E.g. The polymerisation of Ethane C2H4 :
Good for plastic bags & buckets etc
E.g. The polymerisation of Propene C3H6 :
Good for ropes etc
E.g. The polymerisation of Styrene :
Packaging, foam cups etc.
E.g. The polymerisation of Vinyl Chloride :
Window frames, waterproof clothing etc
E.g. The polymerisation of Tetrafluroethene :
(Non-stick coating - Teflon)
The co-valent bonds holding the long molecules together are very strong. Few bacteria can make them rot down. They tend not to be Biodegradable.(What does this word mean?)
This makes disposing of plastics difficult:
Burning them produces oxides of Carbon, Hydrogen and sometimes Sulphur and other toxic compounds:
Carbon Dioxide, Sulphur Dioxide, Water vapour
They fill up land-fill sites.
(Why should these factors be a problem?)
Recycling plastics is complicated by several issues:
·Not all plastics lend themselves to recycling
·Different types of plastic have different properties, and so separation is very important.
·The economics of recycling are not always favourable, as the market is prone to fluctuate. For example, when oil prices fall the production of ‘new’ plastics become cheaper, so providing its recycled counterpart with greater competition.
·Unlike some countries a lack of subsidy in the UK makes a recycling industry more difficult to sustain, so nationally our recycling performance tends to lag behind many of our European neighbours.
However, increasing pressures on landfill sites, and our need to conserve natural resources makes recycling of plastics an important step forwards.