Plastic 1

Plastic

Household items made of various types of plastic

A plastic material is any of a wide range ofsynthetic or semi-synthetic organic solidsused in the manufacture of industrialproducts. Plastics are typically polymers ofhigh molecular mass, and may contain othersubstances to improve performance and/orreduce costs. Monomers of plastic are eithernatural or synthetic organic compounds.

The word plastic is derived from the Greekπλαστικός (plastikos) meaning capable ofbeing shaped or molded, from πλαστός(plastos) meaning molded.[1] [2] It refers totheir malleability, or plasticity duringmanufacture, that allows them to be cast,pressed, or extruded into a variety of shapes—such as films, fibers, plates, tubes, bottles, boxes, and much more.

The common word plastic should not be confused with the technical adjective plastic, which is applied to anymaterial which undergoes a permanent change of shape (plastic deformation) when strained beyond a certain point.Aluminum which is stamped or forged, for instance, exhibits plasticity in this sense, but is not plastic in the commonsense; in contrast, in their finished forms, some plastics will break before deforming and therefore are not plastic inthe technical sense.There are two types of plastics: thermoplastics and thermosetting polymers. Thermoplastics are the plastics that don'tundergo chemical change in their composition when heated and can be moulded again and again; examples arepolyethylene, polystyrene, polyvinyl chloride and polytetrafluoroethylene (PTFE).[3] Thermosets can melt and takeshape once; after they have solidified, they stay solid.The raw materials needed to make most plastics come from petroleum and natural gas.[4]

OverviewPlastics can be classified by chemical structure, namely the molecular units that make up the polymer's backbone andside chains. Some important groups in these classifications are the acrylics, polyesters, silicones, polyurethanes, andhalogenated plastics. Plastics can also be classified by the chemical process used in their synthesis, such ascondensation, polyaddition, and cross-linking.[5]

Other classifications are based on qualities that are relevant for manufacturing or product design. Examples of suchclasses are the thermoplastic and thermoset, elastomer, structural, biodegradable, and electrically conductive. Plasticscan also be classified by various physical properties, such as density, tensile strength, glass transition temperature,and resistance to various chemical products.Due to their relatively low cost, ease of manufacture, versatility, and imperviousness to water, plastics are used in anenormous and expanding range of products, from paper clips to spaceships. They have already displaced manytraditional materials, such as wood; stone; horn and bone; leather; paper; metal; glass; and ceramic, in most of theirformer uses.The use of plastics is constrained chiefly by their organic chemistry, which seriously limits their hardness, density, and their ability to resist heat, organic solvents, oxidation, and ionizing radiation. In particular, most plastics will melt or decompose when heated to a few hundred degrees celsius.[6] While plastics can be made electrically

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conductive, with the conductivity of up to 80 kS/cm in stretch-oriented polyacetylene,[7] [8] [9] [10] they are still nomatch for most metals like copper which have conductivities of several hundreds kS/cm. Plastics are still tooexpensive to replace wood, concrete and ceramic in bulky items like ordinary buildings, bridges, dams, pavement,and railroad ties.

Chemical structureCommon thermoplastics range from 20,000 to 500,000 amu, while thermosets are assumed to have infinitemolecular weight. These chains are made up of many repeating molecular units, known as repeat units, derived frommonomers; each polymer chain will have several thousand repeating units. The vast majority of plastics arecomposed of polymers of carbon and hydrogen alone or with oxygen, nitrogen, chlorine or sulfur in the backbone.(Some of commercial interests are silicon based.) The backbone is that part of the chain on the main "path" linking alarge number of repeat units together. To customize the properties of a plastic, different molecular groups "hang"from the backbone (usually they are "hung" as part of the monomers before linking monomers together to form thepolymer chain). This fine tuning of the properties of the polymer by repeating unit's molecular structure has allowedplastics to become such an indispensable part of twenty first-century world.Some plastics are partially crystalline and partially amorphous in molecular structure, giving them both a meltingpoint (the temperature at which the attractive intermolecular forces are overcome) and one or more glass transitions(temperatures above which the extent of localized molecular flexibility is substantially increased). The so-calledsemi-crystalline plastics include polyethylene, polypropylene, poly (vinyl chloride), polyamides (nylons), polyestersand some polyurethanes. Many plastics are completely amorphous, such as polystyrene and its copolymers, poly(methyl methacrylate), and all thermosets.

Molded plastic food replicas on display outside a restaurant in Japan

Families

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Plastics families

Amorphous Semi-crystalline

Ultra polymers PI, SRP, TPI, PAI, HTS PFSA, High performancepolymers

PPSU, PEI,PESU, PSU

Fluoropolymers: LCP,PARA, HPN, PPS, PPA

Otherpolyamides

Mid rangepolymers

PC, PPC, COC, PMMA,ABS, PVC Alloys

PEX, PVDC, PBT, PET, POM,PA 6,6, UHMWPE

Commoditypolymers

PS, PVC PP, HDPE, LDPE

HistoryThe first human-made plastic was invented by Alexander Parkes in 1855;[11] he called this plastic Parkesine (latercalled celluloid). It was unveiled at the 1862 Great International Exhibition in London.[12] The development ofplastics has come from the use of natural plastic materials (e.g., chewing gum, shellac) to the use of chemicallymodified natural materials (e.g., rubber, nitrocellulose, collagen, galalite) and finally to completely syntheticmolecules (e.g., bakelite, epoxy, polyvinyl chloride, polyethylene). In 1866, Parkes formed the Parkesine Companyto mass produce the material. The company, however, failed due to poor product quality as Parkes tried to reducecosts. Parkesine's successors were Xylonite, produced by Daniel Spill (an associate of Parkes), and Celluloid fromJohn Wesley Hyatt. Parkesine was made from cellulose treated with nitric acid and a solvent. The generic name ofParkesine is pyroxylin, or Celluloid. Parkesine is often synthetic ivory. The Parkesine company ceased trading in1868. Pictures of Parkesine are held by the Plastics Historical Society of London. There is a plaque on the wall of thesite of the Parkesine Works.[13]

Types

Cellulose-based plasticsParkes developed a synthetic replacement for ivory which he marketed under the trade name Parkesine, and whichwon a bronze medal at the 1862 World's fair in London. Parkesine was made from cellulose (the major component ofplant cell walls) treated with nitric acid and a solvent. The output of the process (commonly known as cellulosenitrate or pyroxilin) could be dissolved in alcohol and hardened into a transparent and elastic material that could bemolded when heated.[14] By incorporating pigments into the product, it could be made to resemble ivory.Bois Durci is a plastic molding material based on cellulose. It was patented in Paris by Lepage in 1855. It is madefrom finely ground wood flour mixed with a binder, either egg or blood albumen, or gelatine. The wood is probablyeither ebony or rose wood, which gives a black or brown resin. The mixture is dried and ground into a fine powder.The powder is placed in a steel mold and compressed in a powerful hydraulic press while being heated by steam. Thefinal product has a highly polished finish imparted by the surface of the steel mold.

