Introduction to Polymers - Cornell University

Introduction to Polymers Overview What are polymers? How are polymers named? What is a polymer crosslinker? Polymers are all around us! Natural Synthetic (man-made) Plastic containers Toys

DNA Wood Rubber Contact lenses Sport equipment Clothing polyester Carbohydrates (sugars) Protein (amino acids)

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 Polyester coat Large (macro)

Polyester fibers small (micro) Polymers are made of chains of repeating compounds Polyester coat Polyester fibers ester Large (macro) ester Strings of

estercompounds small (micro) ester ester Joined by covalent bonds Polymers are made of chains of repeating compounds Polyester coat Polyester fibers ester

Large (macro) ester small (micro) ester ester Esters are compounds Covalent bonds form made of elements like when these atoms C, H, O share electrons

Naming polymers mer mer ester A mer ester A A mer

ester A A A sugar sugar sugar Polymer Polyester ester

Name this polymer: sugar mer A PolyA Naming polymers mer mer ester A mer

ester A A mer ester A mer Polyester ester A

A Polymer A PolyA Name this polymer: sugar sugar sugar sugar

Polysugar (a carbohydrate!) Crosslinkers stabilize polymer chains Polyester fibers Polymer molecule chains ester ester ester Beads on a string One fiber A crosslinker is a compound that

bonds polymer chains together ester Crosslinkers stabilize polymer chains Polyester fibers Polymer molecule chains ester ester ester Beads on a string One fiber

A crosslinker is a compound that bonds polymer chains together ester What are some properties of polymers? vs. How can we change the properties of polymers? The chemical properties of repeat units and their crosslinkers determine the physical properties of polymers Density Melting temperature

See-through Flexible Transparency Stiffness Cant see through Flexible Cant see through Rigid, stiff Example Remember the TP lab? How does TP absorb water?

Toilet paper contains a polymer called cellulose cellulose cellulose + Water Remember, paper comes from wood, a natural polymer! cellulose Example Remember the TP lab? How does TP absorb water?

Toilet paper contains a polymer called cellulose cellulose cellulose cellulose + Water Water loves cellulose! This makes TP absorbant! cellulose cellulose cellulose

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 An important synthetic polymer Polyethylene (PE) ethylene ethylene

ethylene Example An important synthetic polymer Polyethylene (PE) ethylene ethylene ethylene This is what the compound called ethylene looks like: H H C C H H

This repeating compound is called ethylene -Its chemical formula is C2H4 Example An important synthetic polymer Polyethylene (PE) ethylene ethylene ethylene This is what the compound called ethylene looks like: H H H H H H H H C C C C C C C C

H H H H H H H H This repeating compound is called ethylene -Its chemical formula is C2H4 Example An important natural polymer Deoxyribonucleic acid (DNA) Wow, that is complex! Example An important natural polymer Deoxyribonucleic acid (DNA) Wow, that is complex! Cartoon of

DNA DNA double helix Polymers are used in medical devices pelvis Thigh bone cartilage hip knee Shin bone polymer

Thigh bone Polymer Synthesis Lab! Homemade silly putty H H C C H OH OH HO B OH OH Repeat unit = vinyl alcohol Crosslinker = borate ions Homemade silly putty

H H C C H O H H C C O H H H C C H O B H O C C H H H H

C C O H B O H C C H H H O C C H H O H C C H H