It is necessary to collect a complete collection of 21 commonly used properties of plastic!

It is necessary to collect a complete collection of 21 commonly used properties of plastic!
1. ABS plastic (acrylonitrile butadiene styrene) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: Acrylonitrile Butadiene Styrene

Specific gravity: 1.05 g/cm3

Shaping shrinkage: 0.4-0.7%

Forming temperature: 200-240℃

Drying conditions: 80-90℃ for 2 hours

Material properties

1. Good overall performance, high impact strength, chemical stability and good electrical properties.

2.Good alloy with 372 plexiglass, made of two-tone plastic parts, chrome and paintable.

3. There are grades with high impact resistance, high temperature resistance, flame retardant, reinforced, transparent and other grades.

4. The flow is slightly worse than HIPS, better than PMMA, PC, etc., and has good flexibility.

Suitable for making general mechanical parts, anti-friction and wear-resistant parts, transmission parts and telecommunications parts.

Formability

1. Amorphous materials have medium fluidity and high moisture absorption, so they must be completely dried. Plastic parts that require a glossy surface must be preheated and dried at a temperature of 80-90 degrees for 3 hours.

2. It is desirable to use high material temperature and high mold temperature, but if material temperature is too high, it is easy to decompose (decomposition temperature > 270 degrees). -80 degrees.

3. If you need to eliminate watermark, you need to improve fluidity of material, accept high temperature of material, high temperature of mold, or change water level and other methods.

4. If heat-resistant or fire-resistant materials are molded, plastic degradation products remain on mold surface after 3-7 days of production, resulting in a glossy mold surface. be cleaned in time, and exhaust position must be added on mold surface.

2. PP plastic (polypropylene) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: Polypropylene

Specific gravity: 0.9–0.91 g/cm3

Shaping shrinkage: 1.0-2.5%

Forming temperature: 160-220℃

Drying conditions: ---

Material properties

The low density, strength, stiffness, hardness and heat resistance are better than HDPE, and it can be used at about 100 degrees. it becomes brittle at low temperatures and is not resistant to heat. Mold ages easily.

Suitable for making general mechanical parts, corrosion resistant parts and insulating parts.

Formability

1. Crystalline material, low hygroscopicity, prone to melt breakdown, and easy to decompose when in contact with hot metal for a long time.

2. The fluidity is good, but shrinkage range and shrinkage amount are large, and shrinkage, dents, and deformation are possible.

3. The cooling rate is fast, filling system and cooling system must dissipate heat slowly, and pay attention to molding temperature control. The directionality is evident when temperature of material is low. This is especially evident at low temperatures. and high pressure. When mold temperature is lower than 50 degrees, plastic parts are not smooth. It is easy to produce poor welding, leaving marks, and warpage deformation easily occurs above 90 degrees.

4. The thickness of plastic wall must be the same to avoid lack of adhesive and sharp corners to prevent stress concentration.

3. PE plastic (polyethylene) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polyethylene

Specific gravity: 0.94–0.96 g/cm3

Shaping shrinkage: 1.5-3.6%

Forming temperature: 140-220℃

Drying conditions: ---

Material properties

Excellent corrosion resistance, electrical insulation (especially high-frequency insulation), amenable to chlorination, irradiation and modification, can be reinforced with glass fiber. LDPE has a high melting point, rigidity, hardness and strength, and low water absorption., has good electrical properties and radiation resistance; high pressure polyethylene has good softness, elongation, toughness and permeability; Ultra high molecular weight polyethylene has high impact strength, fatigue resistance and wear resistance.

LDPE is suitable for corrosion-resistant parts and insulating parts; high-density polyethylene is suitable for making films, etc.; UHMW polyethylene is suitable for making impact-absorbing, wear-resistant and transmission materials. parts.

Formability

1. Crystallization material, low moisture absorption, no need to completely dry, excellent fluidity, fluidity is sensitive to pressure, high pressure injection is suitable for molding, material temperature is uniform, filling rate is fast, pressure is sufficient. Direct lock is not suitable. To avoid uneven shrinkage and increase in internal stresses. Pay attention to choice of position of shutter to prevent shrinkage and deformation.

2. The shrinkage range and shrinkage value are large, directionality is obvious, and it is easy to deform and deform. The cooling rate should be low, and mold should be equipped with cold material holes and a cooling system.

