Engineering plastics physical properties processing application, worth collecting

Published on:

2023-08-07

Excellent electrical insulation (especially high frequency insulation), colorless and transparent, light transmittance second only to plexiglass, color resistance to water, good chemical stability. The strength is general, but the quality is brittle, easy to produce stress brittle cracking, not resistant to benzene. Gasoline and other organic solvents.

Engineering plastics physical properties processing application, worth collecting

1. ABS plastic

2. PS plastic

3. PMMA plastic (plexiglass)

4. POM plastic

5. PP plastic

6. PE plastic

7. PVC

8. PA plastic (nylon)

9. PC plastic

10. PPO plastic (MPPO)

11. PSU plastic

12. PTFE plastic (F4)

13. ASA plastic

14. PPS plastic

15. ETFE plastic

16. PFA plastic

17. PAR plastic (U plastic)

18. Phenolic plastic

19. Aminoplastics

20. Epoxy resin (EP)

21. Silicone plastic (IS)

ABS plastic
English name: Acrylonitrile Butadiene Styrene		(Acrylonitrile-Butadiene-Styrene)
Specific gravity: 1.05g/cubic centimeter Molding shrinkage: 0.4-0.7% Molding temperature: 200-240℃ Drying conditions: 80-90℃ 2 hours
Material properties	1. It has good comprehensive performance, high impact strength, chemical stability and good electrical properties.	Suitable for making general mechanical parts, wear-reducing and wear-resistant parts, transmission parts and telecommunications parts.
	2. It has good weldability with 372 organic glass and can be made into two-color plastic parts, and the surface can be chrome-plated and spray-painted.
	3. There are 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.
Molding performance	1. Amorphous material, medium fluidity, high moisture absorption, must be fully dried. Plastic parts that require glossy surface must be preheated and dried for a long time at 80-90 degrees for 3 hours.
	2. It is advisable to choose a high material temperature and a high mold temperature, but if the material temperature is too high, it will easily decompose (the decomposition temperature is >270 degrees). For plastic parts with higher precision, the mold temperature should be 50-60 degrees. For high-gloss and durable plastic parts, For thermoplastic parts, the mold temperature should be 60-80 degrees.
	3. If you need to solve the problem of water marks, you need to improve the fluidity of the material, adopt methods such as high material temperature, high mold temperature, or change the water inlet level.
	4. If heat-resistant or flame-retardant materials are formed, plastic decomposition will remain on the mold surface after 3-7 days of production, causing the mold surface to shine. The mold needs to be cleaned in time, and an exhaust position needs to be added to the mold surface.

PS plastic
English name:Polystyrene		(polystyrene)
Specific gravity: 1.05 g/cubic centimeter Molding shrinkage: 0.6-0.8% Molding temperature: 170-250℃ Drying conditions: ---
Material properties	It has excellent electrical insulation (especially high-frequency insulation), is colorless and transparent, has light transmittance second only to organic glass, is colorable and water-resistant, and has good chemical stability. It has average strength, but is brittle and prone to stress brittleness. Resistant to benzene, gasoline and other organic solvents.	Suitable for making insulating transparent parts, decorative parts, chemical instruments, optical instruments and other parts.
Molding performance	1. Amorphous material, has low moisture absorption, does not need to be fully dried, and is not easy to decompose, but has a large thermal expansion coefficient and is prone to internal stress. It has good fluidity and can be molded by a screw or plunger injection machine.
	2. It is appropriate to use high material temperature, high mold temperature, low injection pressure, and extending the injection time will help reduce internal stress and prevent shrinkage and deformation.
	3. Various forms of gates can be used, and the gates are connected with the arc of the plastic parts to avoid damaging the plastic parts when removing the gate. The demoulding angle is large and the ejection is uniform. The wall thickness of the plastic parts is uniform, and it is best not to have inserts. If there are inserts, they should be preheated.

