Number average molecular mass (${\overline{\mathrm{M}}}_{\mathrm{n}}$) and mass average
mol. mass (${\overline{\mathrm{M}}}_{\mathrm{w}}$)of synthetic polymers are related as:

(1) ${\overline{\mathrm{M}}}_{\mathrm{n}}$ < ${\overline{\mathrm{M}}}_{\mathrm{w}}$

(2) ${\overline{\mathrm{M}}}_{\mathrm{n}}$ > ${\overline{\mathrm{M}}}_{\mathrm{w}}$

(3) ${\overline{\mathrm{M}}}_{\mathrm{n}}$ = ${\overline{\mathrm{M}}}_{\mathrm{w}}$

(4) M_n > M_w

Which of the following is wrong?

1. PMMA is called plexiglass

2. PTFE is called teflon

3. SBR is called natural rubber

4. LDPE is called low density polyethylene

Nylons, polyesters, and cotton, all possess strength due to:

1. intermolecular H-bonding

2. van der Waals’ attraction

3. dipole-dipole interaction

4. None of the above

PDI for natural polymers is generally close to:

(1) zero                             

(2) 100

(3) 1                                   

(4) 10

The catalyst used in the manufacture of polythene by the Ziegler method is:

1. titanium tetrachloride and triphenyl aluminum

2. titanium tetrachloride and triethyl aluminium

3. titanium dioxide

4. titanium isopropoxide

 Which of the following is a step-growth polymer?

1. Bakelite

2. Polyethylene

3. Teflon

4. PVC

The initial reaction in the formation of bakelite is an example of:

(1) Aromatic electrophilic substitution.

(2) Aromatic nucleophilic substitution.

(3) Free radical reaction.

(4) Aldol reaction.

PMMA is the polymer of.

1. methylmethacrylate

2. methylacrylate

3. methacrylate

4. ethylacrylate

Condensation of caprolactam gives:

1. nylon-6,6               
2. nylon-6
3. nitrile rubber
4. nylon-6,10
 

Natural rubber has

1. All trans-configuration.

2. Alternate cis - and trans-configuration.

3. Random cis - and trans-configuration.

4. All cis-configuration.