The Evolution of Plastics

Historical Background

• Billiard Ball Origins
  • Originally made from elephant tusks (ivory)
  • Excessive hunting in the 19th century led to a decline in elephant populations
  • Billiard ball makers sought alternatives
  • John Wesley Hyatt invented celluloid in 1863 as a substitute

Development of Celluloid

• Made from cellulose (found in wood and straw)
• Issues: not heavy enough, didn’t bounce correctly
• Advantages: could mimic expensive materials (coral, tortoiseshell, amber)
• First official plastic but highly flammable

Evolution of Synthetic Plastics

• Bakelite (1907)
  • Invented by combining phenol and formaldehyde
  • Less flammable, raw materials readily available
• 1920s Developments
  • Polystyrene: spongy plastic used in insulation
  • Polyvinyl chloride (PVC): flexible, hardy
  • Acrylics: transparent, shatter-proof (mimic glass)
• 1930s Developments
  • Nylon: mimics silk, many times stronger
  • Polyethylene: versatile, used in grocery bags, shampoo bottles, bulletproof vests

Manufacturing Advancements

• Injection Molding
  • Technique to insert melted plastics into molds, rapid hardening
  • Enabled mass production of varied and complex shapes

World War II Era

• Plastics used extensively during WWII
  • Plastic helmet liners, vinyl raincoats
  • Plexiglass cockpits, nylon parachutes
• Post-war shift to consumer products
  • Replaced materials like wood, glass, fabric
  • Expanded packaging options

The Plastics Century

• Rise in plastic consumer goods
  • Plastic garbage bags, stretchy wrap, squeezable bottles
  • Takeaway containers, food storage
• Convenience vs. Environmental Impact
  • Plastics largely made from nonrenewable resources
  • Designed for single-use, long decomposition periods

Future Innovations

• Focus areas:
  • Reducing plastic use
  • Developing biodegradable plastics
  • Innovative recycling methods