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

Polymer formation from monomers starts by _________.

  1. hydrolysis of monomers

  2. conversion of monomers to monomer ion by protons

  3. coordination reaction between monomers

  4. condensation reaction between monomers

  5. none of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

It is a correct answer. Polymer formation from monomers starts by condensation reaction between monomers.

Multiple choice

Plasticisers are added to synthetic plastics to _____________.

  1. impart flexibility

  2. develop new improved properties not present in the original resin

  3. improve workability during fabrication

  4. are able to permeate into the free volume around the polymer chains

  5. all of the above
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

It is the correct answer. 

Multiple choice

The semi-synthetic polymer on the basis of source is ________.

  1. Cellulose

  2. Rayon

  3. Polythene

  4. Polyacrylate

  5. Nylon 6,6
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The classification based on source is sub categorized in-

  1. Natural polymers - These polymers are found in plants and animals. Examples are proteins, cellulose, starch, resins and rubber.
  2. Semi-synthetic polymers - Cellulose derivatives as cellulose acetate (rayon) and cellulose nitrate, etc. are the usual examples of this sub category.
  3. Synthetic polymers - A variety of synthetic polymers as plastic (polythene), synthetic fibres (nylon 6,6) and synthetic rubbers (Buna - S) are examples of manmade polymers extensively used in daily life as well as in industry.
Multiple choice

Which of the following statements is incorrect? P. Cellulose is the homopolymer of fructose. Q. Caprolactum is the precursor unit of nylon 6. R. Plexiglass is the addition polymer of methyl methacrylate. S. Glyptal is the copolymer of ethylene glycol and formaldehyde.

  1. Only P and Q

  2. Only Q and R

  3. Only R and S

  4. Only P and R

  5. Only P and S
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

P. Cellulose is the homopolymer of glucose as monomer unit. Insulin is the homopolymer of fructose as monomer unit. Q. Nylon 6 is obtained by heating caprolactum with water at a high temperature. R. Plexiglass or polymethyl methacrylate is the addition polymer of methyl methacrylate. S. Glyptal is the copolymer of ethylene glycol and phthalic acid. Bakelite is the condensation polymer (copolymer) of phenol and formaldehyde. Hence, both the statements P and S are incorrect.

Multiple choice

Which of the following synthetic polymers is/are elastomer/s?

  1. Polychloroprene
  2. Baypren
  3. Neoprene
  4. UFR

  1. Only 1 and 2

  2. Only 2 and 3

  3. Only 3 and 4

  4. Only 1, 2 and 3

  5. Only 2, 3 and 4
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Synthetic polymers are human-made polymers. From the utility point of view they can be classified into four main categories: thermoplastics, thermosets, elastomers and synthetic fibers. An elastomer is a polymer with viscoelasticity (having both viscosity and elasticity) and very weak inter-molecular forces. Examples are- polychloroprene, Neoprene, Baypren, Elastolefin urea formaldehyde resin (UFR), etc.

Multiple choice

Which of the following pairs represents thermosetting polymers with respect to the classification based on molecular forces?

  1. Buna-S, Neoprene

  2. Nylon 6,6, Neoprene

  3. UFR, Bakelite

  4. Bakelite, Polythene

  5. UFR, Polythene
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Thermosetting polymers are cross linked or heavily branched molecules, which on heating undergo extensive cross linking in moulds and again become infusible. These cannot be reused. Some common examples are bakelite, urea-formaldelyde resins (UFR), etc.

Multiple choice

Which of the following is/are para-aramid synthetic fibre/s?

  1. Kevlar
  2. Nomex
  3. Twaron

  1. Only 1

  2. Only 2

  3. Only 1 and 2

  4. Only 2 and 3

  5. Only 1 and 3
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Kevlar and Twaron both are the registered trademark for a para-aramid synthetic fibre, related to other aramids such as Nomex and Technora. Kevlar is used in modern times to make modern drumheads that withstand high impact, tyre making and underwater applications, etc. Nomex is the registered trademark for meta-aramid synthetic fibre. Hence, both 1 and 3 are para-aramid synthetic fibers.