Introduction to Polymers

Natural Polymers in Everyday Items

https://www.youtube.com/watch?v=eqFm_7KyfHI

General Structure of Polymers

• Monomer – is a small molecule.

• Polymer – long chain-like molecule made up of a repeated pattern of monomers.

• Polymerization - is a chemical process by which monomers are joined to form polymers.

General Structure of Polymers

• Homopolymer – a polymer of a single type of monomer

– e.g. polyethylene – used to make plastic bags, plastic wrap, squeeze bottles…

General Structure of Polymers

• Copolymer – has two or more types of monomers combined to form the polymer chain

– e.g. SBS rubber – Poly(styrene-butadiene-styrene) is a hard rubber used for soles of shoes, tire treads…

Synthetic Addition Polymers

• An addition polymer is the result of the reaction between monomers with unsaturated C-C bonds.

– e.g. PTFE is also known as Teflon, the slippery surface that prevents food from sticking

Synthetic Addition Polymers

• Other addition polymers can be made from monomers containing methyl-, chloro-, cyano-and phenyl- substituents.

• In each case, the carbon-carbon double bond becomes a single bond.

• The variety of substituent groups leads to whole range of properties.

Example 1: Polyvinyl Chloride (PVC)• polymer of the

chloroethene monomer

• used in pipes, construction materials, tiles, clothing, reusable bags, etc.

Example 2: Polystyrene• polymer of styrene (phenylethylene)

monomers

• used in heat-resistant disposable drinking cups, plastic toys, food containers, packaging material, etc.

Drawing a Polymer1. Draw three structural diagrams of the

monomer. Show each with the double-bonded carbon atoms in a line.

2. Remove the double bonds, replacing them with single bonds. Connect the monomers to each other with single bonds to form a chain.

3. Add lines at each end to indicate that this is just one segment of a longer polymer.

Drawing a Polymer• Example: Draw the addition polymer formed

from cis-but-2-ene.

Drawing a Polymer• Example: Draw the addition polymer formed

from cis-but-2-ene.

Drawing a Monomer

1. Identify the repeating unit.

2. Draw the repeating unit, replacing the single bond between the two carbon atoms with a double bond.

Drawing a Monomer

• Example: Draw a structural diagram of the monomer used to make Saran.

Drawing a Monomer

• Example: Draw a structural diagram of the monomer used to make Saran.

1,1-dichloroethene