Question

MCQ>>

3.Which would be useful as a fiber: (a) poly(ethylene terephthalate) or (b) poly(hexylene terephthalate)?

4.In which reaction would you expect the more “wasted loop”: the reaction of oxalyl chloride with (a) ethylenediamine or (b) 1,6-hexanediamine? 


5.Which would be the better or stronger fiber: one made from an ester of (a) terephthalic acid 
or (b) phthalic acid? 


6.Which would be more flexible: (a) poly(butylene terephthalate) or (b) poly(hexylene 
terephthalate)? 


7.Which would be higher melting: (a) a polyamine or (b) a polyester with similar members of 
methylene groups in the repeat unit? 


8.Which of the following could be a non-petrochemical plastic: (a) Bakelite, (b) urea plastics, or 
(c) melamine plastics? 


Answer 1

3. ANS :- option (a)

The answer is option (a) that is poly(ethylene terephthalate) is useful as fiber. This is because:-

• Poly(ethylene terephthalate) has an extremely high strength to weight ratio.
• Poly(ethylene terephthalate) for fiber or fabrics is strong, flexible. The stiffness of poly(ethylene terephthalate) fibers makes them highly resistant to deformation so  when they are combined with materials like cotton can reduce wrinkling, shrinking and makes the fabrics more resistant to tears.
• It is economical and has the ease of physical and chemical modification.

Option (b) that is poly(hexylene terephthalate) is not useful as fibers because :-

• It include low creep resistance and strength.
• It has insufficient ease in processing.