Counting the Typical Applications and Physical Properties of 22 Commonly Used Plastics

Plastic is a synthetic material made from synthetic resins that can be molded according to the required shape. Plastic is widely used for various purposes, including manufacturing packaging materials, household appliances, and building materials. Plastics are generally classified into many types, each with its unique characteristics.  We are an experienced plastic extrusion line supplier, specializing in the supply of lines like China PP hollow sheet extrusion line, pvc trunking extrusion line and so on. Let's share some useful information about plastics for you.

PC/ABS (Polycarbonate/Acrylonitrile Butadiene Styrene) copolymers and blends

Typical applications:

Computer and business machine housings, electrical equipment, lawn and garden equipment, automotive parts, dashboards, interior decorations, and wheel covers.

Chemical and physical properties:

PC/ABS combines the properties of both PC and ABS. It possesses the easy processing characteristics of ABS and the excellent mechaical properties and thermal stability of PC. The ratio of PC to ABS affects the thermal stability of PC/ABS materials. This mixed material also exhibits outstanding flow properties.

PC/PBT (Polycarbonate/Polybutylene Terephthalate) blends

Typical applications: Gearboxes, automotive bumpers, and products requiring chemical resistance, corrosion resistance, thermal stability, impact resistance, and dimensional stability.

Chemical and physical properties: PC/PBT combines the properties of PC and PBT. It has the high toughness and dimensional stability of PC, as well as the chemical stability, thermal stability, and lubricity of PBT.

PE-HD (High-Density Polyethylene)

Chemical and Physical Properties:

The high crystallinity of PE-HD results in its high density, tensile strength, high temperature distortion temperature, viscosity, and chemical stability. PE-HD has stronger resistance to permeation compared to PE-LD. However, its impact resistance is lower. The characteristics of PE-HD are mainly controlled by its density and molecular weight distribution.

This material exhibits good flow properties with a melt flow rate (MFR) ranging from 0.1 to 28. As the molecular weight increases, the flow properties of PE-HD become poorer, but it exhibits better impact resistance. PE-HD is a semi-crystalline material with relatively high post-molding shrinkage, ranging from 1.5% to 4%. It is susceptible to environmental stress cracking, which can be mitigated by using materials with low flow properties to reduce internal stresses and minimize cracking. When the temperature exceeds 60°C, PE-HD is susceptible to dissolution in hydrocarbon solvents, but it exhibits better solvent resistance compared to PE-LD.

PE-LD (Low-Density Polyethylene)

Typical applications:

Bowls, cabinets, and pipe connectors.

Chemical and physical properties:

Commercial LDPE materials have a density of 0.91 to 0.94g/cm³. LDPE is permeable to gases and water vapor. Its high coefficient of thermal expansion makes it unsuitable for long-term use in processing. LDPE has good resistance to various solvents at room temperature but can swell in aromatic hydrocarbons and chlorinated hydrocarbon solvents. Similar to HDPE, LDPE is susceptible to environmental stress cracking.

PEI (Polyetherimide)

Typical applications: 

Automotive industry (temperature sensors, fuel and air processors), electrical and electronic devices (electrical connectors, printed circuit boards, chip casings, explosion-proof boxes), product packaging, aircraft interior equipment, medical instruments, tool casings, non-implantable devices

Chemical and physical properties: 

PEI has strong high-temperature stability, even in the non-reinforced form, it still possesses good toughness and strength. It exhibits good flame resistance, chemical resistance, and electrical insulation properties. PEI has a high glass transition temperature of 215°C and low shrinkage with excellent isotropic mechanical properties.

ABS (Acrylonitrile Butadiene Styrene) plastic

Typical applications: 

Automotive (dashboards, glove compartments, wheel covers, side mirrors, etc.), refrigerators, high-strength tools (hairdryers, blenders, food processors, lawnmowers, etc.), telephone casings, typewriter keyboards, recreational vehicles like golf carts and jet snowplows.

