Synthesis and demulsification performance of a hyperbranched polymer with melamine as central core

A hyperbranched polymer (PMEL) was prepared using melamine as central core by a modified "one pot" method. The polymer was characterized by nuclear magnetic resonance spectroscopy (H-1 NMR and C-13 NMR), Fourier transform infrared microscopy (FTIR), Gel permeation chromatography (GPC) and thermogravimetric analysis (TGA). Effect of standing time, temperature and concentration of PMEL on the demulsification performance of a diesel-in-water emulsion was investigated in detail. The transmittance of aqueous phase reached 91.3% if 50 mg/L of PMEL was added into an O/W emulsion for 240 min at ambient temperature. The interfacial tensions (IFT), zeta potential and microscopic analysis were further measured to explore the possible demulsifying mechanism. The current work shows that PMEL has a great application prospect in the demulsification of oil-water emulsion.