3. The heating time should not be too long, otherwise it will decompose and burn.

4. If soft plastic parts have shallow lateral grooves, they can be forced out of mold.

5. Melt rupture may occur, so it should not be in contact with organic solvents to prevent cracking.

4. PS plastic (polystyrene) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polystyrene

Specific gravity: 1.05 g/cm3

Shaping shrinkage: 0.6-0.8%

Forming temperature: 170-250℃

Drying conditions: ---

Material properties

Excellent electrical insulation (especially high-frequency insulation), colorless and transparent, light transmission second only to organic glass, colorability, water resistance, good chemical resistance, medium strength, but brittle, prone to brittle stress cracking, not resistant to benzene, gasoline and other organic solvents.

Suitable for making insulating transparent parts, decorative parts, chemical instruments, optical instruments and other parts.

Formability

1. The amorphous material has low moisture absorption, does not need to be completely dried, does not decompose well, but has a large coefficient of thermal expansion and is subject to internal stresses, has good fluidity, and can be molded with a screw or plunger injection molding machine.

2. It is advisable to use high material temperature, high mold temperature, low injection pressure, and increasing injection time is beneficial to reduce internal stress and prevent shrinkage cavity and deformation.

3. Various gate shapes can be used, and gate is connected by an arc of plastic parts to avoid damage to plastic parts when gate is removed. The demoulding slope is large and ejection is uniform. Inserts, if any, must be preheated.

5. Plastic PMMA (plexiglass) (polymethyl methacrylate) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polymethyl methacrylate

Specific gravity: 1.18 g/cm3

Shaping shrinkage: 0.5-0.7%

Forming temperature: 160-230℃

Drying conditions: 70-90℃ for 4 hours

Material properties

Excellent transparency, high strength, certain heat and cold resistance, corrosion resistance, good insulation, comprehensive performance, superior to polystyrene, but brittle, easy to melt in organic solvents such as light-transmitting materials. Its surface hardness is slightly lower and it is easy to scratch.

Suitable for making transparent insulating parts and parts of medium strength.

Formability

1. Amorphous materials have high moisture absorption, need drying, do not decompose well, have medium fluidity, and are prone to poor filling, mold sticking, shrinkage, and welding marks.

2. It is suitable for high pressure injection. In absence of defects, high material temperature and high mold temperature are used to increase fluidity, reduce internal stress, improve transparency and strength. High degree, uniform emission. at same time, an exhaust port is installed to prevent foaming.

6. POM plastic (polyoxymethylene) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polyoxymethylene (polyformaldehyde)

Specific gravity: 1.41–1.43 g/cm3

Shaping shrinkage: 1.2-3.0%

Forming temperature: 170-200℃

Drying conditions: 80-90℃ for 2 hours

Material properties

Good overall performance, high strength, high rigidity, good wear resistance, low water absorption, good dimensional stability, but poor thermal stability, easy to burn and sun aging.

Suitable for manufacture of anti-friction and wear-resistant parts, transmission parts, chemical industry, instrumentation and other parts.

Formability

1. The crystallization material has a narrow melting range, fast melting and solidification, and crystallization occurs when temperature of material is slightly lower than melting point. Average mobility. Hygroscopicity is low, without drying treatment.

2. The coefficient of friction is low, elasticity is good, and surface of plastic part is prone to surface defects such as wrinkles.

3. Easy to decompose, decomposition temperature is 240 degrees. Decomposition produces irritating and corrosive gases. Therefore, mold steel must be made from corrosion resistant materials.

7. Polyvinyl chloride PVC It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: Poly(Vinyl Chloride)

Specific gravity: 1.38 g/cm3

Shaping shrinkage: 0.6-1.5%

Forming temperature: 160-190℃

Drying conditions: ---

Material properties

Excellent mechanical and electrical properties, high resistance to acids and alkalis, good chemical stability, but low softening point.

Suitable for making thin plates, wire and cable insulation layers, seals, etc.

Formability

1. Amorphous materials have low moisture absorption and poor fluidity. To improve flow and prevent formation of air bubbles, plastic can be pre-dried. The sprue system of mold should be thick and short, cross section of sprue should be large, and there should be no dead corner. The mold should be cooled, surface is chrome plated.

