Polymers

Question 1

Polymers

Answer 1

1. Forms plastic and synthetic Fibers
2. Long Chains formed from simple molecules (Monomers) joined together
3. Monomers undergo reaction to link together and become a polymer by polymerisation

Question 2

Types of Polymerisation Reaction

Answer 2

1. Addition Polymerisation

2. Condensation Polymerisation

Question 3

Addition Polymerisation

Answer 3

1. Monomers must be Alkenes (Double Bonds)
2. Double bond is broken and allows for addition of the next monomer unit
3. The chain length can be tens of thousands long

Question 4

Condensation Polymerisation

Answer 4

1. Formed through a condensation reaction where molecules (Monomers) join together-losing small molecules as by-product (often water)

Question 5

Thermosetting

Answer 5

1. Thermosetting Plastic cannot be removed
2. They don’t melt, they char
3. Formed by a condensation reaction

Question 6

Thermoplastic (Linear)

Answer 6

1. Are polymers that form as long chains
2. Long Chains = Large molecules with intermolecular Bonding
3. Held by dispersion forces
4. Heating the dispersion force can break and soften the material to mold into a new shape

Question 7

Properties of the polymers are affected by

Answer 7

1. Choice of monomer
2. Degree of branching
3. Degree of Crystallinity
4. Length of polymer chain
5. Addition of Plasticisers

Question 8

Choice of Monomer

Answer 8

1. An Addition polymer needs monomers with carbon double bonds.
2. Condensation polymer has a molecule that’s eliminated in the Polymerisation Reaction
3. Monomers can be the same or different

Question 9

Degree of Crystallinity

Answer 9

Is how regularly aligned the polymer chains are; the more aligned the higher the degree of crytallinity

Question 10

Additives

Answer 10

1. Plasticizers - soften and increase flexibility
2. UV stabilisers – absorb UV rays to prevent polymer breakdown
3. flame retardants – reduce the likelihood of polymers burning
4. Dyes – add color and/or patterns

Question 11

Branching

Answer 11

With polyethylene there are two types
Low density (LDPE) and high density (HDPE)
Each are polyethylene but are produced under different conditions to have different properties and uses
LDPE is produced under higher pressure (20000psi) and moderate temperature (200C)
HDPE is produced under low pressure (200psi) and lower temperature (150C)

Question 12

Advantages of LDPE

Answer 12

1. High Elasticity/ Flexibility
2. Soft
3. Light Weight= Energy efficient
   4.

Question 13

Disadvantages of LDPE

Answer 13

1. Clear Plastic
2. Flimsy and Thin
3. Less strength then HDPE

Question 14

Applications of LDPE

Answer 14

used in jobs that require more elasticity but limited strength

Question 15

Advantages of HDPE

Answer 15

1. Rigid and Firm
2. Puncture Resistant
3. Resistant to weather conditions

Question 16

Disadvantages of HDPE

Answer 16

1. Thicker Material
2. Less Flexible
3. Require more energy to produce

Question 17

Applications of HDPE

Answer 17

Jobs that require extra strength, but less flexibility