C11 - Polymers

• Polymers are long chains of monomers joined together by covalent bonds.
• Monomers have carbon-carbon double bond. A bond is broken in the double bond and a monomer joins to the next one. This is addition polymerisation.
• Different monomers give different polymers with different properties.
• Polymers represented with repeat units.

  
• Condensation polymerisation - monomers don't need C-C double bond but they need two functional groups.
• Protein is example of condensation polymer: Polymers of amino acids. Amino acids contain 2 functional groups: carboxyl group and amino group. Carboxylic acid can react with amino group on another amino acid molecule to form a peptide bond. Reaction continuing creates a large polypeptide or protein.
• Proteins form molecules like enzymes, haemoglobin and wide variety of body tissue.
• The polymer of DNA is formed by nucleotide strands with bases twisted to form a double helix structure. The sequence of nucleotides in the DNA is a code for genes. The genetic information stored in a molecule of DNA is a set of instructions for each organism to stay alive and grow.
• Sugars can also form condensation polymers. e.g. Glucose can be stored as a polymer called glycogen. Plants make a polymer called cellulose to make their cell walls. Plants also make starch to store energy.