(197bm) Computational Investigation of Interfacial Transport in Bijels

The University of Oklahoma, Norman, OK 73071

Bicontinuous Interfacially Jammed Emulsion Gels, also known as Bijels, find many applications in the industry including catalysis, separation processes and tissue engineering [1]. Recently, they have been considered as options for reactive separation media due to their large interfacial areas and ease of removal and insertion of reagents and products. In this work, polymer transport through Bijel structure is investigated through the use of Dissipative Particle Dynamics (DPD) computations, which is available through the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) software package [2-5]. The two fluid phases are water and diethyl phthalate, stabilized with neutrally wetting nanoparticles. Surface parameters, such as interfacial tension and contact angle, are measured using the DPD coarse grained simulations in order to validate the computations and to guarantee Bijel stability [6]. Thereby, the interactions between the immiscible phases and the jammed nanoparticles can be evaluated. By the insertion of intra-bead interaction potentials, a multimeric molecule is modelled in DPD focusing on conformation identities such as the radius of gyration. The presentation will focus on the selection of the DPD model parameters that mostly affect the multimer conformation properties as a function of DPD beads. The discussion will include the calculation of the multimer diffusivity in each of the water and oil phases, and then the diffusivity across the oil-water interface. The mass transport coefficient as a function of the polymer-solvent interactions and the interfacial tension on the bijel system is obtained in order to model the migration of lipophilic compounds from the water to the oil phase.

ACKNOWLEDGEMENTS

The support of NSF under grant EFRI-2132141 is gratefully acknowledged as the use of computing facilities at the University of Oklahoma Supercomputing Center for Education and Research (OSCER) and at XSEDE (under allocation CTS-090025).

REFERENCES

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