The repeating units of PTFE are -

1. ${\mathrm{F}}_2\mathrm{C} = {\mathrm{CF}}_2$

2. $\mathrm{FCl} \mathrm{C}\hspace{0.17em}= {\mathrm{CF}}_2$

3. ${\mathrm{F}}_3\mathrm{C} - {\mathrm{CF}}_3$

4. ${\mathrm{Cl}}_2\mathrm{CH} - {\mathrm{CH}}_3$

Low-density polythene is prepared by -

1. Free-radical polymerization.

2. Cationic polymerization.

3. Anionic polymerization.

4. Ziegler-Natta polymerization.

Which of the following is a synthetic polymer?

1. Phenol-formaldehyde resin.

2. Proteins.

3. Polysaccharides.

4. Natural rubber.

Bakelite is produced by : 

1. Phenol, methanol

2. Phenol, NaOH

3. Phenol, urea

4. Phenol, formaldehyde

Treatment of rubber with sulfur -

(1) Annealing.

(2) Vulcanization.

(3) Quenching.

(4) None of the above.

Teflon, polystyrene, and neoprene are all -

1. Monomers.

2. Co-polymers.

3. Homopolymers.

4. Condensation polymers.

Polymer that contains isoprene units is : 

(1) Natural rubber

(2) Nylon-6, 6

(3) Polyethylene

(4) Dacron

PVC as obtained after polymerization is -

1. Soft and pliable.

2. Hard, brittle, and transparent.

3. Hard and infusible.

4. None of the above.

The compound used in the manufacture of terylene is: 

1. Ethylene

2. Vinyl chloride

3. Ethylene glycol

4. Adipic acid

A polymer of methylene chloride and sodium polysulfide is?

(1) Thiokol

(2) Melamine

(3) Glyptal

(4) Perlon L