Plastics

• Polymer

  substance or fibre with a molecular structure made up of smaller units bonded together.
• Natural polymer

  polymer made from natural sources
• What are the forms polymers can available in?


  film, bar, rod, granules, sheets
• Thermoforming polymers


  polymers can be softened by heating and moulded into almost any shape

  can used in bending, vacuum forming, moulding and extrusions

  can be recycled
• Thermosetting polymers


  cannot be reheated or reformed once they have been formed and cooled

  cannot be recycled

  excellent insulators
• Name all thermoforming plastics

  -Polypropylene (PP)

  -Polythene (PE)

  -polystyrene (PS)

  -Polyvinyl chloride (PVC)
• name all the thermosetting plastics

  melamine formaldehyde

  polyester resin

  epoxy resin
• polythene


  thermoforming

  tough, flexible, easily moulded

  used for carrier bags, bin liners, washing up bottles
• Polystyrene (PS)

  thermoforming

  lightweight, food safe, good impact strength

  used for disposable plastic cutlery, CD case , smoke detector, plastic models
• Polypropylene (PP)


  thermoforming plastic

  good chemical, heat resistance and semi-rigid

  used bucket, bowls, crates , toys and bottle caps
• Polyvinyl Chloride (PVC)


  thermoforming plastic

  resistant to corrosion, flexible, durable

  used for water pipes , window frames, raincoats
• Melamine Formaldehyde (MF)

  Thermosetting plastic

  tasteless, odourless, chemical, heat, shrink, hard, scratch and impact resistant