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Rubber Technology Centre liT Kharagpur
End Autumn Semester Examination 2012
Sub.: Science and Technology of Rubber and Rubber Like Materials
Sub. No. : RT30019
Full Marks: 100
Time: 3 hrs.
1.
Write down the i) the full name of the rubber & its chemical structure ii) Commercial process of manufacturing iii) important properties iv) vulcanization process v) application of the following rubbers (Any Four).
a)NR
b) SBR
c)MQ
d)NBR
e) IIR
(2 + 1 + 1 + 1 + 1) == 6 X 4 == 24
2. Write down the full name of the following. Mention their application in polymer science.
(Any Five)
a) Tg
c) M
n
d)ENR
e)GPC
f) 'Q'
(5 X 2) == 10
3. Answer the following
(i)
Name a rubber which has high impermeability to gases and a rubber which has got very high permeability to gases.
(ii) Name two rubbers which are vulcanized by peroxide.
(iii) Name two rubbers which are vulcanized by sulphur.
(iv) Name a polymer which has a hetero atom in the main chain and name another rubber which has unsaturation in the backbone.
(v) Name an oil resistant rubber and a highly heat resistant rubber.
(vi) Name a rubber which is a copolymer prepared via ionic polymerization.
(vii) Name two rubbers which are widely used intyre.
(viii) Name a rubber which is widely used in bio-medical application and a rubber which is used·in aero tyre.
(ix) Name two rubbers which are prepared by emulsion polymerization.
(x) Name a rubber which is widely used in oil-seal application and a rubber which is used in conveyor belt.
10 X 1 == 10
4. Write down true or false: If false, correct this (any six).
NR is an oil resistant rubber.
(i)
(ii) SBR has high permeability towards 0 2 gas.
(iii) IIR is a homopolymer.
(iv) Fluoro-elastomers have good flame retardant properties.
(v) NBR is usually used in football bladder.
(vi) Most of the rubbers are vulcanized by peroxide vulcanization.
(vii) XRD analysis is usually used to determine the glass transition temperature (Tg) of a polymer. 1x6==6
5.