ORGANIC CHEMISTRY - polymerisation

Question 1

what is condensation?

Answer 1

• small molecule eliminated ( usually H2O ) to form a larger molecule

Question 2

how many monomers are condensation polymers usually formed from?

Answer 2

2

Question 3

what properties do these monomers forming condensation polymers have?

Answer 3

Each has two functional groups

Question 4

examples of condensation polymers?

Answer 4

polyesters
polyamides
polypeptides

Question 5

linkage in polyester?

Answer 5

ester link

Question 6

what molecule is eliminated in the formation of polyester?

Answer 6

H2O

Question 7

what are the two monomers which form a polyester?

Answer 7

• diol
• dicarboxylic acid

Question 8

which monomers is Terylene made from?

Answer 8

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

Question 9

draw the repeating unit of terylene?

Answer 9

draw/ image on pmt

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

peptide/amide linkage

Question 12

which molecule is eliminated when polyamide is formed?

Answer 12

H2O

Question 13

what are the 2 monomers used to form a polyamide?

Answer 13

diamine and dicarboxylic acid

Question 14

examples of polyamides?

Answer 14

Nylon, Kevlar

Question 15

which monomers is Nylon-6,6 made from?

Answer 15

1,6-diaminohexane
Hexandioic acid

Question 16

draw the repeating unit of Nylon-6,6.

Answer 16

draw/image on pmt

Question 17

if you are making nylon in a lab, which monomers are you using and why? what molecule is eliminated?

Answer 17

hexane-1,6-di acyl chloride
rate of reaction much faster
Hcl

Question 18

what is kevlar used for?

Answer 18

bullet proof vests

Question 19

which monomers is kevlar made from?

Answer 19

1,4-diaminobenzne
Benzene-1,4-dicarboxylic acid

Question 20

draw repeating unit of kevlar?

Answer 20

draw/image on pmt

Question 21

why is kevlar so strong?

Answer 21

rigid chains and close packing of flat aromatic rings

Question 22

why are poly alkenes not biodegradable?

Answer 22

due to non polar C-H and C-C bonds

Question 23

why is it bad to burn poly(alkenes)?

Answer 23

CO2, CO, C soot released

Question 24

where do most poly(alkenes) end up?

Answer 24

land fill sites

Question 25

why can condensation polymers be broken down?

Answer 25

they have polar bonds

Question 26

how are condensation polymers broken down?

Answer 26

add water - hydrolysis

Question 27

why does hydrolysis not happen in normal conditions?

Answer 27

very slow in standard conditions

Question 28

4 stages of recycling polymers.

Answer 28

collected -> sorted -> melted -> reformed

Question 29

advantages of recycling polymers?

Answer 29

saves expense of crude oil and preserves a non-renewable resource
reduces land fill

Question 30

disadvantages of recycling polymers?

Answer 30

energy and manpower needed for collecting, sorting , melting = expensive
can only be done a limited number of times

Question 31

difference between addition and condensation polymerisation?

Answer 31

• condensation makes the polymer + eliminates small molecule
• addition polymerisation breaks c=c to form one product

Question 32

why do polyesters not show hydrogen bonding?

Answer 32

• all O-H bonds are removed during polymerisation