And friction behavior

The fabric may also be given one or more of a number of other finishing treatments, either ia tandem with web formation and bonding or off-line as a separate operation, as a means of enhancing fabric performance or aesthetic properties. Performance properties iaclude functional characteristics such as moisture transport, absorbency, or repeUency flame retardancy electrical conductivity or static propensity abrasion resistance and frictional behavior. Aesthetic properties iaclude appearance, surface texture, and smell. 

Dutrowski [5] in 1969, and Johnson and coworkers [6] in 1971, independently, observed that relatively small particles, when in contact with each other or with a flat surface, deform, and these deformations are larger than those predicted by the Hertz theory. Johnson and coworkers [6] recognized that the excess deformation was due to the interfacial attractive forces, and modified the original Hertz theory to account for these interfacial forces. This led to the development of a new theory of contact mechanics, widely referred to as the JKR theory. Over the past two decades or so, the contact mechanics principles and the JKR theory have been employed extensively to study the adhesion and friction behavior of a variety of materials. 

Even though the load carrying capacity and friction behavior are apparently of interest to the authors, they are not presented here because no general law can be constructed if there are no practically reliable parameters presented. This remains to be done in our further research. 

The concentration of a small molecule reactant inside the polymer coils can be lower than outside when one uses a poor solvent for the polymer. This results in lower local and overall reaction rates. In the extreme, a poor solvent results in reaction occurring only on the surfaces of a polymer. Surface reactions are advantageous for applications requiring modification of surface properties without affecting the bulk physical properties of a polymer, such as modification of surface dyeability, biocompatibility, adhesive and frictional behavior, and coatability [Ward and McCarthy, 1989]. 

Film Thickness and Frictional Behavior of Some Liquid Crystals in Concentrated Point Contacts... 

Dissipation phenomena generally occur during measurement of the adherence of polymer materials, leading to an adherence energy function of both the number and nature of interfacial interactions (adhesion) and dissipative properties, mainly due to viscoelastic behavior [1-5]. Friction properties of polymers are also governed by interfacial interactions and dissipation mechanisms. Common phenomena (interfacial interaction and dissipation) therefore control adherence and friction behaviors. However, the relationship between the two phenomena is still vague or undefined. The first objective of this experimental work is then to compare adherence and friction of polydimethylsiloxane (PDMS) networks in order to establish relationships between these two properties. 

Bhimaraj P, Burris DL, Action J, Sawyer WG, Toney CG, Siegel RW, Schadler LS (2005) Effect of matrix morphology on the wear and friction behavior of alumina nanoparticle/poly (ethylene) lerephthalate composites. Wear 258(9) 1437-1443... 

Hard BN films obtained by an ion beam extracted from a borazine plasma were investigated in order to examine their adhesion and friction behavior. It was shown that sputter-cleaned film surfaces exhibit strong interfacial adhesion and high friction. The presence of adsorbates on the BN surfaces reduces their shear strength [116 to 118]. 

These presumptions are based on the results of chanical composition analyses and structural determinations by beam-based analytical methods. To verify the mechanisms involved, it is essential to clarify the frictional and mechanical properties of each layer in the multilayered structure of the tribofilm. Most importantly, with respect to the uppermost surface and the underlying area, which are thought to control the macroscale friction behavior, it is indispensable to determine differences not only in surface roughness, but also in shear strength and frictional behavior relative to depth on a nanometer scale. It is also important to make clear the distribution of the chemical composition relative to the tribofilm depth and to make this chemical distribution consistent with the nanometer-scale frictional and mechanical properties. However, estimating these properties experimentally on a nanometer scale is a difficult task, although several attempts have been made [24-28],... 

Shear Yield Stress and Friction Behavior near the Surface... 

In previous work by the participating authors (Nirmal and Yousif, 2009 Yousif et al., 2008), untreated betelnut fiber reinforced polyester (UT-BFRP) composite was used to study the wear and frictional behavior of the composite under diy contact condition. The work revealed that the average wear and friction coefficient of the composite were reduced by 98 and 73% compared to neat polyester namely when the fibers were oriented parallel to the sUding directioa... 

Compounded polymers prepared with thermoplastic elastomers (TPE) are prepared in much the same manner as thermoplastics, with some exceptions. Thermoplastic elastomers generally combine the flexibility and frictional behavior of mbber compounds with the practical forming considerations of thermoplastic materials. These are commonly encountered in automotive and appliance applications where non-slip surfaces are desirable. Since compounds in this class have elastomeric physical characteristics, this often requires that a twin-screw mixer makes use of... 

Sui G, Zhong WH, Ren X (2009) Stracture, mechanical properties and friction behavior of UHMWPE/HDPE/carbon nanofibers. Mater Chem Phys 115(1) 404—412... 

Liu, Y., Erdemir, A., Meletis, E.I., 1996. An investigation of the relationship between graphi-tization and frictional behavior of DLC coatings. Surface and Coatings Technology 86, 564-568. 

These results raise several important questions concerning static packings of frictional spheres (1) What determines the characteristic p that separates frictionless and frictional behavior of the structural and mechanical properties of static sphere packings (2) Since isotropic compression yields a well-defined... 

In a somewhat simplified characterization, different types of soft-touch coatings can be represented in terms of resin shear modulus and frictional behavior of the film surface (see Fig. 14). For better quantification of the latter, artificial fingertips for test purposes are currently under evaluation. 

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