Variable reactivity and phase separation in patchy particle systems

ABSTRACT

Using statistical model, we study mechanisms of phase separation in a solution consisting of patchy particles, which are capable to form directed and saturated thermoreversible bonds. We focus on the impact of variable reactivity of patchy particles on the form of miscibility gap. We show that the variation of model parameters determining features of interparticle interaction makes it possible to obtain miscibility gaps of different types within the unified formalism. In particular, we uncover two different mechanisms of the formation of phase separation curves with lower critical solution temperature. The first mechanism is realised in the case of positive bonding energy; the second one can takes place when the energy of formation of two-bonded particles is lower than that for all other m-bonded ones. We conclude that the most interesting and non-trivial phase behavior is observed in the case of patchy particles with variable reactivity. Using rigorous statistical model, we uncover new mechanisms of phase separation in a solution consisting of patchy particles, which are capable to form directed and saturated thermoreversible bonds. This topic corresponds to state of the art in modern chemical physics. The results obtained shed light on interplay between features of non-isotropic interactions and phase behavior in both molecular and nanoparticle systems. We conclude that the most interesting and non-trivial phase behavior is observed in the case of patchy particles with variable reactivity.

GRAPHICAL ABSTRACT

KEYWORDS:

• Patchy particles
• non-isotropic interaction
• miscibility gap
• lower critical solution temperature
• lattice-gas model

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

R. E. Ryltsev  http://orcid.org/0000-0003-1746-8200

Additional information

Funding

This work was carried out within the framework of government assignment of IMET UB RAS. The study of relation between structure and phase behaviour was supported by Russian Science Foundation [grant no.18-12-00438]. MV and RE were partially supported by Russian Foundation for Basic Research [grant no. 18-02-00643].