Chemical and physical properties: 

ABS is composed of three chemical monomers: acrylonitrile, butadiene, and styrene. Each monomer contributes different characteristics: acrylonitrile provides high strength, thermal stability, and chemical resistance; butadiene imparts toughness and impact resistance, and styrene offers easy processing, high gloss, and strength. ABS is a non-crystalline material with a two-phase structure of styrene-acrylonitrile as the continuous phase and dispersed phase of polybutadiene rubber. The properties of ABS depend on the ratios of the three monomers and the molecular structure in the two phases, allowing for great flexibility in product design, resulting in a wide range of ABS materials in the market. These materials offer different properties, such as varying impact resistance from medium to high, different levels of gloss, and high-temperature distortion characteristics. ABS materials are known for their excellent processability, appearance, low creep, outstanding dimensional stability, and high impact strength.

PA12 Polyamide 12 or Nylon 12 

Typical applications:

Water meters and other commercial equipment, cable sheathing, mechanical cams, sliding mechanisms, and bearings, among others.

Chemical and physical properties:

PA12 is a linear, semi-crystalline thermoplastic material derived from butadiene. Its characteristics are similar to PA11, but the crystal structure is different. PA12 is an excellent electrical insulator and, like other polyamides, its insulation properties are not affected by moisture. It has good impact resistance and chemical stability. PA12 has various improved grades in terms of plasticization and reinforcement properties. Compared to PA6 and PA66, these materials have lower melting points and densities, with a very high moisture absorption rate. PA12 is not resistant to strong oxidizing acids. Its viscosity depends on humidity, temperature, and storage time. It has good flowability. The shrinkage rate is between 0.5% to 2%, depending on the material grade, wall thickness, and other processing conditions.

PA6 Polyamide 6 or Nylon 6 

Typical applications:

Due to its good mechanical strength and stiffness, PA6 is widely used in structural components. It also has excellent wear resistance and is used in the manufacturing of bearings.

Chemical and physical properties:

PA6 has similar chemical and physical properties to PA66, but it has a lower melting point and a wider processing temperature range. It has better impact resistance and solvent resistance compared to PA66, but its moisture absorption is higher. The qualities of plastic parts are influenced by their moisture absorption, so it's essential to consider this when designing products with PA6. To enhance the mechanical properties of PA6, various modifiers are frequently added.

Glass is the most common additive, and sometimes synthetic rubbers like EPDM and SBR are added to improve impact resistance. Unfilled PA6 has a shrinkage rate of about 1% to 1.5%. Adding glass fiber reduces the shrinkage rate to about 0.3% (but slightly higher in the direction perpendicular to the flow). The shrinkage rate during molding is mainly affected by the material's crystallinity and moisture absorption. The actual shrinkage rate also depends on the part design, wall thickness, and other process parameters.

PA66 Polyamide 66 or Nylon 66 

Typical applications:

Compared to PA6, PA66 is more widely used in the automotive industry, instrument housings, and other products that require impact resistance and high strength.

Chemical and physical properties:

PA66 has a higher melting point compared to other polyamides. It is a semi-crystalline material with retained strength and stiffness at higher temperatures. PA66 retains its moisture absorption even after molding, and its degree depends on the material composition, wall thickness, and environmental conditions. It has good mechanical properties but lower flowability compared to PA6.

PA66 has low viscosity, providing good flowability (though not as good as PA6). Its viscosity is sensitive to temperature changes. The shrinkage rate of PA66 is between 1% to 2%. Adding glass fiber can reduce the shrinkage rate to about 0.2% to 1%. The shrinkage rate is significantly different between the flow direction and the direction perpendicular to the flow. PA66 has resistance to many solvents but is weak against acids and some chlorine-based agents.

PBT Polybutylene Terephthalate 

Typical applications:

Home appliances (food processing blades, vacuum cleaner components, electric fans, hair dryer casings, coffee containers, etc.), electrical components (switches, motor housings, fuse boxes, computer keyboard keys, etc.), automotive industry (radiator grilles, body panels, wheel covers, door and window components, etc.).