2. Very easy to decompose. Decompose more easily when in contact with steel and copper at a temperature of 200 degrees.

3. When using nozzle of a screw injection molding machine, hole should be large to prevent stagnation of material in dead-end corners. It is better not to have inserts. If there are inserts, they should be preheated.

8. PA plastic (nylon) (polyamide) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: Polyamide

Specific Gravity: PA6-1.14g/cc PA66-1.15g/cc PA1010-1.05g/cc

Shaping shrinkage: PA6-0.8-2.5% PA66-1.5-2.2%

Forming temperature: 220-300℃

Drying conditions: 100-110℃ for 12 hours

Material properties

Durable, wear-resistant, oil-resistant, water-resistant, anti-ferment bacteria, but with high water absorption. Nylon 6 has good elasticity, high impact strength and high water absorption. Nylon 66 is superior to nylon 6 in performance, high strength and good abrasion resistance. Nylon 66 is similar but has less water absorption and low stiffness. Nylon 1010 is translucent, has less water absorption and has better frost resistance.

Suitable for making general mechanical parts, anti-friction and wear-resistant parts, transmission parts, chemical, electrical, instrument and other parts.

Formability

1. The crystalline material with higher melting point and narrow melting point range, poor thermal stability decomposes when material temperature exceeds 300 degrees and residence time exceeds 30 minutes. Easily absorbs moisture and needs drying, water content should not exceed 0.3%.

2. Good fluidity, easy to overflow. Self-locking nozzles should be used and should be heated.

3. The molding shrinkage range and shrinkage rate are large, directionality is obvious, and shrinkage cavity and deformation tend to occur.

4. The mold temperature is selected according to wall thickness of plastic part in range of 20-90 degrees. The injection pressure is selected according to type of injection molding machine, material temperature, plastic shape and size. mold part and system. The molding cycle is selected according to wall thickness of plastic part. Of course. If resin viscosity is low, injection and cooling time should be longer, and vaseline oil should be used as a release agent.

5. The shape and size of mold gate system, increasing size of the runner and gate can reduce shrinkage.

9. PC plastic (polycarbonate) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polycarbonate

Specific gravity: 1.18–1.20 g/cm3

Shaping shrinkage: 0.5-0.8%

Forming temperature: 230-320℃

Drying conditions: 110-120℃ for 8 hours

Material properties

High impact strength, good dimensional stability, colorless and transparent, good colorability, electrical insulation, corrosion resistance, wear resistance, but poor self-lubrication, stress cracking tendency, high temperature and easy hydrolysis, and other resins. Bad compatibility.

Suitable for making insulating transparent parts and impact-resistant parts of small tool parts.

Formability

1. Amorphous material, good thermal stability, wide molding temperature range, poor fluidity. Low moisture absorption, but sensitive to water, requires drying. The casting shrinkage rate is small, and melt cracking and stress concentration are possible, so casting conditions must be strictly controlled, and plastic parts must be annealed.

2. For plastic parts with a high melting point and high viscosity over 200 g, it is recommended to use a heated extension nozzle.

3.The cooling rate is high.The frontal system of mold should be thick and short.It is desirable to install a cold well, sprue should be large, and mold should be heated.

4. If temperature of material is too low, it will lead to a shortage of material and plastic parts will be dull. If temperature of material is too high, it will easily overflow and plastic parts will bubble. When mold temperature is low, shrinkage rate, elongation rate, and toughness are high, but bending resistance, compression resistance, and tensile strength are low. When temperature of mold exceeds 120 degrees, cooling of plastic part is slow, it is easy to deform and stick to mold.

10. PFO plastic (MPPO) (polyphenylene ether) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: poly(phenylene oxide)

Specific gravity: 1.07 g/cm3

Shaping shrinkage: 0.3-0.8%

Forming temperature: 260-290℃

Drying conditions: 130℃ for 4 hours

Plastic properties

1. These are white particles. Good overall performance, can be used in pairs at 120 degrees, good electrical insulation, little water absorption, but tends to stress cracking. Modified polyphenylene ether eliminates stress cracking.

2. It has excellent electrical insulation, excellent water resistance and good dimensional stability. Its dielectric properties rank first among plastics.

3. MPPO is a modified material obtained by mixing PPO and HIPS. Currently, all materials of this type are on market.

4. It has high temperature resistance, glass transition temperature 211 degrees, melting point 268 degrees, prone to decomposition when heated up to 330 degrees. The higher PPO content, better heat resistance, and thermal distortion temperature can reach 190 degrees.

