Factors affecting the Mobilities of Anions in Nylon

IT has been reported1,2 that the diffusion coefficients of anions in nylon rapidly increase with increasing internal concentration. In the case of the trisulphonic dye naphthalene scarlet 4R, McGregor, Peters and Petropolous2 attributed this result to a proportionality between the diffusion coefficient and some power of the activity coefficient of the anion. Atherton and Peters3 modified the Gilbert-Rideal theory4 (originally developed to explain the sorption of inorganic acids by wool) so as to cover polyvalent dyes in nylon; they obtained anion activity coefficients of the form [1/(1 − θA)], where θ is the fraction of occupied amine sites.