Plastic materials composed of natural, organic, and synthetic monomers can be organized into two large groups: thermoplastics and thermosetting plastics.
Of the two, thermoplastics are the most widely used. This is because they are easy to work with; when heated, they become pliable and when cooled, they become rigid again. The process of heating and shaping a thermoplastic can be performed over and over again; the same material may be recreated many times.
Thermoplastics may be acquired as preformed stock shapes, or in resin form, from which shapes may be made. The one drawback of thermoplastic products is that, if a user places the product in an extremely cold environment, the thermoplastic may become glass-like and runs the risk of fracture.
Thermosetting plastics, on the other hand, do quite well with the cold, and are actually generally stronger than thermoplastics. They, unfortunately do not do so well in the face of high heat, which degrades them chemically, and once they have been cured, they cannot be remolded. Instead, manufacturers must acquire new material, which is available only as non-flowing mass premixed blends or two-part liquid resins.
Thermosetting plastics may be cured via air setting, anaerobic, cross-linking, hot melt, room temperature curing, or vulcanizing methods. Examples of thermosetting plastics include polyurethane, Bakelite, Duroplast, epoxy resin, cyanate esters, and polyester resins. Read More…
Polystyrene is more commonly known by its trademarked name Styrofoam. Styrofoam, in its official form, is composed of close-celled extruded polystyrene foam, mostly used for thermal insulation and craft applications. However, in North America, styrofoam has become the generic name for any kind of expanded polystyrene foam. The latter styrofoam is the material used to make coolers, disposable coffee cups, and cushioning beads or pellets for packaging.
Polyethylene is the most popular member of the plastics family, with an average annual global production of 80 millions tons. Most of its applications are related to packaging; is used to make products such as shampoo bottles, milk cartons, plastic bags, plastic films, filters, and geomembranes. In addition, polyethylene is used to fabricate artificial knees.
Polypropylene is a thermoplastic that is more resistant to solvents, chemicals, acids, and bases than most plastics. As such, it is used to make automotive components, textiles such as diapers, thermal underwear, sanitary pads, carpet, and some types of rope, stationary, laboratory equipment, and more.
A common synthetic plastic is Delrin, which is also known by the names polyoxymethylene (POM), polyformaldehyde, polyacetal, and acetal. Delrin is characterized by extremely high strength, rigidity, and hardness. With these qualities, it is often used as a metal substitute and is used to fabricate precision automotive and construction parts, as well products like small gear wheels, ball bearings, eyeglass frames, fasteners and lock system components.
Acrylic, or poly(methyl methacrylate), more commonly known as Plexiglass, is a transparent thermoplastic frequently used in sheet form as a glass substitute. Shatter-proof, acrylic plastic, also known as acrylic glass, is used to create many necessarily strong products, such as bullet-proof security barriers and glass, skylights, rear lights and instrument clusters for automobiles, bathtubs, signs and displays, and LCD screens.
Plastics in the polycarbonate family are simply thermoplastic polymers that contain carbonate groups in their chemical structures. Generically, a plastic in this group can simply be called polycarbonate. Polycarbonate is known to have good heat and flame resistance and to be a good electrical insulator, and manufacturers mainly use it to produce electrical components, construction materials, aircraft and automobile parts, security components and personal security apparel, including riot gear, sunglasses, swim goggles, scuba masks, and safety glasses.
PVC, or polyvinyl chloride, is the third-most widely produced synthetic plastic polymer in the world. It is available in two forms: flexible and rigid, both of which are very popular in their own right. Flexible PVC, which is made so through the addition of plasticizers, is often used in electrical cable insulation, plumbing, imitation leather, inflatables, and in many applications as a rubber substitute. Rigid PVC (RPVC) is used to create bottles, non-food packaging, plastic cards, construction components like pipes, and door and window profiles.
Plastic materials are available in a number of stock forms, such as films, rods, sheets, pipes, and profiles. These stock shapes may serve as a finished product, or they may go on to receive more processing. Manufacturers can produce stock forms and other plastic products in a number of ways, usually through some type of extrusion or injection molding.
Plastic fabrication processes that manufacturers may use include: blown film extrusion (used to fabricate plastic film), foam extrusion, pultrusion, precision plastic machining, pressure forming, vacuum forming, thermoforming, welding, grinding and casting. When forming, manufacturers may use pure resins or they may combine the resins with additives such as fillers, heat stabilizers, lubricants, or plasticizers, as needed.
Additives may be used to change any number of plastic material properties, including density, color, structural integrity, corrosion resistance, heat resistance, strength, and working temperature range. If the right processes are implemented and implemented well, plastic materials can be turned into countless invaluable products in every industry, from aerospace, to food processing, to automotive, to water treatment.