EFFECT OF THE STRUCTURES OF POLYCARBOXYLATE-BASED DISPERSANT ON THE VISCOSITY OF CaCO₃ SUSPENSION AND THE ADSORPTION CHARACTER OF DISPERSANT ON CaCO₃

• MORITA Tomoyuki

  HOKKAIDO UNIVERSITY, Graduate School of Engineering

• GOTOH Suguru

  HOKKAIDO UNIVERSITY, Graduate School of Engineering

• NAWA Toyoharu

  HOKKAIDO UNIVERSITY, Faculty of Engineering

Bibliographic Information

Other Title

• ポリカルボン酸系分散剤の化学構造が炭酸カルシウムへの吸着挙動と懸濁液の粘性に及ぼす影響

Abstract

Polycarboxylate-based dispersant（PC） used to disperse the suspended colloidal particles, thereby improving the fluidity of such suspensions. The driving force for dispersing of PC might be contributed by the steric repulsion arising from overlap of polymer layers of PC adsorbed on surface of colloidal particles. According to enormous past studies, the repulsion force might be represented as a function of the thickness of the layer adsorbed on the colloidal particle surface. The thickness is dependent on the conformation of PC on the suspended particles. Therefore, it is of great importance to estimate the conformation of adsorbed PC.<br/>In this study, we estimated the conformation of adsorbed polymer layer of PC using the two different models：the rheological model for prediction of adsorption layer thickness and the surface complexation model for calculation of adsorption site for PC on CC. We used fine CaCO₃ powder as the suspended particle, and three different PCs that consist of different chemical structure about side chain length.<br/>The results of this studies indicated that the thicknesses of adsorbed PCs were estimated to be the same despite length of side chain. This implies that the conformation of adsorbed PC does not agree with the previous conformation model that the main chain is adsorbed on the surface and polyethylene oxide chain is stretched into the solution in the monolayer adsorption manner. Thus it is suggested that PC which have short side chain produces self aggregation on the surface of CC and makes thicker layer than side chain length.

Journal

• Cement Science and Concrete Technology

  Cement Science and Concrete Technology 67 (1), 579-586, 2013

  Japan Cement Association

Keywords

• Polycarboxylate-based dispersant
• Calcium carbonate
• Rheology
• Adsorption
• Thickness of adsorption layer

Details

• CRID: 1390282679806355072
• NII Article ID: 130004745806
• DOI: 10.14250/cement.67.579
• ISSN: 21873313
• ISSN: 09163182
• Text Lang: ja
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed