6.2.3: Polyesters and polyamides Flashcards
What is condensation?
Small molecule eliminated (usually H2O) to form
a larger molecule
How many monomers are condensation polymers
usually formed from?
2
What properties do these monomers forming
condensation polymers have?
Each has two functional groups
Examples of condensation polymers?
Polyesters
Polyamides
Polypeptides
What is the linkage in a polyester?
O=C-O -the ester linkage
What molecule is eliminated in formation of a
polyester?
water
What are the two monomers which form a polyester
(generic names and structures)?
Diol and dicarboxylic acid or a molecule with both alcohol and a carboxylic acid functional groups
Which monomers is Terylene made from?
Benzene-1,4-dicarboxylic acid
Ethane-1,2-diol
What is Terylene used for?
As a fibre for making clothes
What is the linkage in a polyamide?
C=O H-N (C single bonded to O as well)
Which molecule is eliminated when a polyamide is
formed?
water
What are the two monomers used to form a polyamide (generic names and structures)?
Diamine and dicarboxylic acid
Examples of polyamides?
Nylon, Kevlar
Which monomers is Nylon-6,6 made from?
1,6 diaminohexane
Hexanedioic acid
If you are making Nylon in the lab, what monomers would you use and why? What molecule is eliminated?
Use hexane-1,6-diacyl chloride as the rate of reaction is much faster. HCl is eliminated
What is Kevlar used for?
In body armour (bullet proof vests, stab vests),
helmets (e.g. F1 drivers’), oven gloves
Which monomers make up Kevlar?
1,4-diaminobenzene
Benzene-1,4-dicarboxylic acid
Why are poly(alkenes) not biodegradable?
Non-polar C-H and C-C bonds
Why is it bad to burn poly(alkenes)?
Releases CO2, CO, C (soot) and other toxic chemicals from monomers
Where do most poly(alkenes) end up?
Landfill sites
Why can condensation polymers be broken down?
They have polar bonds
How are condensation polymers broken down?
Hydrolysis (opposite of condensation)
What is the difference between addition and
condensation polymerisation?
Condensation makes the polymer and eliminates
a small molecule; addition polymerisation breaks
C=C to form only one product (just the polymer).
Explain hydrogen bonding between polyamides.
Both C=O and N-H are polar bonds, as N’s electronegativity >
H’s and O’s electronegativity > C’s.
Hydrogen bonding between H + and O - in different
molecules
Uses the lone pair of electrons on the O atom
Why do polyesters not show hydrogen bonding?
All O-H bonds are removed during polymerisation
