Molecular dynamics simulation and experimental study on the effect of surfactants on the compatibility of P(S-DVB)-SO4/CeO2 composite interface

Abstract

To improve the interfacial compatibility of core–shell composite abrasive composed of sulfate-modified divinylbenzene crosslinked polystyrene P(S-DVB)-SO₄) and CeO₂, cetyltrimethylammonium bromide (CTAB), sodium dodecylbenzene sulfonate (SDBS), and polyethylene glycol (PEG) were introduced. Using molecular dynamics simulation method, the adsorption configurations, adsorption energies, relative concentration distribution and radial distribution function (RDF) of three surfactants on P(S-DVB)-SO₄ and CeO₂ surfaces were analyzed, and it was found that CTAB has the best interfacial compatibility. The changes in atomic structure, relative concentration distribution, and binding energy of P(S-DVB)-SO₄/CeO₂(100) interface after adding CTAB were studied. The P(S-DVB)-SO₄/CeO₂ abrasive was prepared by the soap-free lotion polymerization. The TEM, HRTEM, nitrogen adsorption–desorption (BET), and atomic force microscopy (AFM) nanoindentation tests were conducted, and the influences of CTAB on the interface structure and strength were further verified through experiment. Finally, the effect mechanism of surfactants on the compatibility of P(S-DVB)-SO₄/CeO₂ interface was obtained.