5. Good fire resistance, self-absorption and moderate flammability when mixed with HIPS. Lightweight, non-toxic and can be used in food and pharmaceutical industries. Poor lightfastness, changes color with prolonged use in sun.

6. It can be mixed and modified with ABS, HDPE, PPS, PA, HIPS, fiberglass, etc.

Target

1. It is suitable for making heat-resistant parts, insulating parts, wear-resistant and wear-resistant parts, transmission parts, medical and electronic parts.

2. It can be used as gears, fan blades, valves and other parts used at higher temperatures, and can replace stainless steel.

3. Can make screws, fasteners and connectors.

4. Electrical parts of motors, rotors, housings and transformers.

Formability

1. Non-crystalline material with low moisture absorption.

2. Poor fluidity, similar to Newtonian fluid, viscosity is temperature sensitive, and product thickness is usually greater than 0.8mm. It decomposes easily and releases corrosive gas when decomposed. The molding temperature must be strictly controlled, mold must be heated, and gate system must have little 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 threads and other roughness on surface of product. It is best to dry it, and temperature should not be higher than 150 degrees, otherwise color will fade .

4. The molding temperature of polyphenylene ether is 280-330 degrees, and molding temperature of modified polyphenylene ether is 260-285 degrees.

11. BP plastic (polysulfone) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polysulfone

Specific gravity: 1.25–1.35 g/cm3

Shaping shrinkage: 0.5-0.7%

Forming temperature: 290-350℃

Drying conditions: 130-150℃ for 4 hours

Material properties

1. Polysulfone is a transparent amber color solid material with high hardness and toughness, non-toxic, with good heat and cold resistance and aging resistance, and can be used for a long time at -100 to 175 degrees. It is resistant to corrosion of inorganic acids, alkalis and salts, but not resistant to aromatic hydrocarbons and halogenated hydrocarbons. Polyarylsulfone has high hardness, radiation resistance, good heat resistance and frost resistance, self-absorbing, can be used for a long time at a temperature of -100-175 degrees.

2. The wear resistance of material can be greatly improved by a glass fiber reinforced modification.

3. Polysulfone can be made into modified polysulfone products with ABS, polyimide, polyetheretherketone and fluoroplastics, mainly to improve its toughness and elongation, solvent and environmental resistance, processability and electroplating. For example, PSF/PBT, PSF/ABS, PSF+mineral powder.

Target

1. It is suitable for making heat-resistant parts, insulating parts, wear-reducing and wear-resistant parts, instrument parts and medical equipment parts. Polyarylsulfone is suitable for making low-temperature working parts.

2. Polysulfone is often used in manufacture of integrated circuits, coil packages, contactors, sleeve packages, capacitor films, and high-performance alkaline battery packages in electronics and electrical industries

3. Polysulfone is used in microwave oven equipment, coffee heaters, humidifiers, hair dryers, laundry steamers, beverage and food dispensers, etc. in household appliances. It can also replace non-ferrous metals for precision structural parts such as watches, copiers and cameras.

4. Polysulfone has passed relevant medical and food specifications in US and can replace stainless steel products. With characteristics of polysulfone steam resistance, hydrolysis, non-toxicity, high temperature steam sterilization, high transparency and good dimensional stability, it can be used as surgical instruments, nebulizers, fluid regulators, heart valves, pacemakers, gas masks. , braces, etc.

Formability

1. Amorphous material with high moisture absorption, water absorption rate of 0.2-0.4%, must be completely dry before use and prevent re-absorption of moisture. Keep water content below 0.1%.

2. The forming characteristics are similar to those of PC, but thermalThe ical stability is poor and it starts to decompose at 360 degrees.

3. Poor fluidity, fast cooling, suitable for molding at high temperature and high pressure. The mold should have sufficient strength and rigidity, good cold setting, short runner, and sprue size should be 1/2-1/3 of wall thickness of plastic part.

4. In order to reduce internal stress of products obtained by injection molding, temperature of mold should be controlled at level of 100-140 degrees. After molding, annealing can be carried out: annealing in a glycerine bath, 160 degrees, 1-5 minutes or in an air bath, 160 degrees, 1-4 hours. The annealing time depends on size and wall thickness of product. 5. Polysulfone is close to a Newtonian body in molten state, similar to polycarbonate, and its fluidity is temperature sensitive: in range of 310 to 420 degrees, fluidity doubles for every 30 degrees of temperature increase. Therefore, processing fluidity is mainly improved by increasing temperature during molding.

