P O L Y M E R S The Academic Support Center @ Daytona State College (Science 106, Page 1 of 25
POLYMERS Polymers are large, long-chain molecules. found in nature, including cellulose in plants, starches in food, proteins, and DNA in the body. also synthetic such as polyethylene and polystyrene, Teflon, and nylon. have small repeating units called monomers. can be made from reaction of small alkenes. 2 The Academic Support Center @ Daytona State College (Science 106, Page 2 of 25
STARCH The Academic Support Center @ Daytona State College (Science 106, Page 3 of 25
CELLULOSE The Academic Support Center @ Daytona State College (Science 106, Page 4 of 25
PROTEINS The Academic Support Center @ Daytona State College (Science 106, Page 5 of 25
DNA & RNA The Academic Support Center @ Daytona State College (Science 106, Page 6 of 25
COMMON SYNTHETIC POLYMERS 7 The Academic Support Center @ Daytona State College (Science 106, Page 7 of 25
COMMON SYNTHETIC POLYMERS 8 The Academic Support Center @ Daytona State College (Science 106, Page 8 of 25
COMMON SYNTHETIC POLYMERS The Academic Support Center @ Daytona State College (Science 106, Page 9 of 25
POLYMERIZATION In polymerization, small repeating units called monomers join to form a long chain polymer. H H C C H H H H + C C + C C H H H H H H monomer unit repeats Ethylene monomers chain continues H H H H H H C C C C C C H H H H H H n Polyethylene chain continues The Academic Support Center @ Daytona State College (Science 106, Page 10 of 25
POLYMERS FROM ADDITION REACTIONS 11 The Academic Support Center @ Daytona State College (Science 106, Page 11 of 25
MORE MONOMERS AND POLYMERS 12 The Academic Support Center @ Daytona State College (Science 106, Page 12 of 25
LEARNING CHECK What is the starting monomer for polyethylene? Ethene (ethylene) CH 2 =CH 2 The Academic Support Center @ Daytona State College (Science 106, Page 13 of 25
LEARNING CHECK Name the monomer used to make Teflon and write a portion of a Teflon polymer using four monomers. F F F C=C F tetrafluoroethene F F F F F F F F C C C C C C C C F F F F F F F F portion of Teflon The Academic Support Center @ Daytona State College (Science 106, Page 14 of 25
RECYCLING PLASTICS Recycling is simplified by using codes on plastic items. 1 PETE Polyethyleneterephtalate 2 HDPE High-density polyethylene 3 PVC or PV Polyvinyl chloride 4 LDPE Low-density polyethylene 5 PP Polypropylene 6 PS Polystyrene The Academic Support Center @ Daytona State College (Science 106, Page 15 of 25
RECYCLING PLASTICS The Academic Support Center @ Daytona State College (Science 106, Page 16 of 25
LEARNING CHECK What types of plastic are indicated by the following codes? A. 3 PV B. C. 5 PP 6 PS The Academic Support Center @ Daytona State College (Science 106, Page 17 of 25
SOLUTION What types of plastic are indicated by the following codes? 3 A. PV Polyvinyl chloride B. 5 Polypropylene C. PP Polystyrene. 6 PS The Academic Support Center @ Daytona State College (Science 106, Page 18 of 25
POLYMERIZATION An alkene (monomer) can add to another molecule like itself to form a chain (polymer). Three methods: Cationic, a carbocation intermediate Free radical Anionic, a carbanion intermediate (rare) The Academic Support Center @ Daytona State College (Science 106, Page 19 of 25
CATIONIC POLYMERIZATION The Academic Support Center @ Daytona State College (Science 106, Page 20 of 25
TERMINATION STEP OF CATIONIC POLYMERIZATION The chain growth ends when a proton is abstracted by the weak base of the acid used to initiate the reaction. The loss of a hydrogen forms an alkene and ends the chain growth so this is a termination step. The Academic Support Center @ Daytona State College (Science 106, Page 21 of 25
CATIONIC POLYMERIZATION USING BF 3 AS CATALYST The Academic Support Center @ Daytona State College (Science 106, Page 22 of 25
RADICAL POLYMERIZATION In the presence of an initiator such as peroxide, free-radical polymerization occurs. The Academic Support Center @ Daytona State College (Science 106, Page 23 of 25
ANIONIC POLYMERIZATION For an alkene to gain electrons, strong electronwithdrawing groups such as nitro, cyano, or carbonyl must be attached to the carbons in the double bond. The Academic Support Center @ Daytona State College (Science 106, Page 24 of 25
Questions Compiled from various sources by D. Leonard (Learning Specialist) The Academic Support Center @ Daytona State College http://www.daytonastate.edu/asc/ascsciencehandouts.html The Academic Support Center @ Daytona State College (Science 106, Page 25 of 25