Crash Course Chemistry: Polymers

Introduction to Billiards and Ivory

• Charles Darwin owned ivory billiard balls, a luxury afforded by few due to cost and rarity.
• Billiard industry faced issues due to rising costs and rarity of ivory from elephants.
• Phelan and Collander Pool Supply Company offered a reward for a substitute for ivory.

The Invention of Synthetic Polymers

• John Wesley Hyatt created billiard balls from nitrocellulose as an ivory substitute, although dangerous due to flammability.
• Hyatt's work laid the groundwork for the polymer industry.

Introduction to Polymers

• Polymers are large chains or networks of repeating units called monomers.
• They can be tailored with properties like stretchiness, strength, transparency, and recyclability.

Polyethylene

• Created from ethene (ethylene) monomers via addition polymerization.
• Transparent and thermoplastic, allowing for recyclability.
• HDPE vs. LDPE: difference in strength and processing due to chain length.

Other Common Polymers

• PVC (Polyvinyl Chloride): Derived from chloroethene.
• Polypropylene: Derived from propene.
• Polystyrene/Styrofoam: Derived from styrene.
• PTFE/Teflon: Derived from tetrafluoroethylene, known for low friction due to fluorine's electronegativity.

Polymerization Processes

• Addition Polymerization: Monomers join without byproducts, initiated by free radicals.
• Condensation Polymerization: Monomers join with byproducts like water, important for polymers like nylon.

Natural Polymers

• Amino acids form proteins through condensation reactions guided by DNA.
• Other natural polymers include polysaccharides, DNA, and RNA.

Conclusion

• Polymers have diverse applications and are crucial in both synthetic materials and biological processes.

Credits for the Episode

• Written by Hank Green
• Chemistry consultant: Dr. Heiko Langner
• Filmed, edited, and directed by Nicholas Jenkins
• Additional Credits: Editing, script supervision, sound design, graphics.