12. Plastic PTFE (F4) (polytetrafluoroethylene) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polytetrafluoroethylene

Specific gravity: 2.1-2.2 grams per cubic centimeter

Shaping shrinkage: 3.1-7.7%

Forming temperature: 330-380℃

Drying conditions: ---

Material properties

1. Long-term use temperature -200--260 degrees, excellent chemical corrosion resistance, corrosion resistance to all chemicals, lowest coefficient of friction among plastics, and good electrical properties, its electrical insulation. It is temperature independent and is known as "King of Plastics".

2. Transparent or translucent. The higher crystallinity, worse transparency. The raw materials are mainly powdered resins or concentrated dispersions, which are thermoplastic polymers with an extremely high molecular weight and a high degree of crystallinity.

Target

It is suitable for making corrosion-resistant parts, wear-reducing and wear-resistant parts, sealing parts, insulation parts and medical equipment parts.

Formability

1. Crystallized material with low moisture absorption.

2. Poor fluidity, decomposes easily and forms a corrosive gas when decomposed. The molding temperature must be strictly controlled, mold must be heated, and gate system must have little resistance to material flow.

3. Powdered resins are often formed by powder metallurgy and sintered. The sintering temperature is 360-380 degrees and should not exceed 475 degrees. Emulsion resin is usually processed by cold extrusion and sintering, which can form an anti-corrosion layer on surface of product. If clarity and strength of product is required, rapid cooling should be used. You can also use extrusion molding, as well as extrude pipes, rods and profiles.

4. The melt viscosity of PTFE is very high, and bulk viscosity decreases with increasing shear stress, showing characteristics of its non-Newtonian fluid.

5. Secondary processing, which can be thermally compressed, welded, glued, reinforced, machined, etc. to produce the final product.

13. Plastic ASA (acrylic-styrene-acrylonitrile) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: Acrylonitrile Styrene Acrylate Copolymer

Specific gravity: 1.05 g/cm3

Shaping shrinkage: 0.4-0.7%

Forming temperature: 170-230℃

Drying conditions: 80-90℃ for 2 hours

Material properties

ASA polymers are amorphous materials that can be processed by extrusion and injection molding into products that are extremely weather resistant. The mechanical properties of ASA terpolymer are generally similar to those of ABS resin, difference being that ASA's performance is much less affected by outdoor climate than ABS resin.

Target

Suitable for production of general construction fields, street furniture and car exterior mirror housings.

Formability

1. Amorphous materials have medium fluidity and high moisture absorption, so they must be completely dried. Plastic parts that require a glossy surface must be preheated and dried at a temperature of 80-90 degrees for 3 hours.

2. It is desirable to use high material temperature and high mold temperature, but if material temperature is too high (decomposition temperature>250 degrees), it is easy to decompose. For high precision plastic parts, mold temperature should be 50-60 degrees. For heat-resistant plastic parts, mold temperature should be 60-80 degrees.

3. The ASA base resin grades sold on market are as follows: Luran S grade (BASF Plastic Materials), Gelog grade (General Plastics), Centrex grade (Monsanto).

14. PPS plastic (polyphenylene sulfide) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: phenylene sulfide

Specific gravity: 1.36 g/cm3

Shape shrinkage: 0.7%

Forming temperature: 300-330℃

Drying conditions: ---

Material properties

1. Excellent electrical insulation (especially high frequency insulation), white hard and brittle, metallic sound when falling to ground, light transmission second only to organic glass, coloring, water resistance and good chemical resistance. It has excellent fire resistance and is a non-flammable plastic.

2. The strength is medium, hardness is very good, but quality is brittle, prone to brittle stress cracking, not resistant to benzene, gasoline and other organic solvents. The long-term use temperature can reach 260 degrees, and remains stable under 400 degrees of air or nitrogen. After modification by adding glass fiber or other reinforcing materials, impact strength, heat resistance and other mechanical properties can be significantly improved, density can be increased to 1.6-1.9, and molding shrinkage is only 0.15-0.25%. .

Target

Suitable for making heat-resistant parts, insulating parts, chemical instruments, optical instruments and other parts.

