As we all know, there are many types of materials that may be used in the injection molding process. Most polymers may be used, including all thermoplastics, some thermosets, and some elastomers. When these materials are used in the injection molding process, their raw form is usually small pellets or a fine powder.
Also, colorants may be added in the process to control the color of the final part. The selection of a material for creating injection molded parts is not solely based upon the desired characteristics of the final part.
While each material has different properties that will affect the strength and function of the final part, these properties also dictate the parameters used in processing these materials.
Each material requires a different set of processing parameters in the injection molding process, including the injection temperature, injection pressure, mold temperature, ejection temperature, and cycle time. A comparison of some commonly used materials is shown below:
Material name | Abbreviation | Trade names | Description | Applications |
Acetal | POM | Celcon, Delrin, Hostaform, Lucel | Strong, rigid, excellent fatigue resistance, excellent creep resistance, chemical resistance, moisture resistance, naturally opaque white, low/medium cost | Bearings, cams, gears, handles, plumbing components, rollers, rotors, slide guides, valves |
Acrylic | PMMA | Diakon, Oroglas, Lucite, Plexiglas | Rigid, brittle, scratch resistant, transparent, optical clarity, low/medium cost | Display stands, knobs, lenses, light housings, panels, reflectors, signs, shelves, trays |
Acrylonitrile Butadiene Styrene | ABS | Cycolac, Magnum, Novodur, Terluran | Strong, flexible, low mold shrinkage (tight tolerances), chemical resistance, electroplating capability, naturally opaque, low/medium cost | Automotive (consoles, panels, trim, vents), boxes, gauges, housings, inhalors, toys |
Cellulose Acetate | CA | Dexel, Cellidor, Setilithe | Tough, transparent, high cost | Handles, eyeglass frames |
Polyamide 6 (Nylon) | PA6 | Akulon, Ultramid, Grilon | High strength, fatigue resistance, chemical resistance, low creep, low friction, almost opaque/white, medium/high cost | Bearings, bushings, gears, rollers, wheels |
Polyamide 6/6 (Nylon) | PA6/6 | Kopa, Zytel, Radilon | High strength, fatigue resistance, chemical resistance, low creep, low friction, almost opaque/white, medium/high cost | Handles, levers, small housings, zip ties |
Polyamide 11+12 (Nylon) | PA11+12 | Rilsan, Grilamid | High strength, fatigue resistance, chemical resistance, low creep, low friction, almost opaque to clear, very high cost | Air filters, eyeglass frames, safety masks |
Polycarbonate | PC | Calibre, Lexan, Makrolon | Very tough, temperature resistance, dimensional stability, transparent, high cost | Automotive (panels, lenses, consoles), bottles, containers, housings, light covers, reflectors, safety helmets and shields |
Polyester - Thermoplastic | PBT, PET | Celanex, Crastin, Lupox, Rynite, Valox | Rigid, heat resistance, chemical resistance, medium/high cost | Automotive (filters, handles, pumps), bearings, cams, electrical components (connectors, sensors), gears, housings, rollers, switches, valves |
Polyether Sulphone | PES | Victrex, Udel | Tough, very high chemical resistance, clear, very high cost | Valves |
Polyetheretherketone | PEEKEEK | Strong, thermal stability, chemical resistance, abrasion resistance, low moisture absorption | Aircraft components, electrical connectors, pump impellers, seals | |
Polyetherimide | PEI | Ultem | Heat resistance, flame resistance, transparent (amber color) | Electrical components (connectors, boards, switches), covers, sheilds, surgical tools |
Polyethylene - Low Density | LDPE | Alkathene, Escorene, Novex | Lightweight, tough and flexible, excellent chemical resistance, natural waxy appearance, low cost | Kitchenware, housings, covers, and containers |
Polyethylene - High Density | HDPE | Eraclene, Hostalen, Stamylan | Tough and stiff, excellent chemical resistance, natural waxy appearance, low cost | Chair seats, housings, covers, and containers |
Polyphenylene Oxide | PPO | Noryl, Thermocomp, Vamporan | Tough, heat resistance, flame resistance, dimensional stability, low water absorption, electroplating capability, high cost | Automotive (housings, panels), electrical components, housings, plumbing components |
Polyphenylene Sulphide | PPS | Ryton, Fortron | Very high strength, heat resistance, brown, very high cost | Bearings, covers, fuel system components, guides, switches, and shields |
Polypropylene | PP | Novolen, Appryl, Escorene | Lightweight, heat resistance, high chemical resistance, scratch resistance, natural waxy appearance, tough and stiff, low cost. | Automotive (bumpers, covers, trim), bottles, caps, crates, handles, housings |
Polystyrene - General purpose | GPPS | Lacqrene, Styron, Solarene | Brittle, transparent, low cost | Cosmetics packaging, pens |
Polystyrene - High impact | HIPS | Polystyrol, Kostil, Polystar | Impact strength, rigidity, toughness, dimensional stability, naturally translucent, low cost | Electronic housings, food containers, toys |
Polyvinyl Chloride - Plasticised | PVC | Welvic, Varlan | Tough, flexible, flame resistance, transparent or opaque, low cost | Electrical insulation, housewares, medical tubing, shoe soles, toys |
Polyvinyl Chloride - Rigid | UPVC | Polycol, Trosiplast | Tough, flexible, flame resistance, transparent or opaque, low cost | Outdoor applications (drains, fittings, gutters) |
Styrene Acrylonitrile | SAN | Luran, Arpylene, Starex | Stiff, brittle, chemical resistance, heat resistance, hydrolytically stable, transparent, low cost | Housewares, knobs, syringes |
Thermoplastic Elastomer/Rubber | TPE/R | Hytrel, Santoprene, Sarlink | Tough, flexible, high cost | Bushings, electrical components, seals, washers |
The material cost is determined by the weight of material that is required and the unit price of that material. The weight of material is clearly a result of the part volume and material density; however, the part's maximum wall thickness can also play a role. The weight of material that is required includes the material that fills the channels of the mold. The size of those channels, and hence the amount of material, is largely determined by the thickness of the part.
TEAM MFG is a rapid manufacturing company who specializes in ODM and OEM. We provide leading Injection molding source for prototyping and on-demand manufacturing. We are the World's fastest Injection molding company. Get an online quote today.
