| Abstract
| - The kinetics of the 60Co γ ray-initiatedinverse emulsion polymerization of aqueous sodiumacrylate solutions in kerosene with Span 80 as the emulsifier wasinvestigated. The conversion−timecurves were analyzed using the equation [εx/(1 − ε)− ln(1 − x)] = B (constant) +[n̄kp/(Vp∞NA)]t,derivedon the basis of a monomer droplet nucleation mechanism. Thefollowing expressions were obtained forK =[n̄kp/(Vp∞NA)]under the experimental conditions investigated: K ∝[dose rate]0.9[sodiumacrylate]0.5[Span 80]0.4, which was simplified to n̄∝ [dose rate]0.9, n̄kp ∝[sodium acrylate]0.5, andn̄/Vp∞ ∝[Span80]0.4. The polymerization rate during the steadystate (approximate conversion range 20−80%) couldbe expressed by Rp =KxC0 ∝ [doserate]0.9[sodium acrylate]1.5[Span80]0.4. The kinetic analysis suggestsa dose rate independent polymerization process for the system studiedsuch that, at any time, there wasonly one active passage of radiation through a droplet, viz., allpolymer radicals resulting from a radiationpassage were terminated before another passage.
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