Synthesis and Characterization of Polystyrene-Montmorillonite Nanocomposite Particles Using an Anionic-Surfactant-Modified Clay and Their Friction Performance

Abstract

Polystyrene-organo-montmorillonite (PS-OMMT) nanocomposite particles were prepared via emulsion polymerization of styrene in the presence of montmorillonite modified with an anionic surfactant, sodium lauryl sulfonate (SLS), and its tribological properties as an additive to polyalphaolefin (PAO) were tested. The results of Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) showed that SLS molecules resided in the montmorillonite (MMT) interlayer space. The effects of OMMT on the morphology and properties of the nanocomposites were also investigated. Gel permeation chromatography (GPC) and dynamic light scattering (DLS) demonstrate that the presence of OMMT can effectively reduce the average molecular weight and average particle size of PS. XRD and transmission electron microscopy (TEM) of the PS-OMMT nanocomposites indicate that exfoliated and intercalated structures form and that the MMT layers either are partly embedded inside the PS particles or remain on their surface. Compared with pure PS, the PS-OMMT nanocomposites possessed higher stability to thermal decomposition and higher glass transition temperatures. Adding nanocomposite particles reduces the friction coefficient, and thus, the antiwear properties of the PAO are significantly improved. The PS-OMMT-3 (3 wt % of OMMT based on styrene) particles have the best tribological performance and maintained a stable, very low coefficient of friction of 0.09.

Effect of Bifunctional Montmorillonite on the Thermal and Tribological Properties of Polystyrene/Montmorillonite Nanocomposites

“…In addition, the peak at 1725.7 cm −1 was due to the C=O stretching vibration of methacrylic acid. These observations indicate that the polymerization reaction of styrene monomer has been occurred [34]. The FTIR spectra of PS/P-MMT not only had the characteristic bands of PS, but also exhibited new absorption bands at 1039.7 cm −1 , which were assigned to Si-O stretching vibrations of the MMT.…”

Synergistic Effect of Hybridized Cellulose Nanocrystals and Organically Modified Montmorillonite on κ-Carrageenan Bionanocomposites

“…XRD patterns showed that intercalation occurred, with a diffraction peak shift to a lower angle, accompanied by broadening and intensity decrease in the diffraction peak. This indicated a disordered intercalated/exfoliated structure [ 5 , 24 , 30 , 31 ].…”

Special Issue on “Nanotech for Oil and Gas”

“…They demonstrated that the graphene nanoplatelet and the silver NPs increased the plastic viscosity by up to 89.2% and 64.2%, respectively, while both the yield point and the fluid loss values were reduced. The paper by C. Yu et al [5] reported polystyrene-organo-montmorillonite (PS-OMMT) nanocomposite particles modified with an anionic surfactant, and its tribological properties as an additive to polyalphaolefin (PAO). They showed that the presence of OMMT can effectively reduce the average molecular weight and particle size of PS.…”