Dialkyldithiophosphates

Lubricants, Fuels, and Petroleum. The adipate and azelate diesters of through alcohols, as weU as those of tridecyl alcohol, are used as synthetic lubricants, hydrauHc fluids, and brake fluids. Phosphate esters are utilized as industrial and aviation functional fluids and to a smaH extent as additives in other lubricants. A number of alcohols, particularly the Cg materials, are employed to produce zinc dialkyldithiophosphates as lubricant antiwear additives. A smaH amount is used to make viscosity index improvers for lubricating oils. 2-Ethylhexyl nitrate [24247-96-7] serves as a cetane improver for diesel fuels and hexanol is used as an additive to fuel oil or other fuels (57). Various enhanced oil recovery processes utilize formulations containing hexanol or heptanol to displace oil from underground reservoirs (58) the alcohols and derivatives are also used as defoamers in oil production. 

Some commercially important isobutyl derivatives include isobutyl acetate, employed as a replacement solvent for -butyl acetate zinc dialkyldithiophosphate (ZDPP) lube oil additives isobutyl acrylate [106-62-8] and methacrylate [97-86-9] monomers isobutylamines and amino resins (qv). 

Ethers, esters, amides and imidazolidines containing an epithio group are said to be effective in enhancing the antiwear and extreme pressure peiformance of lubricants. Other uses of thiiranes are as follows fuel gas odorant (2-methylthiirane), improvement of antistatic and wetting properties of fibers and films [poly(ethyleneglycol) ethers of 2-hydroxymethyl thiirane], inhibition of alkene metathesis (2-methylthiirane), stabilizers for poly(thiirane) (halogen adducts of thiiranes), enhancement of respiration of tobacco leaves (thiirane), tobacco additives to reduce nicotine and to reduce phenol levels in smoke [2-(methoxymethyl)thiirane], stabilizers for trichloroethylene and 1,1,1-trichloroethane (2-methylthiirane, 2-hydroxymethylthiirane) and stabilizers for organic compounds (0,0-dialkyldithiophosphate esters of 2-mercaptomethylthiirane). The product of the reaction of aniline with thiirane is reported to be useful in the flotation of zinc sulfide. 

In the area of process monitoring TLC has been used for the study of the thermal decomposition of zinc di-isopropyl dithiophosphate (antiwear additive in lubricating oils) [458]. TLC analysis has been reported as a quality control tool for analysis of dispersing agents (alkylsalicylates, thioalkylphenolates), AOs (dithiophosphates, dialkyldithiophosphates) and their intermediates in lubricating oil (UV detection,... 

Eleven zinc dialkyldithiophosphates (ZDDPs) in lubricating oil additives were separated by NPLC [723] eight ZDDPs were separated on an ODS column... 

Zinc dialkyldithiophosphates (ZDDPs), which act as antiwear additives in lubricating oils and were postulated to exist in various molecular forms (monomer, dimer or neutral form, and basic form), were studied by multi-edge (Zn K-, P K- and S K-) XAS for structural assessment [311]. Grazing incidence absorption spectroscopy measurements have provided evidence for breakdown of the ZDDP molecule following its adsorption on to a steel substrate surface [312]. XANES and CEMS were used to study the interaction of per-fluoropolyalkyl ether (PFPAE) additives with Fe-based alloys [313],... 

A number of dialkyldithiophosphate zinc complexes were prepared and characterized in liquid and solid states, and as surface complexes on sphalerite. 31P NMR was used to characterize the coordination modes, whether terminal chelating or bridging between two metal centers. Correlations were made between data for the structurally characterized O.O -dicyclohexyldithiophos-phate zinc and the NMR of the surface complexes demonstrating bridging coordination between two neighboring zinc atoms on the synthetic sphalerite.568... 

The development and optimisation is described of a new curing system to replace lead-based compounds used in epichlorohydrin elastomers currently used in automotive applications. The system is based on 2,4,6-trimercapto-1,3,5-triazine and dialkyldithiophosphate, which is shown to produce a scorch-safe curing system and which confers excellent physical and ageing properties on epichlorohydrin rubbers. Trials are conducted in formulations for multilayer fuel hoses. 9 refs. 

Reactive FFs can only be applied to a few specific cases for which they have been developed, such as the hydrocarbon systems discussed in the first part of this section. For other systems, describing tribochemical reactions requires the use of quantum chemical methods. In recent studies, such methods have been applied to investigate the behavior of zinc phosphates (ZPs) in response to high pressures. ZPs form the basis of anti-wear films derived from zinc dialkyldithiophosphates (ZDDPs), which are additives that have... 

Review of the Lubrication of Metallic Surfaces by Zinc Dialkyldithiophosphates. 

Finally, a remark about nomenclature is in order. Throughout the literature the terms 0,0-dialkyldithiophosphate, 0,0 -dialkyldithiophosphate,... 

Inhibition of Oxidation. Several antioxidants were tested in chloroprene at 45°C. Those which can be classified as mainly suppressors of initiation (I), because of their ability to destroy hydroperoxides—namely, zinc dialkyldithiophosphates, zince dialkyldithiocarbamates, triphenyl-phosphine, and the like—had no inhibiting effect at the 100-p.p.m. level. 

Zinc Dialkyldithiophosphate Zinc Chloride Zinc Chromate Zinc Chromate Zinc Acetate... 

Most lubricating oils for engine use contain additives designed to improve such properties as lubricity, detergency, oxidation resistance, and viscosity. The additives contain elements that could be potentially harmful to catalysts. Table I lists these elements and their typical concentration in lubrication oils of 1973. The first three elements are combined usually in one compound, zinc dialkyldithiophosphate. Thus, before combustion, sulfur and phosphorus in oil are in a different chemical state than the same elements are in fuel. Little is known whether combustion nullifies these differences partially or fully. Some data, to be discussed subsequently, are available on the separate poisoning effects of these elements as derived either from the fuel or from the oil. 

Most commercial engine oils contain the antiwear agent zinc dialkyldithiophosphate (ZDP). The effect of phosphorus derived from oil is of particular concern when the poison concentration in the fuel is very low. One should keep in mind that the ZDP additive contains within its own chemical formula a potential scavenger for phosphorus, i.e., zinc. Other potential scavengers which form stable phosphates, such as alkaline earth metals, are also present in the commercial oil additive package. ... 

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

Among the sulfur-containing chelating ligands used in the electrosynthesis, it is necessary to mention dialkyldithiocarbamates and dialkyldithiophosphates, on whose basis complexes of the types 796 and 797, respectively, were prepared [554,587,588] ... 

The rearrangement of zinc dialkyldithiophosphate initiated by a double alkyl group migration from oxygen atoms to sulfur atoms (Fuller et al., 1998 Jones and Coy, 1981 Varlot et al., 2000), is believed to be the result of the following reaction mechanism (equation 1.2) ... 

---