Solution properties of poly(N,N‐dimethylacrylamide)

In connection with the research on the influence of the substituents on the intrinsic configurational character of the polymers of the derivatives of acrylic acid as related to the solution properties, experiments have been made on poly(N,N‐substituted acrylamides). In the present paper the results obtained by light scattering and viscosity on the behavior in methanol at 25°C. and in water at 25 and 40°C. of unfractionated samples of poly(N,N‐dimethylacrylamide) with molecular weights ranging from 5 × 104 to 1.2 × 106 are reported. The intrinsic viscosity‐molecular weight relationships for the polymer dissolved in the three solvents are reported, as well as the viscometric constant Ki in ideal solution and the (ri2/M)1/2 ratio which characterize the polymer. By comparing the value of the (ri2/M)1/2 ratio for poly(N,N‐dimethylacrylamide) with those already reported for poly(methyl acrylate) and poly(acrylic acid) and other nonionic polymers, it is shown that the N(CH3)2 groups have practically no influence upon the configurational character of the polymer chain.