What type of polymer forms when monomers join together with the elimination of a small molecule?
Condensation polymer
Small molecules such as water or HCl are released during polymer formation.
What type of monomers react together to form polyesters?
Dicarboxylic acids and diols
The reaction forms ester linkages between repeating units.
Fill in the blank:
The linkage formed in polyesters is called an _______ linkage.
ester
It has the functional group –COO–.
True or False:
Polyamides are formed by reactions between dicarboxylic acids and diamines.
True
The reaction forms amide (–CONH–) linkages in the polymer chain.
What type of linkage is present in polyamides such as nylon?
Amide linkage
The functional group is –CONH–.
True or False:
Terylene is an example of a polyester.
True
It is formed from benzene-1,4-dicarboxylic acid and ethane-1,2-diol.
Fill in the blank:
Nylon 6,6 is an example of a _______ polymer.
polyamide
Its repeating units are connected by amide bonds.
What type of molecules can polymerise by condensation to form polyamides directly?
Amino acids
Each molecule contains both amine and carboxylic acid groups.
True or False:
Condensation polymers usually form by eliminating molecules such as water.
True
The loss of a small molecule occurs during bond formation.
Fill in the blank:
Strong intermolecular forces between polyamide chains include _______ bonding.
hydrogen
The –CONH– groups allow hydrogen bonds to form.
What type of intermolecular forces mainly hold polyester chains together?
Dipole–dipole interactions
These arise from the polar ester groups in the chain.
Why do condensation polymers such as Kevlar have high strength?
Strong intermolecular forces
Hydrogen bonding and rigid structures increase mechanical strength.
What type of polymers are formed from alkene monomers and are generally non-biodegradable?
Polyalkenes
Examples include poly(ethene) and poly(propene).
Why are polyalkenes resistant to biodegradation?
Chemically inert backbone
Their chains contain only strong C–C and C–H bonds.
Fill in the blank:
Polyalkenes are difficult to break down because their polymer chains lack _______ groups.
functional
Functional groups are needed for hydrolysis reactions.
True or False:
Polyesters can be broken down by hydrolysis.
True
Water can break the ester linkage in the polymer chain.
What type of polymers contain ester linkages that allow hydrolysis to occur?
Polyesters
The –COO– linkage can react with water.
True or False:
Polyamides are biodegradable because their amide bonds can be hydrolysed.
True
Water can break the –CONH– linkage under suitable conditions.
Fill in the blank:
The linkage present in polyamides that can be hydrolysed is the _______ bond.
amide
This bond can be broken by hydrolysis.
Why can condensation polymers be broken down by hydrolysis?
Reactive linkages
Ester and amide bonds react with water.
True or False:
Recycling polymers reduces the need for new raw materials.
True
It conserves fossil fuels and reduces waste.
Fill in the blank:
Breaking polymers down by heating in the absence of oxygen is called _______.
pyrolysis
This process can produce smaller hydrocarbons.
What is one disadvantage of burning polymers as a disposal method?
Toxic gases
Combustion can release harmful gases such as CO or HCl.
Why are biodegradable polymers environmentally beneficial?
Break down naturally
Microorganisms can degrade them into smaller, less harmful substances.