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

ABSTRACT

Pseudorotaxane complexes between ß-CD and mPEG derivatives bearing a carboxylic acid function (mPEG-COOH) were synthesized and investigated for their dispersing properties in a cement-based mortar. The formation of mPEG-COOH derivatives and their pseudorotaxanes was investigated by 1D nuclear magnetic resonance, diffusion ordered spectroscopy, and thermogravimetric analysis experiments. Mortar tests clearly indicate that mPEG-COOH@ß-CD-interpenetrated supramolecules show excellent dispersing abilities. In addition, the supramolecular complexes show a retarding effect, analogously to other known ß-CD-based superplasticizers in which the ß-CD is covalently grafted on a polymeric backbone.