Ashless additives dispersants

Lubricant formulations meeting API CG-4 standard and above have generally contained greater than 0.1% levels of phosphorus. Eurthermore, as the soot levels in lubricants have increased so have the levels of ashless dispersants, typically exceeding 6%. It is believed that the additional dispersant helps to minimise wear by dispersing soot and contributing to the oil film thickness. Lubricants with lower... 

Ashless additive development has reduced the risk of solid deposit formation and ashless dispersants, anti-oxidants and anti-foam agents are now permitted in most engines. Non-dispersant mineral oils are now used primarily for older aircraft and as a running-in oil for new engines or after overhaul. 

Co-oligomers of 1-alkenes (C4-C32) and derivatives of acrylic acids are additives to lubricating oils that are useful as low-temperature and ashless sludge dispersants and detergents [79]. 

Lubricant additives (Ashless dispersant A and B, Zinc dialkyldithiophosphate) TT A (Ward et ah, 2002b)... 

Mixtures of metallic detergents, such as phenates, sulfonates, phosphonates, and salicylates with ashless dispersants such as succinimides and benzylamine, together with zinc dialkyldithiophosphate (ZDDP), can lead to new effects. The possible interactions between these main additives used in lubricating formulations when dissolved/dispersed in hydrocarbon media are shown in Fig. 2.8 together with an indication of the intensity of those respective interactions. 

Detergent-dispersant interactions at surfaces. In 4-ball wear tests, an ashless dispersant was found to have an adverse effect on ZDDP-sulfonate-carbonate hardcore RM additives. A high molecular weight Schiff base had the worst effect, followed by a bis-PIBS m-PIBS had the least adverse effect. Interactions among additives affects valve train wear. One of the effects is that a succinimide together with other additives increases the decomposition temperature of ZDDP (Ramakamur, 1994 Shirahama and Hirata, 1989). 

The typical detergent-dispersant additives used in modem lubricating oils are metallic detergents/sulfonates, phenolates, phosphonates, salicylates, ashless dispersants/succinimides and benzylamines. Water is solubilized by strong ion-dipole interactions. The solubilization of water (Watanabe, 1970) by hydrogen bond formation with succinimides and the amount solubilized is smaller than that solubilized by sulfonates. 

Additive containing no metallic elements, e.g., ashless dispersant succinimides, succinate esters. 

Use In lubricating-oil additives for ashless dispersant processing, rolling, and compressor oils caulks, sealants, adhesives as an elastomeric process aid and cling improver in cling films. 

Modern oil formulations now contain high levels of ashless dispersants to keep the soot particles well dispersed. Antiwear additives, mainly ZDDP, have also been boosted to cope with the higher levels of abrasive soot wear. 

Though ashless dispersants made by Mannich condensation reaction, functionalized ethylene-propylene dispersants, and succinate ester dispersants can be used in ATF formulations, succin-imide dispersants are more commonly nsed. The dispersants used in ATFs have similar chanistries as those described in engine oil applications, except in most cases the molecular weights of the polyisobutyl hydrocarbon chain of the dispersants used in ATFs are lower. Furthermore, the dispersant molecules are reacted with boric acid and caped with additional antiwear chemistries. 

Industrial lubricants include metalworking lubricants, industrial greases, industrial lubricants, transformer oils, hydraulic oils, refrigeration oils, turbine oils, compressor oils, rock drill lubricants, paper machine oils, way lubricants, and railway journal box oils. The required additive package for each of these industrial oils is different depending on its specific application. Unlike lubricants used in automotive lubrication, industrial lubricants typically do not use metallic detergents and ashless dispersants as additives to keep metal surfaces clean and prevent insoluble materials from formation of deposits on metal surfaces [23]. However, in recent years the use of overbased detergents to supplement performance of the antiwear additive zinc dialkyl dithiophosphate has been reported [24]. 

Lube oil additives have increased in importance since better engine performances are required to meet air pollution standards and increased fuel efficiency. End reaction products of MA with olefins, e.g., polyisobutylenesuc-cinic anhydride, other alkenylsuccinic anhydrides, etc. are used as viscosity index improvers and also as ashless dispersants in the fuels. (See Chapter 5.)... 

Vinyl acetate terpolymers prepared with lauryl fumarate are claimed useful as ashless detergency additives, viscosity index improvers, dispersants, etc., for lubricating and additives to improve jet fuel... 

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