Persulfate‐initiated polymerization of acrylamide

A dilatometric technique was used to obtain conversion–time data for the polymerization of acrylamide initiated by potassium persulfate in water. The results are summarized by the empirical rate expression, − d [M 1 ]/ dt = R p = k 1.25 [K 2 S 2 O 8 ] 0.5 [M 1 ] 1.25 , and k 1.25 = 1.70 × 10 11 exp {−16,900/ RT } 1. 0.75 /mole −0.75 ‐min. Persulfate was varied over the range 9.5 × 10 −4 to 5.2 × 10 ×2 mole/l., and initial monomer concentration [M 1 ] was varied from 0.05 to 0.4 mole/l. The temperature range was 30−50°C. Results of analysis of the kinetics and energetics of the polymerization favor a cage‐effect theory rather than a complex‐formation theory to explain the order with respect to monomer.