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Polymers. Polymers. polymer - a long chain composed of a repeating sequence of molecules monomer - the “pieces” that link together to form a polymer natural polymers - e.g. protein, starch, cellulose, DNA synthetic polymers - e.g. nylon, silicone. Polymerization.
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Polymers • polymer - a long chain composed of a repeating sequence of molecules • monomer - the “pieces” that link together to form a polymer natural polymers - e.g. protein, starch, cellulose, DNA synthetic polymers - e.g. nylon, silicone
Polymerization • the process of linking C atoms to form long chains of repeating units • the longer the chain of C atoms, the higher the higher the boiling pt • to design alkanes with desired mp/bp, possible to control chain length e.g. C2H6 gas C8H18 liquid C25H52 solid
Polymerization two types 1) addition polymerization 2) condensation polymerization
Addition Polymerization • involves bonding of monomers without elimination of atoms • bonding occurs by saturating (opening up) the double bonds e.g. H H H H H H H H C = C + C = C —> H - C - C - C = C H H H H H H H H ethylene monomers polyethylene
Addition Polymerization • keep adding CH2 units H H H H H - C - C - C = C H H H H • n can be very large • Teflon, Saran, Lucite, and Plexiglass are all the result of addition reactions
Condensation Polymerization • polymer formation involves the production of water • starting materials are bifunctional (two functional groups) e.g dacron (polyester) H H O O HO - C - C - OH C - - C H H HO OH ethylene glycol terephthalic acid