ADDITIVE SYSTEM INCLUDING A POLYALKOXYLATED PHOSPHONATE, A POLYALKOXYLATED POLYCARBOXYLATE AND A RETARDING AGENT, AND USE THEREOF

摘要

The disclosure relates to an additive system for a hydraulic composition including: at least one polyalkoxylated phosphonate polymer; at least one polyalkoxylated polycarboxylate polymer; and at least one retarding agent of formula (I): C1R′H(OH)[CH(OH)]nC(O)O1R (I) for improved maintenance of the rheology of hydraulic compositions of Portland cement.

主权项

1. An additive system configured to thin a hydraulic composition, the additive system comprising:
at least one polyalkoxylated phosphonate polymer; at least one polyalkoxylated polycarboxylate polymer; and at least one setting retarder of formula (I):
C1R′H(OH)[CH(OH)]nC(O)O1R   (I)wherein
R′ represents H; R represents H, an ammonium, an amine group or an alkali or alkaline-earth metal; or R and R′ are missing and C1 and O1 are connected by a covalent bond so as to form a polyhydroxylactone cycle n represents an integer comprised between 2 and 6, wherein the hydraulic composition comprises Portland cement, optionally mixed with mineral additions chosen from among slags, pozzolanic materials, fly ash, burnt shales, limestones, silica fumes, metakaolins, siliceous additions, or mixtures thereof, and wherein, when the additive system is added to the hydraulic composition, fluidity of the hydraulic composition is maintained over durations greater than or equal to 90 minutes.