Solid lubricant, definition

Tests showed that liquid lubricants do not even provide adequate lubrication in the lower Vacuums of space simulators. Solid lubricants, such as molybdenum disulfide, tungsten disulfide. and the soft metals have given better results. However, the known data about space lubricants are results of simulator measurements made in the pressure range of 10 s to 1C6 torr which does not simulate real space conditions, and therefore, these available data cannot be considered completely valid. It can be expected that definite data on lubricant performance in a vacuum will be obtained by conducting tests in a simulator that reaches the low 10"10 torr range. At this press level, the monolayer formation time is increased to at least several hours which will result in a sufficient time span for observing the metal... 

Wettability of a solid surface definition and assessment The concept of wettability of a solid by a liquid is directly related to the wetting processes. This concept is specially useful in the fields of detergency, lubrication or enhanced oil recovery. In the context of the oil industry, proposals were made by Briant and Cuiec (1972) for the experimental assessment of wettability, which was defined in terms of the thermodynamic affinity of a solid surface for a liquid. 

The definition of different lubrication regimes is a historic problem [41 ]. In boundary lubrication, molecules will be absorbed on a solid surface of a tribo-pair and form a monomo-lecular absorbed layer as described by Hardy [42] as shown in Fig. 1 (a). If the film thickness of lubricants in the contact region is from a few nanometres to tens of nanometres, different layers will be formed as shown in Fig. 1 (b) proposed by Luo et al. [3,4]. The layer close to the surfaces is the adsorbed film that is a monomolecular layer. The layer in the... 

Thus each solid face makes a definite quantitative contribution to the friction, irrespective of what the other solid face may be, or what lubricant is present. At one time Hardy attempted to explain this on the theory that the influence of the attraction of the solid face extended for long distances, but more recent analysis of the occurrences during sliding indicates that the process is very complex, and that the coefficient of friction is not, as a rule, a quantity capable of simple interpretation in terms of the properties of continuous surface films, and of the underlying solid. 

Table 40 lists the most frequently reported chemical features of Mannich bases employed as surfactants, along with brief indications of their individual function, although this aspect is hardly specifiable, as several different practical definitions can be given for the same molecule. For example, an antioxidant for lubricating oil may be also named an antisludge compound, due to its capability to reduce the formation of solid precipitate caused by oxidation processes. 

In its strictest definitive form, an ointment is classified as any semi-solid containing fatty material and intended for external application (U.S. Pharmocopeia, USP). In this discussion, ointments will be defined as semisolid anhydrous external preparations. In the nineteenth century, ointments were based on lard, a compounding material, the usefulness of which was severely limited by its tendency to turn rancid. Early in the twentieth century, lard was replaced by petrolatum (white or yellow soft paraffin or petroleum jelly). In present practice, nonmedicated ointments (ointment bases) are used alone, for emollient or lubricating purposes, or in combination with a drug for therapeutic purposes. 

Lubrication is a process of reducing friction and/or wear (or other forms of surface damage) between relatively moving surfaces by the application of a solid, liquid, or gaseous substance (i.e., a lubricant). Since friction and wear do not necessarily correlate with each other, the use of the word and in place of and/or in the above definition is a common mistake to be avoided. The primary function of a lubricant is to reduce friction or wear or both between moving surfaces in contact with each other. 

Definition Mixt. of resin acids and varies somewhat with source Properties Yel. or brn. solid soften, pt. (R B) 80 C acid no. 163 Uses Binder in rust-preventive coatings mfg. of paints lubricant for oil-well drilling muds plasticizer for rubber prod, of abietic acid, calcium rosinate, maleic and phenolic resins, polymerized rosin, rosin ester gum, sodium rosinate, zinc rosinate emulsifier for polymerization of syn. rubbers component of food-contact articles in food-pkg. adhesives in food-contact coatings Regulatory FDA 21 CFR 175.105,175.300,178.3870 Manuf./Distrib. Arakawa Chem. Ind. Arizona Chemical Georgia-Pacific Resins Hercules Int l. Paper Matteson-Ridolfi Rekhhold See a/so Rosin... 

CAS 68308-22-5 EINECS/ELINCS 269-637-1 Synonyms Fatty acids, montan-wax, calcium salts Montan acid, calcium salt Definition Calcium salt of the acids derived from montan acid wax Properties Solid m.p. 1223 C Uses Lubricant for PVC anticaking agent in cosmetics... 

Definition Ester of cetyl alcohol and stearic acid Empirical C34H68O2 Formula CH3(CH2)i6COO(CH2)i5CH3 Properties Wh. solid m.w. 508.91 m.p. 56 C Uses Emollient, lubricant for cosmetics conditioner, opacifier, gloss aid for hair care prods. antistat, processing lubricant for plastics plasticizer, lubricant in food-contact PS... 

Definition Natural fat obtained from fruit of the Karite tree, Butyrospermum parkii Properties Gray-wh. solid dens. 0.9175 iodine no. 53-65 sapon. no. 178-190 Uses Emollient, consistency agent, lubricant, moisturizer, vehicle, carrier, vise, modifier, skin protectant, fatting agent for lotions, pharmaceutical dermatologicals, suppositories, o/w and w/o creams and emulsions skin conditioner, occlusive agent, solvent for suntan preps., body lotions, soaps, shampoos... 

The term filler is very broad and encompasses a very wide range of materials. We arbitrarily define in this book as fillers a variety of natural or synthetic solid particulates (inorganic, organic) that may be irregular, acicular, fibrous or flakey and are used in most cases in reasonably large volume loadings in plastics, mostly thermoplastics. Continuous fibers or ribbons are not included. Elastomers are also not included in this definition as well as many specialty additives that are used at low concentrations (e.g. pigments, lubricants, catalysts, etc). 

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