METHOD FOR PRODUCTION OF COMPLEX MODIFIER OF CONCRETE MIXTURE Russian patent published in 1997 - IPC

FIELD: production of complex modifiers on the base of microsilica. SUBSTANCE: method involves wetting of microsilica, its mixing with superpeptizing agent on the base of salt of condensation product of β-naphthalene sulfoacid and formaldehyde and adjustment powder product to moisture content. During mixing nitrilotrimethyl phosphonic acid is additionally added and wetting by water is carried out till suspension has composition is obtained. Suspension comprises, mas. %: microsilica, 40-70; superpeptizing agent on the base of salt of condensation product of β-naphthalene sulfoacid and formaldehyde, 4.0-9.5; nitrilotrimethyl phosphonic acid, 0.01-0.40; water, the balance. Adjustment to moisture content 1-8 % is carried out with the help of drying in air stream, the process takes place at 160-300 C. Complex modifier has stable characteristics, it provides retaining of concrete mixture plasticity within at least 60 min. EFFECT: improved efficiency; improved quality. 2 tbl