Dispersing and Retarding Properties of Water-Soluble Tetrasulfonate Resorcin[4]arene and Pyrogallol[4]arene Macrocycles in Cement-Based Mortar

Abstract

Water-soluble tetrasulfonate resorcin[4]arene ( 1a and 1c ) and pyrogallol[4]arene ( 1b ) macrocycles were synthesized and investigated for their dispersing properties in cement-based mortars. Mortar tests clearly show that these polyhydroxylated macrocycles (nonpolymeric) work as cement dispersants. Setting time determinations indicate that the macrocycles 1a and 1b show a retarding effect that is reminiscent of the behavior of superplasticizers (SPs) functionalized with polyhydroxylated β-CDs. Finally, the addition of sulfate anions to the cement paste does not affect the dispersing abilities of 1b , probably due to the sulfate anion capture by H-bonding interactions with its OH groups at the upper rim.

Poly(Ethylene Glycol)/β-Cyclodextrin Pseudorotaxane Complexes as Sustainable Dispersing and Retarding Materials in a Cement-Based Mortar

“…The dispersing abilities of β-CD-based SPs is due to the steric hindrance between the truncated-cone macrocycles and the electrostatic repulsion between anionic groups of the polymer adsorbed on the surface of cement particles. − Very recently, we have found out that water-soluble resorcin[4]­arene and pyrogallol[4]­arene macrocycles show an analogous behavior and are able to work as dispersing agents but show retarding effects in cement-based mortars.…”