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[[File:Thermoforming animation.gif|400px|right|Thermoforming animation]]
Since the development of early [https://en.wikipedia.org/wiki/Plastic '''Plastics'''], such as [https://en.wikipedia.org/wiki/Celluloid '''Celluloid'''], [https://en.wikipedia.org/wiki/Bakelite '''Bakelite'''], [https://en.wikipedia.org/wiki/Poly(methyl_methacrylate) '''Perspex'''] and [https://en.wikipedia.org/wiki/Nylon '''Nylon'''], an ever-expanding variety now surrounds us, not only mimicking traditional or natural materials but also bringing with them particular properties and characteristics. The word ‘plastic’ is derived from ‘plastikos’, a  Greek word meaning ‘capable of being shaped or molded’.
Since the development of early [https://en.wikipedia.org/wiki/Plastic '''Plastics'''], such as [https://en.wikipedia.org/wiki/Celluloid '''Celluloid'''], [https://en.wikipedia.org/wiki/Bakelite '''Bakelite'''], [https://en.wikipedia.org/wiki/Poly(methyl_methacrylate) '''Perspex'''] and [https://en.wikipedia.org/wiki/Nylon '''Nylon'''], an ever-expanding variety now surrounds us, not only mimicking traditional or natural materials but also bringing with them particular properties and characteristics. The word ‘plastic’ is derived from ‘plastikos’, a  Greek word meaning ‘capable of being shaped or molded’.


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<span style="color: green">'''Note:''' this phrase also defines '''[[Malleability]]''' and many materials have a '''[[Young's Modulus|Plastic Stage]]''' as they are deformed. To avoid confusion, '''DT Online''' uses the term '''Plastics''' as both a singular and plural noun)</span>)''
<span style="color: green">'''Note:''' this phrase also defines '''[[Malleability]]''' and many materials have a '''[[Young's Modulus|Plastic Stage]]''' as they are deformed. To avoid confusion, '''DT Online''' uses the term '''Plastics''' as both a singular and plural noun)</span>)''
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Synthetic* [https://en.wikipedia.org/wiki/Plastic '''Plastics'''] are chemically produced from oil and a wide, possibly infinite, variety is possible, but they all fit into one of two groupings:


* [https://en.wikipedia.org/wiki/Thermoplastic '''Thermoplastics'''] - these can repeatedly be softened by heating and will return to a rigid state when cooled.
The almost universal use of plastics for packaging and other throw-away items is causing considerable environmental issues since they do not rot very easily. Also, most plastics are made from oil which is a diminishing resource so there is increasing demand for them to be recyclable. Much work currently therefore, is focussed on the research and development of [https://en.wikipedia.org/wiki/Biodegradable_plastic '''Biodegradable Plastics'''] which are derived from renewable resources.
** this group includes: [https://en.wikipedia.org/wiki/Poly(methyl_methacrylate) '''Acrylic'''], [https://en.wikipedia.org/wiki/Polycarbonate '''Polycarbonate ''(PC)'''''], [https://en.wikipedia.org/wiki/Polyethylene '''Polyethylene'''], and [https://en.wikipedia.org/wiki/Polypropylene '''Polypropylene'''].
* [https://en.wikipedia.org/wiki/Thermosetting_polymer '''Thermosets'''] - these are initially ‘cured’ ''(or set)'', often by mixing with a ‘hardener’ which creates a heat producing ''([https://en.wikipedia.org/wiki/Exothermic_process '''Exothermic'''])'' chemical reaction and, once set cannot be softened again by further heating.
** this group includes: [https://en.wikipedia.org/wiki/Polyester '''Polyester Resin'''], [https://en.wikipedia.org/wiki/Epoxy '''Epoxy Resin'''], [https://en.wikipedia.org/wiki/Bakelite '''Bakelite'''] and [https://en.wikipedia.org/wiki/Melamine '''Melamine'''].
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<span style="color: green">'''*Note:'''
Several natural materials may also be classified as '''''Plastics'''''. These include: [https://en.wikipedia.org/wiki/Cellulose '''Cellulose'''], [https://en.wikipedia.org/wiki/Keratin '''Horn'''], [https://en.wikipedia.org/wiki/Amber '''Amber'''], and [https://en.wikipedia.org/wiki/Shellac '''Shellac'''].
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[[File:Polyethylene-terephthalate-3D-balls.png|400px|right|Polyethylene-terephthalate-3D-balls]]
[https://en.wikipedia.org/wiki/Plastic '''Plastics'''] are formed by long chains of carbon based molecules, or [https://en.wikipedia.org/wiki/Polymer '''Polymers'''], strongly bonded to each other.  The [https://en.wikipedia.org/wiki/Polymer#Chain_length '''Polymer Chains'''] are either joined to each other with weak [https://en.wikipedia.org/wiki/Van_der_Waals_force '''van der Vaals Forces'''] to create [https://en.wikipedia.org/wiki/Thermoplastic '''Thermoplastics'''] or much stronger [https://en.wikipedia.org/wiki/Cross-link '''Cross-Linking'''] which results in [https://en.wikipedia.org/wiki/Thermosetting_polymer '''Thermosets'''].




The almost universal use of plastics for packaging and other throw-away items is causing considerable environmental issues since they do not rot very easily. Also, most plastics are made from oil which is a diminishing resource so there is increasing demand for them to be recyclable. Much work currently therefore, is focussed on the research and development of [https://en.wikipedia.org/wiki/Biodegradable_plastic '''Biodegradable Plastics'''] which are derived from renewable resources.
[[Category:Skills and Processes]]

Latest revision as of 19:50, 16 November 2016

Thermoforming animation

Since the development of early Plastics, such as Celluloid, Bakelite, Perspex and Nylon, an ever-expanding variety now surrounds us, not only mimicking traditional or natural materials but also bringing with them particular properties and characteristics. The word ‘plastic’ is derived from ‘plastikos’, a Greek word meaning ‘capable of being shaped or molded’.

Note: this phrase also defines Malleability and many materials have a Plastic Stage as they are deformed. To avoid confusion, DT Online uses the term Plastics as both a singular and plural noun))

The almost universal use of plastics for packaging and other throw-away items is causing considerable environmental issues since they do not rot very easily. Also, most plastics are made from oil which is a diminishing resource so there is increasing demand for them to be recyclable. Much work currently therefore, is focussed on the research and development of Biodegradable Plastics which are derived from renewable resources.

Pages in category 'Working Plastics'

The following 5 pages are in this category, out of 5 total.

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Media in category 'Working Plastics'

The following 16 files are in this category, out of 16 total.

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