Polymers Flashcards
What does condensation polymerisation involve
The reaction between monomers containing two different functional groups with the loss of a small molecule
What can polyesters be formed from
The reaction of a carboxylic acid and an alcohol
What can polyesters be formed from beside a carboxylic acid and what would the other product be in this casee
Acyl chloride
Product would be HCl
How are the monomers joined together in polyesters
An Ester link
Polyesters: what is eliminated when the Ester link forms
A molecule of water
Polyesters: what is removed from the COOH group when the Ester link forms
OH group
Polyesters: what is removed from the OH group of the alcohol when the Ester link is formed
h atom
Uses of polyesters
Fibres
Polyesters: when can polyesters be formed from a single monomer
If it contains both an alcohol and a carboxylic acid group
Polyamides: what are polyamides formed from
The reaction of a dicarboxylic acid and a diamine
Polyamides: what are the monomers joined together by
An amide link
Polyamides: what is eliminated when the amide link forms
A molecule of water
Polyamides: what is removed from the acid grou owhen the link forms
OH
What is removed from the NH2 group of the amine when the amide rink forms
H ATOM
what is nylon 6,6 formed from
1,6 diaminohexane and hexane 1,6 dicarboxylic acid
uses of nylon 6 6
fibres, ropes, carpets, parachute silk
what is kevlar formed from
1,4 diamino benzene and benzene dicarboxylic acid
uses of kevlar
bullet proof material
what are the uses of kevlar due to
its strength
what is kevlars strength a result of
its structure
why can kevlar chains pack closely together
theyre planar
what does it mean that kevlar chains can pack closely together
intermolecular forces between neighbouring chains are stronger than in other polymers
what is the strongest intermolecular force present in kevlar
h bonding
where does hydrogen bond from in kevlar
delta + H atom of one amide link and lp O=C of another `
how can polyamides be formed
from a single monomer that contains both an amine and a carboxylic acid functional group
what is nylon 6 formed from
6-aminohexanoic acid
what monomers are polypeptide made from
amino acid monomers
why can amino acids react together to form a condensation polymer
each has an amine group and a carboxylic acid group
comparison of addition and condensation polymers: condensation polymerisation involves…
monomers joining together with the elimination of a small molecule such as water or HCl
comparison of addition and condensation polymers: in condensation the monomers must be either…
one molecule with 2 different functional groups/2 different molecules each with 2 functional groups
comparison of addition and condensation polymers: condensation polymers normally contain which kind of linkages
ester or amide
comparison of addition and condensation polymers: addition polymerisation involves
successive addition of a monomer to the growing polymer chain
comparison of addition and condensation polymers: the monomer in addition polymerisation is normally
an alkene RCH=CH2
comparison of addition and condensation polymers: the backbone of an addition polymer is
a continuous chain of carbon atoms
comparison of addition and condensation polymers: which kind of polymers are generally stronger and more rigid
condensation polymers are generally stronger and more rigid than addition
comparison of addition and condensation polymers: why are condensation polymers generally stronger and more rigid
IMF between polymer chains
- condensation: contain polar bonds
- polyesters: permanent dipole-dipole between chains
- polyamides: hydrogen bonds between chains
what does a repeating unit show
one of each monomer present in the polymer chain
why are addition polymers chemically inert
carbon skeleton consists of C-C single bonds
can addition polymers be hydrolysed
no
can polyamides and polyesters be hydrolysed
yes
hydrolysis
breaking a bond using water
why is a catalyst used in hydrolysis of polyamides and polyesters
reaction is slow so catalyst added to increase rate
what catalysts can be used for hydrolysis of polyamides and polyesters
aqueous strong acid/aqueous strong base
conditions for hydrolysis polyesters and polyamides
heat and reflux
why are addition polymers inert
the bonds between the repeat units are strong and non polar so are not susceptible to attack by nucleohiles
why are addition polymers non biodegradable and what does this mean
because they are inert
means they build up in waste tips and landfill sites
why can polyesters and polyamides be broken down by hydrolysis
because the bonds between the repeating units are polar so are susceptible to attack by nucleophiles
are polyesters and polyamides biodegradable
yes
what 3 methods are there for the disposal of polymers
- burying
- combustion
- sorting for reusing/recycling
advantage of burying
cheap and easy
disadvantage burying
requires areaas of land
waste releases methane and can release toxins (could run into water supplies) when decomposing
advantage combustion
produces heat energy
disadvantage combustion
- 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
advantage recycling
- polymers derived from crude oil- saves expensive resource by recycling
- saves energy from crude oil refining
- reduces landfill
- less CO2 than burning
disadvantage recycling
- 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
