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PLASTICS - Coggle Diagram
PLASTICS
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Shaping and finishing techniques Pnnmpal techniques are cutting, perforating, trimming and filing.
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TRIMMING AND FILING
• A file has a rough surface. • Used to fimsh the surfaces and edges of hard matenals.• A rasp has an even rougher surface, covered with teeth' • Used to finis the surfaces and edges of soft materials
Joining plastics When plastics have been formed, shaped and finished, we can loin
pieces to each other.
The points can be permanent or temporary
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Permanent joints. We use this type of joint when we don't want to separate or dismantle
the pieces.
We can use adhesives or soldenng
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Textiles and leather.We use textiles in the form of threads to produce cloth. They can be natural or synthetic.
Natural fibres and leather. Leather is made from animal skins chemically treated to keep its quality
and beauty
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. Synthetic fibres
Synthetic fibres such as nylon, polyester, rayon and Lycra' are plastics.
They are long-lasting, resistant and waterproof.
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PROPERTIES OF PLASTICS
The propertres of plastrcs depend on their type and on their crushed: reduced to very small pieces by mechamcal pressure Colllposltloll. Strength, elasticity, rigidity and flexibtflty
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other properties: low density, impermeability
mechanical: malleabrlity, ductility, mechanical resrstance
ECOLOGICAL PROPERTIES
We can recycle plastics. There are three recycling processes; chemical,
mechantcal and energetrc
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CHEMICAL RECYCLING. We apply chemical processes to make new
materials from the original components of plastic residues.
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FORMARTION TECHNIQUES
When we manufacture plasttc obiects ln Industry, the plastic Is avadable In three different forms, powder, granules and resins.We use different formation techniques depending on the type and use of
the plastic.
Lamination
Thermoplastic produced by the extrusion method ls passed through a
senes of hot cylinders to produce sheets of varying thtckness.
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Vacuum forming
We use plastic sheets with a large surface for this technique. 
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We extract the air below the sheet so that the plastic ts pulled against
the instde walls of the shaped mould, and the desired form ts created
We leave the mould to cool, then remove the obiect
Extrusion
This technique has four stages
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Finally, we collect the pieces of plastic through a feeder system.
We apply pressure by means of a large, rotattng screw, whtch forces
the melted matenal out, through a nuzzle.
We put thermoplastic, in granular form, Into a previously heated cyhnder
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