Questions Related to polymer

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

Which of the following is used in conveyor belt?

  1. PVC

  2. Polythene

  3. Neoprene

  4. none of these

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

In order to move the belt and the material to transport one or both the pulleys should be power-driven. These belts are generally made of rubber, PVC, Urethane, Neoprene, Nylon, Nitrile, Polyester, leather, polythene and others. The industrial conveyor belts are made up of multiple layers of material.


Hence, the correct options are $\text{A}, \text{B}$ and $\text{C}$

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

Which of the following is not true?

  1. Step growth polymerisation required a bifunctional monomer.

  2. Nylon $6$ is an example of step- growth polymerisation
  3. Nylon $6$ is an example of Chain growth polymerisation.
  4. Chain growth polymerisation involves homopolymerisation only.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Nylon 6 is formed by the ring-opening polymerization of caprolactam, which is a type of chain-growth polymerization, not step-growth. Therefore, the statement that it is step-growth is false.

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|CH3CH=CH2monomerofneutralrubberCH2=C|CH3−CH=CH2monomerofneutralrubber             CH2=C|ClCH=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

State True or False.

The presence of double bonds in rubber molecules influence their structure and reactivity.

  1. True

  2. False

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The given statement is true.
The presence of double bonds in rubber molecules influence their structure and reactivity.
In natural rubber, double bonds have cis configuration. Hence, the chains do not come closer this results in weak intermolecular attractions. Natural rubber has coiled structure, it is elastic and non-crystalline. 
In gutta-percha(synthetic rubber) double bonds have trans configuration. The zig-zag chains pack more closely. It is highly crystalline, non elastic, hard & brittle.

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.