plastic

Plastic is the general term for a wide range of synthetic or semisynthetic polymerization products. They are composed of organic condensation or addition polymers and may contain other substances to improve performance or reduce costs. There are many natural polymers generally considered to be "plastics". Plastics can be formed into objects or films or fibers. Their name is derived from the malleability, or plasticity, of many of them

Polypropylene or polypropene (PP) is a thermoplastic polymer, made by the chemical industry and used in a wide variety of applications, including packaging, textiles (e.g., ropes, thermal underwear and carpets), stationery, plastic parts and reusable containers of various types, laboratory equipment, loudspeakers, automotive components, and polymer banknotes. An addition polymer made from the monomer propylene, it is rugged and unusually resistant to many chemical solvents, bases and acids. Its resin identification code is . Melt processing of polypropylene can be achieved via two general methods: 1) extrusion and 2) molding.

Common extrusion methods include production of melt blown and spun bond fibers to form long rolls for future conversion into a wide range of useful products such as face masks, filters, diapers and wipes.

The most common molding technique is that of injection molding. The types of molded parts made are almost limitless, but commonly include cups, cutlery, vials, caps, containers, housewares and automotive parts such as batteries. Blow molding and injection-stretch blow molding are techniques involving both extrusion and molding.

The large number of end use applications for PP are often possible because of the ability to tailor grades with specific molecular properties and additives during its manufacture. For example, antistatic additives can be added to help PP surfaces resist dust and dirt. Many physical finishing techniques can also be used on PP, such as machining. Surface treatments can be applied to PP parts in order to promote adhesion of printing ink and paints.

Polystyrene IPA: /ˌpɒliˈstaɪriːn/ (IUPAC Polyphenylethene) is an aromatic polymer made from the aromatic monomer styrene, a liquid hydrocarbon that is commercially manufactured from petroleum by the chemical industry. Polystyrene is a thermoplastic substance, normally existing in solid state at room temperature, but melting if heated (for molding or extrusion), and becoming solid again when cooling off.

Pure solid polystyrene is a colorless, hard plastic with limited flexibility. It can be cast into molds with fine detail. Polystyrene can be transparent or can be made to take on various colours. It is economical and is used for producing plastic model assembly kits, license plate frames, plastic cutlery, CD "jewel" cases, and many other objects where a fairly rigid, economical plastic is desired

Polyester (aka Terylene) is a category of polymers which contain the ester functional group in their main chain. Although there are many forms of polyesters, the term "polyester" is most commonly used to refer to polyethylene terephthalate (PET). Other forms of polyester include naturally occurring cutin of plant cuticles as well as synthetic polyesters such as polycarbonate and polybutyrate.

Polyester may be produced in numerous forms. For example, polyester as a thermoplastic may be heated and processed into different forms, e.g., fibers, sheets, and three-dimensional shapes. While combustible at high temperatures, polyester tends to shrink away from flames and self-extinguishes.

A polyurethane, commonly abbreviated PU, is any polymer consisting of a chain of organic units joined by urethane links. Polyurethane polymers are formed by reacting a monomer containing at least two isocyanate functional groups with another monomer containing at least two alcohol groups in the presence of a catalyst.

Polyurethane formulations cover an extremely wide range of stiffness, hardness, and densities. These materials include:

low density flexible foam used in upholstery and bedding,
low density rigid foam used for thermal insulation and e.g. automobile dashboards,
soft solid elastomers used for gel pads and print rollers, and
hard solid plastics used as electronic instrument bezels and structural parts.

Polyurethanes are widely used in high resiliency flexible foam seating, rigid foam insulation panels, microcellular foam seals and gaskets, durable elastomeric wheels and tires, electrical potting compounds, high performance adhesives and sealants, Spandex fibres, seals, gaskets, carpet underlay, and hard plastic parts.

Polyurethane products are often called "urethanes". They should not be confused with the specific substance urethane, also known as ethyl carbamate. Polyurethanes are not produced from ethyl carbamate, nor do they contain it.

Polyvinyl chloride, (IUPAC Polychloroethene) commonly abbreviated PVC, is a widely used thermoplastic polymer. In terms of revenue generated, it is one of the most valuable products of the chemical industry. Around the world, over 50% of PVC manufactured is used in construction. As a building material, PVC is cheap, durable, and easy to assemble. In recent years, PVC has been replacing traditional building materials such as wood, concrete and clay in many areas. Despite the fact that PVC production negatively affects the natural environment and human health, it is still widely used.[citation needed]

Polyvinyl chloride is used in a variety of applications. As a hard plastic, it is used as vinyl siding, magnetic stripe cards, window profiles, gramophone records (which is the source of the term vinyl records), pipe, plumbing and conduit fixtures. The material is often used in Plastic Pressure Pipe Systems for pipelines in the water and sewer industries because of its inexpensive nature and flexibility. PVC pipe plumbing is typically white, as opposed to ABS, which is commonly available in grey and black, as well as white. UPVC can sometimes be used as bulletproof glass for a cars window as it is very hard and thick.[citation needed]

It can be made softer and more flexible by the addition of plasticizers, the most widely-used being phthalates. In this form, it is used in clothing and upholstery, and to make flexible hoses and tubing, flooring, to roofing membranes, and electrical cable insulation.

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