Plastic is the general common term for a wide range of synthetic or semisynthetic organic Organic chemistry is a discipline within chemistry which involves the scientific study of the structure, properties, composition, reactions, and preparation of chemical compounds that contain carbon. These compounds may contain any number of other elements, including hydrogen, nitrogen, oxygen, the halogens as well as phosphorus, silicon and amorphous solid An "amorphous solid" is a solid in which there is no long-range order of the positions of the atoms. . Most classes of solid materials can be found or prepared in an amorphous form. For instance, common window glass is an amorphous solid, many polymers (such as polystyrene) are amorphous, and even foods such as cotton candy are amorphous[1] materials suitable for the manufacture of industrial products. Plastics are typically polymers A polymer is a large molecule (macromolecule) composed of repeating structural units typically connected by covalent chemical bonds. While polymer in popular usage suggests plastic, the term actually refers to a large class of natural and synthetic materials with a variety of properties of high molecular mass, and may contain other substances to improve performance and/or reduce costs.
The word derives from the Greek Greek , an independent branch of the Indo-European family of languages, is the language of the Greeks. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. In its ancient form, it is the language of classical ancient Greek literature and the New Testament of πλαστικός (plastikos) meaning fit for molding, and πλαστός (plastos) meaning molded.[2][3] It refers to their malleability, or plasticity In physics and materials science, plasticity describes the deformation of a material undergoing non-reversible changes of shape in response to applied forces. For example, a solid piece of metal or plastic being bent or pounded into a new shape displays plasticity as permanent changes occur within the material itself. By contrast, a permanent during manufacture, that allows them to be cast Casting is a manufacturing process by which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process. Casting materials are usually metals or various cold, pressed Death by crushing or pressing is a method of execution that has a long history during which the techniques used varied greatly from place to place. This form of execution is no longer sanctioned by any governing body, or extruded Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed or drawn through a die of the desired cross-section. The two main advantages of this process over other manufacturing processes is its ability to create very complex cross-sections and work materials that are brittle, because the material only into an enormous variety of shapes—such as films Artificial membrane also known as synthetic membrane is a syntheticly created membrane which is usually intended for separation purposes in laboratory or in industry. Synthetic membranes have been successfully used for small and large-scale industrial processes since the middle of twentieth century. A wide variety of synthetic membranes is known, fibers Synthetic fibers are the result of extensive research by scientists to improve upon naturally occurring animal and plant. In general, synthetic fibers are created by forcing, usually through extrusion, fiber forming materials through holes into the air, forming a thread. Before synthetic fibers were developed, artificially manufactured fibers were, plates, tubes, bottles, boxes, and much more.
The common word plastic should not be confused with the technical adjective plastic, which is applied to any material which undergoes a permanent change of shape (plastic deformation In physics and materials science, plasticity describes the deformation of a material undergoing non-reversible changes of shape in response to applied forces. For example, a solid piece of metal or plastic being bent or pounded into a new shape displays plasticity as permanent changes occur within the material itself. By contrast, a permanent) when strained beyond a certain point. Aluminium, for instance, is plastic in this sense, but not a plastic in the common sense; in contrast, in their finished forms, some plastics will break before deforming and therefore are not plastic in the technical sense.
There are two types of plastics: thermoplastics A thermoplastic is a polymer that turns to a liquid when heated and freezes to a very glassy state when cooled sufficiently. Most thermoplastics are high-molecular-weight polymers whose chains associate through weak Van der Waals forces ; stronger dipole-dipole interactions and hydrogen bonding (nylon); or even stacking of aromatic rings ( and thermosets Thermosetting plastics are polymer materials that irreversibly cure. The cure may be done through heat (generally above 200 degrees Celsius), through a chemical reaction (two-part epoxy, for example), or irradiation such as electron beam processing. Thermoplastics will soften and melt if enough heat is applied; examples are polyethylene Polyethylene or polythene (IUPAC name polyethene or poly) is the most widely used plastic, with an annual production of approximately 80 million metric tons. Its primary use is within packaging (notably the plastic shopping bag), polystyrene Polystyrene (IUPAC Poly(1-phenylethane-1,2-diyl)), sometimes abbreviated PS, 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 one of the most widely used kinds of plastic, polyvinyl chloride Polyvinyl chloride, (IUPAC Poly) commonly abbreviated PVC, is the third most widely used thermoplastic polymer after polyethylene and polypropylene.[citation needed] 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 and polytetrafluoroethylene In chemistry, polytetrafluoroethylene is a synthetic fluoropolymer of tetrafluoroethylene which finds numerous applications. PTFE is most well known by the DuPont brand name Teflon (PTFE)[4] . Thermosets do not soften or melt no matter how much heat is applied.
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San Jose Mercury News
Clerks at Andronico's, Safeway, JJ&F Food Store and Mollie Stone's said Wednesday they are no longer providing plastic bags at the checkout counter. ...
No Plastic in Palo Alto KCBS
Plastic bags shelved at supermarkets Palo Alto Online
Another California City to Ban Plastic Bags PublicCEO.com (blog)
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Ocean s 13 Star Ellen Barkin has mixed feelings about plastic surgery While the 53 year old actress thinks cosmetic surgery is a dangerous trend for society she still regularly treats
