Emulsion-precipitation polymerization of diisopropyl fumarate

The emulsion polymerization of diisopropyl fumarate initiated with a redox initiator and an anionic emulsifier was investigated. The study:includes co nversion and particle number determinations as a function of time, temperat ure and the concentrations of initiator, emulsifier and monomer. The reacti on is characterized by a limiting conversion following a linear increase of the conversion with time from the beginning on. The reaction rate is very much higher than those obtained in bulk or in solution polymerization. Taking into account the results and the response of the system to an additi on of styrene and toluene, a mechanism of radical occlusion together with a diffusion-controlled propagation in the polymer matrix is proposed. The ve ry high apparent activation energies for the propagation and limiting conve rsion suggest a complex behavior.