Lubrication polymer material additives

In addition to ILs as additives in liquid lubricant, they can also be added in polymer materials. Bermudez et al. [50, 51, 67, 68] performed several studies on the use of ILs as additives for polymer materials. They found that polymers to which ILs had been added produced better friction reduction and antiwear properties than blank polymer. 

In the polymer engineering we call compounds those intimate solid mixtures in which the technical polymer material for a specific application contains all the necessary additives -e.g. plasticizers, lubricants, impact modifiers, heat stabilizers, antioxidants, flame retardants, colorants, etc. — making the material suitable for the given task. A typical PVC compound e g. for a window profile, consists of 8 - 10 components [4],... 

Some studies with filled and unfilled rigid PVC were made in our laboratory to describe the effect of chalk as additional stabilizer. A suspension PVC (K-value 70) with an organotin stabilizer (2 phr) and lubricants (1.8 phr) was used as the experimental material. A part of this compound was filled with a stearic acid coated calcium carbonate (10 phr) as an additional component. The PVC powder and the additives were mixed at a high speed in an intensive mixer. The received dry blends were pelletized by extrusion to get a better dispersion of the additives in the polymer material. Finally, the granulates were processed by injection molding to test specimens for measurements of mechanical properties. 

Mutual interaction between lubricants and other additives in the plastic material (such as stabilizers, fillers, etc.) that may affect their affinity to the polymer and produce undesired effects, such as plate-out (deposition of residues from the melt on the metal surfaces of the processing equipment). 

Most polymers have to be processed into plastics for use in the production of commercially available articles. Plastic materials normally include polymer and a few per cent of one or more different additives such as anti-oxidants, photostabilizers, pigments, dyes, lubricants, fillers, etc. Prior to practical application, polymers are usually granulated and further mixed with other polymers (polymer blends), additives, etc. Such mixtures are further melted in an extruder in the processing step and converted to the final products. 

Plastics are compounds made up of resins (polymers) and additives. Additives, which are used to obtain specific effects in the plastic material during fabrication or use, expedite processing, heighten certain properties, provide color, and furnish the needed protection during fabrication and use. Some of the key additives used in thermoplastic piping are heat stabilizers, antioxidants, ultraviolet saeens, lubricants, pigments, property modifiers, and fillers. Table 2.1 lists some of the main additives used in plastic piping materials and their purpose. 

In addition to the fluoroplastics and fluororubbers already described other fluoropolymers have been marketed. Polymers of hexafluoropropylene oxide are marketed by Du Pont (Krytox). These materials have a low molecular weight (2000-7000) and are either oils or greases. The oils are uses as lubricants, heat transfer fluids and non-flammable oils for diffusion pumps. The greases are also used as lubricants. They have good heat and oil resistance but it is said that explosions may result from contact with the surfaces aluminium or magnesium cuttings. 

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