PMMA plastic (plexiglass)
English name:Polymethyl Methacrylate		(polymethylmethacrylate)
Specific gravity: 1.18 g/cm3 Molding shrinkage: 0.5-0.7% Molding temperature: 160-230℃ Drying conditions: 70-90℃ 4 hours
Material properties	It has excellent transparency, high strength, certain heat and cold resistance, corrosion resistance, and good insulation. Its overall performance exceeds that of polystyrene, but it is brittle and easily melted in organic solvents. If it is used as a light-transmitting material, its surface hardness Slightly lower, easy to scratch.	Suitable for making transparent insulating parts and parts with average strength.
Molding performance	1. Amorphous material, has high moisture absorption, needs to be dried, is not easy to decompose, has medium fluidity, and is prone to poor filling, mold sticking, shrinkage, welding marks, etc.
	2. It is advisable to use high-pressure injection, high material temperature and high mold temperature without defects to increase fluidity, reduce internal stress, and improve transparency and strength. The surface of the mold pouring system should be smooth and clean, with a large demoulding slope. Eject evenly. At the same time, provide an exhaust port to prevent bubbling.

POM plastic
English name:Polyoxymethylene(Polyformaldehyde)		(polyoxymethylene)
Specific gravity: 1.41-1.43 g/cubic centimeter Molding shrinkage: 1.2-3.0% Molding temperature: 170-200℃ Drying conditions: 80-90℃ 2 hours
Material properties	It has good comprehensive performance, high strength and stiffness, good wear reduction and wear resistance, low water absorption, and good dimensional stability. However, it has poor thermal stability, is easy to burn, and is prone to aging when exposed to the atmosphere.	Suitable for making wear-reducing and wear-resistant parts, transmission parts, chemical industry, instrumentation and other parts
Molding performance	1. Crystalline material has a narrow melting range, fast melting and solidification, and crystallization occurs when the material temperature is slightly lower than the melting temperature. Liquidity is medium. It absorbs little moisture and can be used without drying.
	2. Low friction coefficient and good elasticity, the surface of plastic parts is prone to surface defects such as wrinkles.
	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.

PP plastic
English name:Polypropylene		(polypropylene)
Specific gravity: 0.9-0.91g/cubic centimeter Molding shrinkage: 1.0-2.5% Molding temperature: 160-220℃ Drying conditions: ---
Material properties	Its density is small, its strength, stiffness, hardness and heat resistance are better than low-pressure polyethylene, and it can be used at around 100 degrees. It has good electrical properties and high-frequency insulation and is not affected by humidity, but it becomes brittle at low temperatures, is not resistant to molds and is prone to aging. .	Suitable for making general mechanical parts, corrosion-resistant parts and insulating parts
Molding performance	1. Crystalline material has low hygroscopicity, is prone to melt rupture, and is prone to decomposition in long-term contact with hot metal.
	2. The fluidity is good, but the shrinkage range and value are large, and shrinkage cavities, dents, and deformation are prone to occur.
	3. The cooling speed is fast, the pouring system and cooling system should dissipate heat slowly, and pay attention to controlling the molding temperature. The directionality is obvious when the material temperature is low. It is especially obvious at low temperature and high pressure. When the mold temperature is lower than 50 degrees, the plastic parts are not smooth and are easy to produce Poor welding, leaving marks, and prone to warping and deformation above 90 degrees.
	4. The plastic wall thickness must be uniform to avoid lack of glue and sharp corners to prevent stress concentration.

