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Addition polymerisation is when small molecules called monomers join together to form a larger molecule. Poly(ethene) is made by addition polymerisation as it is the joining of hundreds of ethene molecules together. ...
R步 + H2C == CH2 ↙ R 〞CH2 〞 CH2步
Stage 2- Propagation- the radical reacts with an ethene molecule
R〞CH2〞CH2步 + H2C==CH2 ↙ R〞CH2〞CH2〞CH2〞CH2步
The new molecule is also a radical, so more ethene molecules can be added.
R〞CH2〞CH2〞CH2〞CH2步 + H2C == CH2 ↙ R〞CH2〞CH2〞CH2〞CH2〞CH2〞CH2步
Ethene molecules continue to be added until
Stage 3- Termination- Two radicals join together
R〞(CH2) n〞CH2步 + R步 ↙ R〞(CH2) n〞CH2〞R
If the end of the chain containing the radical is close to an earlier parts of the drain the end carbon atom further up the chain. ... A highly branched poly(ethene) molecule has a low density.
Poly(ethene) has two different forms, LDPE, low density poly(ethene) and HDPE, high density poly(ethene). ...
There are three different forms of poly(propene). ... As the chains are unable to be packed closely there will be few intermolecular forces and they will be weak which means atactic poly(propene) has a low tensile strength. ...
Poly(ethene) was discovered by accident by Gibson and Fawcett in 1933.
Approximate Word count = 1090
Approximate Pages = 4.4
(250 words per page double spaced)
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