[HYDROXY(TOSYLOXY)IODO]BENZENE AS THERMAL INITIATOR FOR THE RADICAL POLYMERIZATION OF METHYL-METHACRYLATE

The thermal polymerization of methyl methacrylate in a solution of N,N -dimethylacetamide has been studied using [hydroxy(tosyloxy)iodo] benz ene (HTIB) as the initiator. The rate of polymerization was a direct f unction of the monomer and initiator concentrations. The initiator and monomer exponent values expressing this dependence were found to be 1 .0 and 0.8, respectively. The overall activation energy of polymerizat ion was estimated to be 45 kJ.mol-1. The polymerization was inhibited in the presence of hydroquinone. The effect of various solvents on the polymerization rate was studied. The polymer prepared with HTIB (0.47 x 10(-3) mol.L-1) had a number-average molecular weight of 138,000 an d a glass transition temperature of 106-degrees-C. The polymer showed good thermal stability as determined by thermogravimetric analysis.