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Superplasticizer is one type of chemical cement admixtures used to improve initial workability and improve the performances of high strength concretes.They are made of polymers with carboxylate (PolyCarboxylates Ethers,PCEs), sulfonate (NaphtaleneSulfonate, NSF) and phosphonate (new phosphonate based PHN) groups.In the first stage of cement hydration, superplasticizers are dissolved and physisorbed onto the surface of anhydrous cement grains to prevent aggregation so as to increase the fluidity of cement.During the cement hydration process, AFm phases, which consists of hydrated calcium aluminates based on the layered double hydroxide (LDH)-like structure [Ca2Al(OH)6]·X·nH2O, precipitate with X an anionic species.Previous studies have shown that part of superplasticizer can be immobilized by the formation (definitive or transient) of a hybrid-AFm phase,thereby reducing their efficiency.The intercalation of superplasticizer into the AFm structure refers to their anionic functional groups.We have characterized the reactivity of three benzene derivatives with regard to AFm formation: C6H5-R, where R =CO2, SO3 and PO32-.These model molecules were used to investigate the interface between the anionic groups and the positive [Ca2Al(OH)6]+ rigid main layer.Co-precipitation and ion exchange methods (using the precursor AFm-NO3) were applied to prepare AFm hybrid phases.The influence of different experimental parameters, such as the organic molecule concentration, pH value, temperature, drying method and washing method has been investigated.The as-prepared samples were characterized by X-ray diffraction, FT-IR spectroscopy, Raman spectroscopy, complexometric titration and thermal analyses.