Formability

1. Amorphous material has little moisture absorption, but it should form after drying.

2. Fluidity is between ABS and PC. It hardens quickly, shrinks little and decomposes easily. Higher injection pressure and injection speed selected. The mold temperature is 100-150 degrees. The cone of main channel should be large and flow channel should be short.

15. ETFE plastic (polytetrafluoroethylene-ethylene copolymer) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polytetrafluoroethylene

Specific gravity: 1.7 g/cm3

Shaping shrinkage: 3.1-7.7%

Forming temperature: 300-330℃

Drying conditions: ---

Material properties

1. Long-term use temperature -80--220 degrees, excellent chemical corrosion resistance, corrosion resistance to all chemicals, lowest coefficient of friction among plastics, and good electrical properties, its electrical insulation. It is independent of temperature and is known as "King of Plastics".

2. Its chemical resistance is similar to PTFE and better than vinylidene fluoride.

3. Its creep resistance and compressive strength are better than PTFE, its tensile strength is high, and its elongation can reach 100-300%. Good dielectric properties and excellent radiation resistance.

Target

1. It is suitable for making corrosion-resistant parts, wear-reducing and wear-resistant parts, sealing parts, insulation parts and medical equipment parts.

2. Wires, cable insulation, anti-corrosion equipment, sealing materials, pump valve bushings and chemical containers.

Formability

1. Crystallized material with low moisture absorption. It can be processed into products by conventional thermoplastic processing methods.

2. Poor fluidity, decomposes easily and forms a corrosive gas when decomposed. The molding temperature should be strictly controlled and not exceed 350 degrees, mold should be heated to 100-150 degrees, and material flow resistance of casting system should be small. Thin-walled simple products with a thickness of 0.7-0.8 mm can be molded from it.

3. Transparent granules, injection molding, injection molding. The molding temperature is 300-330 degrees, and above 350 degrees may cause discoloration or blistering. It is suitable for high-speed molding and low-pressure molding, and it will be difficult to demould.

16. PFA plastic (soluble polytetrafluoroethylene) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: polytetrafluoroethylene

Specific Gravity: 2.13-2.167 g/cc

Shaping shrinkage: 3.1-7.7%

Forming temperature: 350-400℃

Drying conditions: ---

Material properties

1. It is a copolymer of a small amount of perfluoropropylperfluorovinyl ether and polytetrafluoroethylene. Melt adhesion is increased, melt viscosity is reduced and performance remains unchanged compared to PTFE. This kind of resin can be directly processed into products by conventional thermoplastic casting methods.

2. Long-term use temperature -80--260 degrees, excellent chemical corrosion resistance, corrosion resistance to all chemicals, lowest coefficient of friction among plastics, and good electrical properties, its electrical insulation. It is temperature independent and is known as "King of Plastics". Its chemical resistance is similar to that of PTFE and is superior to that of vinylidene fluoride.

3. Its creep resistance and compressive strength are better than PTFE, its tensile strength is high, and its elongation can reach 100-300%. Good dielectric properties and excellent radiation resistance. Fire resistance up to V0.

Target

1. It is suitable for making corrosion-resistant parts, wear-reducing and wear-resistant parts, sealing parts, insulation parts and medical equipment parts.

2. High temperature wires, cable insulation, anti-corrosion equipment, sealing materials, pump valve bushings, chemical containers.

Formability

1. Crystallized material with low moisture absorption. It can be processed into products by conventional thermoplastic processing methods.

2. Poor fluidity, decomposes easily and forms a corrosive gas when decomposed. The molding temperature should be strictly controlled and not exceed 475 degrees, mold should be heated to 150-200 degrees, and material flow resistance of casting system should be small.

3. Translucent granules, injection molding, injection molding. The molding temperature is 350-400 degrees, above 475 degrees it is easy to cause discoloration or blistering. And keep in mind that disbanding will be more difficult.

4. Since molten material has a corrosive effect on metal, mold must be electroplated with chromium for long-term production.

17. STEAM plastic (U-plastic) (polyarylate) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

Specific gravity: 1.2-1.26 grams per cubic centimeter

Shape shrinkage: 0.8%

Forming temperature: 300-350℃

Drying conditions: 100~120℃ - 5 hours

Material properties

1. It is a transparent amorphous thermoplastic engineering plastic with excellent heat resistance, fire resistance and non-toxicity. It can be directly processed into products by conventional thermoplastic injection molding methods.

