C2: Material Choices

C2: Material Choices

1. Natural and synthetic materials

   • Natural
     • Wood
     • Paper
     • Cotton
     • Wool
     • Silk
   • Synthetic
     • Rubber
     • Nylon
     • Polyester
     • You can control its properties

2. Materials, properties and uses

   • Plastic
     • Fairly hard, strong and stiff
     • Low density
     • Some are mouldable
   • Rubber
     • Strong but soft
     • Mouldable
   • Nylon Fibres
     • Soft and flexible
     • Good tensile strenght

3. Crude oil

   • Is a mixture of hydrocarbons
   • Proporties change as the chain gets older
   • Shorter chains the lower the boiling point
   • Long chains have high boiling points
   • When heated shorter chains boil leaving the longer ones behind
   • Most used as fuels
   • Some use as plastics, medicines, feritlisers and even food

4. Polymerisation

   • Lots of small molecules linked together
   • Usually carbon based
   • There are lots of different types of polymers
   • Polyethene is strong and rigid an is used to make plastic bottles
   • PVC is strong and durable and it can be made to be either rigid or strechy

5. Nanotechnology

   • Nanoparticles are 1-100 nanometers
   • Nanoparticles have a larger surface area to volume ratio
   • This give them different proporties and makes them super useful
   • Silver nanoparticles can kill bacteria making them them suitable for would dressings
   • New products need to be tested thouroughly
   • The long term effects arent really understood
   • Products containing nanoparticles should be clearly labelled