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Multifunctional lubricants

Hydraulic Fluids and Lubricants. The use of borate esters in hydraulic 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 multifunctional lubricant additives having antiwear and antifriction properties (45). [Pg.216]

ILs have attracted considerable attention in the field of tribology because of their remarkable lubrication and antiwear capabilities compared to lubrication oils, fit recent years, ILs have been applied and yielded excellent performance compared to traditional lubricants, but they have a number of problems, such as corrosion, oxidation instability, and very poor miscibility with base oil. These factors limit their industrial applications as lubricants [2]. Fortunately, these problems are not very difficult to address, as ILs have structures that may easily be modified. Conferring ILs with special functions, such as antioxidation and anticorrosion properties and enhanced capability for specific substrates, may be easily performed by synthetic chemists. It is hoped that future work on ILs will produce multifunctional lubricants with oxidation and corrosion resistance that may be applied in the industrial scale [2, 100]. [Pg.229]

Molybdenum dialkyldithiocarbamates Molybdenum dialkyldithiocarbamates are multifunctional lubricant additives as anti-wear, anti-friction and antioxidants. Molybdenum dialkyldithiocarbamates are also multifunctional antioxidants due to the hydroperoxide decomposing ability of dialkyldithiocarbamates, see Section 4.4.2, and the radical scavenging capacity of molybdenum. The best established structure for molybdenum dialkyldithiocarbamates is a six-coordinate complex of a dinuclear molybdenum centre with each molybdenum bonded to terminal oxygen or sulphur atoms, two bridging oxygen or sulphur atoms and one dialkyldithiocar-bamate ligand. Fig. 4.6 [44] ... [Pg.125]

Waxes are often used as multifunctional lubricants. These are generally paraffin hydrocarbon wax (melting point 65-75°C) and polyethylene wax (melting point 100-130°C). Being nonpolar, they are very incompatible with PVC, so they are used as external lubricants. Paraffin lubricants are typically used in rigid PVC pipe and profile extrusion applications at additive levels of 0.5-1.5 phr. Partially oxidized polyethylene wax works well as an external lubricant for PVC by delaying fusion... [Pg.331]

Low-MW EVA copolymers are also produced. These have broader solubility parameters than low-MW PE, and are usually multifunctional lubricants. They are... [Pg.334]

Simple primary amides such as stearamide, oleamide, and erucamide are widely used in polyolehns and styrenics as lubricants, but mainly in vinyl as release agents, discussed in the following. Aliphatic amides are strong enough nucleophiles (at process temperatures) to detract from the heat stability of PVC, and are therefore used at low levels or in situations where heat aging is not critical. When the latter is the case, the above amides are excellent multifunctional lubricants in flexible film and sheet. Stearamide is used mainly in filled applications, oleamide in clear or translucent sheet. Although it is feasible to formulate stabilizer systems that overcome effects on heat stability, there has been a trend towards replacement with ester lubricants. [Pg.336]

When mixed esters of polyols are prepared using, in part, a dibasic acid, the product is an ester lubricant that is a low polymer. This leads to a high order of resistance to extraction, bloom, or deposition. Pentaerythritol adipate-stearate is used in clear rigid PVC compounds as an efficient multifunctional lubricant, despite its relatively high cost. The corresponding adipate-oleate, a liquid, is more generally used in plasticized compounds in conjunction with mixed metal stabilizers, particularly if the latter are relatively nonlubricating. [Pg.337]

Paraffin wax is usually added late in the batch to avoid coating the resin grains. The relative level versus that of calcium stearate governs the rate of fusion of a specific PVC resin. Resin selection also plays a part. If paraffin wax and calcium stearate are added simultaneously, or if a multifunctional lubricant is included, then internal versus external behavior are difficult to distinguish. Both situations have their uses, to be discussed in connection with specific applications. [Pg.338]

Plasticized PVC compounds using mixed metal powder stabilizers are frequently based on calcium or barium stearate or laurate. In the presence of plasticizer, such stabilizers typically act as multifunctional lubricants. Liquid stabilizers often use analogous salts of liquid acids, such as those of octoic, oleic, or taU oil acids. These are similarly multifunctional, as are combinations with organotin stabilizers. In many cases, mixed metal stabifizers provide sufficient lubrication such that no further lubricants are needed. This must be considered in replacement of nonlubricating lead stabilizer systems. [Pg.338]

As the time interval between mixing and shaping is increased, opportunity for multifunctional behavior also increases. The examples dealing with calendering and molding of unplasticized compounds (Section 12.4) cover a number of multifunctional lubricant combinations. [Pg.341]

Flexible PVC is also fabricated from dry blend rather than fluxed compound. Internal and multifunctional lubricants are normally added with the plasticizer. Purely external lubricants such as paraffin and EBS wax are used, but most often ate added with the plasticizer and stabilizer, leading to complexing and multifunctional behavior. In some plasticized PVC compounds, external lubrication is obtained by use of multifunctional lubricants. The wide variety of applications for flexible PVC has led to a high degree of customizing of lubricant systems, often in conjunction with stabilizers developed for specific uses. [Pg.342]

Lead-stabilized products, used in some parts of the world in rigid extrusions, often contain 0.4-0.8 phr of calcium stearate as internal lubricant, 0.2-0.5 phr of stearyl alcohol to improve the mobility of the stabilizer (normally dibasic lead phosphate or combinations with tribasic lead sulfate), and 0.4-0.75 phr of partly saponified mon-tanic ester as a multifunctional lubricant. For the ultimate in process stability, calcium stearate may be replaced by a barium/cadmium stearate blend. The inclusion of cadmium also reduces the severity of staining by airborne sulfur compounds. Although lead-stabilized rigid compounds offer advantages in material cost and process safety, their use should be abandoned because of the hazard involved and because such usage is prejudicial to acceptance of vinyl products. [Pg.346]

Clear film and sheet tend to use 0-0.5 phr calcium stearate, with greater reliance on multifunctional lubricants. [Pg.346]

Flexible PVC film and sheet are now typically stabilized with barium/zinc and calcium/zinc liquids at levels of 2-3 phr. With plasticizer levels of 20-60 phr, the components of the liquid stabilizer also serve as multifunctional lubricants. This is often supplemented with 0.1-0.3 phr of stearic acid, particularly when high-efficiency liquids, used at 0.8-1.5 phr, replace standard liquid stabilizers. In some instances, the liquid stabilizer is supplemented with a powder booster, usually a... [Pg.347]

Comments Multifunctional Lubricant/stabilizers-Siding and profile... [Pg.61]

Comments Multifunctional Lubricant/stabilizers-Injection molding... [Pg.61]


See other pages where Multifunctional lubricants is mentioned: [Pg.984]    [Pg.329]    [Pg.336]    [Pg.338]    [Pg.339]    [Pg.341]    [Pg.341]    [Pg.341]    [Pg.345]    [Pg.346]    [Pg.347]    [Pg.348]    [Pg.348]    [Pg.349]    [Pg.61]   
See also in sourсe #XX -- [ Pg.32 , Pg.56 , Pg.57 , Pg.58 , Pg.59 , Pg.60 ]




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