Chemistry

Polymers and Plastics

1,228 Questions

Polymers and plastics questions explore the properties, synthesis, and applications of various synthetic and natural polymers. Key topics include biodegradable plastics, vulcanization, and polymer nanocomposites. These concepts are frequently tested in science and engineering competitive exams.

Biodegradable plasticsPolymer nanocompositesVulcanization of rubberPolymer molecular weightAsphalt binders

Polymers and Plastics Questions

Multiple choice

Which of the following is not a property of nylon?

  1. Nylon is a thermoplastic polymer.

  2. Nylon fibers are fairly strong and elastic.

  3. Nylon fibers are lightweight and lustrous.

  4. It is cheaper than natural silk and can be woven like silk fiber.

  5. Nylon fibers absorb very little water.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the correct option as this is not a property of nylon. It is rayon that is cheaper than natural silk and can be woven like silk fiber.

Multiple choice

Polyester is a synthetic fiber in which the polymer units are linked by ester groups. Which of the following is not a property of polyester?

  1. Polyester fibers are weaker in strength than nylon fibers.

  2. Polyester fiber is not attacked by moths and ordinary chemicals.

  3. Polyester is a thermoplastic polymer.

  4. Polyester fibers are softer than nylon fibers.

  5. Polyester fiber is strong, wrinkle resistant and easy to wash
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the correct option as this is not a property of polyester. Polyester fibers are stronger than nylon fibers.

Multiple choice

Which of the following statements is/are false?

a. PET is naturally colourless with high transparency. b. Terrycot is a mixture of acrylic and cotton, and terrywool is a mixture of acrylic and wool. c. Nylon is made up of repeating units of a chemical called amide.

  1. Only a

  2. Both a and b

  3. Only b

  4. Both b and c

  5. Only c
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is a wrong option as this statement is true. Terrycot is a mixture of polyester and cotton, and terrywool is a mixture of polyester and wool.

Multiple choice

A plastic that can be softened repeatedly by heating and can be moulded into different shapes again and again is called a thermoplastic. Which of the following plasctics are thermoplastics?

a. Polythene b. Bakelite c. PVC d. Melamine

  1. Both a and b

  2. Both a and c

  3. Both a and d

  4. Both b and c

  5. Both b and d
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is the correct option. Polythene and PVC are thermoplastics as they can be softened repeatedly by heating and can be moulded into different shapes again and again.

Multiple choice

Consider the following statements:

  1. PVC (Poly Vinyl Chloride) is commonly used as the insulation on electrical cables.
  2. Most plastics are made from petroleum (oil or natural gas).

Which of the above statements is/are true?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
  1. Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is commonly used as the insulation on electrical cables; PVC used for this purpose needs to be plasticized.
    1. Most plastics are made from petroleum (oil or natural gas). First, refineries process the crude oil to produce fuels, such as gasoline, and many petrochemicals. Petrochemicals then are used by chemical plants to obtain many products, like fertilizers, lubricants, and plastic resins. Plastic resins are, in turn, used to produce many different types of plastics.
Multiple choice

Polythene is polymer of:

  1. Ethylene

  2. Propylene

  3. Acetylene

  4. Aniline
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Polythene (polyethylene) is a polymer formed by the polymerization of ethylene (ethene) molecules. Multiple ethylene monomers (C2H4) join together to form long chains of -(CH2-CH2)- repeating units. Propylene makes polypropylene, acetylene polymerizes differently, and aniline produces polyaniline - none produce polythene.

Multiple choice

Which is widely used in the plastic industry for manufacturing bakelite?

  1. Ethyl alcohol

  2. Phenol

  3. Orth-cresol

  4. Catechol
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bakelite is a phenol-formaldehyde resin, the first synthetic plastic made from industrial components. Phenol reacts with formaldehyde under heat and pressure to form this thermosetting polymer. Ethyl alcohol is used as a solvent, cresols are phenol derivatives, and catechol is an isomer - none are the primary reactant.