Calculation of the copolymerization parameters in the ternary copolymerization system of styrene/m‐divinyl‐benzene/p‐divinylbenzene

The r‐values of styrene with p‐divinylbenzene or m‐divinylbenzene (DVB), respectively, as determined by several authors, deviate strongly from the ideal straight line in the binary polymerization diagram. In an attempt to convert the various r‐values into coincident e‐and q‐values according to the equations of Schwan and Price. log r1 = (1 T) [6.79 (q1 ‐ q2) ‐ 3.63 1( 1 – 2)] and log r2 = (‐ 1 T) [6.79 (q1 ‐ q2) + 3.63 2 ( 1 ‐ 2)] good agreement was found for several r‐values, while others gave results that could not be evaluated. From a couple of ‐ and q‐values of p‐divinylbenzene and m‐divinylbenzene, the unmeasured r‐values between p‐divinylbenzene and m‐divinylbenzene were computed according to Schwan and Price. Using these r‐values, the ternary, copolymerization system of styrene m‐divinylbenzene/p‐divinylbenzene was computed approximately for various molar ratios of p‐divinylbenzene to m‐divinylbenzene (2:1 1:4) according to Alfrey and Goldfinger. It was shown that p‐divinylbenzene has an essential influence on heterogeneity in a ternary system, too.