BakeliteThe first so called plastic based on a synthetic polymer was made from phenol and formaldehyde, with the first viable and cheap synthesis methods invented in 1907, by Leo Hendrik Baekeland, a Belgian-born American living in New York state. Baekeland was searching for an insulating shellac to coat wires in electric motors and generators. He found that mixtures of phenol (C6H5OH) and formaldehyde (HCOH) formed a sticky mass when mixed together and heated, and the mass became extremely hard if allowed to cool. He continued his investigations and found that the material could be mixed with wood flour, asbestos, or slate dust to create "composite" materials with different

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properties. Most of these compositions were strong and fire resistant. The only problem was that the material tendedto foam during synthesis, and the resulting product was of unacceptable quality.Baekeland built pressure vessels to force out the bubbles and provide a smooth, uniform product. He publiclyannounced his discovery in 1912, naming it bakelite. It was originally used for electrical and mechanical parts,finally coming into widespread use in consumer goods in the 1920s. When the Bakelite patent expired in 1930, theCatalin Corporation acquired the patent and began manufacturing Catalin plastic using a different process thatallowed a wider range of coloring.Bakelite was the first true plastic. It was a purely synthetic material, not based on any material or even moleculefound in nature. It was also the first thermosetting plastic. Conventional thermoplastics can be molded and thenmelted again, but thermoset plastics form bonds between polymers strands when cured, creating a tangled matrix thatcannot be undone without destroying the plastic. Thermoset plastics are tough and temperature resistant.Bakelite was cheap, strong, and durable. It was molded into thousands of forms, such as cases for radios, telephonesand clocks, and billiard balls.Phenol-based ("Phenolic") plastics have been largely replaced by cheaper and less brittle plastics, but they are stillused in applications requiring their insulating and heat-resistant properties. For example, some electronic circuitboards are made of sheets of paper or cloth impregnated with phenolic resin.

Polystyrene and Polyvinyl Chloride

Plastic piping and firestops being installed inOntario. Certain plastic pipes can be used in some

non-combustible buildings, provided they arefirestopped properly and that the flame spreadratings comply with the local building code.

After the First World War, improvements in chemical technology ledto an explosion in new forms of plastics. Among the earliest examplesin the wave of new plastics were polystyrene (PS) and polyvinylchloride (PVC), developed by IG Farben of Germany.

Polystyrene is a rigid, brittle, inexpensive plastic that has been used tomake plastic model kits and similar knick-knacks. It would also be thebasis for one of the most popular "foamed" plastics, under the namestyrene foam or Styrofoam. Foam plastics can be synthesized in an"open cell" form, in which the foam bubbles are interconnected, as inan absorbent sponge, and "closed cell", in which all the bubbles aredistinct, like tiny balloons, as in gas-filled foam insulation and flotationdevices. In the late 1950s, high impact styrene was introduced, whichwas not brittle. It finds much current use as the substance of toyfigurines and novelties.

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Polyvinyl Chloride (PVC, commonly called "vinyl")[15] has side chains incorporating chlorine atoms, which formstrong bonds. PVC in its normal form is stiff, strong, heat and weather resistant, and is now used for makingplumbing, gutters, house siding, enclosures for computers and other electronics gear. PVC can also be softened withchemical processing, and in this form it is now used for shrink-wrap, food packaging, and rain gear.

All PVC polymers are degraded by heat and light. When this happens, hydrogen chloride is released into theatmosphere and oxidation of the compound occurs.[16] Because hydrogen chloride readily combines with watervapor in the air to form hydrochloric acid,[17] polyvinyl chloride is not recommended for long-term archival storageof silver, photographic film or paper (mylar is preferable).[18]

NylonThe real star of the plastics industry in the 1930s was polyamide (PA), far better known by its trade name nylon.Nylon was the first purely synthetic fiber, introduced by DuPont Corporation at the 1939 World's Fair in New YorkCity.In 1927, DuPont had begun a secret development project designated Fiber66, under the direction of Harvard chemistWallace Carothers and chemistry department director Elmer Keiser Bolton. Carothers had been hired to performpure research, and he worked to understand the new materials' molecular structure and physical properties. He tooksome of the first steps in the molecular design of the materials.His work led to the discovery of synthetic nylon fiber, which was very strong but also very flexible. The firstapplication was for bristles for toothbrushes. However, Du Pont's real target was silk, particularly silk stockings.Carothers and his team synthesized a number of different polyamides including polyamide 6.6 and 4.6, as well aspolyesters.[19]

General condensation polymerization reaction for nylon

It took DuPont twelve years and US$27 million to refine nylon, and to synthesize and develop the industrialprocesses for bulk manufacture. With such a major investment, it was no surprise that Du Pont spared little expenseto promote nylon after its introduction, creating a public sensation, or "nylon mania".

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Nylon mania came to an abrupt stop at the end of 1941 when the USA entered World War II. The productioncapacity that had been built up to produce nylon stockings, or just nylons, for American women was taken over tomanufacture vast numbers of parachutes for fliers and paratroopers. After the war ended, DuPont went back toselling nylon to the public, engaging in another promotional campaign in 1946 that resulted in an even bigger craze,triggering the so called nylon riots.Subsequently polyamides 6, 10, 11, and 12 have been developed based on monomers which are ring compounds; e.g.caprolactam. Nylon 66 is a material manufactured by condensation polymerization.Nylons still remain important plastics, and not just for use in fabrics. In its bulk form it is very wear resistant,particularly if oil-impregnated, and so is used to build gears, plain bearings, and because of good heat-resistance,increasingly for under-the-hood applications in cars, and other mechanical parts.

