Dissipative particle dynamics study on the phase morphologies of the ultrahigh molecular weight polyethylene/polypropylene/poly(ethylene glycol) blends

The dissipative particle dynamics (DPD) simulation method has been used to study mesophase formation of the binary UHMWPE/PP and ternary UHMWPE/PP/PEG blends. The effects of shear rates and volume fractions of each of the blend components on end-to-end distances of UHMWPE, diffusivities and mesoscale morphologies of the blends have been investigated in detail. As compositions of the UHMWPE/PP and UHMWPE/PP/PEG blends vary, the mesoscale simulations have predicted the ordered structures with defined morphologies of lamellas, perforated lamellas, hexagonal spheres, and body-centered-cubic spheres. Micelle-like melted structures between totally disordered and the ordered phases have also been found in the UHMWPE/PP (10/90) blends. Immiscibility property of UHMWPE, PP and PEG induces the phase separation and exhibits different mesoscpic morphologies at different shear rates and volume fractions. Taking the shear rates dependence of mesophase into account, the change in morphology of the UHMWPE/PP/PEG blends with shear rate is also well studied in this work. As a function of PP concentration, the end-to-end distances of UHMWPE are found to decrease with the increase of PP concentration. This effect is more prominent for a high amount of PP.