• Monomers with double bonds (unsaturated) • Addition reaction • Repeating units joined together by covalent bonds without loss of any molecule

Polymerization

Polymerization • Polymers are long chains molecules • Joining large number of repeating units called monomers • Known as plastics • Addition and condensation polymerization

http://www.fimmtech.com/index.php?id=6&subid=30

• Monomers with different functional gps. • Condensation reaction • Repeating units joined together by covalent bonds with a loss of water/HCI molecule • Polyester – carboxyl and hydroxyl gp join together (ester link) • Polyamide - carboxyl and amine gp join together (amide link)

Addition polymerization Condensation polymerization

Polymerization

Examples Addition Polymers • Polyethene (polythene), (PE) • Polyvinyl chloride, poly(chloroethene), (PVC) • Polypropene (PP) • Poly (tetrafluoroethene) , PTFE • Polystyrene (PS)

Examples Condensation Polymers • Polyamide, Nylon 6.6 • Polyester, Terylene, PET

Ethene monomers - addition polymerization- polyethene, (PE)

http://www.impexgp.com/product.html

http://www.ehow.com/facts_6935785_difference-ldpe-hdpe.html

http://recyclecare.com.au/en/Grade_PP.html

Propene monomers - addition polymerization – polypropene, (PP)

Addition Polymerization

High pressure

1200atm

High Temp

200C

http://www.impexgp.com/product.html

http://businessbarbados.com/green-business/the-dangers-of-polystyrene/

http://shop.ch.interapp.net/index.php?cat=KAT01&lang=ENG

http://www.ehow.com/facts_6935785_difference-ldpe-hdpe.html

http://recyclecare.com.au/en/Grade_PP.html

Addition Polymerization

Chloroethene monomers - addition polymerization – poly(chloroethene), (PVC)

Styrene/phenylethene monomers - addition polymerization – polystyrene, (PS)

Tetrafluoroethene monomers – poly(tetrafluoroethene), Teflon, (PTFE)

Addition Polymerization

H H | | C = C | | H H

H H | | C = C | | H CI

H H | | C = C | | H CH3

F F | | C = C | | F F

+

H H | | C = C | | H H

H H | | C = C | | H H

H H | | C = C | | H H

H H | | C = C | | H H

H H | | C = C | | H CI

H H | | C = C | | H CI

H H | | C = C | | H CI

H H | | C = C | | H CI

H H | | C = C | | H CH3

H H | | C = C | | H CH3

H H | | C = C | | H CH3

H H | | C = C | | H CH3

F F | | C = C | | F F

F F | | C = C | | F F

F F | | C = C | | F F

F F | | C = C | | F F

Addition Polymerization - No loss of molecule, long chain formed, Unsaturated monomer to Saturated polymer

+ + +

+ + + +

+ + + +

+ + + +

Ethene Ethene Ethene Ethene Ethene

Propene Propene Propene Propene Propene

Chloroethene Chloroethene Chloroethene Chloroethene Chloroethene

Tetrafluoroethene Tetrafluoroethene Tetrafluoroethene Tetrafluoroethene Tetrafluoroethene

Polyethene

Polychloroethene

Polypropene

Polytetrafluoroethene

Condensation Reaction and Polymerization

• Monomer having different functional groups on both ends • Different functional groups react together • Forming a covalent bond with removal/loss of a molecule

Monocarboxylic Acid + Monoalcohol → Ester

Monocarboxylic Acid + Monoamine → Amide

Ester bond

Amide bond

Dicarboxylic Acid + Diamine → Polyamide

Dihydric Alcohol + Dicarboxylic Acid → Polyester

Condensation Reaction Polymerization Polyester

Polyester bond

Condensation Reaction Polymerization Polyamide

Polyamide bond

http://faculty.uscupstate.edu/llever/Polymer%20Resources/Synthesis.htm

http://www.pslc.ws/macrog/nylon.htm

Ethane 1, 2 diol + Benzene 1, 4 Dicarboxylic acid → Ethene terephthalate

Condensation Polymerization Polyester

Both ends same functional gps

Polyester formation • Monomer with Carboxyl (COOH) and hydroxyl (OH) functional gp join together (Ester link) • Ethane 1, 2 diol + Benzene 1, 4 Dicarboxylic acid → Terylene, PET, (Polyethene terephthalate) • Loss of water molecule (condensation) • Repeating unit

Advantages of polymers • Cheap, Light, insoluble in water - low toxicity • Strong covalent bonds –unreactive, resistant to chemicals, heat or organic solvents • High Strength and electrical insulators • Flexible, easily moulded to form other shapes, sheets, rods or tubes. • Production of fibres – garments and clothes

Both ends same functional gps Both ends different functional gps

Monomer Monomer Monomer Monomer

Polymer (Polyester)

Hexane 1,6 dioic acid + Hexane 1,6 diamine → Nylon 6.6

Condensation Polymerization Polyamide

Both ends same functional gps Both ends same functional gps Both ends different functional gps

Monomer Monomer Monomer Monomer

Polymer (Polyamide)

Polyamide formation • Monomer with Carboxyl (COOH) and Amine (NH2) functional gp join together (Amide link) • Hexane 1,6 dioic acid + Hexane 1,6 diamine → Nylon 6.6 • Loss of water molecule (condensation) • Polypeptide chains have amide link • Repeating unit

Advantages of polymers • Cheap, Light, insoluble in water - low toxicity • Strong covalent bonds –unreactive, resistant to chemicals, heat or organic solvents • High Strength and electrical insulators • Flexible, easily moulded to form other shapes, sheets, rods or tubes. • Production of fibres – garments and clothes