Polymers

- plastics are made of very large covalently bonded molecules called polymers

- the large polymer molecules are made when mant monomers (small reactive molecules) join together

- the reaction between alkene monomers to form a polymer is called polymerisation

- in addition polymers, the repeating unit has the same atoms as the monomers, because when the C=C bond 'opens up' in polymerisation no ther molecule is formed in the reaction

- condensation polymerisation usually involves a small molecule released in the reaction, as the polymer forms

- the monomers used to make the simplest condensation polymers are usually 2 different monomers, with 2 same functional groups on each monomer

- polyesters are formed from the condensation polymerisation of a diol and a car dicarboxylic acid with H2O given off in the reaction

- simple carbohydrates (monosaccarides) polymerise to make polymers such as starch and cellulose

- proteins are polyemrs made from differnet amino acid monomers 

- amino acids have an acidic and a basic functional group in the small molecule

- amino acids react together during condensation polymerisation to make polypeptides and proteins made of long sequences of different monomers

- (Deoxyribonuclei acid) is made up from monomers called nucleotides

- nucleotides are based on the sugar deoxyribose, bonded to a phosphate group and a base, there are 4 possible bases that bond to the sugar

- a DNA molecule consists of 2 polymer strands (with sugars bonded to phosphate groups) intertwined into a double helix