Chemistry

Polymers and Plastics

1,227 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 classification of polymers introduction to polymers and its classification polymer polymers chemistry

Zeifler-Natta catalystic system is a combination of :

  1. $Rh(Ph _{3}P) _{3}CI$ and $H _{2}$
  2. $Ti(O^{i}Pr) _{4}$ and $^{t}BuOOH$
  3. $Rh(Ph _{3}P) _{3}CI$ and $CO$
  4. $TiCI _{4}$ and $AI(C _{2}H _{2}) _{3}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Ziegler-Natta catalysts are organometallic compounds used for polymerization of olefins. The classical Ziegler-Natta catalyst combines TiCl4 (titanium tetrachloride) with Al(C2H5)3 (triethylaluminum, often written as AlEt3). Option D correctly shows this combination, though the formula notation has typographical issues with subscript formatting. B and C show different catalyst systems (Wilkinson's catalyst with CO/H2, and titanium isopropoxide with tert-butyl hydroperoxide for epoxidation).

Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

Monomers of Natural Rubber and Neoprene are Respectively : 

  1. $CH _3 - \underset{CH _3}{\underset{|}{C}} = CH - CH _3 , \, \, CH _3 - \underset{Cl}{\underset{|}{C}} = CH - CH _3$
  2. $CH _2 = \underset{CH _3}{\underset{|}{C}} - CH = CH _2$ $CH _2 = \underset{Cl}{\underset{|}{C}} - CH = CH _2$
  3. $CH _2 = CH - CH = CH _2$ , $CH _2 = CH - Cl$
  4. $CH _2 = \underset{Cl}{\underset{|}{C}} - CH = CH _2$ $CH _2 = \underset{CH _3}{\underset{|}{C}} - CH = CH _2$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

CH2=C|CH3−CH=CH2monomerofneutralrubberCH2=C|CH3−CH=CH2monomerofneutralrubber             CH2=C|Cl−CH=CH2monomerofneoprene

Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

Polymerisation may occur through intermediate formation of___________.

  1. carbocations

  2. carbanions

  3. free radicals

  4. carbenes
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation

Polymerization is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many forms of polymerization like free radical electrophilic and nucleophile polymerisations through the formation of free radicals, carbanions and carbocation intermediates. Carbene doesn't form in the reaction mechanism as intermediate.
Hence, options A, B and C are correct.

Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

The basis on the mode of their formation, the polymers can be classified:

  1. As addition polymers only

  2. As condensation polymers only

  3. As copolymers

  4. Both as addition and condensation polymers
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

On the basis of the mode of their formation, the polymers can be classified as addition polymers and condensation polymers.
Addition polymers are formed by chain growth polymerization and condensation polymers are formed by the combination of two monomers by the elimination of a small molecule like water or methyl alcohol.


Option D is correct.

Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

Polyethene is produced by :

  1. isomerization

  2. polymerisation

  3. hydrogenation

  4. all of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Polymerization is the process of reacting monomer molecules together in a chemical reaction to form polymer chains or three dimensional networks.There are many forms of polymerization like step growth and chain growth.It occurs via variety of reaction mechanisms due to functional groups present and their steric effects.

Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

Which one of the following polymers is not properly matched to its monomer?

  1. orion - acrylonirtile

  2. synthetic rubber- 2 -chlorobuta - 1, 3 - diene

  3. nylon - adipic acid & hexamethylene diamine

  4. teflon - vinyl chloride
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The Monomer of Teflon is tetrafluoroethylene, where vinyl chloride is the monomer of PVC.


So, the correct option is $D$

Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

Monomer of polythene is :

  1. propene

  2. isoprene

  3. chloroprene

  4. ethene
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Polyethylene is the most common plastic. The monomer is ethylene, a gaseous hydrocarbon with the formula ${ C } _{ 2 }{ H } _{ 4 }$ which can be viewed as a pair of methylene groups connected to each other. As it is highly reactive, the ethylene must be of high purity.

Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

Which one of the following is a phenolic resin similar to Bakelite?

  1. Catalin

  2. Melamine

  3. Celluloid

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

Catalin is a brand name for a thermosetting polymer that was popular from the 1930s. It is another phenolic resin, similar to Bakelite, but with different mineral fillers that allowed the production of light colors. Like Bakelite, it gives off a distinctive phenolic odour when heated.

Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

Identify the heteropolymer from the list given below.

  1. Polythene

  2. Nylon-6

  3. Teflon

  4. Nylon-6, 6
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
A hetero-polymer derived from two or more different (but often similar) types of monomer. Nylon 66 is made of two monomers each containing 6 carbon atoms, hexamethylenediamine and adipic acid, which give nylon 66 its name
Polythene, nylon-6 and teflon are homo polymers.
Multiple choice classification of polymers introduction to polymers and its classification polymer polymers chemistry

Which of the following is thermally stable?

  1. Silicone polymers

  2. Rayon

  3. Bakelite

  4. Perlon - L
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Silicones are polymers that include silicon together with carbon, hydrogen and oxygen.They have an alternating $  -Si-O-Si-  $ type structure. Silicones are water repellent, very resistant to chemical attack and are thermally stable since they do not decompose at high temperature.