Polymers JEE Main previous year questions with solutions

5 solved JEE Main questions on Polymers, free to read — no sign-in needed. The full chapter has 93 questions; sign in to attempt the remaining 88 in the exam simulator.

Answers checked against the official answer keys.

1. Q1JEE Main 2023 (11 Apr, Shift 2)
   Given below are two statements: Statement I: Ethane at $333$ to $343K$ and $6-7$ atm pressure in the presence of ${AlEt}_{3}$ and ${TiCl}_{4}$ undergoes addition polymerization to give LDP. Statement II: Caprolactam at $533-543K$ in ${H}_{2}O$ through step growth polymerizes to give $Nylon6$. In the light of the above statements, choose the correct answer from the options given below:
   1. A.Statement I is false but Statement II is true
   2. B.Statement I is true but Statement II is false
   3. C.Both Statement I and Statement II are true
   4. D.Both Statement I and Statement II are false
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   Answer: (A)

   Low Density Polyethylene is obtained by the polymerisation of ethene under high pressure of $1000-2000atm$ at $350-570K$ in the presence of an initiator. High Density Polyethylene is obtained when polymerisation is done in the presence of Ziegler-Natta catalyst at $333-343K$ under $6-7atm$ pressure. Nylon-6 is manufactured from the monomer called caprolactam. The monomer caprolactam is heated at $533-543K$in an inert atmosphere, it polymerises to give nylon-6.
2. Q2JEE Main 2023 (11 Apr, Shift 1)
   The polymer X-consists of linear molecules and is closely packed. It is prepared in the presence of trimethylammoniumpropyl and titanium tetrachloride under low pressure. The polymer X is
   1. A.High density polythene
   2. B.Polyacrylonitrile
   3. C.Low density polythene
   4. D.Polytetrafluoroethane
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   Answer: (A)

   High-density polyethylene (HDPE) is commonly prepared in the presence of a Ziegler-Natta catalyst. The information provided describes the preparation and characteristics of a high-density polyethylene (HDPE) polymer. HDPE is a widely used thermoplastic polymer known for its high strength, durability, and excellent chemical resistance. The presence of trimethylammoniumpropyl (TMP) and titanium tetrachloride (${TiCl}_{4}$) indicates that the polymerization process is likely carried out using a Ziegler-Natta catalyst system. This catalyst system enables the production of high-density polyethylene by controlling the polymerization conditions.
3. Q3JEE Main 2023 (13 Apr, Shift 2)Van Der Waals Forces, Hydrogen Bonding and Metallic Bonding
   Match Lis-I with List-II. List-1 List-II A. Weak intermolecular forces of attraction I. Hexamethylenediamine + adipic acid B. Hydrogen bonding II. ${AlEt}_{3}+{TiCl}_{4}$ C. Heavily branched polymer III. $2-chloro-1,3-butadiene$ D. High density polymer IV. $Phenol+formaldehyde$ Choose the correct answer from the options given below
   1. A.A-IV, B-II, C-III, D-I
   2. B.A-IV, B-I, C-III, D-II
   3. C.A-II, B-IV, C-I, D-III
   4. D.A-III, B-I, C-IV, D-II
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   Answer: (D)

   (A) Weak Intermolecular Forces are present in polymer of $2-$chloro, $1,3-$butadiene.It is a monomer of neoprene which is a rubber(elastomer.). (B). Hydrogen Bonding is present in NYLON$-6,6$ which is a polymer of Hexamethylenediamine and adipic acid. This hydrogen bonding is due to the presence of amide group. (C) Heavily branched polymer is Bakelite which is polymer of phenol and formaldehyde. It is a crosslinked polymer. (D) High density polymer(polyethylene) preparation requires $Al(Et{)}_{3}$ and ${TiCl}_{4}$ as a catalyst (Ziegler Natta Catalyst)
4. Q4JEE Main 2022 (29 Jul, Shift 2)
   Which of the following is NOT a natural polymer?
   1. A.Protein
   2. B.Starch
   3. C.Rubber
   4. D.Rayon
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   Answer: (D)

   Natural polymers These polymers are found in plants and animals. Examples are proteins, cellulose, starch, some resins and rubber. Semi synthetic polymers are those polymers that are prepared by chemically treating natural polymers. Rayon is a regenerated cellulosic fibre. So, Rayon is semisynthetic polymer.
5. Q5JEE Main 2022 (29 Jun, Shift 1)
   The polymer, which can be stretched and retains its original status on releasing the force is
   1. A.Nylon- $6,6$
   2. B.Buna-$N$
   3. C.Terylene
   4. D.Bakelite
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   Answer: (B)

   Synthetic rubber is any vulcanisable rubber like polymer, which is capable of getting stretched to twice its length. However, it returns to its original shape and size as soon as the external stretching force is released. Thus, synthetic rubbers are either homopolymers of $1,3$ - butadiene derivatives or copolymers of $1,3$ - butadiene or its derivatives with another unsaturated monomer. Buna-N is an example of synthetic rubber.