Abstract
Bridging flocculation of colloidal particles by adsorbing polymer is simulated in three dimensions by an off-lattice Monte Carlo model. Polymer chains are modelled as freely jointed, freely rotating, excluded volume random walks of 50 segments in length. Two types of particle-particle interaction are modelled: (i) hard-sphere repulsions, and (ii) soft-sphere repulsions. Particles and polymer interact via a square-well potential. Numerical results are presented for the effects of square-well depth and particle-particle interaction on the conformation of adsorbed polymer and the structure of particle flocs that are formed. The floc structures obtained from modelling particles with soft-sphere repulsions are compared to experimental data from small-angle neutron scattering studies, obtained from the literature. Soft-sphere repulsive interactions results in less compact floc structures, which have a more short-range, fluid-like character than those formed from hard spheres. The structure of flocs obtained from modelling soft spheres is more reminiscent of the floc structure found in experimental systems.
Original language | English |
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Pages (from-to) | 231-242 |
Number of pages | 12 |
Journal | Colloids and Surfaces |
Volume | 62 |
Issue number | 3 |
Publication status | Published - 5 Feb 1992 |