AbstractWhen benzoyl peroxide was decomposed at 90°C. inN‐allylacetamide and inN‐allylstearamide,d[M]/d[P] was about 2 andDPwas between 9 and 10, because of a wastage of benzoyloxy radicals. These radicals formed benzoic acid and benzene as a consequence of hydrogen abstraction from the amide, and the resulting amide radicals became substituted with ester and phenyl groups from the initiator.N‐butylstearamide, a saturated model forN‐allylstearamide, gave corresponding products. Rates of peroxide decomposition indicated strong induced effects, decreasing in the order:N‐allylacetamide,N‐allylstearamide,N‐butylstearamide. Slopes of the linear plots of the four products (in moles per kilogram) against initiator (in equivalents per kilogram) in the three amides in the above order were: benzoic 0.521, 0.570, 0.575; benzene 0.027, 0.086, 0.168; amide substituted by benzoate 0.459, 0.320, 0.106; amide substituted by phenyl 0.087, 0.087, 0.142. Transfer, compared to substitution, increased with chain length and decrease in unsaturation, and induced peroxide decomposition was correspondingly lowered. Thus, kinetic chain decreased with acyl chain length and decrease in unsaturation. A mechanism that postulates polar species in the transition state when amides were solvents accounted for both transfer and aromatic substitution and helped explain the difference in behavior ofN‐allylamides and allyl esters. Plots of amide entering polymer (in moles per kilogram) against initiator concentration (in equivalents per kilogram) were curves; plots of log (a–x) for amide disappearance against the same coordinate were linear. Slopes were:N‐allylacetamide −0.0742;N