“…34 However, if the cellulose is cross-linked by a difunctional reagent before introduction of the ionic group, May 1981 85 fiber structure is retained and a much higher capacity may be reached. Guthrie and Bullock 35 have tested about 30 potential cross-linking agents and found di(2-sulfatoethyl)amine, 1,4-disulfatobutane, 1,3-dichloro-2-propanol, divinylsulfone, and formaldehyde to be very suitable for this purpose.…”