3 Alkenes - Polymers

Question 1

What are plastic polymers monomers?

Answer 1

Alkanes

Question 2

What are used to modify polymers?

Answer 2

Plasticisers, small molecules getting in between carbon chains, reduced IMF stregnth and allows chains to slide over eachother meaning the polymer becomes softer.

Question 3

Why can polymers not biodegrade?

Answer 3

Strong non-polar C-H and C-C bonds, means they are fairly unreactive.

Question 4

Pros and Cons of polymers?

Answer 4

Pros
- cheap to make
- mostly easily shaped
- makes a range of useful products
Cons
- Not easy to dispose of: non-biodegradeable, fill up landfill, burning polymers releases harmful gases, many polymers to recycle, huge impacts on the environment

Question 5

4 Key polymers

Answer 5

LDPE
HDPE
Thermosoftening
Thermosetting

Question 6

LDPE

Answer 6

• has side branches so polymers do not line up in a crystalline structure.
• lower density than hdpe
• IMF between polymers are weak
• material is less strong, has a lower melting point than HDPE

Question 7

HDPE

Answer 7

• higher density than LDPE
• IMF between polymers = strong
• crystalline structure, polymers line up regularly
• higher melting point than LDPE

Question 8

Thermosoftening

Answer 8

• Melt when heated and can change shape, meaning theyre recyclable
• do not have covalent bonds between polymer molecules so can manouver over eachother when melted

Question 9

Thermosetting

Answer 9

• do not melt when heated
• resistant to high temps due to crosslinks between polymer molecules