Characterization of Size Distribution During Continuous Emulsion Polymerization: Oscillations in Vinyl Acetate Polymerization

Particle size distributions in the continuous emulsion polymerization of vinyl acetate have been predicted theoretically and measured experimentally using online measurements of turbidity spectra and offline measurements using liquid chromatography during conditions of sustained oscillations. Particle nucleation includes the dominant micellar homogeneous nucleation. Regions of instability where massive agglomeration and reactor fouling occur have been observed to appear when two generations of polymer particles coexist at low emulsifier levels and high initiator concentrations. This clearly shows the need to damp the oscillations in particle nucleation if particle stability and low wall fouling is to be achieved.