The influence of poly(styrene sulfonate) addition to cellulosic fibers by wet processing on the physicomechanical properties of paper

The study of the effect of sodium poly(styrene sulfonate) addition to suspensions of fibers, in the presence of aluminum salts as adsorption aids, revealed the retention effect of fine solids during sheet formation. Polyelectrolyte adsorption also causes an increase of bounding energy in the web. It is shown that the improvement observed for the dry strength properties of paper is a consequence of these two effects. (In this paper the words “fine solids” or “fines” indicate the parts of the cellulosic material which filtrates through a 150-mesh screen, regardless of its nature.)