Polymers Of Commercial Importance

To solve this matching question, we need to understand the properties and common applications of each type of polymer mentioned. Let's match List-I with List-II using our knowledge of these substances:

1. Phenol-formaldehyde resin: This is a polymer known as Novolac. It is used in the production of Bakelite, a widely used thermosetting plastic.
   • Matches with: II (Novolac)
2. The copolymer of 1,3-butadiene and styrene: This polymer is commonly called Buna-S. It is a type of synthetic rubber used in tires.
   • Matches with: III (Buna-S)
3. Polyester of glycol and phthalic acid: This polymer is known as Glyptal, used in paints and as an electrical insulating material.
   • Matches with: I (Glyptal)
4. Polyester of glycol and terephthalic acid: This polymer is known as Dacron or Poly(ethylene terephthalate) (PET). It is used in fibers for clothing and containers for liquids and foods.
   • Matches with: IV (Dacron)

Based on the matches above, the correct option is: A-II, B-III, C-I, D-IV.