Polymers

Question 1

What is a condensation reaction ?

Answer 1

When a smaller molecule (typically H2O) is eliminated to form a larger molecule

Question 2

How many monomers are condensation polymers usually formed from ?

Answer 2

Two

Question 3

What are some examples of condensation polymers ?

Answer 3

Polyesters
Polyamides
Polypeptides

Question 4

What is the linkage in a polyester ?

Answer 4

COOR (C=O C-O)

Question 5

What molecule is eliminated in the formation of a polyester ?

Answer 5

H2O

Question 6

What are the two molecules that form a polyester ?

Answer 6

•Two molecules with both carboxylic acid and alcohol functional groups (both ends)
•Eg. Diol and dicarboxylic acid

Question 7

What is the generic repeating unit for a polyester ?

Answer 7

— CO — R — CO — O — R’ — O —

Question 8

What monomers is Terylene made of ?

Answer 8

•Benzene 1-4dicarboxylic acid
•Ethane-1,2-diol.

Question 9

What is the repeating unit of terylene ?

Answer 9

• CO - C6H6 - CO - O - CH2 - CH2 - O -

Question 10

What is terylene used for ?

Answer 10

As a fibre for making clothes

Question 11

What is the linkage in a polyamide ?

Answer 11

— CO —NH —

Question 12

What molecule is eliminated when a polyamide is formed ?

Answer 12

H2O

Question 13

What are the two monomers used to form a polyamide ?

Answer 13

•Diamine
•Dicarboxylic acid

Question 14

What are examples of polyamides ?

Answer 14

Nylon and Kevlar

Question 15

What are the monomers of Nylon-6,6 ?

Answer 15

•1,6-diaminohexane
•Hexandioic acid

Question 16

What is the repeating unit of Nylon-6,6 ?

Answer 16

-NH-(CH2)4-NH-CO-(CH2)4-CO-

Question 17

If you are making Nylon in a lab what monomers would you use and why ?

Answer 17

•Hexane-1,6-diacyl chloride as it’s rate of reaction is far higher
•HCl is eliminated.

Question 18

What is Kevlar used for ?

Answer 18

In body armour

Question 19

What monomers is Kevlar made from ?

Answer 19

•1,4-diaminobenzene
•Benzene-1,4-dicarboxylic acid.

Question 20

What is the repeating unit of Kevlar ?

Answer 20

— NH — C6H6 — NH — CO — C6H6 — CO —

Question 21

Why is Kevlar so strong ?

Answer 21

Rigid chains and close packing of flat aromatic rings

Question 22

What are polypeptides ? What is the linkage ?

Answer 22

It’s the same linkage as polyamides (-CO-NH-), but is made from just one amino acid monomer

Question 23

Draw a dipeptide

Answer 23

H2N-CHR-CO-NH-CHR’-COOH

Question 24

Why are polyalkenes not biodegradable ?

Answer 24

None of its bonds are polar

Question 25

Why is it bad to combust polyalkenes ?

Answer 25

Release CO2, CO and C - toxic chemicals

Question 26

Where do most polyalkenes end up ?

Answer 26

Landfill sites

Question 27

Why can condensation polymers be broken down ?

Answer 27

They have polar bonds

Question 28

How are condensation polymers broken down ?

Answer 28

Hydrolysis

Question 29

Why is hydrolysis not a viable way of breaking down polymers on normal conditions ?

Answer 29

Very slow rate of reaction

Question 30

What are the four stages needed when recycling polymers ?

Answer 30

Collected -> sorted -> melted -> reformed

Question 31

What are the advantages of recycling polymers ?

Answer 31

•Saves expensive crude oil and a non renewable recourse
•Reduces landfill

Question 32

What are the disadvantages of recycling polymers ?

Answer 32

•Energy and manpower are needed, making it expensive
•Can only be done a limited number of times

Question 33

How do you draw a polymer ?

Answer 33

Draw with square brackets, n on outside and trailing bonds

Question 34

What does draw the repeating unit of a polymer mean

Answer 34

Just draw the molecule, no trailing bonds, brackets or n

Question 35

What is the difference between addition and condensation polymerisation ?

Answer 35

•Condensation makes the polymer and eliminates a small molecule
•Addition polymerisation breaks C=C to form only one product

Question 36

Why do all polyesters not show hydrogen bonding

Answer 36

All OH bonds are removed during polymerisation