A new ball milling method to produce organo-montmorillonite from anionic and nonionic surfactants

• New organo-montmorillonites were prepared by ball milling.
• Their thermal stabilities were better than that of cationic-organo-montmorillonite.
• The first d-spacings exceeded 5.0 nm.
• The preparation process was water-free, simple, environmentally friendly.
• Dual mechanisms of intercalation and stacking were proposed.

BackgroundOrgano-montmorillonite (OMt) is widely used in oil well drilling fluids, paint, grease, cosmetics, and personal care products. Nanocomposites which are prepared using organoclays and polymers. Generally, organo-montmorillonite can be prepared using ion-exchange reactions with cationic surfactants. However, cationic-organo-montmorillonite (COMt) has poorer thermal stability. In addition, the preparation process of traditional OMt uses a large amount of water. The process would emit a large amount of effluent and increase cost.ObjectiveThe aim of this work is to prepare nonionic-organo-montmorillonite (NOMt) and anionic-nonionic-organo-montmorillonite (ANOMt) using ball milling method. And NOMt and ANOMt are of better thermal stability than COMt.MethodOrgano-montmorillonite was prepared using ball milling method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), Thermogravimetric (TG) analysis, differential thermal analysis (DTA) and contact angle test.ResultsXRD analysis indicated that the interlayer spacing of Ca2+-montmorillonite (Ca-Mt) was expanded. ANOMt showed a large d-spacing above 5.0 nm. SEM analysis demonstrated that the ANOMt was flaky in substance. FT-IR spectra proved that the chemical environment of the surfactants changed. TG and DTA results showed that the thermal stabilities of NOMt and ANOMt were better than that of COMt. FT-IR and thermal analysis indicated that the interlayer water was replaced. The contact angle tests of the samples indicated that NOMt and ANOMt were of oleophilic property.ConclusionCa-Mt was modified with nonionic surfactant and anionic surfactant by ball milling method, without any added water. NOMt and ANOMt were prepared. The thermal stabilities of NOMt and ANOMt are better than COMt. Dual mechanisms of intercalation and stacking were proposed.