RubberNatural rubber is an elastomer (an elastic hydrocarbon polymer) that was originally derived from latex, a milkycolloidal suspension found in the sap of some plants. It is useful directly in this form (indeed, the first appearance ofrubber in Europe is cloth waterproofed with unvulcanized latex from Brazil) but, later, in 1839, Charles Goodyearinvented vulcanized rubber; this a form of natural rubber heated with, mostly, sulfur forming cross-links betweenpolymer chains (vulcanization), improving elasticity and durability.

Synthetic rubberThe first fully synthetic rubber was synthesized by Sergei Lebedev in 1910. In World War II, supply blockades ofnatural rubber from South East Asia caused a boom in development of synthetic rubber, notably styrene-butadienerubber. In 1941, annual production of synthetic rubber in the U.S. was only 231 tonnes which increased to 840,000tonnes in 1945. In the space race and nuclear arms race, Caltech researchers experimented with using syntheticrubbers for solid fuel for rockets. Ultimately, all large military rockets and missiles would use synthetic rubber basedsolid fuels, and they would also play a significant part in the civilian space effort.

ToxicityDue to their insolubility in water and relative chemical inertness, pure plastics generally have low toxicity in theirfinished state, and will pass through the digestive system with no ill effect (other than mechanical damage orobstruction). However, plastics often contain a variety of toxic additives. For example, plasticizers like adipates andphthalates are often added to brittle plastics like polyvinyl chloride (PVC) to make them pliable enough for use infood packaging, toys and teethers, tubing, shower curtains and other items. Traces of these chemicals can leach outof the plastic when it comes into contact with food. Out of these concerns, the European Union has banned the use ofDEHP (di-2-ethylhexyl phthalate), the most widely used plasticizer in PVC. Some compounds leaching frompolystyrene food containers have been found to interfere with hormone functions and are suspected humancarcinogens.[20]

Moreover, while the finished plastic may be non-toxic, the monomers used in its manufacture may be toxic; andsmall amounts of those chemicals may remain trapped in the product. The World Health Organization's InternationalAgency for Research on Cancer (IARC) has recognized the chemical used to make PVC, vinyl chloride, as a knownhuman carcinogen.[20] Some polymers may also decompose into the monomers or other toxic substances whenheated.The primary building block of polycarbonates, bisphenol A (BPA), is an estrogen-like endocrine disruptor that may leach into food.[20] Research in Environmental Health Perspectives finds that BPA leached from the lining of tin cans, dental sealants and polycarbonate bottles can increase body weight of lab animals' offspring.[21] A more recent animal study suggests that even low-level exposure to BPA results in insulin resistance, which can lead to

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inflammation and heart disease.[22]

As of January 2010, the LA Times newspaper reports that the United States FDA is spending $30 million toinvestigate suspicious indications of BPA being linked to cancer.[23]

Bis(2-ethylhexyl) adipate, present in plastic wrap based on PVC, is also of concern, as are the volatile organiccompounds present in new car smell.The European Union has a permanent ban on the use of phthalates in toys. In 2009, the United States governmentbanned certain types of phthalates commonly used in plastic.[24]

Environmental issuesPlastics are durable and degrade very slowly; the molecular bonds that make plastic so durable make it equallyresistant to natural processes of degradation. Since the 1950s, one billion tons of plastic have been discarded andmay persist for hundreds or even thousands of years.[25] In some cases, burning plastic can release toxic fumes.Burning the plastic polyvinyl chloride (PVC) may create dioxin.[26] Also, the manufacturing of plastics often createslarge quantities of chemical pollutants.Prior to the ban on the use of CFCs in extrusion of polystyrene (and general use, except in life-critical firesuppression systems; see Montreal Protocol), the production of polystyrene contributed to the depletion of the ozonelayer; however, non-CFCs are currently used in the extrusion process.By 1995, plastic recycling programs were common in the United States and elsewhere. Thermoplastics can beremelted and reused, and thermoset plastics can be ground up and used as filler, though the purity of the materialtends to degrade with each reuse cycle. There are methods by which plastics can be broken back down to a feedstockstate.To assist recycling of disposable items, the Plastic Bottle Institute of the Society of the Plastics Industry devised anow-familiar scheme to mark plastic bottles by plastic type. A plastic container using this scheme is marked with atriangle of three "chasing arrows", which encloses a number giving the plastic type:

Plastics type marks: the resin identification code1. PET (PETE), polyethylene terephthalate2. HDPE, high-density polyethylene3. PVC, polyvinyl chloride4. LDPE, low-density polyethylene,5. PP, polypropylene6. PS, polystyrene7. Other types of plastics (see list, below)Unfortunately, recycling of plastics has proven to be a difficult process. The biggest problem is that it is difficult toautomate the sorting of plastic wastes, making it labor intensive. Typically, workers sort the plastic by looking at theresin identification code, although common containers like soda bottles can be sorted from memory. Typically, thecaps for PETE bottles are made from a different kind of plastic which is not recyclable, which presents additionalproblems to the automated sorting process. Other recyclable materials such as metals are easier to processmechanically. However, new processes of mechanical sorting are being developed to increase capacity andefficiency of plastic recycling.While containers are usually made from a single type and color of plastic, making them relatively easy to be sorted, a consumer product like a cellular phone may have many small parts consisting of over a dozen different types and colors of plastics. In such cases, the resources it would take to separate the plastics far exceed their value and the

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item is discarded. However, developments are taking place in the field of active disassembly, which may result inmore consumer product components being re-used or recycled. Recycling certain types of plastics can beunprofitable, as well. For example, polystyrene is rarely recycled because it is usually not cost effective. Theseunrecycled wastes are typically disposed of in landfills, incinerated or used to produce electricity at waste-to-energyplants.

