Controlled degradation of hydrogels enables several applications of these materials, including controlled drug and cell release applications and directed growth of neural networks. These applications motivate the need of a simulation framework for modeling controlled degradation in hydrogels. We develop a Dissipative Particle Dynamics (DPD) framework for hydrogel degradation. As a model hydrogel, we prepare a network formed by end-linking tetra-arm polyethylene glycol precursors. We model bond breaking during degradation of this hydrogel as a stochastic process. The fraction of degradable bonds follows first order degradation kinetics. We characterize the rate of mass loss during degradation process.

Using dissipative particle dynamics approach, we model phase separation in a ternary system encompassing cross-linked polyacrylamide (PAM) gel, oil and water. PAM gels are widely used in many applications, from food and cosmetic applications to enhanced oil recovery approaches. We show that the PAM nanogel adsorbs at the oil-water interface and spreads out over this interface for the case of a loosely cross-linked polymer network. Tailoring PAM behavior at the oil-water interfaces by controlling gel’s properties could allow one to alter the properties of oil-water emulsions.

Via the Dissipative Particle Dynamics (DPD) approach, we study the self-assembly of hybrid structures comprising lipids and end-functionalized nanotubes. Individual lipids are composed of a hydrophilic head group and two hydrophobic tails. Each bare nanotube encompasses an ABA architecture, with a hydrophobic shaft (B) and two hydrophilic ends (A). To allow for regulated transport through the nanotube, we also introduce hydrophilic hairs at one end of the tube. The amphiphilic lipids are composed of a hydrophilic head group (A) and two hydrophobic tails (B). We select the dimensions of the nanotube architecture to minimize its hydrophobic mismatch with the lipid bilayer. We find the amphiphilic lipids and functionalized nanotubes to self-assemble into a stable hybrid vesicle or a bicelle in the presence of a hydrophilic solvent. We demonstrate that the morphology of the self-assembled functionalized nanotube-lipid hybrid structures is controlled by the rigidity of the lipid molecules and concentration of the nanotubes.

Phase separating binary fluids with the addition of immobile particles, which act as osmotic force centres, were simulated using a Lattice Boltzmann model in two dimensions. In the hydrodynamic over-damped limit, where the flow is entirely driven by capillary effects, the presence of particles that are preferentially wetted by one of the fluid components significantly affects the kinetics of the growth of the fluid domains. The late time dynamics is governed by the wetting interactions and the final size of the domains can be tailored by varying the strength of the particles-fluid interaction as well as the particles concentration. These features are predicted within a simple theoretical model and are amenable of experimental checks.