Answer: Very low surface energy due to strong C-F bonds.
- A Very low surface energy due to strong C-F bonds
- B Its unusually high melting point near 327°C
- C Its relatively high density compared to other plastics
- D An extensively cross-linked three-dimensional network
Correct answer: A. Very low surface energy due to strong C-F bonds
Explanation: The extremely strong C-F bonds in PTFE give it the lowest coefficient of friction, making surfaces non-stick.
Addition polymerisation simply links monomers containing a double bond with nothing left over, while condensation polymerisation joins two different monomers through a reaction (often forming an ester or amide bond) that releases a small molecule like water at each step.
Concept context
Large molecules made of repeating monomer units. Covers addition and condensation polymerisation, natural and synthetic polymers (nylon, PVC, Bakelite, natural rubber), and their real-world industrial applications.