2.It has excellent thermal properties.Under a load of 1.86Mpa, its thermal deformation temperature reaches 175 degrees, and decomposition temperature is 443 degrees. Its various mechanical properties are less affected by temperature.

Target

1. It is suitable for making electrical parts with heat resistance, fire resistance and high dimensional stability. Connectors, spools, relay cases.

2. Lighting details. It can be used to make transparent lampshades, lighting fixtures, car reflectors, etc.

Formability

1. As wall thickness of product increases, mold shrinkage increases.

2. The hygroscopicity is small, about 0.1-0.3%, but a small amount of water will cause polyarylate to decompose during injection molding. Therefore, before sculpting, the material must be dried. Make its moisture content less than 0.02%.

18. Bakelite It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: phenol-formaldehyde (PF)

Specific gravity: 1.5–2.0 g/cm3

Shaping shrinkage: 0.5-1.0%

Forming temperature: 150-170℃

Material properties

Bakelite is a hard and brittle thermosetting plastic commonly known as Bakelite. High mechanical strength, strength and wear resistance, dimensional stability, corrosion resistance, excellent electrical insulation performance.

Suitable for manufacture of insulating components of mechanisms of electrical appliances and appliances, can be used in hot and humid conditions.

Formability

1. Moldability is good, but shrinkage and directionality tend to be greater than aminoplast, and it contains moisture volatiles. It must be preheated before molding, and exhaust must be exhausted during molding process. If there is no preheating, mold temperature and molding pressure should be increased.

2. The temperature of mold has a great influence on fluidity. Generally, when it exceeds 160 degrees, the fluidity drops rapidly.

3. The cure rate is generally slower than that of aminoplastics, and a large amount of heat is generated during curing. The internal temperature of large, thick-walled plastic parts may be too high, resulting in uneven hardening and overheating.

19. Aminoplasty It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: MF, UF

Specific gravity: 1.5 g/cm3

Shaping shrinkage: 0.6-1.0%

Forming temperature: 160-180℃ Material properties

Good arc resistance and electrical insulation, good water resistance and heat resistance, suitable for compression molding, suitable for making arc-resistant electrical parts and explosion-proof electrical insulation

Formability

1. It has good fluidity and high curing speed, so preheating and molding temperature must be appropriate, and speed of coating, mold clamping and sealing must be fast.

2. The shrinkage rate during casting is high.

3. It contains a lot of moisture and volatile matter, easily absorbs moisture and agglomerates. During molding, it should be preheated and dried to prevent re-absorption of moisture, but if it is too dry, fluidity will decrease. During molding, moisture and decomposition products are present, and acidity is present. The mold must be chrome-plated to prevent corrosion, and molding exhaust must be vented.

4. The molding temperature has a great influence on quality of plastic parts. If temperature is too high, it will easily cause decomposition, discoloration and uneven bubble color.

5. The material is small, specific volume is large, material is filled with a large amount of air. generally not suitable for use.

20. Epoxy resin (EP) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: epoxy resin

Specific gravity: 1.9 g/cm3

Mold shrinkage: 0.5%

Forming temperature: 140-170℃

Material properties

Good mechanical properties, electrical insulation, chemical stability and strong adhesion to many materials, but properties are affected by type and content of fillers. Alicyclic cluster epoxy plastics have high heat resistance. Suitable for injection molding and low pressure extrusion.

It is suitable for sealing and fixing electrical, electronic components and coils, and can also be used for repairs.

Formability

1. Casting. Good flowability, slight shrinkage on cure, but poor thermal stiffness, difficult to demould.

2. The cure rate is fast and generally no exhaust is required during curing and pressure should be increased immediately after loading.

21. Silicone plastic (IS) It is necessary to collect a complete collection of 21 commonly used properties of plastic!

English name: Silicone

Specific gravity: 1.75-1.95 grams per cubic centimeter

Mold shrinkage: 0.5%

Forming temperature: 160-180℃ Material properties

High and low temperature resistance, good water resistance, good high frequency insulation, good radiation resistance, good ozone resistance, suitable for making electrical, electronic components, sealing and fixing coils.

Formability

1. Compression molding requires good flow, slow curing speed, high molding temperature.

2. After compression molding, it needs to be cured at high temperature.

Source: Application of Engineering Plastics

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