Biodegradable (compostable) plasticsResearch has been done on biodegradable plastics that break down with exposure to sunlight (e.g., ultra-violetradiation), water or dampness, bacteria, enzymes, wind abrasion and some instances rodent pest or insect attack arealso included as forms of biodegradation or environmental degradation. It is clear some of these modes ofdegradation will only work if the plastic is exposed at the surface, while other modes will only be effective if certainconditions exist in landfill or composting systems. Starch powder has been mixed with plastic as a filler to allow it todegrade more easily, but it still does not lead to complete breakdown of the plastic. Some researchers have actuallygenetically engineered bacteria that synthesize a completely biodegradable plastic, but this material, such as Biopol,is expensive at present.[27] The German chemical company BASF makes Ecoflex, a fully biodegradable polyester forfood packaging applications.

BioplasticsSome plastics can be obtained from biomass, including:• from pea starch film with trigger biodegradation properties for agricultural applications (TRIGGER).[28]

• from biopetroleum.[29]

Oxo-biodegradableOxo-biodegradable (OBD) plastic is polyolefin plastic to which has been added very small (catalytic) amounts ofmetal salts. As long as the plastic has access to oxygen (as in a littered state), these additives catalyze the naturaldegradation process to speed it up so that the OBD plastic will degrade when subject to environmental conditions.Once degraded to a small enough particle they can interact with biological processes to produce to water, carbondioxide and biomass. The process is shortened from hundreds of years to months for degradation and thereafterbiodegradation depends on the micro-organisms in the environment. Typically this process is not fast enough to meetASTM D6400 standards for definition as compostable plastics.

Price, environment, and the futureThe biggest threat to the conventional plastics industry is most likely to be environmental concerns, including therelease of toxic pollutants, greenhouse gas, litter, biodegradable and non-biodegradable landfill impact as a result ofthe production and disposal of petroleum and petroleum-based plastics. Of particular concern has been the recentaccumulation of enormous quantities of plastic trash in ocean gyres.For decades one of the great appeals of plastics has been their low price. Yet in recent years the cost of plastics hasbeen rising dramatically. A major cause is the sharply rising cost of petroleum, the raw material that is chemicallyaltered to form commercial plastics.With some observers suggesting that future oil reserves are uncertain, the price of petroleum may increase further.Therefore, alternatives are being sought. Oil shale and tar oil are alternatives for plastic production but areexpensive. Scientists are seeking cheaper and better alternatives to petroleum-based plastics, and many candidatesare in laboratories all over the world. One promising alternative may be fructose.[30]

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Factory in a boxWith 3D images from the PC with special software, we may produce our 3D object plastic up to 6x6x7 inches withABS, HDPE or Corn-based biodegradable plastic material. The machine heats strands of plastic to 200 Celsius andbuilding up 3D objects layer by layer.[31]

Common plastics and uses

A chair made with a polypropylene seat

• Polyester (PES) - Fibers, textiles.• Polyethylene terephthalate (PET) - Carbonated drinks bottles,

peanut butter jars, plastic film, microwavable packaging.• Polyethylene (PE) - Wide range of inexpensive uses including

supermarket bags, plastic bottles.• High-density polyethylene - Detergent bottles and milk jugs.• Polyvinyl chloride (PVC) - Plumbing pipes and guttering, shower

curtains, window frames, flooring.• Polyvinylidene chloride (PVDC) (Saran) - Food packaging.• Low-density polyethylene (LDPE) - Outdoor furniture, siding, floor

tiles, shower curtains, clamshell packaging.• Polypropylene (PP) - Bottle caps, drinking straws, yogurt

containers, appliances, car fenders (bumpers), plastic pressure pipesystems.

• Polystyrene (PS) - Packaging foam/"peanuts", food containers,plastic tableware, disposable cups, plates, cutlery, CD and cassetteboxes.

• High impact polystyrene (HIPS) -: Refrigerator liners, foodpackaging, vending cups.

• Polyamides (PA) (Nylons) - Fibers, toothbrush bristles, fishing line, under-the-hood car engine moldings.• Acrylonitrile butadiene styrene (ABS) - Electronic equipment cases (e.g., computer monitors, printers,

keyboards), drainage pipe.• Polycarbonate (PC) - Compact discs, eyeglasses, riot shields, security windows, traffic lights, lenses.• Polycarbonate/Acrylonitrile Butadiene Styrene (PC/ABS) - A blend of PC and ABS that creates a stronger plastic.

Used in car interior and exterior parts, and mobile phone bodies.• Polyurethanes (PU) - Cushioning foams, thermal insulation foams, surface coatings, printing rollers (Currently

6th or 7th most commonly used plastic material, for instance the most commonly used plastic found in cars).

Special purpose plastics• Melamine formaldehyde (MF) - One of the aminoplasts, and used as a multi-colorable alternative to phenolics, for

instance in moldings (e.g., break-resistance alternatives to ceramic cups, plates and bowls for children) and thedecorated top surface layer of the paper laminates (e.g., Formica).

• Plastarch material - Biodegradable and heat resistant, thermoplastic composed of modified corn starch.• Phenolics (PF) or (phenol formaldehydes) - High modulus, relatively heat resistant, and excellent fire resistant

polymer. Used for insulating parts in electrical fixtures, paper laminated products (e.g., Formica), thermallyinsulation foams. It is a thermosetting plastic, with the familiar trade name Bakelite, that can be molded by heatand pressure when mixed with a filler-like wood flour or can be cast in its unfilled liquid form or cast as foam(e.g., Oasis). Problems include the probability of moldings naturally being dark colors (red, green, brown), and asthermoset it is difficult to recycle.

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• Polyetheretherketone (PEEK) - Strong, chemical- and heat-resistant thermoplastic, biocompatibility allows foruse in medical implant applications, aerospace moldings. One of the most expensive commercial polymers.

• Polyetherimide (PEI) (Ultem) - A high temperature, chemically stable polymer that does not crystallize.• Polylactic acid (PLA) - A biodegradable, thermoplastic found converted into a variety of aliphatic polyesters

derived from lactic acid which in turn can be made by fermentation of various agricultural products such as cornstarch, once made from dairy products.

• Polymethyl methacrylate (PMMA) - Contact lenses, glazing (best known in this form by its various trade namesaround the world; e.g., Perspex, Oroglas, Plexiglas), aglets, fluorescent light diffusers, rear light covers forvehicles. It forms the basis of artistic and commercial acrylic paints when suspended in water with the use ofother agents.

