Ultra high molecular weight polyethylene, Industrial applications

Many polymer items are designed specifically to make contact with other materials. Where surface contact is concerned, two key properties are coefficient of friction and abrasion resistance. Polymers used in such applications include ultra high molecular weight polyethylene, polyacctal, fluorinated polymers, and natural and synthetic rubbers. Examples that we routinely come across include furniture upholstery, bushings and gears in office equipment, and bicycle tires. Industrial uses include the outer cover of electrical cables, and pipes that convey abrasive liquids such as slurries and powders. 

The focus in this chapter will be on the two main polyolefin polymers, namely polyethylene (PE) and polypropylene (PP). The latter especially has established itself as a very versatile fiber with unique applications in the textile and nonwoven industry. Polyethylene, on the other hand, has not been widely used as a fiber compared to other synthetic polymers such as PET, PP, and nylon, due in part to its low melting point. This chapter will, however, discuss ultra-high molecular weight polyethylene (UHMWPE) fiber that given its success and uniqueness in the synthetic fiber industry. 

Ultra high molecular weight polyethylene (UHMWPE) ways are usually made from extmded bars or strips. They have lower friction than metal ways and good corrosion resistance to many industrial fluids. They should have a surface finish of 32 to 125 microinches Ra. UHMWPE ways are good for use in dry or wet applications with straight-mnning or side-flexing flat-top chains. They do not absorb water and are not affected by moisture. 

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