Plastic and rubber, was ist das?
Plastic and rubber are amorphous (disordered, noncrystalline) materials whose basic microscopic units are polymers: long chains of identical molecules, stringed together like a necklace. Such a chain is shown below in Fig. 1 for polystyrene, which is made from little styrene molecule units. These units are known as the polymer's monomers (mono=1, poly=many). Also shown below is an expanded polysterene cup for soy sauce from a japanese takeaway, which is what about 10 to the power of 24, or Avogadro's number or a million million million million of these polystyrene chains look like from our macroscopic point of view.
Fig. 1. Polystyrene is a polymeric material which at molecularly consists of chains of styrene units. It can be moulded and expanded to make a light cup
Why plastic and rubber?
Because microscopically they consist of these little moecular chains, plastic and rubber have unique properties compared to other materials like wood, metal or glass. For example, the shock absorbing properties and gripping properties of rubber tyres, whether full of air or solid, are a blessing to anyone who cycles. Imagine cycling on a bumpy road with wheels like in Leonardo's famous prototype! (see a reconstruction below). The schock absorbing and gripping properties of rubber derive from the fact the polymers are like lots of small springs, entangled together like a spagetti in a bowl of pasta.
So plastics are light, but strong, they can be easily coloured or made opaque or transparent. Rubbers are elastic and grippy. Both of them are cheap to manufacture (at least at the moment, see below). But what is the ecological impact of man made plastics? Are they all "toxics", like in the Story of Stuff presentation . Answers in the next post! In the mean time, enjoy the Story of Stuff (probably better to watch in the website, but I also embed youtube version below).
Plastic and rubber are amorphous (disordered, noncrystalline) materials whose basic microscopic units are polymers: long chains of identical molecules, stringed together like a necklace. Such a chain is shown below in Fig. 1 for polystyrene, which is made from little styrene molecule units. These units are known as the polymer's monomers (mono=1, poly=many). Also shown below is an expanded polysterene cup for soy sauce from a japanese takeaway, which is what about 10 to the power of 24, or Avogadro's number or a million million million million of these polystyrene chains look like from our macroscopic point of view.
Fig. 1. Polystyrene is a polymeric material which at molecularly consists of chains of styrene units. It can be moulded and expanded to make a light cupBecause microscopically they consist of these little moecular chains, plastic and rubber have unique properties compared to other materials like wood, metal or glass. For example, the shock absorbing properties and gripping properties of rubber tyres, whether full of air or solid, are a blessing to anyone who cycles. Imagine cycling on a bumpy road with wheels like in Leonardo's famous prototype! (see a reconstruction below). The schock absorbing and gripping properties of rubber derive from the fact the polymers are like lots of small springs, entangled together like a spagetti in a bowl of pasta.
So plastics are light, but strong, they can be easily coloured or made opaque or transparent. Rubbers are elastic and grippy. Both of them are cheap to manufacture (at least at the moment, see below). But what is the ecological impact of man made plastics? Are they all "toxics", like in the Story of Stuff presentation . Answers in the next post! In the mean time, enjoy the Story of Stuff (probably better to watch in the website, but I also embed youtube version below).
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