Chapter-15 Polymers

Which of the following polymers soften on heating and harden on cooling?
What are the polymers with this property collectively called? What are the
structural similarities between such polymers? Bakelite, urea-formaldehyde
resin, polythene, polyvinyls, polystyrene.

Low density polythene and high density polythene, both are polymers of ethene
but there is marked difference in their properties. Explain.

Low density polythene and high density polythene, both are pol

Phenol and formaldehyde undergo condensation to give a polymar (A) which
on heating with formaldehyde gives a thermosetting polymer (B). Name the
polymers. Write the reactions involved in the formation of (A). What is the
structural difference between two polymers?

Differentiate between rubbers and plastics on the basis of intermolecular forces.

Synthetic polymers do not degrade in the environment for a long time. How
can biodegradable synthetic polymers be made. Differentiate between
biopolymers and biodegradable polymers and give examples of each type.

Match materials given in Column I with the polymers given in Column II.
Column I Column II
(i) Natural rubber latex (a) Nylon
(ii) Wood laminates (b) Neoprene
(iii) Ropes and fibres (c) Dacron
(iv) Polyester fabric (d) Melamine formaldehyde resins
(v) Synthetic rubber (e) Urea-formaldehyde resins
(vi) Unbreakable crockery (f) cis-polyisoprene

Match the polymers given in Column I with the type of linkage present in
them given in Column II.
Column I Column II
(i) Terylene (a) Glycosidic linkage
(ii) Nylon (b) Ester linkage
(iii) Cellulose (c) Phosphodiester linkage
(iv) Protein (d) Amide linkage
(v) RNA

Match the polymers given in Column I with the preferred mode of
polymerisation followed by their monomers.
Column I Column II
(i) Nylon-6,6 (a) Free radical polymerisation
(ii) PVC (b) Ziegler-Natta polymerisation or
coordination polymerisation
(iii) HDP (c) Anionic polymerisation
(d) Condensation polymerisation

Match the polymers given in Column I with their main applications given in
Column II.
Column I Column II
(i) Bakelite (a) Unbreakable crockery
(ii) Low density polythene (b) Non-stick cookwares
(iii) Melamine-formaldehyde resin (c) Packaging material for shock
absorbance
(iv) Nylon 6 (d) Electrical switches
(v) Polytetrafluoroethane (e) Squeeze bottles
(vi) Polystyrene (f) Tyre, cords

Match the polymers given in Column I with their commercial names given in
Column II.
Column I Column II
(i) Polyester of glycol and phthalic acid (a) Novolac
(ii) Copolymer of 1, 3-butadiene
and styrene (b) Glyptal
(iii) Phenol and formaldehyde resin (c) Buna-S
(iv) Polyester of glycol and terephthalic acid (d) Buna-N
(v) Copolymer of 1, 3-butadiene
and acrylonitrile (e) Dacron

Match the polymers given in Column I with their chemical names given in
Column II.
Column I Column II
(i) Nylon 6 (a) Polyvinyl chloride
(ii) PVC (b) Polyacrylonitrile
(iii) Acrilan (c) Polycaprolactum
(iv) Natural rubber (d) Low density polythene
(v) LDP (e) cis-polyisoprene

Match the polymer of column I with correct monomer of column II.
Column I Column II
(i) High density polythene (a) Isoprene
(ii) Neoprene (b) Tetrafluoroethene
(iii) Natural rubber (c) Chloroprene
(iv) Teflon (d) Acrylonitrile
(v) Acrilan (e) Ethene

Why should the monomers used in addition polymerisation through free radical
pathway be very pure?

Which type of biomolecules have some structural similarity with synthetic
polyamides? What is this similarity?

Name the polymers used in laminated sheets and give the name of monomeric
units involved in its formation.

Which factor imparts crystalline nature to a polymer like nylon?

What is the role of benzoyl peroxide in addition polymerisation of alkenes?
Explain its mode of action with the help of an example.

What is the structural difference between HDP and LDP? How does the structure
account for different behaviour and nature, hence the use of a polymer?

Why does cis-polyisoprene possess elastic property?

To have practical applications why are cross links required in rubber?

Can nucleic acids, proteins and starch be considered as step growth polymers?

Can enzyme be called a polymer?

Why are rubbers called elastomers?

Identify the type of polymer.
—A—B—B—A—A—A—B—A—

Identify the type of polymer.
—A—A—A—A—A—A—

A natural linear polymer of 2-methyl-1, 3-butadiene becomes hard on
treatment with sulphur between 373 to 415 K and —S—S— bonds are formed
between chains. Write the structure of the product of this treatment?

What is a biodegradable polymer? Give an example of a biodegradable aliphatic polyester.

How is dacron obtained from ethylene glycol and terephthalic acid?

Identify the monomer in the following polymeric structures.

(i)

(ii)

Write the names and structures of the monomers of the following polymers:

(i) Buna-S (ii) Buna-N

(iii) Dacron (iv) Neoprene

What are the monomeric repeating units of Nylon-6 and Nylon-6, 6?

Discuss the main purpose of vulcanisation of rubber.

How does the presence of double bonds in rubber molecules influence their

structure and reactivity?

Write the name and structure of one of the common initiators used in free

radical addition polymerisation.

Write the monomers used for getting the following polymers.

(i) Polyvinyl chloride (ii) Teflon (iii) Bakelite

Define thermoplastics and thermosetting polymers with two examples of each.

Explain the term copolymerisation and give two examples.

How can you differentiate between addition and condensation polymerisation?

In which classes, the polymers are classified on the basis of molecular forces?

Is ,   , a homopolymer or copolymer?

Define the term polymerisation.

How do you explain the functionality of a monomer?

Distinguish between the terms homopolymer and copolymer and give an example of each.

What are natural and synthetic polymers? Give two examples of each type.

Explain the terms polymer and monomer.

Arrange the following polymers in increasing order of their intermolecular forces.

(i) Nylon 6, 6, Buna-S, Polythene.

(ii) Nylon 6, Neoprene, Polyvinyl chloride.

Explain the difference between Buna-N and Buna-S.

Classify the following as addition and condensation polymers: Terylene, Bakelite, Polyvinyl chloride, Polythene.

Write the names of monomers of the following polymers:

Classify the following as addition and condensation polymers: Terylene, Bakelite, Polyvinyl chloride, Polythene.

How are polymers classified on the basis of structure?

What are polymers?