Question

Which material is most commonly used for the manufacture of Polyester resin ?

• A. Paper
• B. Metal
• C. Plastic
• D. Glycols

Hint:

Logic Tip: Polyester resin is produced using alcohol compounds called Glycols along with organic acids during polymerization.

Answer 1

The Correct Option is D

Concept:
Polyester resin is one of the most widely used synthetic resins in sculpture, casting, fibre-glass work, automobile parts, and industrial applications. It is produced through a chemical reaction called polymerization, mainly involving alcohol compounds and organic acids. Among the important raw materials used in this manufacturing process are glycols.

Step 1:
Polyester resin is a synthetic polymer that becomes hard and durable after curing. It is commonly used because it is:
• Strong and lightweight
• Resistant to chemicals and moisture
• Easy to mould into different shapes
• Suitable for fibre-glass reinforcement The resin is formed through a reaction between:
• Polyhydric alcohols (mainly glycols)
• Dibasic organic acids Thus, glycols are an essential component in polyester resin manufacturing.

Step 2:
Glycols are alcohol-based chemical compounds containing hydroxyl (\(-OH\)) groups. Common examples include:
• Ethylene glycol
• Propylene glycol These compounds react chemically with acids to form long-chain polyester molecules. Because of this, glycols serve as one of the primary raw materials in polyester resin production.

Step 3:
Option (1) Paper
Paper is not used in the manufacture of polyester resin. Instead, paper may sometimes be coated or laminated using polyester resin. Option (2) Metal
Metals are not chemical ingredients for polyester resin production. Metals may be used as moulds or supporting structures only. Option (3) Plastic
Polyester resin itself becomes a type of plastic after polymerization. Plastic is therefore a final product category rather than the raw material used to manufacture the resin.

Step 4:
Since glycols are chemically involved in the formation of polyester chains during resin manufacturing, the correct answer is: \[ \boxed{\text{(4) Glycols}} \]