Abstract

AbstractAn experimental investigation was conducted to relate the average number of radicals per particle, n̄ to the dimensionless parameter α, as suggested by Stockmayer. Seed emulsion polymerizations of polystyrene were run over a wide range of particle sizes and initiator levels in the 50−70°C temperature range. The seed polymerization technique removed the question of particle formation behavior and allowed a straightforward determination of n̄. Alpha was varied more than three orders of magnitude and resulted in measured values of n̄ in the range 0.5−1.3. These data are in good agreement with Stockmayer's relationship as long as the value of the termination rate constant is taken at the monomer/polymer ratios found in emulsion polymerization. For polystyrene at a monomer/polymer ratio of 60/40 this value is an order of magnitude lower than that found for infinitely dilute polystyrene solutions.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call