Radical terpolymerizations of acrylonitrile, vinyl sulfide and vinyl ether. Evaluation of reactivities of vinyl sulfide and vinyl ether toward polyacrylonitrile radical

Abstract

AbstractThe co‐ and ter‐polymerizations involving acrylonitrile (M1), vinyl sulfide (M2) and vinyl ether (M3) were investigated to compare the difference in reactivities of vinyl sulfide and vinyl ether toward attack of polyacrylonitrile radical. From the independent copolymerization results for M1/M2 and M1/M3 systems, the reactivity ratio (k12/k13) was determined as 14.7 at 60°C. This ratio was also obtained, from the treatment of the terpolymerization data, as 8.93. On comparison of these values with the previous observation according to which there was a linear relationship between log (k12/k13) and the e values of the M1 monomers, corresponding to the attacking polymer radicals M1•, the values obtained from terpolymerization were found to fit better than those obtained from simple copolymerization. From the ARRHENIUS plot of log (k12/k13), the activation energy for the reaction of ethyl vinyl sulfide with polyacrylonitrile radical was found to be 2.9 kcal/mole lower than that of ethyl vinyl ether.