polymerisation and naturally occurring polymers

• plastics are made up of...

  long-chain molecules called polymers - they are usually carbon based and their monomers are often alkenes
• polymerisation

  a chemical reaction joining monomers in long chains to form a polymer
• what conditions does polymerisation need?

  high pressure and a catalyst
• additional polymers are made from...

  unsaturated monomers
• monomers that make up addition polymers have a ... bond

  double covalent
• what happens in addition polymerisation?

  a reaction where many unsaturated monomers join together to form polymer chains - the double bond opens up to form a bond to the next monomer (e.g. ethene forms poly(ethene))
• what is the product of addition polymerisation?

  a polymer only
• what do addition polymers contain?

  exactly the same type and number of atoms at the monomers that formed it - as the only product is the product only
• what affects the properties of a plastic?

  the monomer the polymer is made from
• how do you name polymers?

  add "poly" in front of the monomer's name in brackets
• how to draw a polymer from a monomer

  - replace the double bond of the alkene with a single bond

  - add trailing bonds

  - put brackets over the repeating unit and and 'n' outside the brackets to show it repeats
• condensation polymerisation


  a reaction in which monomers, which contain different functional groups, form ones between them to make polymer chains and with each new bond, a small molecule, such as water, is lost and formed as a by-product
• simplest type of condensation polymerisation

  contains two different types of monomer, each with two of the same functional groups
• condensation polymerisation products

  two monomers come together by losing a molecule. atoms from each monomer join together to make the molecule: commonly a H atom from one and a OH molecule from another form water. the two monomers then join together, making a polymer. the H atom and OH molecule form water
• differences between addition and condensation polymerisation

  addition polymerisation

  - only one monomer type containing a C=C bond

  - only one product formed

  - carbon-carbon double bond in monomer

  
  

  condensation polymerisation

  - two monomer types each containing two of the same functional groups OR one monomer type with two different functional groups

  - two types of product: the polymer and a small molecule (e.g. water)

  - two reactive groups on each monomer
• amino acids contain...

  two different functional groups - a basic amino group (NH2) and a carboxyl group (COOH)
• basic amino group


  NH2
• carboxyl group

  a -COOH group, found in organic acids.
• glycine

  the smallest and simplest amino acid possible
• proteins are polymers of...

  amino acids
• polypeptides

  a polymer of amino acids joined together by peptide bonds, via condensation polymerisation
• an amino group of an amino acid can react with ... to form a polymer chain


  the acid group of another and so on
• for every new peptide bond that is formed...

  a molecule of water is lost
• peptide bond


  the covalent chemical bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid
• one or more long chains of polypeptides are known as...

  proteins
• protein uses

  - enzymes work as catalysts

  - haemoglobin transports oxygen

  - antibodies form part of the immune system

  - majority of body tissue is made from proteins
• what gives proteins different properties and shapes?

  the order of amino acids
• DNA molecules are made from...

  two polymer chains of monomers called nucleotides
• DNA


  deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of chromosomes - it is the carrier of genetic information
• nucleotide

  a building block of DNA, consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group.
• nucleotide bases


  A, T, G, C

  - adenine, thymine, guanine, cytosine
• what do the bases of nucleotides do?

  pair up with each other and form cross links keeping the two strands of nucleotides together and giving the double helix structure - the order of the bases acts as a code for an organism's genes
• simple sugars can form...

  polymers
• sugars


  small carbohydrates - containing carbon, oxygen and hydrogen
• sugars can react together through...

  polymerisation to form larger polymers (e.g. starch, which living things use to store energy, and cellulose, which is found in plant cell walls)