Lab K: Introduction to Polymers

What are polymers?

Very large molecules that form when several monomer units join together to form long chains.

What are some examples of natural polymers?

What are some artificial polymers?

• Polyethylene: most common plastic used for packaging.

• Nylon: man-made synthetic fiber - first produced in 1935 by Walllace Carother’s.

• Polystyrene: synthetic aromatic polymer used in food service packaging industry.

• Polyvinyl chloride (PVC)

Draw the structures of examples of polymers

What are 2 methods of polymerization?

1. ADDITION (chain growth) polymerization: ex. polystyrene, PVC

   • Involves addition of monomer units w/o loss of smaller molecules.

   • Monomers must contain double or triple bonds.

2. CONDENSATION (step growth) polymerization: ex. Nylon-6,6, Nylon-6,10

   • Involves reaction b/w 2 monomer units w/ reactive end functional groups w/ loss of small molecules e.g. water, methanol, HCl

What is the monomer used in synthesis of polystyrene?

Styrene

What is the initiator and polymerization solvent?

What is the mechanism of polymerization (ADDITION polymerization)?

What are the properties and applications of polystyrene?

Properties:

• Non-polar

• Naturally transparent

• Lightweight

• Great electrical insulator

Applications:

• Disposable cups

• Food packaging

• Optical lenses

Draw the reaction scheme of a condensation reaction

Draw the reaction scheme for synthesis of Nylon-6,6

What are the monomers used for synthesis of Nylon-6,6?

• Adipoyl chloride

• Hexamethylenediamine

What are the physical properties and applications of Nylon-6,6?

Physical properties:

• Strength, durability, high thermal stability

Applications:

• Sports equipment

• Industrial fabrics: tire cords, conveyor belts, seat belts

• Apparel: swimsuits, jackets

• Carpets, rugs

• Automotive industry

Draw the reaction scheme for synthesis of Nylon-6,10

What are the physical properties and applications of Nylon-6,10?

Physical properties:

• Good chemical resistance, low

• Moisture absorption

Applications:

• Electrical insulation

• Medical tubing

• Recreational sports equipment

Safety hazards?

Adiopyl chloride/hexane is a flammable liquid.

Hexamethylenediamine/sodium hydroxide is corrosive.