Chemical and physical properties:

PBT is one of the toughest engineering thermoplastic materials. It is a semi-crystalline material with excellent chemical stability, mechanical strength, electrical insulation properties, and thermal stability. PBT exhibits good stability under a wide range of environmental conditions and has weak moisture absorption. The tensile strength of unfilled PBT is around 50 MPa, while glass-filled PBT can reach up to 170 MPa. Excessive glass filler can lead to material brittleness. PBT crystallizes rapidly, which can cause warping due to uneven cooling.

For materials with glass filler, the shrinkage rate in the flow direction can be reduced, but the shrinkage rate perpendicular to the flow direction is essentially the same as regular materials. The typical shrinkage rate for general materials is between 1.5% to 2.8%. For materials with 30% glass filler, the shrinkage rate is between 0.3% to 1.6%. PBT has a lower melting point (around 225°C) and a lower heat distortion temperature compared to PET. The Vicat softening temperature is approximately 170°C. The glass transition temperature ranges from 22°C to 43°C. Due to its high crystallization rate, PBT has low viscosity, resulting in shorter molding cycles.

PC Polycarbonate 

Typical applications:

Electrical and commercial equipment (computer components, connectors, etc.), medical industry, appliances (food processing machines, refrigerator drawers, etc.), transportation industry (vehicle headlights, dashboards, etc.).

Chemical and physical properties:

PC is an amorphous engineering material with excellent impact strength, thermal stability, glossiness, antibacterial properties, flame retardancy, and resistance to pollution. PC has very high notch Izod impact strength and low shrinkage (typically around 0.1% to 0.2%). It has good mechanical properties but poor flowability.

PC has good heat resistance and low-temperature resistance, with stable mechanical, dimensional, electrical, and flame retardant properties over a wide temperature range (-60 to 120°C). It has no distinct melting point but becomes molten at around 220-230°C. Due to its rigid molecular chains, the resin melt has high viscosity. PC has low water absorption and shrinkage, resulting in high dimensional accuracy and stability. However, it is susceptible to stress cracking, fatigue, and has poor solvent resistance and wear resistance.

PC exhibits significant cold-forming capabilities at room temperature due to its high impact toughness. Cold pressing, cold drawing, and cold rolling are possible processing methods. Extrusion-grade PC should have a molecular weight greater than 30,000, and the screw should have a gradual compression design with a length-to-diameter ratio of 1:18 to 1:24 and a compression ratio of 1:2.5. PC is available in various alloy types, combining its properties with other polymers to enhance material performance and reduce costs.

PET Polyethylene Terephthalate 

Typical applications:

Automotive industry (structural components like reflector housings, electrical components like headlamp reflectors, etc.), electrical components (motor housings, electrical connectors, relays, switches, microwave oven internal components). Industrial applications (pump housings, hand tools, etc.).

Chemical and physical properties:

PET has a glass transition temperature around 165°C, and its crystallization temperature range is 120 to 220°C. PET has strong hygroscopicity at high temperatures. Glass fiber-reinforced PET materials are prone to bending deformation at high temperatures. The crystallinity of PET can be enhanced by adding crystallization enhancers.

Transparent products processed with PET have glossiness and heat distortion temperature. Special additives such as mica can be added to PET to minimize bending deformation.

13. PETG - Polyethylene terephthalate glycol-modified Typical applications: Medical equipment (test tubes, reagent bottles, etc.), toys, displays, light covers, protective face shields, refrigerator trays, etc.

Chemical and physical properties: PETG is a transparent, amorphous material with a glass transition temperature of 88°C. It possesses transparency, high strength, and good flexibility.

