O2: 29 Polymerisation Flashcards
Condensation polymers are formed by reactions between…?
- dicarboxylic acids and diols
- dicarboxylic acids and diamines
- amino acids
What are the repeating units and linkages in Terylene (PET)? Draw it.
Benzene-1,4-dicarboxylic acid
+
ethane-1,2-diol
ester links
What are the repeating units and linkages in nylon 6,6? Draw it.
1,6-diaminohexane
+
hexanedioic acid
amide links
What are the repeating units and linkages in Kevlar? Draw it.
1,4-diaminobenzene
+
benzene-1,4-dicarboxylic acid
amide links
What are the typical uses of Terylene (PET)?
Used in plastic bottles, clothing, sheets, and sails.
What are the typical uses of nylon 6,6?
Used to make clothing, carpet, rope, airbags, and parachutes.
What are the typical uses of Kevlar?
Used in bulletproof vests, boat construction, car tyres, and lightweight sports equipment.
What are the intermolecular forces between condensation polymers?
They have polar bonds, e.g. C-N and C-O.
Therefore, there are van der Waals, permanent dipole-dipole forces, and hydrogen bonds between polymer chains.
What are the features of polyalkenes?
They are chemically inert and non-biodegradable.
What can polyesters and polyamides be broken down by?
Are they biodegradable?
Broken down by hydrolysis so are biodegradable.
What are the advantages and disadvantages of disposing of polymers in landfill?
+ cheap and easy
- requires areas of land
- as the waste decomposes, methane can be released
- leaks can contaminate water supplies
What are the advantages and disadvantages of disposing of polymers by incineration?
+ heat is used to generate electricity
- needs to be carefully controlled to reduce the release of toxic gases
- waste CO2 and H2O contributes to global warming
What are the advantages and disadvantages of disposing of polymers by recycling?
+ reduces amount of waste going into landfill
+ saves raw materials
+ recycling is cheaper than making polymers from scratch.
+ produces less CO2 emissions than incineration
- technically difficult
- collecting, sorting, and processing the plastic is more expensive than landfill/ incineration
- can’t remake original plastic
- plastic can be easily contaminated
What are the different ways of disposing of polymers by recycling?
Some polymers can be melted and remoulded.
Some can be cracked into monomers, which are used to make more plastics or other chemicals.
Why can polyesters and polyamides be hydrolysed but polyalkenes can’t?
They have polar bonds, making them open to nucleophilic attack.
