A monomer Z is polymerized in the presence of an initiating system Y. The follow
ID: 3164211 • Letter: A
Question
A monomer Z is polymerized in the presence of an initiating system Y. The following experimental observations are made:
a. The degree of polymerization decreases as the reaction temperature increase.
b. The degree of polymerization is affected by the solvent used.
c. The degree of polymerization is first-order in monomer concentration.
d. The rate of polymerization increases as the reaction temperature increases.
Is this polymerization proceeding by a step, radical chain, cationic chain or anionic chain mechanism? Discuss briefly how each experimental observation is consistent with your answer.
Explanation / Answer
In radical chain reaction rate is favoured at low temperatures. therefore first step is satsfied.
in the radical reaction solvent, initiator , polymer P, and added chain transfer agent T comes into picture.
,the rate of chain propagationis generally described using a function of the initiator and monomer concentration and hence the degree of polymerization is said to be the first order in monomer concentration.
the rate of polymerization and reaction temperature are propotional and
the polymerisation is hence proceeded as a radical chain.