Abstract
A study of the effects of the copolymerization ratio and polymerization degree of sodium styrenesulfonate-sodium methacrylate copolymers, P (NaSS-NaMAA), on the removal efficiency and redeposition of Fe2O3 particulate soil in hard water, at pH 10, 30°C, to obtain a phosphate builder substitute was carried out.
The ζ-potentials of Fe2O3 particles from soiled nylon fabric in washing liquor were measured by microelectrophoresis to investigate the electric potential effects of the builder on particulate soil removal.
Removal efficiency and redeposition of particles were found to be influenced more by electrokinetic phenomena than chelating action under alkaline washing conditions such as dilute concentration of P (NaSS-NaMAA), 50100 ppm water hardness. Thus P (NaSS-NaMAA), a multivalent polyelectrolyte, removes soil primarily through electric and steric barrier effects. The polymerization degree of P (NaSS-NaMAA) noted to be a more important factor than the copolymerization ratio. The optimum P (Nass-MaAA) having the copolymerization ratio of 3 : 7, and a molecular weight of 1.5×104, showed a builder effects far superior to STP in solution containing a surfactant such as DBS or APE.
