Addition Polymers

• Polymers are long chain molecules formed when lots of small molecules, called monomers, join together
• The main carbon chain of polyalkenes is also usually non-polar. These factors result in addition polymers being very unreactive- polyalkenes are chemically inert.
• The monomers within a polymer chain have strong covalent bonds. The IMF between polymer chains are much weaker. Longer chains with fewer branched have stronger IMF.
• Poly(chloroethene):

  The covalent bonds between the chlorine and the carbon atoms are polar, with chlorine being more electronegative.

  There are permanent dipole-dipole forces between the polymer chains.

  This makes PVC a hard but brittle material

  Used to make drain pipes and window frames.
• Plasticisers:

  Adding a plasticiser makes a polymer bendier. The plasticiser molecules get between the polymer chains and push them apart. This reduces the strength of the IMF between the chains- so the chains can slide around more, making them more flexible.

  Plasticised PVC is used to make electrical cable insulation, flooring tiles and clothing.