PMMA - Polymethyl methacrylate 

Typical applications: 

Automotive industry (signal light equipment, dashboards, etc.), pharmaceutical industry (blood storage containers, etc.), industrial applications (optical discs, light diffusers), and consumer goods (beverage cups, stationery, etc.).

Chemical and physical properties: 

PMMA has excellent optical properties and resistance to weathering. It has high light transmittance of up to 92%. PMMA products have low birefringence, making them suitable for optical applications. PMMA also has good impact resistance.

POM - Polyoxymethylene 

Typical applications: POM is suitable for producing gears and bearings due to its low friction coefficient and excellent dimensional stability. It is also used in piping devices (valves, pump housings), lawn equipment, etc.

Chemical and physical properties: POM is a tough and elastic material, with good creep resistance and impact resistance even at low temperatures. It can be either homopolymer or copolymer. Both types are crystalline materials and have low moisture absorption. POM has a high degree of crystallinity, resulting in significant shrinkage of up to 2%-3.5%.

PP - Polypropylene 

Typical applications: Automotive industry (PP with metal additives for fenders, ventilation pipes, fans, etc.), medical equipment, appliances (dryer ventilation pipes, refrigerator door gaskets, etc.), consumer goods (lawn and garden equipment such as lawnmowers and sprinklers).

Chemical and physical properties: PP is a semi-crystalline material, harder and with a higher melting point than PE. Commercial PP materials often contain random copolymers with 1%-4% ethylene or block copolymers with higher ethylene content. PP has good chemical resistance but is susceptible to attack by aromatic and chlorinated hydrocarbons.

PPE - Polyphenylene Ether Typical applications: Electrical appliances like dishwasher, washing machine, etc., control housings, fiber optic connectors, etc.

Chemical and physical properties: Commercial PPE or PPO materials often contain other thermoplastic materials such as PS or PA. PPE/PPO mixtures have improved processing characteristics. PPE has good chemical and thermal stability, low water absorption, and excellent dimensional stability.

PS - Polystyrene Typical applications: Product packaging, household items, electrical components, toys, and entertainment products, as well as construction materials.

Chemical and physical properties: Most commercial PS is transparent and amorphous. It has good dimensional stability, thermal stability, optical transparency, and electrical insulation properties. PS is resistant to water and dilute inorganic acids but can be attacked by strong oxidizing acids like concentrated sulfuric acid.

PVC - Polyvinyl chloride 

Typical applications: 

Water supply pipes, household pipes, wall panels, commercial machine housings, electronic product packaging, medical devices, food packaging, etc.

Chemical and physical properties: 

Rigid PVC is one of the most widely used plastics. It is a non-crystalline material, and its properties can be modified by adding stabilizers, lubricants, processing aids, colorants, impact modifiers, and other additives. PVC is resistant to oxidation, reduction, and strong acids but can be corroded by concentrated oxidizing acids like concentrated sulfuric acid and concentrated nitric acid.

AS (SAN) - Acrylonitrile-Styrene copolymer transparent adhesive 

Typical applications: 

Electrical sockets, household goods (kitchen utensils, refrigerator devices, TV stands, cassette boxes, refrigerator trays, knobs, lamp accessories, decorations, stationery, etc.), automotive industry (headlamp housings, reflectors, dashboards, etc.), household items (cutlery, food knives, trays, cups, etc.), cosmetic packaging, instrument mirrors, packaging boxes, etc. It is widely used in industrial products resistant to oil, heat, and chemical substances, as well as instrument panels, instrument frames, covers, battery boxes, junction boxes, various switches, and buttons.

Chemical and physical properties: 

AS is a copolymer of acrylonitrile (A) and styrene (S). It has medium weather resistance, is not affected by high humidity, can withstand general oils, detergents, and mild alcohols, but has poor fatigue resistance. AS is a hard and transparent material. Styrene imparts hardness, transparency, and ease of processing to AS, while acrylonitrile provides chemical and thermal stability. AS can withstand loads, chemical reactions, heat deformation, and has good dimensional stability. Adding glass fiber additives to AS can increase its strength and heat deformation resistance while reducing its coefficient of thermal expansion. AS has a Vicat softening temperature of about 110°C and a flexural deformation temperature under load of about 100°C. Its shrinkage rate is approximately 0.3%-0.7%.

