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
A polymer of acrylonitrile is called:
1. Saran
2. Orlon
3. Dacron
4. Tetron
Which one of the following pairs is not correctly matched?
1. Terylene—condensation polymer of terephthalic acid and ethylene glycol
2. Teflon—thermally stable cross-linked polymer of phenol and formaldehyde
3. Perspex—a homopolymer of methyl methacrylate
4. Synthetic rubber —a copolymer of butadiene and styrene