The polymerization of which of the following is used in the manufacturing of polythene in the industry?
(1) Methane
(2) Styrene
(3) Acetylene
(4) Ethylene
Answer: (4) Ethylene is a rather stable molecule that polymerizes only upon contact with catalysts. The conversion is highly exothermic; that is, the process releases a lot of heat. Coordination polymerization is the most pervasive technology, which means that metal chlorides or metal oxides are used. The most common catalysts consist of titanium (III) chloride, the so-called Ziegler-Natta catalysts. Another common catalyst is the Phillips catalyst, prepared by depositing chromium (VI) oxide on silica. Ethylene can be produced through radical polymerization, but this route is only limited to utility and typically requires high-pressure apparatus.