PE plastic
English name:Polyethylene		(polyethylene)
Specific gravity: 0.94-0.96 g/cubic centimeter Molding shrinkage: 1.5-3.6% Molding temperature: 140-220℃ Drying conditions: ---
Material properties	It has excellent corrosion resistance and electrical insulation (especially high-frequency insulation). It can be chlorinated, irradiated, modified, and reinforced with glass fiber. Low-voltage polyethylene has high melting point, rigidity, hardness and strength, low water absorption, and good It has excellent electrical properties and radiation resistance; high-pressure polyethylene has good flexibility, elongation, impact strength and permeability; ultra-high molecular weight polyethylene has high impact strength, fatigue resistance and wear resistance.	Low-pressure polyethylene is suitable for making corrosion-resistant parts and insulating parts; high-pressure polyethylene is suitable for making films, etc.; ultra-high molecular weight polyethylene is suitable for making shock-absorbing, wear-resistant and transmission parts.
Molding performance	1. Crystalline material has low moisture absorption, does not need to be fully dried, and has excellent fluidity. The fluidity is sensitive to pressure. It is suitable to use high-pressure injection during molding. The material temperature is uniform, the filling speed is fast, and the pressure is sufficient. It is not suitable to use direct gates to prevent shrinkage. Uneven, internal stress increases. Pay attention to the location of the gate to prevent shrinkage cavities and deformation.
	2. The shrinkage range and value are large, the directionality is obvious, and it is easy to deform and warp. The cooling speed should be slow, and the mold should be equipped with a cold material cavity and a cooling system.
	3. The heating time should not be too long, otherwise decomposition and burns may occur.
	4. When soft plastic parts have shallow side grooves, they can be forcibly demoulded.
	5. Melt rupture may occur and should not be in contact with organic solvents to prevent cracking.

PVC
English name:Poly(Vinyl Chloride)		PVC
Specific gravity: 1.38 g/cubic centimeter Molding shrinkage: 0.6-1.5% Molding temperature: 160-190℃ Drying conditions: ---
Material properties	It has excellent mechanical properties and electrical properties, strong acid and alkali resistance, good chemical stability, but low softening point.	Suitable for making thin plates, wire and cable insulation layers, seals, etc.
Molding performance	1. Amorphous material, with low moisture absorption and poor fluidity. In order to improve fluidity and prevent bubbles, the plastic can be dried in advance. The mold pouring system should be thick and short, the gate cross-section should be large, and there should be no dead corners. The mold must be cooled and the surface should be chromium-plated.
	2. It is extremely easy to decompose. It is more likely to decompose when in contact with steel and copper at a temperature of 200 degrees. It will release corrosive and irritating gases during decomposition. The molding temperature range is small.
	3. When using a screw injection machine nozzle, the hole diameter should be large to prevent material stagnation in dead corners. It is best not to use inserts. If there are inserts, they should be preheated.

PA plastic (nylon)
English name:Polyamide		(Polyamide)
Specific gravity: PA6-1.14g/cm3 PA66-1.15g/cm3 PA1010-1.05g/cm3 Molding shrinkage: PA6-0.8-2.5% PA66-1.5-2.2% Molding temperature: 220-300℃ Drying conditions: 100 -110℃ 12 hours
Material properties	Tough, wear-resistant, oil-resistant, water-resistant, and enzyme-resistant, but absorbs large amounts of water.	Suitable for making general mechanical parts, wear-reducing and wear-resistant parts, transmission parts, as well as chemical, electrical, instrument and other parts
	Nylon 6 has good elasticity, high impact strength and large water absorption.
	Nylon 66 has better performance than nylon 6, with high strength and good wear resistance.
	Nylon 610 is similar to nylon 66, but has less water absorption and lower stiffness.
	Nylon 1010 is translucent, has low water absorption and good cold resistance.
Molding performance	1. Crystalline materials have high melting points, narrow melting temperature ranges, and poor thermal stability. They will decompose when the material temperature exceeds 300 degrees and the residence time exceeds 30 minutes. It is easy to absorb moisture and needs to be dried. The moisture content should not exceed 0.3%.
	2. Good fluidity and easy to overflow. It is advisable to use self-locking nozzles and should be heated.
	3. The molding shrinkage range and shrinkage rate are large, the directionality is obvious, and shrinkage holes, deformation, etc. are prone to occur.
	4. The mold temperature is selected within the range of 20-90 degrees according to the wall thickness of the plastic part, the injection pressure is selected according to the injection machine type, material temperature, shape and size of the plastic part, and the mold pouring system, and the molding cycle is selected according to the wall thickness of the plastic part. When the resin viscosity is small, the injection and cooling times should be longer, and white oil should be used as the release agent.
	5. The form and size of the mold pouring system. Increasing the size of the runner and gate can reduce shrinkage.

