, it can maintain its mechanical strength of 75%; PSF has Outstanding creep resistance, which keeps its various mechanical strengths lasting; PSF has outstanding high-temperature dielectric properties, maintaining dielectric properties in water at 190 ° C in water and in moisture; PSF has outstanding Radiation resistance; PSF can be metallized, ie can be electro- or vacuum coated
3. Disadvantages: PSF does not hydrolyze, but under high temperature and load, water will cause stress cracking; PSF has poor fluidity and is difficult to process.
4. Use: Due to the above advantages, PSF is most suitable for manufacturing electrical and electronic components with precision tolerance, rigidity, thermal stability and good electrical insulation properties. PSF is most suitable for manufacturing parts that require thermal properties, chemical resistance, durability, and rigidity. PSF is not easily hydrolyzed at low temperatures, and can also be used to make parts for low temperature water treatment equipment, water pump parts, water valves, washing machine parts, It is a high-rigidity housing material that is more advanced than PC;
5, injection molding performance: PSF injection temperature is high 280-320, modified PSF and PC injection molding conditions are similar; baking temperature is similar to PC.
Polyarylate: Polyarylate is a transparent material.
1. Combustion characteristics: flammable, self-extinguishing after leaving the fire. A small amount of non-toxic fumes can be produced when burning. The representative brand is: U-100
2, the biggest advantage: polyaryl ester without glass fiber reinforced, it has excellent heat resistance; polyaryl ester can be self-extinguishing without adding flame retardant, producing yield smoke when burning, but non-toxic, in line with safety specifications. The polyarylate has a small thermal expansion coefficient, a small creep variable, and a small hygroscopicity, and the polyarylate is resistant to acids and oils.
3. Disadvantages: polyester is not resistant to alkali and organic solvents
4, use: due to the above advantages, polyaryl ester is most suitable for household appliances
5, injection molding performance: Polyaryl ester must be dried before processing, drying conditions are 100 ° C -120 ° C temperature, drying 4-6 hours, injection molding temperature is 330 ° C -350 ° C
1. Combustion characteristics: Polyarylsulfone is a transparent material, and polyarylsulfone is slightly heavier than polysulfone. Its representative is: Astrel360
2, the biggest advantage: the heat resistance is much higher, the heat distortion temperature and continuous use is about 100 ° C higher than the PSF. The mechanical strength of polyarylsulfone is similar to that of polysulfone.
3. Disadvantages: Polyarylsulfone has poor fluidity and is difficult to process.
4. Use: Due to the above advantages, it is used as an ultra-high temperature resistant material.
5, injection molding performance: polyaryl sulfone processing temperature is 320 ° C - 410 ° C; mold temperature 232 ° C -260 ° C; it has greater hygroscopicity, water absorption, must be dried before processing, drying conditions: 260 ° C drying 2-4 hours.