Lubricants 

About: Lubricants is an academic journal published by Multidisciplinary Digital Publishing Institute. The journal publishes majorly in the area(s): Materials science & Lubrication. It has an ISSN identifier of 2075-4442. It is also open access. Over the lifetime, 1224 publications have been published receiving 9752 citations.

A Review of Ionic Liquid Lubricants

Abstract: Due to ever increasing demands on lubricants, such as increased service intervals, reduced volumes and reduced emissions, there is a need to develop new lubricants and improved wear additives. Ionic liquids (ILs) are room temperature molten salts that have recently been shown to offer many advantages in this area. The application of ILs as lubricants in a diverse range of systems has found that these materials can show remarkable protection against wear and significantly reduce friction in the neat state. Recently, some researchers have shown that a small family of ILs can also be incorporated into non-polar base oils, replacing traditional anti-wear additives, with excellent performance of the neat IL being maintained. ILs consist of large asymmetrical ions that may readily adsorb onto a metal surface and produce a thin, protective film under boundary lubrication conditions. Under extreme pressure conditions, certain IL compounds can also react to form a protective tribofilm, in particular when fluorine, phosphorus or boron atoms are present in the constituent ions.

Solid Lubrication with MoS2: A Review

Abstract: Molybdenum disulfide (MoS2) is one of the most broadly utilized solid lubricants with a wide range of applications, including but not limited to those in the aerospace/space industry. Here we present a focused review of solid lubrication with MoS2 by highlighting its structure, synthesis, applications and the fundamental mechanisms underlying its lubricative properties, together with a discussion of their environmental and temperature dependence. The review also includes an extensive overview of the structure and tribological properties of doped MoS2, followed by a discussion of potential future research directions.

Lubricants in Pharmaceutical Solid Dosage Forms

Abstract: Lubrication plays a key role in successful manufacturing of pharmaceutical solid dosage forms; lubricants are essential ingredients in robust formulations to achieve this. Although many failures in pharmaceutical manufacturing operations are caused by issues related to lubrication, in general, lubricants do not gain adequate attention in the development of pharmaceutical formulations. In this paper, the fundamental background on lubrication is introduced, in which the relationships between lubrication and friction/adhesion forces are discussed. Then, the application of lubrication in the development of pharmaceutical products and manufacturing processes is discussed with an emphasis on magnesium stearate. In particular, the effect of its hydration state (anhydrate, monohydrate, dihydrate, and trihydrate) and its powder characteristics on lubrication efficiency, as well as product and process performance is summarized. In addition, the impact of lubrication on the dynamics of compaction/compression processes and on the mechanical properties of compacts/tablets is presented. Furthermore, the online monitoring of magnesium stearate in a blending process is briefly mentioned. Finally, the chemical compatibility of active pharmaceutical ingredient (API) with magnesium stearate and its reactive impurities is reviewed with examples from the literature illustrating the various reaction mechanisms involved.

Chemically Modifying Vegetable Oils to Prepare Green Lubricants

Abstract: Chemically modifying vegetable oils to produce an alternative to petroleum-based materials is one of the most important emerging industrial research areas today because of the adverse effects of petroleum products on the environment and the shortage of petroleum resources. Biolubricants, bioplasticizers, non-isocyanate polyurethanes, biofuel, coating materials, biocomposites, and other value-added chemicals can easily be produced by chemically modifying vegetable oils. This short review discusses using vegetable oils or their derivatives to prepare lubricants that are environmentally safe. Chemically modified vegetable oils are generally used as base fluids to formulate environmentally friendly lubricants. Reports of their application as sustainable additives have attracted special attention recently because of their enhanced multifunctional performances (single additives perform several functions, i.e., viscosity index improver, pour point depressant, antiwear products) and biodegradability compared with commercial additives. Here, we have reviewed the use of chemically modified vegetable oils as base fluids and additives to prepare a cost-effective and environmentally friendly lubricant composition.

The Preparation of Graphene Oxide and Its Derivatives and Their Application in Bio-Tribological Systems

Abstract: Graphene oxide (GO) can be readily modified for particular applications due to the existence of abundant oxygen-containing functional groups. Graphene oxide-based materials (GOBMs), which are biocompatible and hydrophilic, have wide potential applications in biomedical engineering and biotechnology. In this review, the preparation and characterization of GO and its derivatives are discussed at first. Subsequently, the biocompatibility and tribological behavior of GOBMs are reviewed. Finally, the applications of GOBMs as lubricants in bio-tribological systems are discussed in detail.