### Abstract

Original language | English |
---|---|

Pages (from-to) | 104-112 |

Number of pages | 9 |

Journal | Journal of Colloid and Interface Science |

Volume | 332 |

Issue number | 1 |

DOIs | |

Publication status | Published - 2009 |

MoE publication type | A1 Journal article-refereed |

### Fingerprint

### Keywords

- Colloidal suspensions
- Calcite
- Shear modulus
- Ordered lattice
- Particle interactions
- DLVO

### Cite this

*Journal of Colloid and Interface Science*,

*332*(1), 104-112. https://doi.org/10.1016/j.jcis.2008.12.034

}

*Journal of Colloid and Interface Science*, vol. 332, no. 1, pp. 104-112. https://doi.org/10.1016/j.jcis.2008.12.034

**Shear modulus of colloidal suspensions : Comparing experiments with theory.** / Eriksson, Rasmus; Pajari, Heikki; Rosenholm, Jarl B. (Corresponding Author).

Research output: Contribution to journal › Article › Scientific › peer-review

TY - JOUR

T1 - Shear modulus of colloidal suspensions

T2 - Comparing experiments with theory

AU - Eriksson, Rasmus

AU - Pajari, Heikki

AU - Rosenholm, Jarl B.

PY - 2009

Y1 - 2009

N2 - In this work, the experimentally determined shear modulus of a colloidal suspension has been compared to a calculated shear modulus based on an ordered lattice model. The experiments were performed on a well characterized calcite suspension. The calcite suspension was confirmed to be in a flocculated state, thus exhibiting strong elastic character. The experimental shear modulus was estimated from the elastic modulus in the linear viscoelastic region. This is contrary to established convention, where the high frequency limiting modulus is used. However, the network structure breaks down at high frequencies, resulting in a different system. Therefore the shear modulus was estimated from the response of the intact particle network structure, which resides within the linear viscoelastic region. Calculation of the shear modulus is based on an ordered lattice model, where the particles are arranged in regular 3D-arrays. Interaction forces between the particles are also considered, based on the well known DLVO-theory. Calculations of the shear modulus for flocculated colloidal suspensions are not trivial however, because of the random distribution of particles. Due to this fact the average interparticle distance is impossible to determine exactly and therefore the comparison between experimental and calculated shear modulus was made by calculating the shear modulus as a function of interparticle separation. Some different models for interaction forces between particles were tried, and the results were compared to rheological data. These preliminary results show that useful suspension properties can be evaluated by combining rheological measurements with theories for interactions between particles arranged in ordered lattices.

AB - In this work, the experimentally determined shear modulus of a colloidal suspension has been compared to a calculated shear modulus based on an ordered lattice model. The experiments were performed on a well characterized calcite suspension. The calcite suspension was confirmed to be in a flocculated state, thus exhibiting strong elastic character. The experimental shear modulus was estimated from the elastic modulus in the linear viscoelastic region. This is contrary to established convention, where the high frequency limiting modulus is used. However, the network structure breaks down at high frequencies, resulting in a different system. Therefore the shear modulus was estimated from the response of the intact particle network structure, which resides within the linear viscoelastic region. Calculation of the shear modulus is based on an ordered lattice model, where the particles are arranged in regular 3D-arrays. Interaction forces between the particles are also considered, based on the well known DLVO-theory. Calculations of the shear modulus for flocculated colloidal suspensions are not trivial however, because of the random distribution of particles. Due to this fact the average interparticle distance is impossible to determine exactly and therefore the comparison between experimental and calculated shear modulus was made by calculating the shear modulus as a function of interparticle separation. Some different models for interaction forces between particles were tried, and the results were compared to rheological data. These preliminary results show that useful suspension properties can be evaluated by combining rheological measurements with theories for interactions between particles arranged in ordered lattices.

KW - Colloidal suspensions

KW - Calcite

KW - Shear modulus

KW - Ordered lattice

KW - Particle interactions

KW - DLVO

U2 - 10.1016/j.jcis.2008.12.034

DO - 10.1016/j.jcis.2008.12.034

M3 - Article

VL - 332

SP - 104

EP - 112

JO - Journal of Colloid and Interface Science

JF - Journal of Colloid and Interface Science

SN - 0021-9797

IS - 1

ER -