PC plastic
English name:Polycarbonate		(polycarbonate)
Specific gravity: 1.18-1.20 g/cubic centimeter Molding shrinkage: 0.5-0.8% Molding temperature: 230-320℃ Drying conditions: 110-120℃ 8 hours
Material properties	High impact strength, good dimensional stability, colorless and transparent, good colorability, good electrical insulation, corrosion resistance, and wear resistance, but poor self-lubricating, prone to stress cracking, easy to hydrolyze at high temperatures, and poor compatibility with other resins .	Suitable for making small instrument parts, insulating transparent parts and impact-resistant parts
Molding performance	1. Amorphous material, good thermal stability, wide molding temperature range, poor fluidity. It absorbs little moisture but is sensitive to water and must be dried. The molding shrinkage is small and melt cracking and stress concentration are prone to occur, so the molding conditions should be strictly controlled and the plastic parts must be annealed.
	2. For plastic parts with high melting temperature and high viscosity, larger than 200g, a heated extension nozzle should be used.
	3. The cooling speed is fast, the mold pouring system should be thick and short, a cold well should be set up, the gate should be large, and the mold should be heated.
	4. If the material temperature is too low, it will cause material shortage and the plastic parts will be dull. If the material temperature is too high, it will easily overflow and the plastic parts will blister. When the mold temperature is low, the shrinkage, elongation, and impact strength are high, but the bending resistance, compression resistance, and tensile strength are low. When the mold temperature exceeds 120 degrees, the plastic parts cool slowly and are prone to deformation and sticking to the mold.

PPO plastic (MPPO)
English name:poly(phenylene oxide)		(polyphenylene ether)
Specific gravity: 1.07 g/cubic centimeter 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.	1. Suitable for making heat-resistant parts, insulation parts, wear-reducing and wear-resistant parts, transmission parts, medical and electronic parts.
	2. It has outstanding electrical insulation and water resistance, and good dimensional stability. Its dielectric properties rank first among plastics.
	3. MPPO is a modified material made by blending PPO and HIPS. All materials currently on the market are this kind of material.	2. It can be used as gears, blades, valves and other parts used at higher temperatures, and can be used instead of stainless steel.
	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, and the heat distortion temperature can reach 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.	3. Can make screws, fasteners and connectors.
	6. Can be used with ABS, HDPE, PPS, PA,	4. Electrical parts of motors, rotors, casings, and transformers.

	HIPS, glass fiber, etc. are blended and modified.
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 strands 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.

PSU plastic
English name:Polysulfone		(polysulfone)
Specific gravity: 1.25-1.35 g/cubic centimeter Molding shrinkage: 0.5-0.7% Molding temperature: 290-350℃ Drying conditions: 130-150℃ 4 hours
Material performance/purpose	1. Polysulfone is an amber transparent solid material with high hardness and impact strength. It is non-toxic, has good heat and cold resistance and aging resistance. It can be used for a long time at -100--175 degrees. Resistant to corrosion by inorganic acids, alkalis and salts, but not resistant to aromatic hydrocarbons and halogenated hydrocarbons. Polyarylsulfone has high hardness, radiation resistance, good heat and cold resistance and self-interesting properties, and can be used for a long time at -100-175 degrees.	1. Suitable for making heat-resistant parts, insulation parts, wear-reducing and wear-resistant parts, instrument parts and medical device parts. Polyarylsulfone is suitable for making low-temperature working parts.
		2. Polysulfone is commonly used in the electronic and electrical industry to manufacture integrated circuit boards, coil tube frames, contactors, sleeves, capacitor films, and high-performance alkaline battery casings.
	2. The wear resistance of the material can be greatly improved through glass fiber reinforcement modification.	3. Polysulfone is used in household appliances such as microwave oven equipment, coffee heaters, humidifiers, hair dryers, cloth steam dryers, beverage and food dispensers, etc. It can also be used in precision structural parts of watches, copiers, cameras, etc. instead of non-ferrous metals.
	3. Polysulfone can be made into modified products of polysulfone with ABS, polyimide, polyetheretherketone and fluoroplastics, mainly to improve its impact strength, elongation, solvent resistance, environmental resistance, processing performance and plateability. Such as PSF/PBT, PSF/ABS, PSF+mineral powder.	4. Polysulfone has passed the relevant specifications in the pharmaceutical and food fields of the United States and can replace stainless steel products. Because polysulfone is steam-resistant, hydrolysis-resistant, non-toxic, resistant to high-temperature steam sterilization, highly transparent, and has good dimensional stability, it can be used as surgical tool trays, sprayers, fluid controllers, heart valves, pacemakers, gas masks, Dental trays etc.
Molding performance	1. Amorphous material, highly hygroscopic, with a water absorption rate of 0.2%-0.4%. It must be fully dried before use and prevented from absorbing moisture again. Ensure the moisture content is below 0.1%.
	2. The molding performance is similar to PC, but the thermal stability is poor and decomposition begins at 360 degrees.
	3. Poor fluidity and fast cooling, so it is suitable for molding at high temperature and high pressure. The mold should have sufficient strength and rigidity, a cold well should be installed, the runner should be short, and the gate size should be 1/2-1/3 of the wall thickness of the plastic part.
	4. In order to reduce the internal stress caused by injection molded products, the mold temperature should be controlled at 100-140 degrees. After molding, annealing treatment can be performed in a glycerin bath at 160 degrees for 1-5 minutes; or in an air bath at 160 degrees for 1-4 hours. Annealing time depends on the size and wall thickness of the part.
	5. Polysulfone is close to Newtonian body in the molten state, similar to polycarbonate, and its fluidity is sensitive to temperature. Within 310 degrees to 420 degrees, the fluidity will double for every 30 degrees increase in temperature. Therefore, the processing fluidity is mainly improved by increasing the temperature during molding.


PTFE plastic (F4)
English name:Polytetrafluoroethylene		(polytetrafluoroethylene)
Specific gravity: 2.1-2.2 g/cubic centimeter Molding shrinkage: 3.1-7.7% Molding temperature: 330-380℃ Drying conditions: ---
Material properties	1. Long-term use temperature is -200--260 degrees. It has excellent chemical resistance and is resistant to all chemicals. The friction coefficient is the lowest among plastics. It also has good electrical properties. Its electrical insulation is not affected by temperature. Due to its influence, it is known as the "King of Plastics".	Suitable for making corrosion-resistant parts, wear-reducing and wear-resistant parts, seals, insulation parts and medical device parts
	2. It is transparent or translucent. The higher the crystallinity, the worse the transparency. The raw materials are mostly powdered resin or concentrated dispersion, which are thermoplastic polymers with extremely high molecular weight and high crystallinity.
Molding performance	1. Crystalline material, low moisture absorption.
	2. It has poor fluidity and is easily decomposed, producing corrosive gas during decomposition. The molding temperature should be strictly controlled, the mold should be heated, and the pouring system should have small resistance to material flow.
	3. Powdered resin is often formed using powder metallurgy and sintering methods. The sintering temperature is 360-380 degrees and cannot exceed 475 degrees. Emulsion resin is usually processed by cold extrusion and then sintering, which can form an anti-corrosion layer on the surface of the object. If the product requires transparency and good toughness, rapid cooling should be adopted. Extrusion molding can also be used, and tubes, rods, and profiles can be extruded.
	4. The melt viscosity of PTFE is very high, and the volume viscosity decreases with the increase of shear stress, showing its non-Newtonian fluid characteristics.
	5. Secondary processing, including hot pressing compounding, welding, bonding, reinforcement, mechanical processing, etc., to obtain the final product.

ASA plastic

English name: Acrylonitrile Styrene acrylate copolymer		(Acrylic-styrene-acrylonitrile)
Specific gravity: 1.05 g/cm3 Molding shrinkage: 0.4-0.7% Molding temperature: 170-230℃ Drying conditions: 80-90℃ 2 hours
Material properties	ASA polymers are amorphous materials that can be extruded and injection molded into products that are extremely resistant to the effects of weathering. The mechanical properties of terpolymer ASA are generally similar to ABS resin, except that the performance of ASA is much less affected by outdoor climate than ABS resin.	Suitable for making general construction fields, outdoor furniture, and car exterior mirror casings
Molding performance	1. Amorphous material, medium fluidity, high moisture absorption, must be fully dried. Plastic parts that require glossy surface must be preheated and dried for a long time at 80-90 degrees for 3 hours.
	2. It is advisable to use high material temperature and high mold temperature, but if the material temperature is too high, it will easily decompose (decomposition temperature is >250 degrees). For plastic parts with higher precision, the mold temperature should be 50-60 degrees, which is good for gloss and heat resistance. For plastic parts, the mold temperature should be 60-80 degrees.
	3. The brands of ASA basic resins sold on the market are: Luran S brand (BASF Plastic Materials Company); Gelog brand (General Plastics Company); Centrex brand (Monsanto Company).

PPS plastic
English name:Phenylene sulfide		(Polyphenylene sulfide)
Specific gravity: 1.36 g/cm3 Molding shrinkage: 0.7% Molding temperature: 300-330℃ Drying conditions: ---
Material properties	1. Excellent electrical insulation (especially high-frequency insulation), white hard and brittle, making a metallic sound when dropped on the ground, light transmittance second only to organic glass, coloring, water resistance, and good chemical stability. It has excellent flame retardancy and is a non-combustible plastic.	Suitable for making heat-resistant parts, insulation parts, chemical instruments, optical instruments and other parts.
	2. It has average strength and good rigidity, but is brittle and prone to stress brittle cracking. It is not resistant to benzene, gasoline and other organic solvents. The long-term use temperature can reach 260 degrees, and remains stable in air or nitrogen at 400 degrees. After modification by adding glass fiber or other reinforcing materials, the impact strength can be greatly improved, the heat resistance and other mechanical properties are also improved, the density is increased to 1.6-1.9, and the molding shrinkage is as small as 0.15-0.25%.
Molding performance	1. Amorphous material, low moisture absorption, but should be dried before molding.
	2. The fluidity is between ABS and PC, with fast solidification, small shrinkage and easy decomposition. Choose higher injection pressure and injection speed. The mold temperature should be 100-150 degrees. The taper of the main flow channel should be large and the flow channel should be short.

ETFE plastic
English name:Polytetrafluoroethylene		(Polytetrafluoroethylene-ethylene copolymer)
Specific gravity: 1.7 g/cubic centimeter Molding shrinkage: 3.1-7.7% Molding temperature: 300-330℃ Drying conditions: ---
Material properties	1. Long-term use temperature -80-220 degrees, excellent chemical resistance, corrosion resistance to all chemicals, the lowest friction coefficient among plastics, and good electrical properties, its electrical insulation is not affected by temperature Due to its influence, it is known as the "King of Plastics".	1. Suitable for making corrosion-resistant parts, wear-reducing and wear-resistant parts, seals, insulation parts and medical device parts.
	2. Its chemical resistance is similar to that of polytetrafluoroethylene and better than vinylidene fluoride.
	3. Its creep resistance and compressive strength are better than those of polytetrafluoroethylene, its tensile strength is high, and its elongation can reach 100-300%. Good dielectric properties and excellent radiation resistance.	2. Wire and cable insulation layers, anti-corrosion equipment, sealing materials, pump valve bushings, and chemical containers.
Molding performance	1. Crystalline material, low moisture absorption. It can be processed into products using usual thermoplastic processing methods.
	2. It has poor fluidity and is easily decomposed, producing corrosive gas during decomposition. The molding temperature should be strictly controlled not to exceed 350 degrees, the mold should be heated to 100-150 degrees, and the pouring system should have small resistance to material flow. It can form thin-walled simple products with a thickness of 0.7-0.8 mm.
	3. Transparent pellets, injection molding, extrusion molding. The molding temperature is 300-330 degrees. Above 350 degrees, it is easy to cause discoloration or bubbles. It is advisable to mold at high speed and low pressure, and be aware that demolding will be difficult.

