Posted by Synthetic-based plasticizers are often used in the masonry industry to improve the rheological and mechanical properties of mortar, but these systems are neither sustainable nor eco-friendly. In this study, several copolymers were prepared that contain grafted β-cyclodextrin (βCD) and its modified forms (HPβCD, βCD phosphate, Succinyl βCD, carboxymethyl βCD) were grafted onto methoxy polyethylene glycol (MPEG) and were evaluated as hybrid bio-based plasticizing admixtures for cement mortar.
At low concentrations, 1.0 wt %, the copolymers were effective plasticizers, increasing the mortar fluidity in comparison to the control sample without admixtures. At a 0.30: 1 water-to-cement ratio, the water reduction capacity was up to 20%, keeping the mortar flow within an appropriate range. Besides, hydration-related behavior was indirectly assessed through strength development and spectroscopic analyses. The mortar sample with HPβCD-MPEG had a higher compressive strength when the admixture concentration was changed from 1% (31 MPa) to 2% (40 MPa) showing the capacity of the copolymer as a strength enhancer. The copolymers Carboxymethyl βCD-MPEG (35 MPa) and βCD phosphate-MPEG (42 MPa) also reached the compressive strength typical for a 28 day mortar sample, whereas a lower value was noted for the 7 day control (30 MPa).
Compared to commercial superplasticizers, graft copolymers show high potential as sustainable alternatives to conventional non-renewable admixtures.
Andrea Gonzalez-Cordoba, Paulo César Narváez Rincón, Jairo E. Perilla, Duncan E. Cree, Lee D. Wilson; Grafted β-Cyclodextrin Methoxy Polyethylene Glycol Copolymers as Superplasticizing Admixtures for Cement Mortar. ACS Appl. Eng. Mater. 2026; https://doi.org/10.1021/acsaenm.6c01112