FREE-RADICAL HOMOPOLYMERIZATION AND COPOLYMERIZATION OF DI-N-BUTYL ITACONATE

Di-n-butyl itaconate (DBI) was polymerized at 50 degrees C in a 3 moll (-1) benzene solution using 2,2'-azobisisobutyronitrile (AIBN) as a fr ee-radical initiator. Kinetic constants for DBI were obtained as follo ws: k(p)/k(t)(1/2) = 0.021 mol(-1/2) 1(1/2) s(-1/2), 2fk(d) = 3.62 x 1 0(-6) s(-1). Copolymerization reaction between DBI and methyl methacry late (MMA), under the same experimental conditions, was carried out an d the values of r(DBI) = 0.717 +/- 0.11 and r(MMA) = 1.329 +/- 0.09 we re found for the reactivity ratios. Applying the Q-e scheme led to Q = 0.61 and e = 0.62 for DBI. Overall copolymerization rate coefficients have been analysed on the basis of terminal and penultimate effects o n the propagation reaction. These parameters as well as the copolymer composition are not affected by total monomer concentration.