Reactivity ratios and thermal and dielectric studies of n-butyl methacrylate and methacrylamide copolymers

Free‐radical copolymerization of n‐butyl methacrylate (B) and methacrylamide (M) was carried out in the presence of 2,2'‐azobisisobutyronitrile (AIBN) in dimethyl formamide (DMF) at 60°C. The percentage composition of the copolymers was established by elemental analysis. The reactivity ratios as determined by the Finemann—Ross (F—R) and the Kelen–Tüdős (K—T) methods are r1 (B) = 2.75 ± 0.01, r2 (M) = 0.2 ± 0.01 and r1 = 2.70 ± 0.05, r2 = 0.19 ± 0.02, respectively. The copolymers were characterized by IR, 1H‐NMR, thermal, and dielectric studies. Glass transition temperature (Tg) values were determined by DSC. Dielectric studies were carried out to understand the segmental motions and the effect of composition on dielectric loss. © 1993 John Wiley & Sons, Inc.