• Polytetrafluoroethylene (PTFE) - Heat-resistant, low-friction coatings, used in things like non-stick surfaces forfrying pans, plumber's tape and water slides. It is more commonly known as Teflon.

• Urea-formaldehyde (UF) - One of the aminoplasts and used as a multi-colorable alternative to phenolics. Used asa wood adhesive (for plywood, chipboard, hardboard) and electrical switch housings.

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ptext?doc=Perseus:text:1999. 04. 0057:entry=#83506)[2] Plastic, Online Etymology Dictionary (http:/ / www. etymonline. com/ index. php?search=plastic& searchmode=none)[3] Composition and Types of Plastic (http:/ / www. infoplease. com/ ce6/ sci/ A0860420. html) Inforplease website[4] life cycle of a plastic product (http:/ / www. americanchemistry. com/ s_plastics/ doc. asp?CID=1571& DID=5972)[5] Classification of Plastics (http:/ / dwb. unl. edu/ Teacher/ NSF/ C06/ C06Links/ qlink. queensu. ca/ ~6jrt/ chem210/ Page3. html)[6] Periodic Table of Polymers (http:/ / www. pcn. org/ Technical Notes - Periodic Table of Polymers. htm) Dr Robin Kent – Tangram

Technology Ltd.[7] Heeger, A. J.; Schrieffer, J. R.; Su, W. -P.; Su, W. (1988). "Solitons in conducting polymers". Reviews of Modern Physics 60: 781.

doi:10.1103/RevModPhys.60.781.[8] Burroughes, J. H.; Bradley, D. D. C.; Brown, A. R.; Marks, R. N.; MacKay, K.; Friend, R. H.; Burns, P. L.; Holmes, A. B. (1990).

"Light-emitting diodes based on conjugated polymers". Nature 347: 539. doi:10.1038/347539a0.[9] Sariciftci, N. S.; Smilowitz, L.; Heeger, A. J.; Wudl, F. (1992). "Photoinduced Electron Transfer from a Conducting Polymer to

Buckminsterfullerene". Science 258 (5087): 1474. doi:10.1126/science.258.5087.1474. PMID 17755110.[10] Sirringhaus, H. (2005). "Device Physics of Solution-Processed Organic Field-Effect Transistors". Advanced Materials 17: 2411.

doi:10.1002/adma.200501152.[11] Edward Chauncey Worden. Nitrocellulose industry. New York, Van Nostrand, 1911, ISBN 1153059282 (2010 reprint) p. 568. (Parkes,

English patent #2359 in 1855)[12] Stephen Fenichell, Plastic: The Making of a Synthetic Century, HarperBusiness, 1996, ISBN 0887307329 p. 17[13] First Plastic in the World (http:/ / www. hackney. gov. uk/ ep-first-plastic-in-the-world. htm)[14] Celluloid, Webster's Online Dictionary, accessed on January 2009 (http:/ / www. websters-online-dictionary. org/ ce/ celluloid. html)[15] Jezek, Geno. "What is Vinyl?" (http:/ / www. whatisvinyl. com/ ). . Retrieved January 2011.[16] "Polyvinyl chloride" (http:/ / www. plasticsusa. com/ pvc. html). Plasticsusa.com. . Retrieved January 2011.[17] "Technical Support Document: Toxicology of Hydrogen Chloride" (http:/ / oehha. ca. gov/ public_info/ pdf/

TSDHydrogenChlorideMethLabs0204. pdf) (PDF). California EPA, Office of Environmental Health Hazard Assessment. Revised. p. 8. .Retrieved January 2011.

[18] "How can I preserve my family photographs for my grandchildren?" (http:/ / www. loc. gov/ preserv/ presfaq. html#5). The Library ofCongress Preservation FAQs. LoC. . Retrieved January 2011.

[19] Kinnane, Adrian (2002). DuPont: From the banks of the Brandywine to miracles of science. Baltimore, Md.: Johns Hopkins UniversityPress. pp. 116–125. ISBN 0-8018-7059-3.

[20] McRandle, P.W. (March/April 2004). "Plastic Water Bottles" (http:/ / www. thegreenguide. com/ doc/ 101/ plastic). National Geographic. .Retrieved 2007-11-13.

[21] Perinatal Exposure to Low Doses of Bisphenol A Affects Body Weight, Patterns of Estrous Cyclicity, and Plasma LH Levels, accessedMarch 2009 (http:/ / www. ehponline. org/ members/ 2001/ 109p675-680rubin/ rubin-full. html)

[22] Alonso-Magdalena, Paloma; Morimoto, Sumiko; Ripoll, Cristina; Fuentes, Esther; Nadal, Angel (January 2006). "The Estrogenic Effect ofBisphenol A Disrupts Pancreatic β-Cell Function In Vivo and Induces Insulin Resistance" (http:/ / www. ehponline. org/ docs/ 2005/ 8451/abstract. html). Environmental Health Perspectives 114 (1): 106–112. doi:10.1289/ehp.8451. PMID 16393666. PMC 1332664. ..

[23] Andrew Zajac FDA issues BPA guidelines (http:/ / articles. latimes. com/ 2010/ jan/ 16/ nation/ la-na-fda-bpa16-2010jan16), Los AngelesTimes, January 16, 2010

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[24] Lisa Wade McCormick More Kids' Products Found Containing Unsafe Chemicals (http:/ / www. consumeraffairs. com/ news04/ 2009/ 10/pirg_lead_tests. html), ConsumerAffairs.com, October 30, 2009

[25] Alan Weisman, "The World Without Us," St. Martin's Press, NY, 2007.[26] "Dioxins" (http:/ / www. oeconline. org/ our-work/ kidshealth/ toxics/ air/ dioxins). Oregon Environmental Council. .[27] Biodegradation of plastic bottles made from Biopol in an aquatic ecosystem under in situ conditions, accessed March 2009 (login required)

(http:/ / www. springerlink. com/ content/ n651104158x43255/ )[28] CORDIS: Search CORDIS: Projects (http:/ / cordis. europa. eu/ search/ index. cfm?fuseaction=proj. document& CFTOKEN=19120617&

PJ_RCN=7901178& CFID=6808047)[29] Spain: Scientists Close To Making Biofuel From Algae (http:/ / www. tmcnet. com/ usubmit/

-spa-scientists-close-making-biofuel-from-algae-/ 2006/ 08/ 07/ 1777815. htm)[30] 'Sugar plastic' could reduce reliance on petroleum (http:/ / www. newscientist. com/ article/

dn9440-sugar-plastic-could-reduce-reliance-on-petroleum. html)[31] http:/ / www. dailymail. co. uk/ sciencetech/ article-1345789/ MakerBot-Thing-O-Matic-The-portable-factory-box-create-3D-object-plastic.

html

• Substantial parts of this text originated from An Introduction To Plastics v1.0 (http:/ / web. archive. org/ web/20070810225820/ http:/ www. vectorsite. net/ ttplast. html) / 1 March 2001 / greg goebel / public domain.

