Effects of Repulsion Parameter and Chain Length of Homopolymers on Interfacial Properties of An/Ax/2BxAx/2/Bm Blends: A DPD Simulation Study

We explored the effects of the repulsion parameter (aAB) and chain length (NHA or NHB) of homopolymers on the interfacial properties of An/Ax/2BxAx/2/Bm ternary polymeric blends using dissipative particle dynamics (DPD) simulations. Our simulations show that: (i) The ternary blends exhibit the significant segregation at the repulsion parameter (aAB = 40). (ii) Both the interfacial tension and the density of triblock copolymer at the center of the interface increase to a plateau with increasing the homopolymer chain length, which indicates that the triblock copolymers with shorter chain length exhibit better performance as the compatibilizers for stabilizing the blends. (iii) For the case of NHA = 4 (chain length of homopolymers An) and NHB (chain length of homopolymers Bm) ranging from 16 to 64, the blends exhibit larger interfacial widths with a weakened correlation between bead An and Bm of homopolymers, which indicates that the triblock copolymer compatibilizers (Ax/2BxAx/2) show better performance in reducing the interfacial tension. The effectiveness of triblock copolymer compatibilizers is, thus, controlled by the regulation of repulsion parameters and the homopolymer chain length. This work raises important considerations concerning the use of the triblock copolymer as compatibilizers in the immiscible homopolymer blend systems.

Thermoset resin curing simulation using quantum-chemical reaction path calculation and dissipative particle dynamics

Thermoset resin, which is commonly used as a matrix in carbon-fiber-reinforced plastic, requires curing procedures. We propose a curing simulation technique involving a dissipative particle dynamics (DPD) simulation, which can...

Controlling Evaporation Induced Self-Assembly of Polymeric Nanoparticles: A VOF-DPD Study

A mesoscopic simulation method combining multiphase Volume of Fluid (VOF) method and Dissipative Particle Dynamics (DPD) is employed to investigate and control self-assembly of charged polymeric nanoparticles in microdroplet solution deposited on plane substrate during solvent evaporation. A droplet evaporation model is first developed and validated. A coupling scheme between the CFD and the DPD simulation for particles is then presented. The DPD simulation includes the DLVO forces between the particles, their interaction with the substrate surface, Stokes drag, Brownian, and capillary forces. Numerical results show qualitative agreement with available experimental results. The proposed simulation method is expected to provide valuable tools for controlling and optimizing self-assembly of nanoparticles.

Electrocoalescence of water in oil emulsions: a DPD simulation study and a novel application of electroporation theory

Electrocoalescence of water in oil emulsions can be described by electroporation theory and predictions compared well to DPD molecular simulations.