Lubrication additives

The development of a line of lubricant additives is an expensive and slow undertaking the market for these products —on the order of 10 billion dollars in 1992— is very large and is dominated by a few companies. 

The increase in the oil-change interval has already been a strong incentive for improving lubricant formulations. The increase in engine operating temperatures and the development of catalytic converters are without doubt two orientations that will have consequences on lubricant additives. 

Satriana, M.J. (1982), Synthetic oils and lubricant additives (advances since 1970) . Chemical Technology Review No. 207, Noyes Data Corporation, Park Ridge, NJ. 

Lubricant additives Lubricant-film bearings Lubricants... 

Triaryl phosphates are also used on a large scale as flame-retardant hydrauhc fluids (qv), lubricants, and lubricant additives (see Lubrications and lubricants). Smaller amounts are used as nonflammable dispersing media for peroxide catalysts. 

Poly(alkylene glycol)s are also used as lubricity additives ia water-based synthetic cutting and grinding fluids (36), and ia aqueous metalworking fluids. Under the high frictional heating at the tool or die contact with the workpiece, the polyalkylene glycol comes out of solution ia fine droplets which coat the hot metal surfaces. 

Much confusion exists as to the best choice of lubricant additives for a given situation. Evaluation both in the laboratory and in the field is difficult because of the dynamic nature of the drilling fluid and the wide range of factors that influence drill string torque and drag. Liquid lubricants are used at concentrations of 0.25—4 vol %, soHd materials at ca 6—29 kg/m (2—10 Ib/bbl). 

The remaining 15% of the elemental P is used in P -dependent apphcations which require the element as a direct reactant. The principal products include P2S5, PCl and POCl, 2 5 hypophosphite, with much smaller amounts leading to PH, red P, phosphonates, and various other phosphoms derivatives. Pinal apphcations include flame retardants (qv), lubricant additives, insecticides, herbicides, water treatment, cleaning compounds, plastici2ers, and semiconductors (14). 

Trichloromethanesulfenyl chloride has also been used for the preparation of lubricant additives (see Lubrication and lubricants). Some higher homologues and analogues of trichloromethanesulfenyl chloride have been reported, ie, trichlorovinylsulfenyl chloride [19411-15-5] 1,1,2,2-tetrachloroethanesulfenyl chloride [1185-09-7] 1,2,2,2-tetrachloroethanesulfenyl chloride [920-62-7] and pentachloroethanesulfenyl chloride [5940-94-3] (70—74). A commercial fungicide, Captafol [2425-06-17, is the reaction product of 1,1,2,2-tetrachloroethanesulfenyl chloride with tetrahydrophthalimide (75). 

Sulfurized olefins (S2CI2 plus isobutene) are further reacted with S and Na2S to give products useful as extreme pressure lubricant additives (144,145). The reaction of unsaturated natural oils with sulfur monochloride gives resinous products known as Factice, which are useful as art-gum erasers and mbber additives (146,147). The addition reaction of sulfur monochloride with unsaturated polymers, eg, natural mbber, produces cross-links and thus serves as a means for vulcanizing mbber at moderate temperatures. The photochemical cross-linking of polyethylene has also been reported (148). 

The principal commercial uses of sulfur monochloride are in the manufacture of lubricant additives and vulcanising agents for mbber (147,154,155) (see Lubrication AND lubricants Rubber chemicals). The preparation of additives for wear and load-bearing improvement of lubricating oils is generally carried out in two steps and the technology is described in numerous patents (155) (see Sulfurization and sulfchlorination). 

The mechanisms for the reaction of sulfur with alkanes and unsaturated compounds are highly speculative, being strongly influenced by the specific stmcture of the substrate and by the conditions (particularly temperature) of reaction. Alkane (4), olefin (5), animal fat (6), and vegetable oil (7) sulfurization have been extensively studied because these reactions are models for vulcanization. Moreover, the products are used as lubricant additives. 

Sulfuiized and sulfurchlorinated unsaturated compounds and meicaptans are used as lubricant additives (antiwear, friction modification, load-carrying, extreme pressure and temperature, corrosion inhibition, and antioxidants), refinery catalyst regeneration compounds, steel processing (annealing) aids, and vulcanization catalysts (see Lubrication and lubricants). 

