Nylons lubrication

Uses Polymer modifier for epoxies and urethanes internal mold release agent for nylons lubricant, release agent, component in coatings for textiles and polishes Manuf/Distrib. ABCR Gelest Trade Names AMS-233... 

Uses Wetting and leveling agent for wool and nylon lubricant for textile industry Properties Gel EmkatolM [Emkay ]... 

In order for a plasticizer to enter a polymer stmcture the polymer should be highly amorphous. Crystalline nylon retains only a small quantity of plasticizer if it retains its crystallinity. Once it has penetrated the polymer the plasticizer fills free volume and provides polymer chain lubrication, increa sing rotation and movement. 

Over time, finish components tend to separate and migrate within the fiber and throughout the yam package. With nylon, the ionic emulsifiers and antistats tend toward the core of the fiber whereas the hydrocarbon lubricants remain on the surface. It is, therefore, essential to scour yams and fabrics at neutral to basic pH to reemulsify the lubricant and remove the finish emulsifier prior to dyeiag. In formulating any new finish, environmental issues such as biodegradabihty, water and air pollution must be considered (137). 

Additives and Modifications. For plastics uses, nylon is only rarely employed as the pure polymer, and is almost always modified to some extent even if only with the addition of a small amount of lubricant. There has been a dramatic increase in the range and number of combinations of additives used to modify nylons, resulting in a huge expansion in the number of commercial grades available and the uses to which they can be put. It is not unusual to find formulations that contain less than 50% nylon and half a do2en or more additives. 

Lubricants. Lubricants are used to improve the melt flow, screw feeding, and mold release of nylons. Long-chain acids, esters, and amides are used together with metal salts, eg, metal stearates. Improved melt flow is mainly a function of molecular weight reduction during mol ding. Mold release is improved by waxes of limited compatibiHty with nylon, which migrate to and lubricate the mold surface. 

Plastics. Almost all commercial plastics find some use both dry and lubricated for sliding at low speeds and light loads the most commonly used thermoplastics are nylon, acetal resins, and polytetrafluoroethylene (PTFE). Typical thermosetting resins for bearing appHcations are phenoHcs, polyesters, and polyimides. Table 8 compares the characteristics of plastic bearing materials with those of graphite, wood, and mbber which find use in somewhat similar appHcations. 

As an example in estimating wear rate in a nylon bushing consider a 10-rnm diameter shaft miming 900 rpm (0.47 m/s) under 0.5 x 10 N/m (70 psi) load. The P/ of 0.235 X 10 N/m -m/s(6510 psi-fpm) and if = 0.24 x 10 m /N for filled nylon in Table 9 gives a wear rate of 0.20 mm/1000 h. Since Pp test results vary widely, these wear estimates are only guides. For maximum utiHty, the test materials, finishes, temperature, load, speed, and lubrication should dupHcate as nearly as possible those in the planned appHcation. 

Many modifiers and additives have been described for use with nylon composites, but generally a small amount, 0.05—1 wt %, of a lubricity aid, such as sodium or 2inc stearate (4) is added to enhance both resin flow during processing and removal from the mold after consoHdation. 

Lubricity of crystalline polymers is usually higher than that of amorphous polymers. Excellent machinery parts are made from crystalline nylon-6,6 resins, eg, gears, cams, wedges, and other components not requiring lubrication. Gears made of amorphous polyimide resin, on the other hand, do not exhibit this feature. 

Laboratory tests and experience during use have demonstrated that the nylons have extremely good abrasion resistance. This may be further improved by addition of external lubricants and by processing under conditions which develop a highly crystalline hard surface e.g. by use of hot injection moulds and by annealing in a non-oxidising fluid at an elevated temperature (150-200°C for nylon 66). 

Table 18.3 Effect of lubricants on the kinetic coefficient of friction of nylon 66 (like surfaces) ...

Self-lubricating grades are of particular value in some gear and bearing applications. One commercial nylon compound incorporates 0.20% molybdenum disulphide and 1 % of graphite whilst many other commercial compounds contain only one of these two lubricants. 

There is persisting interest in nylon-RIM materials as alternatives to polyurethane-RIM. Advantages of the nylon materials are the better shelf life and lower viscosity of the reaction components, ability to mould thick-walled articles, absence of a need for mould lubrication and the ability to avoid using isocyanates with their associated hazards. The main disadvantages of nylon-RIM are the need to have heated storage tanks and elevated temperature reactions, difficulties in catalyst handling and the high water absorption of the product. Possible markets include exterior car body components and appliance and business machine components. 

There has been only one major use for ozone today in the field of chemical synthesis the ozonation of oleic acid to produce azelaic acid. Oleic acid is obtained from either tallow, a by-product of meat-packing plants, or from tall oil, a byproduct of making paper from wood. Oleic acid is dissolved in about half its weight of pelargonic acid and is ozonized continuously in a reactor with approximately 2 percent ozone in oxygen it is oxidized for several hours. The pelargonic and azelaic acids are recovered by vacuum distillation. The acids are then esterified to yield a plasticizer for vinyl compounds or for the production of lubricants. Azelaic acid is also a starting material in the production of a nylon type of polymer. 

DSM Engineering Plastics, nylon, PBT, Polycarbonate Thermoplastic Elastomer PC/ABS Conductive Resins Thermoplastics Reinforced and Filled Thermoplastics Lubricated... 

Cyclooctadiene is reacted with bromine to make fire-retardants. Cyclododecane is oxidized with air and then nitric acid to make a diacid containing 12 carbons. This acid is used to prepare some types of nylon, and its esters are used in synthetic lubricating oils. 

Acid-treated clay catalyst Engelhard F-24 was found to be very effective for the alkylation of diphenylamine (DPA) with an olefin such as a-methyl styrene (AMS) to obtain a mixture of mono and dialkylated diphenylamines (Chitnis and Sharma, 1995). For example, alkylation of DPA with AMS produced a mixture of 4-(a,a-dimethyl benzyl) diphenylamine, i.e. monocumyl-diphenylamine (MCDPA) and 4,4 -bis(a,a-dimethylbenzyl) diphenylamine, i.e. dicumyldiphenylamine (DCDPA) (Eqn.(l 1)). The dialkylated diphenylamine, i.e. DCDPA, is indu.strially important as an antioxidant and heat stabilizer. DCDPA is reported to be an ideal antioxidant for many materials like polyethylene, polypropylene, polyether polyol, polyacetals, nylon 6, synthetic lubricants, hot melt adhesives, etc. 

Examples of internal lubricants are fatty acid derivatives, e.g., stearates (for PVC), waxes and polyethylene oligomers containing polar groups obtained by partial oxidation. Not all polymers require lubricants LDPE, nylon and PET are self-lubricating. 

Nylon is used in gears, cams, brushes and other parts. Nylon moving parts do not need lubrication. 

Uses Antiseptic and disinfectant pharmaceuticals dyes indicators slimicide phenolic resins epoxy resins (bisphenol-A) nylon-6 (caprolactum) 2,4-D solvent for refining lubricating oils preparation of adipic acid, salicylic acid, phenolphthalein, pentachlorophenol, acetophenetidin, picric acid, anisole, phenoxyacetic acid, phenyl benzoate, 2-phenolsulfonic acid, 4-phenolsulfonic acid, 2-nitrophenol, 4-nitrophenol, 2,4,6-tribromophenol, 4-bromophenol, 4-/ert-butylphenol, salicylaldehyde, and many other organic compounds germicidal paints laboratory reagent. 

Uses. As a flame retardant on Nylon 6 fibers intermediate in the production of pesticides and herbicides as a stabilizer in oil and plaster an additive to lubricants... 

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