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Poly(carboxylate ether)-based superplasticizer achieves workability retention in calcium aluminate cement.

ABSTRACT: Calcium aluminate cement (CAC) suffers from loss of workability in less than an hour (~15?minutes) after first touch of water. Current superplasticizers that are utilized to modify the viscosity of cement admixtures are designed to target ordinary Portland cement (OPC). The high affinity between these superplasticizers and cement particles were found to be detrimental in CAC systems. Utilization of a monomer that, instead, facilitates gradual adsorption of a superplasticizer provides workability retention. For the first time in literature, we report a superplasticizer that caters to the properties of CAC such as high rate of surface development and surface charge. While neat CAC was almost unworkable after 1?hour, with the addition of only 0.4% of the optimized superplasticizer, 90% fluidity retention was achieved.

SUBMITTER: Akhlaghi O

PROVIDER: S-EPMC5278384 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Poly(carboxylate ether)-based superplasticizer achieves workability retention in calcium aluminate cement.

Akhlaghi Omid O Menceloglu Yusuf Ziya YZ Akbulut Ozge O

Scientific reports 20170130

Calcium aluminate cement (CAC) suffers from loss of workability in less than an hour (~15 minutes) after first touch of water. Current superplasticizers that are utilized to modify the viscosity of cement admixtures are designed to target ordinary Portland cement (OPC). The high affinity between these superplasticizers and cement particles were found to be detrimental in CAC systems. Utilization of a monomer that, instead, facilitates gradual adsorption of a superplasticizer provides workability ...[more]

PMID: 28134316

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