Introduction to Polymers

Overview

• What are polymers?

• How are polymers named?

• What is a polymer crosslinker?

Polymers are all around us!

Contact lenses

Sport equipment Clothingpolyester

Plasticcontainers

Synthetic(man-made)

Natural

DNAWood

Carbohydrates(sugars)

Protein(amino acids)

Rubber

Toys

Polymer Definition

polymer

“many” “part”

Polymers are large molecules made of repeating parts

The repeating parts are chemical compounds

Polymers are made of chains of repeating compounds

Large(macro)

small(micro)

Polyester fibersPolyester coat

Polymers are made of chains of repeating compounds

Large(macro)

small(micro)

Polyester fibersPolyester coat

Strings of ‘ester’compounds

ester ester ester ester

Joined bycovalent bonds

Large(macro)

small(micro)

Polyester fibersPolyester coat

ester ester ester ester

Esters are compoundsmade of elements like

C, H, O

Covalent bonds form when these atoms

share electrons

Polymers are made of chains of repeating compounds

Naming polymers

ester ester ester ester Polyester

A A A A A A A PolyA

mer mer mer mer mer Polymer

sugar sugar sugar sugar

Name this polymer:

Naming polymers

ester ester ester ester Polyester

A A A A A A A PolyA

mer mer mer mer mer Polymer

sugar sugar sugar sugar

Name this polymer:Polysugar

(a carbohydrate!)

Crosslinkers stabilize polymer chains

ester ester ester ester

Polyester fibersPolymer molecule chains

A crosslinker is acompound that bonds polymer chains together

Beads on a string

One fiber

Crosslinkers stabilize polymer chains

ester ester ester ester

Polyester fibersPolymer molecule chains

Beads on a string

A crosslinker is acompound that bonds polymer chains together

One fiber

What are some properties of polymers?

How can we change the properties of polymers?

vs.

The chemical properties of repeat units and their crosslinkers determine the physical properties of polymers

• Density• Melting temperature

• Transparency• Stiffness

See-throughFlexible

Can’t see throughFlexible

Can’t see throughRigid, stiff

Remember the TP lab?How does TP absorb water?

cellulose cellulose cellulose

+ Water

Toilet paper contains a polymer called cellulose

Remember, paper comes from wood, a

natural polymer!

Example

Remember the TP lab?How does TP absorb water?

cellulose cellulose cellulose

cellulose cellulose cellulose

+ Water

Toilet paper contains a polymer called cellulose

Water loves cellulose!

This makes TP absorbant!

Example

Remember the TP lab?How does TP absorb water?

So, the chemical properties of a

polymer (cellulose) in paper help determine its physical properties

(absorbancy)

Example

Polyethylene (PE)

ethylene ethylene ethylene

An important synthetic polymer

Example

C CH H

H H

This is what the compound calledethylene looks like:

This repeating compound is called ethylene-Its chemical formula is C2H4

Polyethylene (PE)

ethylene ethylene ethylene

An important synthetic polymer

Example

C CH H

H HC CH H

H HC CH H

H HC CH H

H H

This is what the compound calledethylene looks like:

This repeating compound is called ethylene-Its chemical formula is C2H4

Polyethylene (PE)

ethylene ethylene ethylene

An important synthetic polymer

Example

Deoxyribonucleic acid(DNA)

An importantnatural polymer

Wow, that is complex!

Example

Deoxyribonucleic acid(DNA)

An importantnatural polymer

Wow, that is complex!

DNA double helix

Cartoon ofDNA

Example

polymer

Polymers are used in medical devices

hip

knee

Shin bone

Thigh bone

Thigh bone

cartilage

pelvis

Polymer Synthesis Lab!

Homemade silly putty

C CH H

H OH

Repeat unit = vinyl alcohol

Crosslinker = borate ionsBOH

OHOHHO

Homemade silly putty

C CH H

H O

B

C CH H

O HC CH H

H OC CH H

O H

B

C CH O

H HC CO H

H HC CH O

H HC CO H

H H