| Abstract: | The kinetics of the free radical copolymerization of diethyl maleate (M1) with methyl methacrylate (M2) was studied in bulk at 60°C with azoisobutyronitrile (AIBN) as initiator. The reactivity ratios of the system were determined by means of 1H NMR spectroscopy. The obtained values show that diethyl maleate is not only unable to homopolymerize (r12 = 0) but also display a very low tendency to incorporate in the polymer chain (r21 = 370) under the present conditions. Molecular weight measurements showed that a normal, although very slow growth reaction involving diethyl maleate takes place. Therefore, chain transfer could be neglected in the kinetic analysis. The dependence of the initiation rate constant on the monomer feed was analysed by means of the inhibition method. An equation for describing the observed dependence of polymerization rate on feed composition was derived taking into account the influence of solution viscosity on the termination rate constant (diffusion theory). |