PFA plastic
English name:Polytetrafluoroethylene		(Soluble polytetrafluoroethylene)
Specific gravity: 2.13-2.167 g/cubic centimeter Molding shrinkage: 3.1-7.7% Molding temperature: 350-400℃ Drying conditions: ---
Material properties	1. It is a copolymer of a small amount of perfluoropropyl perfluorovinyl ether and polytetrafluoroethylene. The melt adhesion is enhanced, the solution viscosity is reduced, and the performance remains unchanged compared with PTFE. This kind of resin can be directly processed into products using ordinary thermoplastic molding methods.	1. Suitable for making corrosion-resistant parts, wear-reducing and wear-resistant parts, seals, insulation parts and medical device parts.
	2. Long-term use temperature -80--260 degrees, excellent chemical resistance, corrosion resistance to all chemicals, the lowest friction coefficient among plastics, and good electrical properties, its electrical insulation is not affected by temperature Due to its influence, it is known as the "King of Plastics".
	2. Its chemical resistance is similar to that of polytetrafluoroethylene and better than vinylidene fluoride.	2. High-temperature wires and cable insulation layers, anti-corrosion equipment, sealing materials, pump valve bushings, and chemical containers.
	3. Its creep resistance and compressive strength are better than those of polytetrafluoroethylene, its tensile strength is high, and its elongation can reach 100-300%. Good dielectric properties and excellent radiation resistance. The flame retardancy reaches V0 level.
Molding performance	1. Crystalline material, low moisture absorption. It can be processed into products using usual thermoplastic processing methods.
	2. It has poor fluidity and is easily decomposed, producing corrosive gas during decomposition. The molding temperature should be strictly controlled not to exceed 475 degrees, the mold should be heated to 150-200 degrees, and the pouring system should have small resistance to material flow.
	3. Translucent pellets, injection molding, extrusion molding. The molding temperature is 350-400 degrees. Above 475 degrees, it is easy to cause discoloration or bubbles. And note that demoulding will be difficult.
	4. Because molten materials corrode metals, the molds require chromium plating for long-term production.

PAR plastic (U plastic)
English name:		(polyarylate)
Specific gravity: 1.2-1.26 g/cubic centimeter Molding shrinkage: 0.8% Molding temperature: 300-350℃ Drying conditions: 100～120℃-5 hours
Material properties	1. It is a transparent amorphous thermoplastic engineering plastic with excellent heat resistance, flame retardancy and non-toxicity. It can be directly processed into products using ordinary thermoplastic forming methods.	1. Suitable for making electrical parts that are heat-resistant, flame-resistant and have high dimensional stability. Connectors, coil formers, relay housings.
	2. It has excellent thermal properties. Under a load of 1.86MPA, its heat deformation temperature is as high as 175 degrees and its decomposition temperature is 443 degrees. Its various mechanical properties are less affected by temperature.
		2. Lighting parts. Can be made into transparent lampshades, illuminators, car reflectors, etc.
Molding performance	1. As the wall thickness of the product increases, the molding shrinkage rate increases.
	2. The hygroscopicity is small, about 0.1-0.3%, but trace amounts of moisture will cause polyarylate to decompose during injection molding. Therefore, the material must be dried before molding. Make its moisture content less than 0.02%.