External links• J. Harry Dubois Collection on the History of Plastics, ca. 1900–1975 (http:/ / americanhistory. si. edu/ archives/

d8008. htm) Archives Center, National Museum of American History, Smithsonian Institution.• Material Properties of Plastics – Mechanical, Thermal & Electrical Properties (http:/ / www. plasticsintl. com/

sortable_materials. php?display=mechanical)• List of over 600 plastics (http:/ / www. ides. com/ plastics/ default. htm)• Plastics Historical Society (http:/ / www. plastiquarian. com/ )• History of plastics, Society of the Plastics Industry (http:/ / www. plasticsindustry. org/ AboutPlastics/ content.

cfm?ItemNumber=670& navItemNumber=1117)• What Are Plastics Made Of? (http:/ / www. popsci. com/ archive-viewer?id=cycDAAAAMBAJ& pg=58&

query=B-25) January 1943 Popular Sciencebjn:Panyu

Article Sources and Contributors 12

Article Sources and ContributorsPlastic  Source: http://en.wikipedia.org/w/index.php?oldid=408644041  Contributors: - ), -Bobby, 123kapil, 7, 8thstar, A Macedonian, A Train, ABF, AC+79 3888, Abductive, Abhijithpkumar,Abmac, Acroterion, Adashiel, AdjustShift, Adrian, Adrian Glamorgan, AgentSteel, Ahering@cogeco.ca, Ahoerstemeier, AirdishStraus, Aitias, Ajbabixx, Akshaya sriram, Alan Liefting,Alansohn, Albertoeba, Aldaron, Ale jrb, Alex Bakharev, Alex Rio Brazil, Alexius08, Allmightyduck, Alpha 4615, Alphax, Amal75, Amcbride, Amplitude101, An0nymouse, AnOddName,Anabus, Anastrophe, Anaxial, AndreasJS, Andres, AndrewHowse, Andrewpmk, Andros 1337, Andycjp, Anna Frodesiak, Anna Lincoln, Anon1245, Antandrus, Antman102, Apalgoel, Apothecia,Appeltree1, AquaGeo, Arakunem, Arjun01, Arrowofyourdeath, Arthurthefirst, Askari Mark, Atif.t2, Aua, Avitor, Avm1111, AxelBoldt, Ayax el cronopio, Az1568, Baberg, Bantosh, Bartledan,Baseball-bob, Bcartolo, Begoon, Beland, BenFrantzDale, Beregond5, Bert Hickman, Bgold4, Bhadani, Bhumiya, BiT, Biederman, BigBodBad, Bigtimepeace, Billlund, Bináris, Blanchardb,Blaxthos, Blotwell, Bluerasberry, Bmiller 73, Bob, Bobcutie, Bobet, Bobianite, Bobo192, Bogey97, Bomac, Bongwarrior, Boogster, BoomerAB, Boomshadow, Bootneylees, BraneJ, Brian0918,Bruce89, Bryan Derksen, Bryan986, Bubba hotep, Bubonic plague, Bunnyhop11, Burgercat, Cacycle, Callsign, Caltas, Camw, Can't sleep, clown will eat me, CanisRufus, CannotResolveSymbol,CapitalR, CardinalDan, Casito, Casper2k3, Cassavau, Catgut, CatherineMunro, Cdueck, Ceyockey, Cg2112, Chamal N, Charles Gaudette, CharlesC, Che829, Ched Davis, ChemGardener,ChemNerd, Chowbok, Chrislk02, Christian75, Christopher Parham, Christopherlin, Chriswiki, Chvhch, Claudiaprinstein, Clear perspective, Closedmouth, Cmgoogin, Coasterlover1994,Codingmasters, Coewiddabikdik, Coffee, Cohesion, Colfer2, ColinClark, Combatentropy, Confiteordeo, Conversion script, Cookiez33, CoolMike, Courcelles, Cpl Syx, Creidieki, Cremepuff222,Cuddlyable3, Curtsurly, CustardJack, Cutler, Cwoyte, Cyktsui, Cynthia Bennett, Czrinindia, D0762, DARTH SIDIOUS 2, DCEdwards1966, DJ.Sandros12, DSRH, DVD R W, Da monster underyour bed, DaL33T, DabMachine, Daniel Olsen, Daniel Quinlan, DanielCD, Danieltiger45, Darth Mike, DaveSumpner, David Gale, David spector, DavidCary, DavidLevinson, Dawn Bard,Dbfirs, Dc987, Dcfrely, Ddruk, Debresser, December21st2012Freak, Deeby, Dekisugi, Deli nk, Delldot, Denali134, Deor, DerHexer, Dffgd, Dicklyon, Dillard421, Dismas, DivineXiao, DocStrange, DocWatson42, DocendoDiscimus, Doddsie, Dog123, Dogcow, Dogears, Dogman15, DonSiano, Donbert, Doniago, Doseiai2, DoubleBlue, Dougz1, Dr. Kaplas, DrBob, Drbeach,Dreadstar, Dream Focus, Dsp13, Ducati38, Duk, Dycedarg, E Wing, ECWAnna, Eagleal, Edcolins, Edderso, Edgar181, Edison, Edstoves, Edward, Eequor, Egil, Elembis, Eliezerh, Elisaassay,Ellywa, Emcee, Emubob59, Entellegence, Enviroboy, Epbr123, Ephebi, Epitaf, Erik Carson, Evanscnce, Everyking, Excirial, Eyrian, Fabrictramp, Fact idiot, Falseinfo, Faradayplank,Fat&Happy, Favonian, Femto, Ferkelparade, Ferret face, Fetchcomms, Fetofs, Fieldday-sunday, Firedude231, Fl, Flewis, Flowerpower1256, Fngosa, Forton, Fram, Fran Rogers, Fredrik,Fritzpoll, Frogger3140, Fudoreaper, Fusionmix, Fyyer, GB fan, GD 6041, GDonato, GHe, GOER, GRAHAMUK, GTBacchus, Gail, Gaius Cornelius, Garfield226, GargoyleMT, Gary King,Garyzx, Geedubber, GeoGreg, Gerweck, Ggrreeggg, Ghazwan1234567890, Ghewgill, Giftlite, Ginsengbomb, Gjd001, Gobonobo, God