Polymers 3.3.12

Question 1

what are the 3 main types of condensation polymers

Answer 1

• Polypeptides
• Polyamides
• Polyesters

Question 2

what is condensation polymerisation

Answer 2

2 different monomers with at least 2 functional groups react together .
When they react a link is made , and water is eliminated

Question 3

where are polypeptides found

Answer 3

In proteins

Question 4

how are polyamides formed

Answer 4

By reacting diamines and dicarboxylic acids

Question 5

how are polyesters formed

Answer 5

By reacting a diol and a dicarboxylic acid together

Question 6

what link is formed when polyamides are formed

Answer 6

amide links

Question 7

why are dicarboxylic acids and diamines used to form polyamide

Answer 7

They have functional groups either side which allows a chain to be formed

Question 8

what is kevlar

Answer 8

a polyamide that is used in bulletproof vests , car tyres and some sports equipment as it is light weight but strong

Question 9

what is kevlar made from

Answer 9

Benzene - 1,4 - dicarboxylic acid and 1,4 - diaminobenzene

Question 10

what is Nylon 6,6

Answer 10

A polyamide that is used in ropes , carpets , clothing and parachute fabric

Question 11

what are the 2 examples of polyamides

Answer 11

nylon 6,6 and Kevlar

Question 12

what is nylon 6,6 made from

Answer 12

Hexanedioic acid and 1,6-diaminohexane

Question 13

what is the part inside the brackets of a polymer called and what are some rules

Answer 13

The repeating unit .
Do not draw the H2O from both the molecules .
Dont draw the Hydrogens on the ends

Question 14

what links are formed when polyesters are formed

Answer 14

ester links

Question 15

what is an example of a polyester

Answer 15

terylene

Question 16

what is terylene

Answer 16

polyester that is used in plastic drink bottles , sheeting and clothes.
acronym = PET

Question 17

what is terylene made from

Answer 17

benzene - 1,4- dicarboxylic acid and ethane -1,2-diol

Question 18

what is hydrolysis of condensation polymers

Answer 18

Condensation polymers can be hydrolysed to produce the original monomers . It’s just the reverse of polymerisation

Question 19

how do you determine the monomer units produced

Answer 19

-Break the bond in the middle of the amide or ester link of the repeat unit
- Add OH and H to each of the monomer units

Question 20

what causes the polar bonds in condensation polymers

Answer 20

Caused by C-O and C-N bonds that exist in the polymers

Question 21

why are condensation polymers stronger than addition polymers

Answer 21

• They’re more rigid and stronger
• Hydrogen bonds exist between the polymer chains as well as dipole - dipole and Van de waals forces

Question 22

what are synthetic polymers

Answer 22

Made from monomer units and used to make a range of items from plastic bottles , digital technology to non- stick coatings on pans

Question 23

what are properties of condensation polymers

Answer 23

• Polar and hence susceptible to attack from nucleophiles
• They are biodegradable and broken down by hydrolysis slowly

Question 24

what are properties of addition polymers

Answer 24

• They’re saturated molecules
• Normally non polar and hence are unreactive
• They are good when used in foods as they don’t react
• However they don’t degrade well in landfill

Question 25

when is using landfills useful for disposing plastics

Answer 25

• when plastics are too difficult to recycle • are too difficult to separate from other materials • There is not enough plastic to extract to make it economically viable

Question 26

what are the 3 ways of disposing plastics

Answer 26

- Using landfills - Incineration - Recycling

Question 27

what’s are disadvantages of using landfills to dispose plastic

Answer 27

•When waste decomposes in landfill it produces methane which is a greenhouse gas . • There is also a risk of water contamination from waste leaching • Not sustainable as large amounts of land is needed • Becoming increasingly expensive to use land for waste disposal

Question 28

when is incineration used in disposal of plastics

Answer 28

• if plastics can’t be recycled • the energy from burning it can be used to generate electricity

Question 29

what are disadvantages of using incineration when disposing plastics

Answer 29

- Burning plastics can release toxic fumes so these need to be monitored. Particularly chlorine based plastics e.g. PVC which produce harmful HCl gas when burned

Question 30

what can be used to neutralise acidic gases produced in incineration of disposing plastics

Answer 30

Flue gas scrubbers. They work by firing a base at the flue gases

Question 31

what’s the use of recycling plastics

Answer 31

-most plastics are made from crude oil which is a non-renewable resource - Recycling means reducing dependency on crude oil for making plastics , saving precious resources

Question 32

what’s another way to allow new production of plastics and other chemicals

Answer 32

Other plastics can be cracked into monomers to be used as an organic feedstock

Question 33

what are the disadvantages of recycling plastics

Answer 33

- Plastics can be contaminated with other materials when being recycled - It is difficult to recycle plastics due to the wide variety of different plastics - It is difficult to remake the original plastic from recycled material - Sorting and processing plastics to be recycled is expensive compared with incineration

Question 34

what are the advantages of recycling plastics

Answer 34

- It is cheaper to recycle plastics than make them from scratch - Less carbon dioxide is produced recycling plastics than incinerating them - Recycling reduces the reliance on landfill - Recycling preserves non renewable raw materials such as crude oil

Question 35

EQ : Explain why polyesters are biodegradable but polyalkenes are not biodegradable (2)

Answer 35

- polyesters are polar so susceptible to be attacked by nucleophiles - polyalkenes are non polar

Question 36

EQ : which polymer has hydrogen bonding between the polymer chains (1)

Answer 36

Kevlar

Question 37

Eq : Name the type of reaction that occurred between the polyester and the aq NaOH . Explain why the aq NaOH reacted with the polyester (3)

Answer 37

Hydrolysis Delta positive C in polyester reacts with OH-

Question 38

EQ : Compare recycling and burying in landfills as methods of disposing waste plastic . You should comment on advantages and disadvantages of both methods (3)

Answer 38

-landfill requires larger areas of land than recycling. -Landfill is relatively cheap, whereas collecting, sorting and processing plastics for recycling is expensive. - Recycling saves raw materials, whereas landfill requires new plastic to be made from new raw materials. -Landfill is technically easy, but recycling is technically difficult. - Methane is released from landfill as waste decomposes, so recycling produces fewer greenhouse gas emissions.