Polymers

Polymers

1. Types of Polymers and their Uses

   • Poly(phenylethene) or Polystyrene
     • Poly(
     • Used in: Foam packaging, insulation and model making
     • Biodegradable materials are now replacing polystyrene packing as environmental pressure grows to use less of this type of packaging.
   • Poly (propene) or Polypropylene
     • Used in: Food packaging, as a fibre in carpets and in synthetic ropes.
     • Also used as a material for certain lab equipment, due to its resistance to chemical attack.
   • Poly (ethene) or polythene
     • The most widely- used plastic, used to make shopping bags, shampoo bottles and toys.

2. Polymer Waste

   • Most polymers are non- biogradable
     • Fill up landfill sites. It is feared that landfill space in the UK will run out within a decade.
     • 85% of plastics end up in landfill, 8% are incinerated and 7% are recycled.
     • The non- biodegradability of plastics is a major reason why plastics need to be recycled.

3. Recycling Polymers

   • The best way to protect the environment is to first re-use and then recycle polymers.
     • For every tonne of plastic recycled, it is estimated that 1.8 tonnes of oil are saved.
     • PET and high density poly(ethene) plastic bottles are the most common polymers to be recycled.
   • Sorting
     • Before plastic waste can be processed, it has to be sorted into groups depending on the particular polymer.
   • Reclamation
     • Once sorted, the polymer are processed.
     • The polymers are chopped into small flakes, washed and then melted down and remoulded.

4. Polymers as a Fuel Source

   • Burning polymers
     • Under controlled conditions, burning polymers produces heat energy, which can be harnessed to make electricity.

5. Biodegradable and Compostable Polymers

   • Bioplastics will degrade naturally
     • A biodegradable plastic will break down as a result of bacterial activity.
     • They are derived from raw materials such as starch, maize, cellulose and lactic acid.
     • Most plastic bags are now biodegradable.

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