Thermosetting plastics are:
1. Cross-linked polymers
2. Don’t melt or soften on heating
3. Cross-linking is usually developed at the time of moulding where they harden irreversibly
4. All of the above
Which are true for terpolymer?
(1) Contains three monomers
(2) ABS plastic
(3) A polymer of acrylonitrile, butadiene and styrene
(4) All of the above
Which is/are true for elastomers?
1. These are synthetic polymers possessing elasticity
2. These possess very weak intermolecular forces of attractions between polymer chains
3. Vulcanised rubber is an example of elastomer
4. All of the above
If N1, N2, N3,.... are the number of molecules with molecular masses M1, M2, M3..... respectively, then mass average molecular mass is expressed.
1.
2.
3.
4.
A copolymer of vinyl chloride and vinyl acetate is called:
1. Vinylon
2. Saran
3. Dynel
4. Orlon
In vulcanisation of rubber:
(1) Sulphur reacts to form new compound.
(2) Sulphur cross-links are introduced which resists wear and tear due to friction.
(3) Sulphur forms a very thin protective layer over rubber.
(4) All of the above.
The starting materials of PCTFE are:
(1) monochloro trifluoro ethylene
(2) tetrafluoroethylene
(3) vinyl chloride
(4) styrene
The abbreviation PDI refers to:
(1) name of the polymer
(2) polydispersity index of polymer
(3) application of polymer
(4) poly diagonal index
Caprolactam can be obtained from:
(1) benzaldehyde
(2) cyclohexane
(3) benzophenone
(4) adipic acid
The monomer units of silicons a water repellant, acid resistant and heat resistant polymer is:
1. Si
2. SiO2
3. R2SiO
4. None of these