Emperor, Gogo Dodo, GoneAwayNowAndRetired,Gorgeouschick, Grafen, Graham87, Green940, Greudin, Ground Zero, Gsarwa, Gurch, Gurchzilla, Gzkn, HJ Mitchell, Hadal, Haham hanuka, Hanacy, Hangman.m, HappyCamper, Hardyplants,Harmless rebellion, HarryHenryGebel, Harryboyles, Hazard-SJ, Hdt83, Hemant 17, HenryLi, Heron, Hevnakifly, Hidanielyourock, Hiphopdontstop, Hiteshg105, Hobartimus, HolIgor,Hotcrocodile, Htfiddler, Hugo-cs, Huntereyesman, Hut 8.5, Hydrogen Iodide, I am a lemon, II MusLiM HyBRiD II, ISC PB, IWUVwabbits, Iamamarine, Ibbn, Igrowsolutions, ImGz, Immunize,Imoen, ImperfectlyInformed, Imroy, Inkypaws, Instinct, Intelati, InverseSubstance, Iridescent, IrisKawling, Isopropyl, J Michalek, J. Spencer, J.delanoy, JForget, JNW, Jackehammond, JakeWartenberg, James086, JamesAM, JamesBWatson, Jamesontai, Jammy dodga, Jaranda, Jarekt, Jauhienij, JavierMC, Javierito92, JcCoPM, Jeff G., Jeffozvold, Jenny66, Jesterbard, Jhaegele,Jknez1, JoanneB, John, John of Reading, John254, JohnCD, JohnnyB256, Jojit fb, Jonnie5, Jooler, Jorend, Jorge Stolfi, Joshlepaknpsa, Joshua, Jovianeye, Joyous!, Jr1038, Jrtayloriv, JulesH,Julesd, Juliancolton, Jullianisawesome, Justfred, Justin W Smith, KFP, KVDP, Kaiserb, Kamenev, Kanags, KarlM, Karol Langner, Karthik6129, Katana0182, Katoa, Kazikameuk, Keeves, KeithEdkins, Ken Gallager, Kenyon, Kickus, Killurmama45, King of Hearts, Kingfish, Kingpin13, Kingtilley, Kingturtle, Kipala, Kjkolb, Knd333, Konstable, Korath, Kousaalyabakthavalam, Kraftlos,KrakatoaKatie, Krawi, Krazymikeyd, Krulle, Kubigula, Kungming2, Kuru, Kwiki, LGF1992UK, LMB, Lahiru k, Lambyte, Landon1980, Landroo, Lankiveil, Lantrix, Lazylaces, LeaveSleaves,LedgendGamer, LeeWilson, Leolaursen, Leon7, Lesath, Leuko, Lexicon, Lightning, Lindorm, Linnell, Lisa4edit, LoOkLeFt, Loadeddesign, Logical2u, Lomacar, LonelyBeacon, Loren.wilton,Lost tourist, Louis Calvete, Louiscam, Luckharry, Lucyfanclub, Lukenjoel, Lumos3, Luna Santin, MC MasterChef, MER-C, MIckStephenson, MPerel, Mac, Mac Davis, Majopius, Mandarax,Manishearth, Manop, Manticore, Manuel Trujillo Berges, MarcoTolo, Masterblooregard, Matador, Materialscientist, Mattabat, Mav, Max rspct, Mazca, Maziotis, McGeddon, Mendaliv, Merope,Metallicradiation428, Metiscus, Mettimeline, Michael2, MichaelHenley, Michaelsploosh, Midwesttoolguy, Migi29, Miguel, Mike Doughney, Mike dill, Mild Bill Hiccup, Minghong, Minimac'sClone, Mishuletz, MissMJ, Mix999, Mkweise, Mmeeyy, Mmmeg, Mmxx, Moe Epsilon, Momoskido, Monkeyluv98, Moreschi, Morning277, Mosquitopsu, Mr2001, MrFish, Mrpabaloogi,Mstefaniak, Museerouge, Mushroom, Myanw, Mygerardromance, N419BH, NCurse, NVPBIOCR, Nagy, Nakon, Nancy, Naru12333, Natbrazil, Nathan jameson, NawlinWiki, Neparis, Netalarm,Neuro, NewEnglandYankee, Nickybutt, Nightfly, NittyG, Nivix, Nk, Nlu, Noahwass, Noclevername, Noisy, Non-dropframe, Nono64, Nos 4 speed, Nposs, Nucleophilicrxn, Nut er, Nyttend,Obbyyoyo, Od Mishehu, Oenus, OlEnglish, Olivier, OllieFury, Olliescampton, Onopearls, Ooblagis, Oooooo990, Open2universe, Orphan Wiki, Oxymoron83, P2020C, P30Carl, Pakaraki,PantsofAwe, Paul-L, Pax:Vobiscum, Pcbene, Pdn, Peter T.S., Peter.C, PeterJohnson, PeterWiki09, Petersam, Petri Krohn, Phact, Phidauex, Philip Trueman, Phædrus, PiMaster3, Piano nontroppo, Pinethicket, Pingswept, Pinkadelica, Plusle, Pmergner, Poing137, Poitypoity, Possum, PowerSane, Powermate, Press-yes, Prince of Dharma, Prmacn, Professor Fiendish, PseudoSudo,Pseudomonas, Puiokjh, Qbmessiah, Quaeler, Queeber, Quintote, Quizman1967, RJFJR, RMHED, RUL3R, RYNORT, Radioactivebloke, Radon210, Rahuloof, RainbowOfLight, Rainypenguin,Raremetalmining, Raven in Orbit, Ravik, Rdsmith4, Rebroad, Reconsider the static, Recycledagplastic, RedHillian, Regancy42, Reinyday, Reneeholle, RetiredWikipedian789, RexNL, Rfc1394,Rholton, Rich Farmbrough, Rifleman 82, Rmhermen, RobHarding, Robin63, RocketJohnson, Rodri316, Rollopets, Ronhjones, Rooboy715, Rory096, RoyBoy, Rrburke, Rror, Rtyq2, RustyCashman, Ryou-kun16, Ryulong, SCEhardt, SHeumann, SMC, Saif tinku, Samjohnson99, Samst2, Sananthara3, Sara USA, SarekOfVulcan, Sasha l, Sazzmee, ScAvenger, Scetoaux,SchfiftyThree, Schzmo, Scientizzle, Scimitar, Sciurinæ, Scjessey, Scyrene, Securiger, Senator Palpatine, Sesu Prime, Shadowjams, Shanes, Shawn in