Effect of carboxylate content in comb-like AA–IPEG copolymer as a dispersant for cement-based systems
| Autor: | Ming Li, Yan Zhu, Dan-Dan Zheng |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Cement
Materials science 0211 other engineering and technologies Maleic anhydride 02 engineering and technology Building and Construction 021001 nanoscience & nanotechnology Dispersant chemistry.chemical_compound chemistry Chemical engineering 021105 building & construction Zeta potential Copolymer Organic chemistry General Materials Science Carboxylate Fourier transform infrared spectroscopy 0210 nano-technology Acrylic acid |
| Zdroj: | Advances in Cement Research. 29:387-396 |
| ISSN: | 1751-7605 0951-7197 |
| Popis: | AA–IPEG comb-like copolymer is a kind of polycarboxylate-based dispersant for cement-based systems. Copolymers with different carboxylate contents were synthesised using isoprenyl oxy polyethylene glycol ether (IPEG) and acrylic acid (AA) as raw materials, further modified with maleic anhydride. The copolymers were characterised by Fourier transform infrared spectroscopy, gel permeation chromatography and surface tension measurements. The dispersion of cement paste mixed with copolymer was studied by means of the zeta potential, adsorption behaviour, cement paste fluidity, setting time and scanning electron microscopy. It was found that the copolymer with a higher carboxylate content exhibited lower adsorption on the surface of cement particles and more negative zeta potential, and resulted in longer retention dispersion and setting time at the same dosage; however, excessive carboxylate content decreased the dispersing force of cement particles. Therefore, for more efficient dispersants for cement-based systems, there is a proper proportion between carboxylate content and poly(ethylene oxide) chains as the side groups on backbone chains. |
| Databáze: | OpenAIRE |
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