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Flashcards in Polymers Deck (55)
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1
Q

What does condensation polymerisation involve

A

The reaction between monomers containing two different functional groups with the loss of a small molecule

2
Q

What can polyesters be formed from

A

The reaction of a carboxylic acid and an alcohol

3
Q

What can polyesters be formed from beside a carboxylic acid and what would the other product be in this casee

A

Acyl chloride

Product would be HCl

4
Q

How are the monomers joined together in polyesters

A

An Ester link

5
Q

Polyesters: what is eliminated when the Ester link forms

A

A molecule of water

6
Q

Polyesters: what is removed from the COOH group when the Ester link forms

A

OH group

7
Q

Polyesters: what is removed from the OH group of the alcohol when the Ester link is formed

A

h atom

8
Q

Uses of polyesters

A

Fibres

9
Q

Polyesters: when can polyesters be formed from a single monomer

A

If it contains both an alcohol and a carboxylic acid group

10
Q

Polyamides: what are polyamides formed from

A

The reaction of a dicarboxylic acid and a diamine

11
Q

Polyamides: what are the monomers joined together by

A

An amide link

12
Q

Polyamides: what is eliminated when the amide link forms

A

A molecule of water

13
Q

Polyamides: what is removed from the acid grou owhen the link forms

A

OH

14
Q

What is removed from the NH2 group of the amine when the amide rink forms

A

H ATOM

15
Q

what is nylon 6,6 formed from

A

1,6 diaminohexane and hexane 1,6 dicarboxylic acid

16
Q

uses of nylon 6 6

A

fibres, ropes, carpets, parachute silk

17
Q

what is kevlar formed from

A

1,4 diamino benzene and benzene dicarboxylic acid

18
Q

uses of kevlar

A

bullet proof material

19
Q

what are the uses of kevlar due to

A

its strength

20
Q

what is kevlars strength a result of

A

its structure

21
Q

why can kevlar chains pack closely together

A

theyre planar

22
Q

what does it mean that kevlar chains can pack closely together

A

intermolecular forces between neighbouring chains are stronger than in other polymers

23
Q

what is the strongest intermolecular force present in kevlar

A

h bonding

24
Q

where does hydrogen bond from in kevlar

A

delta + H atom of one amide link and lp O=C of another `

25
Q

how can polyamides be formed

A

from a single monomer that contains both an amine and a carboxylic acid functional group

26
Q

what is nylon 6 formed from

A

6-aminohexanoic acid

27
Q

what monomers are polypeptide made from

A

amino acid monomers

28
Q

why can amino acids react together to form a condensation polymer

A

each has an amine group and a carboxylic acid group

29
Q

comparison of addition and condensation polymers: condensation polymerisation involves…

A

monomers joining together with the elimination of a small molecule such as water or HCl

30
Q

comparison of addition and condensation polymers: in condensation the monomers must be either…

A

one molecule with 2 different functional groups/2 different molecules each with 2 functional groups

31
Q

comparison of addition and condensation polymers: condensation polymers normally contain which kind of linkages

A

ester or amide

32
Q

comparison of addition and condensation polymers: addition polymerisation involves

A

successive addition of a monomer to the growing polymer chain

33
Q

comparison of addition and condensation polymers: the monomer in addition polymerisation is normally

A

an alkene RCH=CH2

34
Q

comparison of addition and condensation polymers: the backbone of an addition polymer is

A

a continuous chain of carbon atoms

35
Q

comparison of addition and condensation polymers: which kind of polymers are generally stronger and more rigid

A

condensation polymers are generally stronger and more rigid than addition

36
Q

comparison of addition and condensation polymers: why are condensation polymers generally stronger and more rigid

A

IMF between polymer chains

  • condensation: contain polar bonds
  • polyesters: permanent dipole-dipole between chains
  • polyamides: hydrogen bonds between chains
37
Q

what does a repeating unit show

A

one of each monomer present in the polymer chain

38
Q

why are addition polymers chemically inert

A

carbon skeleton consists of C-C single bonds

39
Q

can addition polymers be hydrolysed

A

no

40
Q

can polyamides and polyesters be hydrolysed

A

yes

41
Q

hydrolysis

A

breaking a bond using water

42
Q

why is a catalyst used in hydrolysis of polyamides and polyesters

A

reaction is slow so catalyst added to increase rate

43
Q

what catalysts can be used for hydrolysis of polyamides and polyesters

A

aqueous strong acid/aqueous strong base

44
Q

conditions for hydrolysis polyesters and polyamides

A

heat and reflux

45
Q

why are addition polymers inert

A

the bonds between the repeat units are strong and non polar so are not susceptible to attack by nucleohiles

46
Q

why are addition polymers non biodegradable and what does this mean

A

because they are inert

means they build up in waste tips and landfill sites

47
Q

why can polyesters and polyamides be broken down by hydrolysis

A

because the bonds between the repeating units are polar so are susceptible to attack by nucleophiles

48
Q

are polyesters and polyamides biodegradable

A

yes

49
Q

what 3 methods are there for the disposal of polymers

A
  • burying
  • combustion
  • sorting for reusing/recycling
50
Q

advantage of burying

A

cheap and easy

51
Q

disadvantage burying

A

requires areaas of land

waste releases methane and can release toxins (could run into water supplies) when decomposing

52
Q

advantage combustion

A

produces heat energy

53
Q

disadvantage combustion

A
  • increases levels CO2
  • incomplete combustion- CO or C particles
  • burning polystyrene under certain conditions can lead to toxic styrene vapour
  • burning chlorinated polymers- HCl gas needs to be removed
54
Q

advantage recycling

A
  • polymers derived from crude oil- saves expensive resource by recycling
  • saves energy from crude oil refining
  • reduces landfill
  • less CO2 than burning
55
Q

disadvantage recycling

A
  • plastics need to be collected, transported and sorted- energy, manpower- expensive
  • can be technically difficult to recycle some plastics
  • often cant remake plastic started with- have to make something else