Answer: (iii) Dacron
Dacron is a condensation polymer. The condensation polymers are formed by repeated condensation reaction between two different bi-functional or tri-functional monomeric units. In these polymerisation reactions, the elimination of small molecules such as water, alcohol, hydrogen chloride, etc. takes place.
Features of Dacron
Listed below are few features of Dacron
- Dacron is a linear polymer that usually comprises about 80 units per chain, a solid which can be melted without decomposition.
- The molten polymer is forced through tiny holes in a spinneret and cools and solidifies in the form of thin fibres.
- Dacron is also chemically resistant and absorbs less water than the undrawn polymer. For the same reason, it is difficult to dye Dacron, since the dye molecules cannot find room between the polyester chains.
- In the form of a film, Dacron polyester, polyethene terephthalate, is known commercially as Mylar.