solvent effects on the free-radical polymerization of methyl methacrylate-styrene system

Abstract EN

The free radical copolymerization of the methyl methacrylate (MMA)-styrene (Sty) system is studied in cyclohexanone, cyclohexanone-cyclohexane (1:1.16 by volume) m،xture, and cyclohexane at 60°c ± l°c using benzoyl peroxide initiator.

The reactivity ratios are evaluated by Yezrielev, Brokhina, and Roskin (YBR), Kelen and TudOs (KT), and £rror-in-variable model (EVM) methods.

The r-parameter values are in reasonable agreement with those reported in the literature for the free radical copolymerization of the present monomer system.

The ^product values suggest the alternating tendency of the monomers in copolymerization.

The increasing dielectric constant of the reaction medium does not influence the reactivity ratios, particularly the ٢٤ value which is also evident from Q-e parameters.

Moreover, the conditional probabilities governing se؟uence distribution are unaffected by the polymerization medium.

These factors support the operation of a bootstrap model.