MacromoleculesMacromoleculesSynthetic PolymersSynthetic Polymers

MacromoleculesMacromolecules

Macromolecules are large molecules Macromolecules are large molecules built up from many small repeating built up from many small repeating units (monomers) joined together by units (monomers) joined together by covalent bondingcovalent bonding

Different macromolecules are made Different macromolecules are made up of different units and/or different up of different units and/or different linkageslinkages

Generally, 2 types of macromolecules Generally, 2 types of macromolecules – synthetic and natural– synthetic and natural

DefinitionsDefinitions

A monomer is a small molecule that A monomer is a small molecule that may be covalently bonded to other may be covalently bonded to other monomers to form a polymermonomers to form a polymer

A polymer is the macromolecule A polymer is the macromolecule formed when monomers are covalently formed when monomers are covalently bonded to form a long chain of bonded to form a long chain of moleculemolecule

Polymerisation is the process whereby Polymerisation is the process whereby a large number of small molecules a large number of small molecules (monomers) join together to form a (monomers) join together to form a macromoleculemacromolecule

Synthetic polymersSynthetic polymers

PolyethenePolyethene Polyvinyl chloridePolyvinyl chloride TeflonTeflon PolystyrenePolystyrene PerspexPerspex NylonNylon TeryleneTerylene

Addition PolymerisationAddition Polymerisation

Addition polymerisation occurs Addition polymerisation occurs when monomer units join together when monomer units join together by breaking double or triple bonds by breaking double or triple bonds without losing any molecules or without losing any molecules or atomsatoms

Eg. Alkenes undergo addition Eg. Alkenes undergo addition polymerisation whereby the double polymerisation whereby the double bonds in alkenes are changed to bonds in alkenes are changed to single bondssingle bonds

Formation of polyethene Formation of polyethene from ethenefrom ethene

n can be between 10 000 and 30 000

More addition polymersMore addition polymers

Name & formula of Name & formula of monomermonomer

Name & formula of Name & formula of polymerpolymer

PropenePropene PolypropenePolypropene

ChloroetheneChloroethene

(vinyl chloride)(vinyl chloride)PolychloroethenePolychloroethene

Polyvinyl chloridePolyvinyl chloride

TetrafluoroetheneTetrafluoroethene PolytetrafluoroethenPolytetrafluoroethenee

TeflonTeflon

PhenylethenePhenylethene

StyreneStyrenePolyphenylethenePolyphenylethene

PolystyrenePolystyrene

Condensation Condensation PolymerisationPolymerisation

Condensation polymerisation Condensation polymerisation occurs when monomer units join occurs when monomer units join together by eliminating a small together by eliminating a small molecule, like water, to produce a molecule, like water, to produce a polymerpolymer

2 main types of condensation 2 main types of condensation polymers – polyamides and polymers – polyamides and polyesters polyesters

Formation of NylonFormation of Nylon Made from dicarboxylic acid and Made from dicarboxylic acid and

diaminediamine

H-O O-H H H

AMIDE LINKAGE –CONH –

Formation of TeryleneFormation of Terylene

Made from dicarboxylic acid and Made from dicarboxylic acid and dioldiol

Benzene-1,4-dicarboxylic acid and Benzene-1,4-dicarboxylic acid and ethane-1,2-diolethane-1,2-diol

H-O O-H H H

ESTER LINKAGE –COO –

Uses of synthetic Uses of synthetic polymerspolymers

NameName UsesUses

PolyethenPolyethenee

To make plastic bags, cling To make plastic bags, cling filmfilm

NylonNylon To make clothing, fishing line, To make clothing, fishing line, parachutesparachutes

TeryleneTerylene To make clothingTo make clothing

PVCPVC To make insulator for cables, To make insulator for cables, plastic raincoatsplastic raincoats

PolystyrenPolystyrenee

To make polystyrene To make polystyrene disposable boxes, light-weight disposable boxes, light-weight packagingpackaging

TeflonTeflon For coating cooking utensilsFor coating cooking utensils

Pollution caused by non-Pollution caused by non-biodegradable plasticsbiodegradable plastics

Plastics are relatively cheap, easily Plastics are relatively cheap, easily shapedshaped

Light, tough, waterproof and durableLight, tough, waterproof and durable However, cannot be decomposed by However, cannot be decomposed by

bacteria in the soilbacteria in the soil Disposal usually by burning, and Disposal usually by burning, and

possibly produce poisonous gasespossibly produce poisonous gases Biodegradable plastics are required Biodegradable plastics are required

to solve the problemsto solve the problems

MacromoleculesMacromoleculesNatural MacromoleculesNatural Macromolecules

Examples of natural Examples of natural macromoleculesmacromolecules

ProteinsProteins Fats Fats CarbohydratesCarbohydrates They are the main constituents of They are the main constituents of

food but with different units food but with different units

ProteinsProteins

Built up from Built up from units of amino units of amino acidsacids

Proteins have the Proteins have the same amide same amide linkages as nylon linkages as nylon but with different but with different unitsunits

Fats and OilsFats and Oils

Built up from glycerol and long-Built up from glycerol and long-chain carboxylic acids (fatty acids)chain carboxylic acids (fatty acids)

Fats are esters possessing the Fats are esters possessing the same ester linkages as Terylene same ester linkages as Terylene but with different unitsbut with different units