Stepwise study on Janus-like particles fabricated by polymeric mixtures within soft droplets: a Monte Carlo simulation

Abstract

Using Monte Carlo simulations, a stepwise study (from simple to complex) is followed to investigate Janus particles self-assembled from polymer mixtures within soft droplets. When the polymer mixtures are changed from a homopolymer/homopolymer (A/D) mixture to a diblock copolymer/homopolymer (AB/D) mixture and then to a triblock copolymer/homopolymer (ABC/D) mixture, the self-assembled structures transform from classic Janus particles to hierarchical Janus structures with novel hemi-domains. The effects of the incompatibility between two components, polymer–solvent interactions and the ratio of two components of the mixture on the Janus structure are systematically examined. It is found that the Janus structure is highly related to the incompatibility between two components of the mixture, while the sizes of the two hemispheres in a Janus particle can be well tuned by adjusting the ratio of the components in the mixture. Moreover, the corresponding incompatibility between two components of the mixture for the transformation point is increased when the mixture is changed from the A/D to the AB/D and then to the ABC/D mixture. More interestingly, it is found that the variation of the aggregation degree of the changed component with time gradually lags behind that of the homopolymer component (D) during the formation of Janus particles when the component in the mixture changes from A to AB and then to ABC. The simulation result could provide theoretical guidance for the preparation of designable Janus particles.