Reactivity ratios of styrene and methyl methacrylate at 90°C

Abstract

AbstractFrom the conversion–composition data of Gruber and Elias, the reactivity ratios of styrene (M1) and methyl methacrylate (M2) were calculated to be r1 = 0.55 ± 0.02 and r2 = 0.58 ± 0.06 at 90°C. The least‐squares method was then used on these and literature values at other temperatures to obtain the Arrhenius expressions: In r1 = 0.04736 – (235.45/T), and ln r2 = 0.1183 – (285.36/T). Using literature values for the homopolymerization steps, A11 = 2.2 × 107l./mole‐sec., E11 = 7.8 kcal./mole, and A22 = 0.51 × 107 l./mole‐sec.−1, E22 = 6.3 kcal./mole, activation energies and frequency factors were then calculated for the cross‐polymerization steps: A12 = 2.1 × 107 l./mole‐sec., E12 = 7.3 kcal./mole, and A21 = 0.45 × 107 l./mole‐sec., E21 = 5.7 kcal./mole.