Montreal, Shenme, Sheps999, Shipmaster,Siawase, Sidd09, Sidhekin, Silverchemist, Siphonusa, Sjakkalle, Sjblock, Sjcole, Sjö, Skafantaris, SkarmoutsosV, Skunkboy74, SkyWalker, Slakr, Slaught420, Smeira, Snowolf, Sodium,Solace098, Solipsist, Solitude, Sonett72, Sonjaaa, Sophus Bie, SpLoT, Spellcast, SpellingGuru, Splash, Sponge, SpyMagician, Srose, Staffwaterboy, Starcraft101, Starxrandom, Steel, Stephen enelson, StephenBuxton, Stephenb, Steven Zhang, Stewartadcock, Stickee, Stokerm, Stuartfost, Stuston, Stw, Suffusion of Yellow, Superowls, Svetovid, Swift as an Eagle, Symane, Synchronism,T-borg, Tardigrada2008, Tarosan, Tasc, Tazzlon, Tbhotch, Teemu Ruskeepää, Templarion, Teo64x, Terence, TerraFrost, Tetracube, That Guy, From That Show!, The Kid, The Rambling Man,The Thing That Should Not Be, The Transhumanist, The spesh man, TheCarterVI, TheEgyptian, TheRanger, Theda, Theoneintraining, Theplastic, Thingg, Thunderboltz, Tide rolls, Timneu22,Timwi, Tintenfischlein, Toddst1, Tohd8BohaithuGh1, Tom, Tom harrison, TomPhil, Tommy2010, TonyBallioni, Trakov, TransporterMan, Triwbe, Trusilver, Tsman, Tsoares468, TutterMouse,Tvbrichmond, Twang, Twilo, Twinkle Bum, TylerJarHead, Tyrenius, UKSF, Ukexpat, Ulric1313, Unschool, Urfaceisfunny, Urhixidur, Usernamefortonyd, VMS Mosaic, Vague Rant, Valfontis,Van helsing, Versus22, VikOlliver, Vipinhari, Vogelfrei, Vortexrealm, Vrenator, Vsmith, Vssun, WHZhang, 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Image Sources, Licenses and ContributorsFile:Plastic household items.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Plastic_household_items.jpg  License: Creative Commons Attribution-Sharealike 3.0  Contributors:User:ImGzFile:Plastic food.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Plastic_food.jpg  License: Creative Commons Attribution 2.5  Contributors: Bantosh, N.MoriFile:Plastic pipe firestops nortown casitas.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Plastic_pipe_firestops_nortown_casitas.jpg  License: Public Domain  Contributors:User:Achim HeringFile:styrene polymerization.png  Source: http://en.wikipedia.org/w/index.php?title=File:Styrene_polymerization.png  License: Public Domain  Contributors: User:Edgar181File:vinylchloride polymerization.png  Source: http://en.wikipedia.org/w/index.php?title=File:Vinylchloride_polymerization.png  License: Public Domain  Contributors: User:Edgar181File:Condensation polymerization diacid diamine.svg  Source: http://en.wikipedia.org/w/index.php?title=File:Condensation_polymerization_diacid_diamine.svg  License: Public Domain Contributors: Calvero.File:Resin-identification-code-1-PETE.svg  Source: http://en.wikipedia.org/w/index.php?title=File:Resin-identification-code-1-PETE.svg  License: unknown  Contributors: Fvasconcellos,Remember the dot, TotoBaggins, 3 anonymous editsFile:U+2674 DejaVu Sans.svg  Source: http://en.wikipedia.org/w/index.php?title=File:U+2674_DejaVu_Sans.svg  License: Public Domain  Contributors: VariousFile:Resin-identification-code-3-V.svg  Source: http://en.wikipedia.org/w/index.php?title=File:Resin-identification-code-3-V.svg  License: unknown  Contributors: Remember the dot,TotoBagginsFile:Resin-identification-code-4-LDPE.svg  Source: http://en.wikipedia.org/w/index.php?title=File:Resin-identification-code-4-LDPE.svg  License: Public Domain  Contributors: Originaluploader was TotoBaggins at en.wikipediaFile:Resin-identification-code-5-PP.svg  Source: http://en.wikipedia.org/w/index.php?title=File:Resin-identification-code-5-PP.svg  License: unknown  Contributors: Remember the dot,TotoBagginsFile:Resin-identification-code-6-PS.svg  Source: http://en.wikipedia.org/w/index.php?title=File:Resin-identification-code-6-PS.svg  License: unknown  Contributors: Remember the dot,TotoBaggins

Image Sources, Licenses and Contributors 13

File:Resin-identification-code-7-OTHER.svg  Source: http://en.wikipedia.org/w/index.php?title=File:Resin-identification-code-7-OTHER.svg  License: unknown  Contributors: Erwin,Remember the dot, TotoBaggins, 1 anonymous editsFile:Cadeira Palmetal - Modelo I - Preta - Simples.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Cadeira_Palmetal_-_Modelo_I_-_Preta_-_Simples.jpg  License: Free Art License Contributors: Palmetal Metalúrgica - Palmetal

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