Answer the followings over 45 minutes. Some questions might have more than one answer.
1. Select the correct statement from the following options.
a) Chain growth polymerisation requires the presence of double bond in monomer
b) Chain growth polymerisation requires more than one active radical centre to propagate.
c) In chain growth polymerisation, rate is proportional to square of initiator concentration.
d) In chain growth polymerisation, polymer MW rises steadily towards the end of reaction
2. Select the incorrect statement from the following option.
a) Step growth polymerisation requires two reactive functional groups to be present at both ends of
the monomer
b) No by-product is formed in condensation polymerisation
c) In condensation polymerisation, growth of chain occurs at minimum of the two active centres
d) In condensation polymerisation, polymer MW rises steadily towards the end of reaction
3. The Ziegler Natta catalyst use titanium halide because
a) titanium provide a nucleophile centre
b) titanium can form resonance stabilization with the α-olefin monomer
c) titanium can accept electron pair from the α-olefin monomer
d) titanium induce formation of free radical during polymerisation
4. Two monomer of very large different in reactivity ratio will form what type of copolymer?
a) Alternate
b) Graft
c) Random
d) Block
5. Which of the following act as an initiator in free-radical polymerisation?
a) Grignard reagent
b) Lewis acids
c) Benzoyl peroxide
d) Potassium amide
6. Which of the following act as a curing agent in formation of cured epoxy?
a) triethylene tetraamine
b) Lewis acids
c) Benzoyl peroxide
d) AIBN
7. The temperature at which curing of polyimide is carried out is
a) 1000C
b) 500C
c) -1000C
d) 2500C
8. Rate of radical polymerisation is sensitive to changes in the temperature because
a) it favour formation is disproponation reaction
b) It generate more free radicals
c) it favours cross-propagation during copolymerisation
d) it act as inhibitor during propagation step
9. Which of the following monomer cannot be polymerised by radical polymerisation?
a) Butadiene
b) Bisphenol A
c) Vinyl chloride
d) Acrylates
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10. In polycondensation between ethylene glycol and terephthalic acid, the nucleophile is
_________ and the leaving group is ____________
a) ethylene glycol, water
b) terephthalic acid, ethylene glycol
c) terephthalic acid, water
d) ethylene glycol, terephthalic acid
11. Hydrosilylation is
a) Curing reaction of polyimide
b) Condensation between diisocynate and polyol
c) Polymerisation between styrene monomer under radical mechanism
d) Preparation of polysiloxane between a vinyl and hydrosilyl functional group
12. Which of the following is used for making foam structure?
a) Ethylene glycol
b) Polyethylene terephthalate
c) Hexamethylene diamine
d) Styrene butadiene
13. Pheno and formadehyde is used to produce a thermoplastic material .
a) True
b) False
14. Which of the following technique is used to separate a solid product from solid impurities
a) Vacuum filteration
b) Centrifuge
c) Reflux
d) fractional distillation
15. Suggest a type of copolymer between two different monomer having Q values almost similar but
large polarity e values?
a) Alternate
b) Block
c) Random
d) Graft
16. Choose an incorrect statements below:
a) In blend, there is a strong secondary forces between two different polymer chains
b) In blend there is a strong covalent bond between two different monomer
c) In copolymer there is a strong covalent bond form between two different polymer chains
d) In copolymer there is a strong covalent bond form between two different monomer
e) In composite there is a strong secondary forces between the filler and the polymer matrix.
17. X and Y monomer are expected to from random colopymer due to following reasons except
a) their respective reactivity ratio is almost 1
b) their respective reactivity ratio is very small
c) formation of their respective radical intermediate is stable
d) their respective radical intermediate can undergo resonance stabilization
18. What is the name of additive added into monomer mixture to delay polymerization process
a) transfer agent
b) crosslinker
c) inhibitor
d) retader
e) chain extender
19. During reflux in purification step in polymerization, the solvent selected is based on
a) boiling poiling
b) melting point
c) solubility
d) density
20. Cross-linking of polymer chains affect the followings except
a) induce high level of crystallinity
b) induce high level of glass transition
c) induce high tensile strength
d) induce chain rigidity