Title: POLYMERS
1POLYMERS
R W Grime Ripon Grammar School
2POLYMERS
Addition polymers
Condensation polymers
3(No Transcript)
4Some definitions
Polymer
long chain molecule made from lots of small
molecules joined together
Monomer
small molecules that join together in
polymerisation
Addition Polymerisation
formation of long chain molecules from lots of
small molecules joining together with no other
product
Condensation Polymerisation
formation of long chain molecules from lots of
small molecules joining together with a small
molecule (e.g. water) released
5Addition polymers
http//users.argonet.co.uk/users/hoptonj/polymer.h
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6Addition polymers
n
ethene
poly(ethene)
polythene
7Addition polymers
n
phenylethene
poly(phenylethene)
polystyrene
8Addition polymers
n
methyl 2-propenoate
poly(methyl 2-propenoate )
perspex
9Addition polymers
n
methyl 2-cyanopropenoate
poly(methyl 2-cyanopropenoate)
superglue
10Addition polymers
n
chloroethene
poly(chloroethene)
PVC
11Addition polymers
n
tetrafluoroethene
poly(tetrafluoroethene)
PTFE / Teflon
12Addition polymers
n
propene
poly(propene)
13Addition polymers
- Catalysts are used for the polymerisation, and
the exact mechanism depends on the catalyst and
alkene (it is not electrophilic addition it is
usually catalytic addition).
- Polyalkenes are inert, although can burn.
- As they are inert, they are non-biodegradable.
14Condensation polymers
- Condensation polymers are polymers formed from
condensation reactions between monomers. A small
molecule (often water) is produced as well as the
polymer.
- Many natural polymers are condensation polymers,
e.g. silk, starch and DNA.
- The two main types are polyesters and polyamides.
15Polyesters
- Esters are formed on reaction between carboxylic
acids and alcohols.
- Polyesters are formed when dicarboxylic acids
react with diols.
- Polyesters are hydrolysed (in the presence of
strong acid or a specific enzyme) into their
constituent acid and alcohol, so they are
bio-degradable .
16Polyesters
strong acid or specific enzyme - H2O
17Polyesters
strong acid or specific enzyme
18Polyesters
Kevlar
19Polyesters
- Amides are formed on reaction between carboxylic
acids and amines.
- Polyamides are formed when dicarboxylic acids
react with diamines.
- Polyamides are hydrolysed (in the presence of
strong acid or a specific enzyme), so they are
bio-degradable.
. .
20Polyamides
strong acid or specific enzyme
21Polyamides
strong acid or specific enzyme