Tribology of Polymers and Composites

Obviously, the potential application list is much more extensive. Polymers are used in tribological applications for many of the same reasons as they are used in structural applications. In many instances, polymers will perform a dual function as both a structural and a tribological material. An example of dual functionality is self-lubricated polymers that are injection molded into structural housings for low-speed lightly loaded rotating shafts. Concerns such as weight, cost, and manufacturability are some of the same issues with the use of polymers and polymeric composites for sliding applications as in structural applications. 

The following is a compilation of general comments about the use of polymers in industrial tribological applications. Polymer failure in tribological applications is often catastrophic, occurring in a very short timescale of the order of minutes or hours. 

The macroscopic or apparent area of contact is calculated from the formulas shown in Table 13.1. However, for very hard materials, such as metals and some 

W = Weight (force) per unit length for cylindrical contact, 

---

XPS has been used in almost every area in which the properties of surfaces are important. The most prominent areas can be deduced from conferences on surface analysis, especially from ECASIA, which is held every two years. These areas are adhesion, biomaterials, catalysis, ceramics and glasses, corrosion, environmental problems, magnetic materials, metals, micro- and optoelectronics, nanomaterials, polymers and composite materials, superconductors, thin films and coatings, and tribology and wear. The contributions to these conferences are also representative of actual surface-analytical problems and studies [2.33 a,b]. A few examples from the areas mentioned above are given below more comprehensive discussions of the applications of XPS are given elsewhere [1.1,1.3-1.9, 2.34—2.39]. 

Vladimir Kestelman, D.Sc., is an internationally respected expert on the mechanics and technology of composite materials and is president of KVN International, a worldwide consulting firm. An Academician of the Ukrainian Technological Academy, he is a former professor at Moscow Aviation Institute and the author of Electrophysical Phenomena in the Tribology of Polymers, Electrets in Engineering Fundamentals and Applications, and other books. He has published 26 books and 520 journal articles and holds 75 patents. 

Vizintin, J., M. Kalin, K. Dohda, and S. Jahanmir., eds. 2004. Tribology of Mechanical Systems A Guide to Present and Future Technologies. New York ASME Press. Addresses lubrication and appropriate Inbricants for all types of mechanical systems. Included are typical metal-based systems, such as engines, but also covered are materials, such as ceramics, polymers and composites. 

Inorganic particles are well known to enhance the mechanical and tribological properties of polymers, and this issue has been widely investigated in the past decades. It has been found that the particle size plays an important role in the improvement of the wear resistance. Reducing the particle size to a nano-scale level is assumed to Improve significantly the composite efficiency nanoparticle-filled polymers, the so-called polymer nanocomposites, are very promising... 

The data of Zink et al. (1998) illustrate the measurement by NRA of near-surface composition profiles in isotopically labelled polymer blends. If a mixture of polymers is adjacent to a phase interface (e.g. a solid or an air surface), often one of the components is preferentially attracted to the surface and will segregate to it, and this phenomenon will influence the tribological behaviour the interface (lubrication, wear and adhesion). 

Bermudez et al. [67] studied the tribological properties of PC+0.5%ZnO+1.5% IL composites and showed an 80% friction reduction and wear reduction of nearly two orders of magnitude with respect to PC+0.5% ZnO. They then investigated ILs as an effective lubricant additive of epoxy resin under the pin-on-disk configuration and showed a friction reduction higher than 50% and a wear rate reduction of two orders of magnitude for epoxy resin (RE)+1.5% IL with respect to the neat Re and Re+0.5% ZnO [68], The ability of ILs to act as lubricant additives of polymers under sliding conditions can thus be confirmed by the above report. 

VNY HIGH STRENGTH POLYMERS have been developed in recent years. The dreams of all-composite airplanes as well as artificial hearts have become realities. Thus, it is almost a necessity for chemists to acquire tribological information about these new polymers or composites and, vice versa, for tribologists to seek chemical knowledge about these materials. 

We are pleased to present, in this volume, 26 reviewed and revised chapters from the symposium in six parts mechanisms of polymer wear controls of polymer wear tribological behaviors of polymers wear of biomaterials and polymer composites characterization and measurements of polymer wear and degradation and wear of polymeric films and filaments. 

---