Solution polymerization of vinylidene chloride using gamma radiation

Radiation induced polymerisation of vinylidene chloride in benzene and chloroform solvents was investigated to find out the effect of these solvents on the rates of polymerisation and molecular weights of the polymer formed and compared to that of the bulk polymer without the solvents. The rates of solution polymerisation and the molecular weights of the polymer were found to be lower than that of the bulk polymer indicating chain transfer to the solvents. The chain transfer constants for chloroform and benzene were found to be 1.87x10-3 and 6.95x10-3 respectively. Lower chain transfer constant value for chloroform was attributed to the fact that the abstraction of chlorine atom from chloroform by a propagating polymer radical containing two terminal chlorine atoms would be sterically hindered as compared to that from benzene. The Ksub(p)/Ksub(t)sup(1/2) values for the polymerisation of vinylidene chloride in benzene and chloroform were 4.20x10-3 and 1.48x10-3 respectively. The results are discussed in detail. (author)