POLYMERS

Question 1

Name four differences between polymers and small molecules

Answer 1

1. Aggregated states - polymers cant be gaseous
2. Dissolution - polymers swell first
3. Solution properties - polymers are more vicious
4. Mechanical properties - polymers are able to show elasticity and reversible

Question 2

Define configuration

Answer 2

Order of polymers due to its chemical bonds

Question 3

Name the three states of a amorphous polymers

Answer 3

1. Glassy
2. Rubbery
3. Liquid

Question 4

What is the Tg value

Answer 4

• When polymer goes from glassy (hard) to rubbery (soft)
• Different value for each polymer

Question 5

Below Tg polymers are ..
Above Tg polymers are ..

Answer 5

Below they are hard and glassy
Above they are soft and elastic

Question 6

Describe the stages of dissolution of a polymer

Answer 6

1. Diffusion of solvent molecules into the polymer
2. Swollen gel
3. Dissolution of the gel

Question 7

Describe the factors effecting solubility of a polymer

Answer 7

1. Polymer-solvent interactions - chemical similarity more likely to solubilise
2. Presence of cross links - don’t dissolve
3. Molecular weight - smaller macromolecules dissolve faster
4. Temperature

Question 8

Describe the four ways to make polymers

Answer 8

1. Addition polymerisation - Breaking of C=C, typical one
2. Ring open polymerisation - requires heat and catalyst
3. Step growth polymerisation - forms polymer and biproduct mainly water
4. Addition copolymerisation - made of two different monomers