The by-products of these reactions are sulfides. The sulfide formed in the synthesis of 2-mercaptoethanol, 3-thia-l,5-pentanediol (thiodiglycol), has a variety of uses ranging from lubricant additive intermediates to textile finishing. 

Various appHcations such as lubricant additives, dyes, pigments, and catalysts are under investigation. Tungsten can be deposited from tungsten hexacarbonyl, but carbide formation and gas-phase nucleation present serious problems (1,2). As a result, tungsten halides are the preferred starting material. 

Prior to 1975, benzene was catalytically oxidized to produce maleic anhydride, an intermediate in synthesis of polyester resins, lubricant additives, and agricultural chemicals. By 1986 all commercial maleic anhydride was derived from oxidation of / -butane. It is expected that / -butane will remain the feedstock of choice for both economic and environmental reasons. 

Hydraulic Fluids and Lubricants. The use of borate esters in hydrauHc fluids (qv) and lubricants (see Lubrication and lubricants) has been described in numerous patents (40,43,44). A variety of borate esters have been described that can be used as multiflinctional lubricant additives having antiwear and antifriction properties (45). 

Lubrication Additive. Cerium fluoride, CeF, can be used as an additive to lubricant formulations to improve extreme pressure and antiwear behavior (43). The white soHd has a crystal stmcture that can be pictured as [CeF] layers separated by [F] atom sheets, a layer stmcture analogous to that of M0S2, a material that CeF resembles in properties. 

J. M. Dumdum and co-workers, "Lubricant Grade Cerium Fluoride A New SoHd Lubricant Additive for Greases, Pastes and Suspensions, paper presented Annual Meeting National Lubrication Grease Institute, Oct. 23—26, 1983, Kansas City, Mo. 

Ranney, M. W., Lubricant Additives, Noyes Data Corporation, New Jersey (1978)... 

Reduced Wear Electrical Conductivity Glass fibers Carbon fibers Lubricating additives Carbon fibers Carbon powders Ductility, cost Tensile strength, ductility, cost Ductility, cost Tensile strength, ductility, cost... 

RT-ILs are also selected as lubricant additives. Usage of ionic liquids as boundary lubricant additives for water has resulted in dramatically reduced running-in periods for silicon nitride materials [70]. When ILs were mixed into a neat mineral oil, the mixture has proven to produce lower wear on aluminum flat than either the oil or the ionic liquid alone [72], which indicates that a small amount of ILs in the mineral oil may function as an anti-wear additive. 

Similar results were reported by other investigators, [19,20], but attention was paid to investigating the effect of lubricant additives on the boundary film thickness. It is speculated that there should be no adsorbed layers formed on rubbing surfaces if purified and nonpolar lubricants are applied. The interferometer measurements show that in the case of using base oils, the relation between the film thickness and rolling speed follows the EHL power law pretty well down to 1 nm (Fig. 6(a)), or sometimes the film thickness may deviate from the Hamrock and Dowson s line and turn down quickly (Fig. 6(b)). If there is a small percentage of additives in the lubricant, on the other hand, the deviation from the power law occurs in a different way that the h-V... 

Luo and Pan [108,109], using a slurry with Si02 particles about 12 nm in diameter, improved lubricant additives, and a pH value of about 1.5, have got ten a much lower surface roughness and waviness measured by both Chapman MP2000+ and AFM (Fig. 40). 

Phosphatides or phospholipids are environmentally safe lubricating additives [678]. 

B. A. Andreson, R. G. Abdrakhmanov, G. P. Bochkarev, V. N. Umutbaev, V. V. Fryazinov, V. N. Kudinov, and F. M. Valiakhmetov. Lubricating additive for water-based drilling solutions—contains products of condensation of monoethanolamine and tall oils, kerosene, monoethanolamine and flotation reagent. Patent SU 1749226-A,... 

Z. Fang, S. Peterson, and R. Denton. O-ring seal with lubricant additives for rock bit bearings. Patent GB 2318139, 1998. 

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