SC24 Polymers Flashcards
Define polymer
substances of high average relative molecular mass made by joining up lots of small repeating units called monomers
How does ethene become poly(ethene)?
Ethene opens up its double bonds to form polymer chains
Define addition polymerisation
One of the bonds in each C=C bond breaks and forms a bond with the adjacent monomer with the polymer being formed containing single bonds
Starch is a polymer
Starch and cellulose are large, complex molecules which are made up of smaller units of carbohydrates, known as sugars, joined together in a long chain
Proteins are a polymer
Amino acid monomers form polymers known as proteins via condensation polymerisation
Define condensation polymerisation
involves two different types of monomers that react together making polymer chains
Define a polyester
Polyesters form when dicarboxylic acid monomers and diol monomers react together
How is a molecule of water lost from an ester link?
When a carboxylic acid group reacts with an alcohol group, it forms an ester link. Each time an ester link is formed, a molecule of water is lost
Properties / Uses of poly(ethene)
Properties - flexible, insulator, cheap
Uses - plastic bags, bottles, wire insulation
Properties / Uses of poly(propene)
Properties - flexible, strong, tough, mouldable
Uses - crates, furniture, ropes
Properties / Uses of poly(chloroethene) PVC
Properties - tough, cheap
Uses - window frames, water pipes
Properties / Uses of poly(tetrafluoroethene) PTFE
Properties - unreactive, tough, non-stick
Uses - non-stick pans, waterproof clothing
