Molecular Structure

Molecular Structure

1. Forces between molecules

   • Longer molecules have stronger forces of attraction between them. This tends to lead to longer chain plastics being
     • High melting points
     • Stiffer
     • Harder
     • Stronger

2. Modifying Plastics

   • By increasing the chain length
     • Makes it stronger
   • Packing more closely
     • Make it stronger and more dense
     • A crystalline polymer
   • Crosslinking
     • Makes it harder
   • Plasticizing
     • Make it softer and more flexible

3. Structures of Plastics

   • Some plastics have strong intermolecular forces between each molecule, these have high melting points and can be stretched easily
   • Some plastics have weak forces between each molecule, these have low melting points and are rigid