a) The rate constant of decomposition of AIBN at 60 C, and the corresponding activation energy ,are respectively : ka= 8.5x10-652 and Ed=30 Kcal.mol-1 .calculate the half life time of this initiator at 50 C, 60 C, and 80 C b) AIBN is used to initiate the polymerization of methyl methylacrylate in benzene at 60 C. The initial concentrations are [l]o=0.02 [mol.1-4] and [M]o= 2 mol.L-1 . Assume the efficiency factor is 0.5, and termination occurs by disproportionation, Calculate The initial rate of polymerization The time at which 1/10 of monomer has been converted into polymer The conversion degree after 10 hours of polymerization. It should be checked whether the initiator consumption can be neglected. The rate of polymerization after 10 hours of reaction. Also determine the molecular weight Mn of the polymer formed initially, assuming the absence of transfer of any kind. What would be the value of Mn if the reaction medium contained 0.3 mol.L-of chlorotrimethyl silane as transfer agent, the transfer constant of which is Cr=144x104. Volume expansion of bulk monomer is neglected. Density (g/ml) Kp (60 C) Ep [Kcal.mol-1] k+x10-6 (60 C) Et [Kcal.mol-1] [I.mol. s'] 50 1.2 0.94 705 4.7