Unit 4 - Lesson 14: Addition Polymers Flashcards
What are polymers?
Large molecules made of repeating subunits.
Describe the molecular masses of polymers.
Polymers have large average relative molecular masses (on average they are very large molecules).
Polymers are large molecules made of repeating subunits. What are these subunits called?
Monomers.
What is joining monomers to make a polymer called?
Polymerisation.
What does poly mean?
‘Many’
What does polymer mean?
‘Many monomers’
What is polymerisation?
Joining monomers to make a polymer.
What are the two types of polymer?
- Addition polymers
- Condensation polymers
What is the homologous series of addition polymers? Does this make them saturated or unsaturated?
Addition polymers are always alkenes, therefore they are unsaturated.
What is the process of bonding alkenes to make an addition polymer called?
Addition polymerisation.
What is addition polymerisation?
The process of bonding alkenes to make an addition polymer. Addition polymerisation means monomers are added together with no extra molecules made.
What three things are needed for addition polymerisation to occur?
High temperatures, pressures, and an initiator.
What is an initiator?
An initiator is like a catalyst but is used up in the reaction.
The ends of polymer chains remain ‘unfinished’. What are the unfinished lines?
Continuation bonds.
https://i.pinimg.com/736x/a2/a5/d2/a2a5d25bfbbb1eb0887b742758056c63.jpg
Draw the addition polymerisation of ethene. Include labels.
a) What does the ‘n’ in this diagram represent?
b) What is the polymer called?
c) Is ethene an alkene or alkane? Saturated or unsaturated?
d) Is poly(ethene) an alkene or alkane? Does it turn bromine water colourless or not?
https://i.pinimg.com/736x/d9/59/4c/d9594c6cb4338d7ebc7d9967bfa493e7.jpg
a) The ‘n’ represents the number of subunits.
b) The polymer in this example is called poly(ethene).
c) Ethene is an alkene. It’s unsaturated.
d) Poly(ethene) is an alkane. It doesn’t turn bromine water colourless.
What does the polymerisation of propene make?
Poly(propene), which used to be called polypropylene.
Draw the addition polymerisation of propene.
a) Why have you drawn propene with CH3?
b) Why are the ends of the polymer chains ‘unfinished’?
https://i.pinimg.com/736x/b9/99/4f/b9994f4db4b062f4cacf45d12dcc72bb.jpg
a) This makes it easier to draw in long chains.
b) Those unfinished lines are continuation bonds. You must include them. Parts of the initiator are here.
Draw the addition polymerisation of chloroethene (ethene with 1 hydrogen replaced by Chlorine).
a) What is the polymer called?
https://i.pinimg.com/736x/d0/ca/ef/d0caefe51a14888feb3cb3054749a66b.jpg
a) Poly(chloroethene), once called polyvinylchloride (PVC).
Draw the addition polymerisation of tetrafluoroethene (all 4 hydrogen are replaced with fluorine)
https://i.pinimg.com/736x/42/7d/eb/427deb5d152fcc7ac2eace0e206448c8.jpg
What are the two types of poly(ethene)?
High-density (HDPE) and low-density (LDPE).
What is LDPE used for?
It’s used to make plastic carrier bags.
Is LDPE flexible and weak or strong and rigid?
LDPE is flexible and not too strong.
What is HDPE used for?
HDPE is used for plastic bottles and milk bottle lids.
Is HDPE flexible and weak or strong and rigid?
HDPE is strong and rigid.