HIPS - High Impact Polystyrene

Typical applications: 

Packaging and disposable products, instruments, household appliances, toys and entertainment products, and the construction industry. Flame-retardant grades (UL V-0 and UL 5-V) and impact-resistant polystyrene are widely used in TV casings, commercial machines, and electrical products.

HIPS properties: 

HIPS is a modified material of PS, containing 5%-15% rubber components, which greatly increases its toughness (high-impact polystyrene). It comes in various grades, including flame retardant, stress crack resistant, high gloss, high impact strength, glass fiber reinforced, and low residual volatile content. Standard HIPS has a flexural strength of 13.8-55.1 MPa, a tensile strength of 13.8-41.4 MPa, and a fracture elongation of 15%-75%. It has a density of 1.035-1.04 g/ml and is non-transparent. HIPS has low water absorption and does not require pre-drying during processing.

PPO Polyphenylene Oxide 

Typical applications

PPO and MPPO are mainly used in electronics, automotive, household appliances, office equipment, and industrial machinery. MPPO has heat resistance, impact resistance, dimensional stability, scratch resistance, paintability, and electrical properties. It is used for making car dashboards, radiator grilles, speaker grilles, consoles, fuse boxes, relay boxes, connectors, wheel covers, connectors, etc. PPO is widely used in the electronics industry to manufacture connectors, coil winding shafts, switch relays, tuning devices, large electronic displays, variable capacitors, battery accessories, microphones, and other parts.

Used in household appliances such as television sets, cameras, videotapes, recorders, air conditioners, heaters, rice cookers, and other components. It can also be used in photocopiers, computer systems, printers, fax machines, and other external parts and components. Additionally, it can be used to manufacture casings and components for cameras, timers, water pumps, blowers, silent gears, pipes, valve bodies, surgical instruments, and disinfectors, among other medical device components.

Properties of PPO:

Polyphenylene ether is a polymer of 2,6-dimethyl-1,4-phenylene oxide, also known as polyphenyleneoxide (PPO), and modified PPO is PPO modified with polystyrene or other polymers, known as MPPO.

PPO (NORLY) is an excellent engineering plastic with comprehensive properties. It has higher hardness than PA, POM, and PC, high mechanical strength, good rigidity, excellent heat resistance (heat distortion temperature of 126°C), high dimensional stability (shrinkage rate of 0.6%), and low water absorption (less than 0.1%). However, it is not stable against ultraviolet radiation, has a higher cost, and is used in smaller quantities. PPO is non-toxic, transparent, and has a relatively low density. It exhibits excellent mechanical strength, stress relaxation resistance, creep resistance, heat resistance, water resistance, and resistance to steam.

PPO has good electrical properties over a wide temperature and frequency range, is not susceptible to hydrolysis, and has low molding shrinkage. It is flame-retardant with self-extinguishing properties and resistant to inorganic acids, alkalis, aromatic hydrocarbons, halogenated hydrocarbons, and oils. However, it is susceptible to swelling or stress cracking. The main disadvantage of PPO is its poor melt flowability, making processing and molding difficult. In practical applications, most of it is used as MPPO (PPO blends or alloys). By using PS-modified PPO, processing properties, stress crack resistance, and impact resistance can be significantly improved while reducing costs, albeit with a slight decrease in heat resistance and gloss.

Modified polymers include PS (including HIPS), PA, PTFE, PBT, PPS, various elastomers, and polysiloxanes. PS-modified PPO wax is the most widely used product, and MPPO is the most extensively used general engineering plastic alloy. Notable MPPO varieties include PPO/PS, PPO/PA/elastomer, and PPO/PBT elastomer alloys.