pentaerythritol, glycerol and 1,4–butane diol.
2. State two important criteria for a polymer to form a fibre.
3. Compare the molecular weight of polymer and its
distribution in free radical bulk and solution polymerisation
4. What is meant by critical miscle concentration?
5. Explain what is meant by syndiotactic and isotactic
6. What is meant by glass transition temperature?
7. Why polyacrylonitrile cannot be prepared by bulk
8. What are the materials used for the manufacture of PET
by melt polycondensation?
9. What is the function of silicone oils when used as a
compounding material for plastics?
10. What is the function of UV–stabilisers added to plastics?
polymers based on the following heads.
(ii) Thermal properties
(iii) End applications. (16)
12. (a) (i) Discuss suspension polymerisation technique in
(ii) Compare the advantages and disadvantages of emulsion
and suspension polymerisation techniques. (4)
(b) (i) Compare addition polymerisation and condensation
polymerisation with suitable examples. (8)
(ii) Compare the advantages and disadvantages of bulk and
solution polymerisation techniques. (8)
13. (a) (i) Discuss the factors affecting crystallinity and
(ii) How does crystallinity affect the properties of polymers?
Or (b) (i) Explain the various phase transitions of an amorphous
and a semicrystalline polymer. (8)
(ii) State with reasons which polymer has higher value in
each of the following pairs of polymers.
* Polystyrene or Poly ( –methyl styrene)
* Poly (methacrylate) or Poly (butylacrylate)
* Polyethylene terephthalate or Poly (bisphenol–A
* Nylon–6 or Nylon–11. (8)
14. (a) (i) Describe the manufacture of polyurethane foams
and explain the mechanisms of foam formation when water
is used as a foaming agent. (10)
(ii) How is PET manufactured and what is its uses? (6)
(b) (i) Describe the manufacture of polystyrene by bulk and
emulsion polymerization techniques and state its properties
and uses. (8)
(ii) Explain the formation of carbon fibre with suitable
reactions. (8) 15. (a) (i) State any five compounding materials with
suitable examples added to plastics and explain their
(ii) Explain the technique by which continuous polymer films
are obtained. (6)
(b) Write notes on any TWO of the following :
(i) Nylon 6, 6. (8)
(ii) Weight average molecular weight. (8)
(iii) Solubility parameter. (8)
Polymer Chemistry Anna University Previous Semester Question papers 2013