Polymers

Question 0

How are polymers formed?

Answer 0

Lots of small molecules called monomers join together under high pressure with a catalyst - called polymerisation.

Question 1

What is a polymer?

Answer 1

Plastic made from long chain molecules

Question 2

Explain how addition polymers are made from unsaturated monomers - addition polymerisation.

Answer 2

Monomers have a double covalent bond.
molecules with at least one double covalent bond between carbon atoms are UNSATURATED.
Molecules with no double bond are SATURATED COMPOUND
Lots of unsaturated monomer molecules (alkenes) open their double bonds to join in a polymer chain.

Question 3

What is it that determines the properties of plastics?

Answer 3

Forces between polymer chains

Question 4

Describe plastics with weak forces.

Answer 4

Polymer chains slide over each other
Plastics stretch easily
Have low melting point

Question 5

Describe plastics with strong forces

Answer 5

May have covalent bonds between polymer chains or cross linking bridges - stay parallel
High melting points
Rigid
Can’t be stretched