1. So, what’s the link?
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Paperclips are like monomers – many single units.
A paperclip chains are like polymers – many monomers joined together in a long chain.
“Mono” means “Single”, “Mer” means “Part”: Monomer = Single Part
“Poly” means “Many”: Polymer = Many Parts.

2. Polymer name: Poly(Clip)
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Naming Polymers
Monomer name: Clip
Polymer name: Poly(Clip)
Naming paperclips is quite easy!
Take the name of the monomer and put it in brackets.
Put the word “Poly” before this”.
Try naming the polymers for:
Butene
Vinyl choride
Styrene
Poly(butene)
Poly(vinyl chloride)
Poly(styrene)

3. Drawing monomers and polymers
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Separately, ethene and propene would be “monomers”.
The carbon-carbon double bond can break, allowing the molecules to join!

4. Polymerisation
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The joining together of many monomer molecules to make long chained polymers is called polymerisation.
You will only need to deal with “Addition Polymerisation” at GCSE.
This requires the use of UNSATURATED MONOMER MOLECULES: a carbon-carbon double bond is required.
Without this, other monomer units cannot join on.

5. Polymerisation
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What do I need to do to the propene and poly(propene) to make it correct?

6. Do now: Copy + complete the review grid about monomers/polymers

7. Crosslinking or just intermolecular forces?
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Crosslinking or just intermolecular forces?
Let’s add some crosslinking to our polymer chains:
Weak intermolecular forces between.
Allows the polymer to soften/melt.
Can be recycled/remoulded.
Strong covalent cross-links.
Are rigid, not flexible.
Do not melt.

8. Key Example: LDPE vs. HDPE
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Use the table below to write a “long-answer” style response that compares the methods of producing LDPE and HDPE and explains why they’re needed. Key terms: monomer, polymer, conditions.

9. Key Example: LDPE vs. HDPE
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Example points:
LDPE and HDPE made using the same monomer (ethene).
The reaction conditions for making LDPE are different to HDPE.
For LDPE a higher pressure of 2000atm is used, compared to 2atm for HDPE.
For LDPE a higher temperature of 200°C is used, as opposed to 60°C for HDPE.
There is a Ziegler-Natta catalyst used to make HDPE which helps to form less branched chains than in LDPE.
The less branched HDPE polymer units can pack tighter together than the LDPE polymer units, which are more branched.
Greater branching increases flexibility, less branching increases rigidity.

10. Ziegler-Natta catalyst
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The closer the polymer chains can pack, the stronger they interact.
Ziegler-Natta catalysts reduce branching (right hand picture).
Allows polymer chains to pack closely.
Harder, more durable material.

11. Key Example: LDPE vs. HDPE
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Workbook Questions:
Complete the workbook questions about polymers: Pages…