Synthesis and properties of a novel amphoteric polycarboxylate superplasticizer

Abstract

The synthesis, characterization and properties of novel amphoteric polycarboxylate superplasticizers (PCs) are highlighted in this work. Specifically, two classes of amphoteric PCs were prepared through the addition of isobutenyl polyethylene glycol, acrylic acid and synthesized amphoteric monomer. The fluidity and fluidity retention of cement pastes containing these PCs and their adsorption behavior were investigated. In addition the cement hydration heat was measured, while X-ray diffraction and thermogravimetric behavior were also characterized. Consequently, the results indicated that these amphoteric PCs exhibited good dispersion performance and enhanced adsorption onto the cement. Furthermore, the results revealed that the PCs exerted a retardation effect during the early stages of cement hydration and subsequently accelerated this process, without affecting the subsequent cement hydration. These findings highlight the potential applications of these amphoteric PCs in concrete engineering.

GRAPHICAL ABSTRACT

The PCs exerted a retardation effect during the early stages of the cement hydration, and then accelerated this process. Impressively, the presence of the PCs did not affect the subsequent cement hydration. In comparison with other PCs, PC-5 exhibited a more significant retardation effect during the early stages of the cement hydration.

Keywords:

• Amphoteric polycarboxylate superplasticizer
• dispersing performance
• retardation effect

Acknowledgments

This research was supported by Science and Technology Planning Project of Guangzhou, China (Grant No.2016100110114).

Conflicts of interest

The authors declare there is no conflict of interest.