Phenolic plastic
English name: Phenol-Formaldehyde(PF)
Specific gravity: 1.5-2.0 g/cubic centimeter Molding shrinkage: 0.5-1.0% Molding temperature: 150-170℃
Material properties	Phenolic plastic is a hard and brittle thermosetting plastic, commonly known as bakelite powder. It has high mechanical strength, toughness and wear resistance, dimensional stability, corrosion resistance and excellent electrical insulation properties.	Suitable for making insulator components for electrical appliances and instruments, and can be used under hot and humid conditions
Molding performance	1. The formability is good, but the shrinkage and directionality are generally greater than those of aminoplastics, and they contain moisture volatiles. It should be preheated before molding, and the air should be exhausted during the molding process. If not preheated, the mold temperature and molding pressure should be increased.
	2. Mold temperature has a great influence on fluidity. Generally, when it exceeds 160 degrees, fluidity will decrease rapidly.
	3. The hardening speed is generally slower than that of aminoplastics, and the heat released during hardening is large. The internal temperature of large thick-walled plastic parts is easily too high, and uneven hardening and overheating are prone to occur.

Aminoplastic
English name: MF, UF
Specific gravity: 1.5 g/cubic centimeter Molding shrinkage: 0.6-1.0% Molding 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 parts
Molding performance	1. It has good fluidity and fast hardening speed, so the preheating and molding temperatures must be appropriate, and the coating, mold closing and pressurizing speeds must be fast.
	2. The molding shrinkage is large.
	3. It contains a lot of moisture and volatile matter, and is easy to absorb moisture and agglomerate. It should be preheated and dried during molding to prevent re-absorption of moisture. However, if it is too dry, the fluidity will decrease. There is moisture and decomposition products during molding, and there is acidity. The mold should be chromium-plated to prevent corrosion, and exhaust should be exhausted during molding.
	4. The molding temperature has a great influence on the quality of plastic parts. If the temperature is too high, decomposition, discoloration, and uneven color of bubbles will occur easily. If the temperature is too low, the fluidity will be poor and it will not be shiny.
	5. The material is fine, the specific volume is large, and there is a lot of air in the material. When using a pre-pressed ingot to form large plastic parts, it is easy to produce ripples and flow lines, so it is generally not suitable to use it.

Epoxy resin (EP)
English name:Epoxide Resin
Specific gravity: 1.9 g/cubic centimeter Molding shrinkage: 0.5% Molding temperature: 140-170℃
Material properties	It has good mechanical properties, electrical insulation, chemical stability, and strong adhesion to many materials, but its performance is affected by filler type and content. Alicyclic cluster epoxy plastics have higher heat resistance. Suitable for casting and low pressure extrusion molding	Suitable for potting and fixing electricians, electronic components and coils, and can also be used for repairs
Molding performance	1. Castable. It has good fluidity and small hardening shrinkage, but has poor thermal rigidity and is difficult to demould.
	2. The hardening speed is fast, and generally no exhaust is required during hardening. Pressure should be applied immediately after loading.

Silicone plastic (IS)
English name: Silicone
Specific gravity: 1.75-1.95 g/cubic centimeter Molding shrinkage: 0.5% Molding temperature: 160-180℃
Material properties	High and low temperature resistance, good water resistance, good high frequency insulation, good radiation resistance and ozone resistance	Suitable for potting and fixing electricians, electronic components and coils
Molding performance	1. Good fluidity and slow hardening speed, requiring higher molding temperature during compression molding.
	2. After compression molding, it must be cured at high temperature.

Screw disassembly, installation, production, regular inspection, shutdown and storage of detailed steps

Application of cylinder temperature control

Screw disassembly, installation, production, regular inspection, shutdown and storage of detailed steps

Application of cylinder temperature control