Polymers Flashcards
(27 cards)
What are polymers made by joining together?
Lots of little molecules in long chains.
What are polymers?
Substances of high average relative molecular mass made by joining up lots of small repeating units called monomers.
What kind of bonds do monomers in addition polymers have?
A double covalent bond
How do unsaturated monomers form polymers?
- They open up their carbon-carbon double bonds and join together to form polymer chains
- called addition polymerisation.
What happens to ethene during addition polymerisation?
Ethene (C2H4) becomes poly(ethene) under pressure and with a catalyst.
What does “n” represent in polymerisation?
Any number; it means you start with lots of monomer molecules.
How is propene polymerised?
Propene becomes poly(propene) under pressure and with a catalyst.
How do you name a polymer?
- Take the name of the monomer
- Put it in brackets
- Add the prefix “poly”. E.g., propene becomes poly(propene).
How do you write the formula of a polymer?
Put the monomer formula in brackets followed by a little ‘n’.
How do you draw the displayed formula of an addition polymer?
- Join the carbons in a row with no double bonds
- Put brackets around the repeating bit
- Draw a bond from each carbon through the brackets
- Add an ‘n’ after it.
How do you find the monomer from a polymer?
- Draw the repeating unit
- Remove the bonds through the brackets
- Add a double bond between the carbons.-
What is the monomer and polymer for chloroethene?
Chloroethene becomes poly(chloroethene).
What is the monomer and polymer for tetrafluoroethene?
Tetrafluoroethene becomes poly(tetrafluoroethene).
Why are most addition polymers hard to get rid of?
They are inert because of strong carbon-carbon bonds -> they don’t react easily.
Why don’t they biodegrade easily?
It takes a very long time for bacteria and organisms to break them down.
Why is burning plastics not a great solution?
It can release toxic gases
What is the best way to deal with polymers?
Reuse them as much as possible and recycle them if you can.
What is condensation polymerisation?
A reaction involving two different types of monomers with at least two functional groups, forming bonds between them and losing small molecules like water.
What are polyesters?
Polymers that contain ester links joining repeating units.
How do polyesters form?
When dicarboxylic acid monomers and diol monomers react together.
What functional groups are in the monomers used to make polyesters?
Dicarboxylic acids have -COOH groups, and diols have -OH groups.
What happens when carboxylic acid and alcohol groups react?
An ester link is formed and water is lost.
What kind of polymer is a polyester?
A condensation polymer
What is an example of a polyester reaction?
Ethanediol + ethanedioic acid → Poly(ethyl ethanoate) + water
