POM plastic POM plastic
(polyoxymethylene) (Saigang~Trane)
English name: Polyoxymethylene (Polyformaldehyde)
POM (polyoxymethylene resin) definition: Polyoxymethylene is obtained by polymerizing formaldehyde. It is a high-density, high-crystallinity thermoplastic engineering plastic. It has good physical, mechanical and chemical properties, especially excellent friction resistance. It is precisely because these excellent chemical and physical properties are comparable to steel, and the weight is lighter than steel, that it is called "Sai Steel"!
Specific gravity: 1.41-1.43 g/cm3 Molding shrinkage: 1.2-3.0 Molding temperature: 170-200℃ Drying conditions: 80-90℃ 2 hours
Comprehensive performance of materials Better, with high strength and stiffness, good wear reduction and wear resistance, low water absorption, and good dimensional stability, but poor thermal stability, easy to burn, and easy to age when exposed to the atmosphere. Suitable for making wear-reducing and wear-resistant parts, transmission parts, chemical industry, instrumentation and other parts
Molding properties 1. Crystalline material, narrow melting range, fast melting and solidification, the material temperature will be slightly lower than the melting temperature. crystallization. Liquidity is medium. It absorbs little moisture and can be used without drying.
2. Low friction coefficient, good elasticity, and surface defects such as wrinkles are prone to occur on the surface of plastic parts.
3. Easily decomposes, with a decomposition temperature of 240 degrees. During decomposition, irritating and corrosive gases are produced. Therefore, mold steel should be made of corrosion-resistant materials.
PBT plastic PBT plastic
Polybutylene terephthalate, the English name is polybutylece terephthalate (referred to as PBT), PBT is a milky white translucent to opaque, crystalline thermoplastic polyester . It has high heat resistance, toughness, fatigue resistance, self-lubrication, low friction coefficient, weather resistance, and low water absorption rate of only 0.1. It still maintains various physical properties (including electrical properties) and electrical insulation in humid environments, but Volume resistance and dielectric loss are large. Resistant to hot water, alkalis, acids, and oils, but susceptible to corrosion by halogenated hydrocarbons, poor hydrolysis resistance, rapid crystallization at low temperatures, and good formability. The disadvantages are low notch impact strength and large molding shrinkage. Therefore, most of them are modified with glass fiber reinforcement or inorganic filling. Their tensile strength and bending strength can be more than doubled, and the heat distortion temperature is also greatly increased. It can work at 140℃ for a long time. The longitudinal and transverse shrinkage rates of glass fiber reinforced products are inconsistent, which can easily cause the products to warp.
PBT crystallizes quickly, and the most suitable processing method is injection molding. Other methods include extrusion, blow molding, coating and various secondary processing moldings. Pre-drying is required before molding, and the moisture content must be reduced to 0.02.
PBT (enhanced and modified PBT) is mainly used in automobiles, electronic appliances, industrial machinery, polymer alloys, and chemical mixing industries. Such as distributors, car body parts, ignition coil bobbins, insulating covers, exhaust system parts, motorcycle igniters, and electronic and electrical industries such as TV deflection coils, picture tubes and potentiometer brackets, audio output Transformer skeleton, adapter skeleton, switch connector, electric fan, refrigerator, washing machine motor end cover, bushing.
In addition, there are transportation machinery parts, sewing machine and textile machinery parts, watch casings, lens barrels, electric iron covers, mercury lampshades, baking oven parts, power tool parts, shielding covers, etc.
PPO plastic PPO plastic (MPPO)
(polyphenylene ether)
English name: poly(phenylene oxide)
Specific gravity: 1.07 g/cm3 Molding shrinkage: 0.3-0.8 Molding temperature: 260-290℃ Drying conditions: 130℃ 4 hours
Material properties 1. It is white particles. It has good overall performance and can be used in 120-degree steam. It has good electrical insulation and low water absorption, but it has a tendency of stress cracking. Modified polyphenylene ether eliminates stress cracking.
2. It has outstanding electrical insulation, excellent water resistance, and good dimensional stability. Its dielectric properties rank first among plastics.
3. MPPO is a modified material made by mixing PPO and HIPS. All the materials currently on the market are this kind of material.
4. It has high heat resistance, with a glass transition temperature of 211 degrees and a melting point of 268 degrees. It has a tendency to decompose when heated to 330 degrees. The higher the PPO content, the better the heat resistance. The heat distortion temperature Up to 190 degrees.
5. It has good flame retardancy, is self-interesting, and has moderate flammability after being mixed with HIPS. Lightweight, non-toxic and can be used in the food and pharmaceutical industries. It has poor light resistance and will change color if used in the sun for a long time.
6. It can be mixed and modified with ABS, HDPE, PPS, PA, HIPS, glass fiber, etc. 1. Suitable for making heat-resistant parts, insulation parts, wear-reducing and wear-resistant parts, transmission parts, medical and electronic parts.
2. It can be used as gears, vanes, valves and other parts used at higher temperatures, and can be used instead of stainless steel.
3. Can make screws, fasteners and connectors.
4. Electrical parts of motors, rotors, casings, and transformers.
Molding performance 1. Amorphous material, low moisture absorption.
2. It has poor fluidity, similar to Newtonian fluid, and its viscosity is sensitive to temperature. The thickness of the product is generally above 0.8 mm. Easily decomposes and produces corrosive gases when decomposed. The molding temperature should be strictly controlled, the mold should be heated, and the pouring system should have small resistance to material flow.
3. The water absorption rate of polyphenylene ether is very low, about 0.06%, but a small amount of moisture will cause silver streaks and other non-smooth phenomena on the surface of the product. It is best to dry it, and the temperature should not be higher than 150 degrees. , otherwise the color will change.
4. The molding temperature of polyphenylene ether is 280-330 degrees, and the molding temperature of modified polyphenylene ether is 260-285 degrees.
ABS plastic ABS plastic
Chemical name: Acrylonitrile-butadiene-styrene polymer
English name: Acrylonitrile Butadiene Styrene
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Specific gravity: 1.05 g/cm3 Molding shrinkage: 0.4-0.7
Molding temperature: 200-240℃ Drying conditions: 80-90℃ 2-hour working temperature: -50~ 70℃
Features:
1. Good overall performance, high impact strength, chemical stability, and good electrical properties.
2. Comparable with 372 organic glass It has good weldability and can be made into two-color plastic parts, and the surface can be chrome-plated and spray-painted.
3. It has high impact resistance, high heat resistance, flame retardant, reinforced, transparent and other grades.
4. The fluidity is slightly worse than HIPS, better than PMMA, PC, etc., and has good flexibility.
Usage: Suitable for making general mechanical parts, wear-reducing and wear-resistant parts, transmission parts and telecommunications parts.
Molding characteristics:
1. Amorphous material , medium fluidity, high moisture absorption, must be fully dried, plastic parts requiring glossy surface must be preheated and dried for a long time at 80-90 degrees, 3 hours.
2. It is advisable to choose high material temperature and high mold temperature , but the material temperature is too high and it is easy to decompose (the decomposition temperature is